CA1330402C - Lens shutter camera including zoom lens - Google Patents
Lens shutter camera including zoom lensInfo
- Publication number
- CA1330402C CA1330402C CA000616420A CA616420A CA1330402C CA 1330402 C CA1330402 C CA 1330402C CA 000616420 A CA000616420 A CA 000616420A CA 616420 A CA616420 A CA 616420A CA 1330402 C CA1330402 C CA 1330402C
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- Prior art keywords
- camera
- lens
- accordance
- light
- macro
- Prior art date
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Abstract
IN THE ABSTRACT A lens shutter type of camera is disclosed in which a zoom lens is positioned in a lens block (1) which has a sector gear (15) rotatably associated with the lens block and with a rotatable cam ring (14). The cam ring and sector gear are rotatable in a substantially constant axial position. A movable finder optical assembly (8) and a movable strobe assembly (9) are movable in association with movement of the zoom lens. The zoom lens is movable between an extreme telephoto position and an extreme wide angle position, as well a into a fully collapsed lens position beyond the extreme wide angle position and a macro or close-up photographing position beyond the extreme telephoto position. When the camera is in its macro mode, a prism (P1) is inserted into the finder optical assembly to correct for parallax; the strobe assembly is moved to change its illumination angle; and an optical wedge (4e) is pivoted into the path between a light receiver (4) and a light emitter (3e). A single cam plate (53) is provided to move the finder assembly and the strobe assembly. The photographic aperture (22b) can be selectively closed by barrier plates (31a) when the zoom lens is moved into its fully collapsed position. A light intercepting assembly (210) is provided for preventing light from entering the photographic optical assembly via cam grooves (20 and 21). This intercepting assembly includes a flexible code plate (90) which surrounds a peripheral portion of the cam ring (14) and which provides positional information relating to the position of the zoom lens.
Description
~330~02 LENS SHUTTER CAMERA INCLUDING ZOOM LENS
BACKGROUND OF THE DISCLOSURE
The present invention is a divisional application of copending Canadian Application No. 536,919, filed May 12, 1987.
1. Technical Field The present invention generally relates to a lens shutter , type of auto-focus camera, and more particularly to a zoom lens ¦ type of camera in which a zoom lens system is used as a taking j or photographing optical system, and in which a finder optical ~ 10 system and an electronic flash device (i.e., a strobe) are ', associated with the zooming operation of the zoom lens system.
In other words, the finder optical system and the strobe move in ~ coordinated fashion with zooming movement of the lens.
3 This application is related to the commonly assigned Canadian Application Serial No. 536,921, filed May 12, 1987, entitled "Zoom Lens Drive System for Lens Shutter Type of Camera".
BACKGROUND OF THE DISCLOSURE
The present invention is a divisional application of copending Canadian Application No. 536,919, filed May 12, 1987.
1. Technical Field The present invention generally relates to a lens shutter , type of auto-focus camera, and more particularly to a zoom lens ¦ type of camera in which a zoom lens system is used as a taking j or photographing optical system, and in which a finder optical ~ 10 system and an electronic flash device (i.e., a strobe) are ', associated with the zooming operation of the zoom lens system.
In other words, the finder optical system and the strobe move in ~ coordinated fashion with zooming movement of the lens.
3 This application is related to the commonly assigned Canadian Application Serial No. 536,921, filed May 12, 1987, entitled "Zoom Lens Drive System for Lens Shutter Type of Camera".
2. Backqround Art Generally, in conventional lens shutter (i.e., between the lens shutter) types of auto-focus cameras, it is impossible to vary the focal length of the photographic optical system. Other lens shutter types of auto-focus cameras comprise a two focal length system in which a lens is provided for varying the focal length and can be seiectively inserted in the photographing optical system. In such a system, two focal lengths are provided; however, it is possible to use only the two focal lengths provided, e.g., a wide angle and a telephoto range for the zoom lens, or, e.g., a standard range and a telephoto range for the zoom lens. While taking advantage of such dual focal lengths it is impossible to cover the range of focal lengths between the two extreme focal lengths, or between a wide angle and a medium telephoto focal length. Under such circumstances, ~; taking pictures with the use of a zoom lens has heretofore only been possible by using a single lens reflex camera.
However, single lens reflex cameras are more expensive and heavier than lens shutter type cameras, and, accordingly, it is ~ .
133~2 ~ 2 not easy for a photographer who is unfamiliar with cameras to freely use such single lens reflex cameras to freely use such single lens reflex cameras. Because of the heavy weight and relatively large size of such single lens reflex cameras, female photographers and travellers who are desirous of reducing the weight and the amount of baggage carried tend to hesitate to use such a single lens reflex (hereinafter SLR) camera, even if they appreciate the high quality pictures which are generally taken by such cameras.
Accordingly, users who would otherwise hesitate to use single lens reflex cameras which are relatively bulky and heavy, as noted above, have only two alternate choices: (a) a relatively small, light lens shutter type of automatic camera which has heretofore not been capable of controlling the focal length of the photographing optical system; or (b) a dual focal length type of auto-focus camera in which only two extreme focal lengths can be used.
An aspect of the present invention is the provision of a 20 small, light, compact lens shutter type of camera, with a zoom lens, drivable continuously between a wide angle position and a telephoto position, with means for driving the lens beyond the telephoto position, for a macro or close-up function.
In a further aspect, the camera has a distance measuring device automaticaliy focusing the optical system.
The present invention provides, in a preferred embodiment, a lens shutter-type of camera having a zoom lens driven by a motor, means for driving the zoom lens continuously between an extreme wide angle position and an extreme telephoto position, and means for driviny the zoom lens beyond the extreme telephone position into a close-up photographic position.
In a further embodiment, the camera is provided with a subject distance measuring device comprising means for determining the distance of a subject from a film plane in the camera, the camera having a photographic optical system which is automatically focused in accordance with the detected distance of the subject, the optical system being movable to the extreme ~ .
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However, single lens reflex cameras are more expensive and heavier than lens shutter type cameras, and, accordingly, it is ~ .
133~2 ~ 2 not easy for a photographer who is unfamiliar with cameras to freely use such single lens reflex cameras to freely use such single lens reflex cameras. Because of the heavy weight and relatively large size of such single lens reflex cameras, female photographers and travellers who are desirous of reducing the weight and the amount of baggage carried tend to hesitate to use such a single lens reflex (hereinafter SLR) camera, even if they appreciate the high quality pictures which are generally taken by such cameras.
Accordingly, users who would otherwise hesitate to use single lens reflex cameras which are relatively bulky and heavy, as noted above, have only two alternate choices: (a) a relatively small, light lens shutter type of automatic camera which has heretofore not been capable of controlling the focal length of the photographing optical system; or (b) a dual focal length type of auto-focus camera in which only two extreme focal lengths can be used.
An aspect of the present invention is the provision of a 20 small, light, compact lens shutter type of camera, with a zoom lens, drivable continuously between a wide angle position and a telephoto position, with means for driving the lens beyond the telephoto position, for a macro or close-up function.
In a further aspect, the camera has a distance measuring device automaticaliy focusing the optical system.
The present invention provides, in a preferred embodiment, a lens shutter-type of camera having a zoom lens driven by a motor, means for driving the zoom lens continuously between an extreme wide angle position and an extreme telephoto position, and means for driviny the zoom lens beyond the extreme telephone position into a close-up photographic position.
In a further embodiment, the camera is provided with a subject distance measuring device comprising means for determining the distance of a subject from a film plane in the camera, the camera having a photographic optical system which is automatically focused in accordance with the detected distance of the subject, the optical system being movable to the extreme ~ .
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- 3 -telephoto position and to the macro position, the subject distance measuring device comprising an optical element and means for selectively inserting the optical element into the optical path of the subject distance measuring device.
In yet another embodiment, a photographing zoom lens positionable within the camera, has at least a first lens group ~ and a second lens group, and means for positioning the zoom lens t` in the extreme wide angle position and in the extreme telephoto position, the zoom lens further comprising means for moving only , the first lens group into a position beyond the extreme telephoto position in order to provide close focusing of the lens when the camera is placed into the macro photographic mode.
~, In yet a further embodiment, in a camera having a zoom lens positionable in an extreme wide angle position, an extreme telephoto position, a plurality of variable magnification positions therebetween, and a macro photographing position located beyond the telephoto position, an auto-focus assembly comprising a light emitter and a light receiver, the light receiver comprising a position sensing device, wherein the position sensing device comprises a first area which is used to sense the position of a subject during automatic focusing of the camera for all lens positions except the macro position, and a second area closely adjacent to the first area which comprises means for sensing tne position of a subject during macro focusing of the camera.
In another embodiment, a camera comprises a zoom lens which is movable between an extreme wide angle position, an extreme telephoto position, a plurality of variable magnification positions between the two extreme positions, and a macro focusing position beyond the telephoto position; a device for measuring the distance of a subject from the film plane of the camera, a measuring device including a light receiver and a light emitter;
an optical element which is selectively positionable in the optical path between the light receiver and the emitter; means for driving the lens, and means for positioning the optical element between the light receiver and the light emitter when the lens is driven into the macro position. ~-:
~33~2
In yet another embodiment, a photographing zoom lens positionable within the camera, has at least a first lens group ~ and a second lens group, and means for positioning the zoom lens t` in the extreme wide angle position and in the extreme telephoto position, the zoom lens further comprising means for moving only , the first lens group into a position beyond the extreme telephoto position in order to provide close focusing of the lens when the camera is placed into the macro photographic mode.
~, In yet a further embodiment, in a camera having a zoom lens positionable in an extreme wide angle position, an extreme telephoto position, a plurality of variable magnification positions therebetween, and a macro photographing position located beyond the telephoto position, an auto-focus assembly comprising a light emitter and a light receiver, the light receiver comprising a position sensing device, wherein the position sensing device comprises a first area which is used to sense the position of a subject during automatic focusing of the camera for all lens positions except the macro position, and a second area closely adjacent to the first area which comprises means for sensing tne position of a subject during macro focusing of the camera.
In another embodiment, a camera comprises a zoom lens which is movable between an extreme wide angle position, an extreme telephoto position, a plurality of variable magnification positions between the two extreme positions, and a macro focusing position beyond the telephoto position; a device for measuring the distance of a subject from the film plane of the camera, a measuring device including a light receiver and a light emitter;
an optical element which is selectively positionable in the optical path between the light receiver and the emitter; means for driving the lens, and means for positioning the optical element between the light receiver and the light emitter when the lens is driven into the macro position. ~-:
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- 4 Other aspects, features and advantages of the present inventi~n will hereinafter be described.
BRIEF DESCRIPTION OF DRAWINGS
The above and other aspects, features and advantages of the present invention will be described in greater detail with respect to the accompanying drawings, in which like reference numerals represent similar elements throughout the several views, and wherein:
Fig. 1 is a schematic perspective view of a first embodiment of a lens shutter type of camera having a zoom lens formed in accordance with the present invention;
Fig. 2 is a front elevational view of a lens barrel block, a light emitter, a light receiver, and a macro-compensating optical element which forms a part of a distance measuring device, together with a zooming motor, all forming a portion of the invention of Fig. 1;
Fig. 3 is a top plan view of the apparatus of Fig. 2;
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i ~ P5713S01 5 , Fig. 4 is a sectional view ta~en along line IV-IV of Fig. 2;
Fig. 5 is a sectional view of the apparatus of Fig. 2 taken along line V-V of Fig. 2; ~ -5Fig. 6 is a longitudinal sectional view of a lens barrel block and two photographing optical lenses formed in accordance with the present invention;
~ Fig. 7 is a developed view of the camming i grooves in a "flattened" cam ring used to surround the ~ 10 front and rear lens element groups of the photographic 1' optical system of the camera of Fig. l;
Fig. 8 is an exploded perspective view of a lens barrel block used in the camera of Fig. l;
Fig. 9 is a sectional view illustrating an optical arrangement for adjusting the focus point of the camera when the camera is placed into its macro mode;
Fig. 10 is an enlarged plan view of the prism, frame (i.e., mask) and one light receptor lens of the system of ~ Fig. 9;
20Fig. 11 is a front elevational view illustrating the assembly of Fig. 10;
Fig. 12 is a sectional view of an optical arrangement -~
used in a two lens group zooming lens in the camera of Fig. ~-~
25Fig. 13 is a schematic view illustrating the light emitter and light receptor of a distance measuring device used in the camera of Fig. l;
Fig. 14 is a~ sectional view of an optical arran!gement of a system for adjusting the focal point of the object '~ 30 distance measuring system when the camera is in a macro `-~ mode;
Figs. 15A - 17A are vertical sectional views of a first embodiment of a finder optical system used in accordance ~ with the present invention, in which:
`~ 35Fig. 15A is a side plan view of the finder optical assembly when in a wide field, small magnification position: ~
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~33~02 , P5713SOl - 6 Fig. 16A is a plan view of the assembly of Fig. 15A
when the camera is in a narrow field, large magnification ~; mode;
Fig. 17A is a plan view of the assembly of Fig. 15A
when the camera is in a narrow field, large magnification ;~ position when the camera is in its macro mode;
-;3 Figs. 15B, 16B and 17B, respectively, illustrate the aberrations of the optical systems of Figs. 15A, 16A and ~; 17A, respectively;
d 10 Figs. 18A-2OB are all vertical sectional views of a second embodiment of a finder optical system formed in accordance with the present invention in which:
Fig. 18A is a plan view of the optical system when the ~3~ camera is in a wide field, small magnification mode;
Fig. l9A is a plan view of the optical system when the camera is in a narrow field, large magnification mode; and Fig. 20A is a plan view of the optical system when the ~: camera is in a narrow field, large magnification macro mode;
Figs. 18B, l9B and 20~, respectively, are all views illustrating the aberrations for the finder optical assembly when it is in the positions of Figs. 18A, l9A and 20A, respectively;
Fig. 21 is a plan view of a cam plate which can be attached to a portion of the finder block and the strobe 2S lamp assembly of the present invention;
Fig. 22 is a sectional view taken along line XXII-XXII
of Fig. 21;
Fig. 23 is a b~ack plan view of the aam plate of Fig.
Fig. 24 is a plan view of the apparatus of Fig. 21 with the cam plate removed;
Fig~ 25 is a sectional view taken along line XXV-XXV of Fig. 21;
Fig. 26 is a sectional view taken along lin~. XXVI-XXVI
35 of Fig. 25 showing the finder plate in a first position; ;
Fiq. ~7 is a sectionel view similar to that of Fig. 25 t33~2 P5713SOl _ 7 but illustrating the finder plate in a second, operational position;
Fig. 28 is a sectional view similar to the view of Fig.
26, in which a deflecting prism actuating plate has been removed to facilitate consideration;
Fig. 29 is a front elevational view of the apparatus of Fig. 25, shown in a position in which a deflection prism actuating plate is inserted;
Fig. 30 is a sectional view taken along line XXX-XXX of ~ -Fig. 29;
Figs. 31 and 32 are sectional views of a first embodiment of an optical barrier mechanism, as viewed along a plane which is perpendicular to an optical axis, when in ¦~ its open position with the central lens frame opening being open;
Fig. 32 is a sectional view similar to that of Fig. 31 ~; but illustrating the optical barrier mechanism when it is in its closed position; -Fig. 33 is a sectional view of a second embodiment of ~ 20 an optical barrier mechanism formed in accordance with the - present invention, the view being similar to that of the first embodiment of the optical barrier mechanism i~
illustrated in Fig. 31;
Fig. 34 is a sectional view of the optical barrier -25 mechanism of Fig. 33 in its closed position, similar to the ~-view of the embodiment of Fig. 32; ~
Fig. 35 is an exploded perspective view of a light --intercepting mechanism positioned adjacent to a lens barrel ~ block;
i~ 30 Fig. 36 is a perspective view of a light intercepting ring;
Fig. 37 is a sectional view taken along line XXXVII-XXXVII of Fig. 36;
Fig. 38 is a sectional view of a second embodiment of a light intercepting ring formed in accordance with the ~ present invention which is similar to the view of Fig. 37;
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,, :3 P5713S01 Fig. 39 is an exploded perspective view of one embodiment of a guiding device for a flexible printed circuit board (i.e., an FPC) with the cam ring being ~ partially cut away;
,3 5 Fig. 40 is a perspective view of the FPC board guide ~ member of Fig. 39;
¦ Fig. 41 is a sectional view of a mechanical arrangement J of an FPC board guide plate with respect to the space defined between the cam ring and a front lens ~roup frame;
Fig. 42 is a side elevational view of an FPC board which is illustrated in extension (in dashed lines) and in a `~ deformed position (in solid lines), respectively;
-~ Fig. 43 is a side elevational view of a light intercepting means used in association with an FPC board;
Fig. 44 is a developed or schematic view of a code plate, with the lens of the code plate and grooves of the cam being illustrated on a flattened cam ring, illustrating the functional relationship between conductive lands on the code plate and the cam (ring and plate) grooves;
Fig. 45 is a table illustrating the zoom code on the code plate of Fig. 44 and the stopping positions which are located on the code plate;
Fig. 46 is a front elevational view of the operational switches of a camera formed in accordance with the present invention;
Fig. 47 is a back elevational view of the camera of the present invention illustrating a zooming lens operation switch thereon;
Fig. 48 is a top plan view of the camera of Figs. 46 ~ 30 and 47, illustrating additional operational switches;
i~ Fig. 49 is a schematic sectional view illustrating a ~ mode changing switch formed in accordance with the present `~ invention in a first, inoperative position;
Fig. 50 is a sectional view of a mode changing switch and a macro button illustrated in a second operational position;
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P~713S01 _ g Fig. 51 is a schematic view of an alternative telephoto-wide angle switch of the camera of the present invention;
Fig. 52 is a front plan view of a finder optical system lens having a plurality of bright frames thereon;
Fig. 53A is a perspective view of a double-wedge shaped prism used in the present finder optical system;
Fig. 5~B is a top plan view of the prism of Fig. 53A;
and Fig. 53C is a right hand side plan view of the prism of Fig. 53A.
BEST MODE FOR CARRYING OUT THE INVENTION
The present invention will now be described below in greater detail, with specific reference to the accompanying drawings which illustrate a variety of embodiments and features of the present invention.
The description will be generally provided in ~
: accordance with the following general sub headings: ~ -A. The Overall Camera Construction for a Lens Shutter Type of Camera B. Distance Measuring Device, i.e., Range Finder, and Camera Macro Functioning Thereof C. Finder Optical System D. Finder and Strobe Driving Mechanisms E. Barrier, i.e., Lens Cap, Mechanism F. Light Interception Assembly and Mechanism G. FPC Board Guide and Anti-Reflection Mechanism H. ~echanism for Detecting Information Relating to the Position of the Zoom Lens A. Overall Camera Construction for a Lens Shutter TvPe of Camera ;
The overall construction of a lens shutter type of camera formed in accordance with the present invention is well illustrated in Figs. 1-8. A lens shutter type of camera formed in accordance with the present invention essentially comprises a zoom lens barrel block 1, a finder :
1 3 3 ~
P5713Sol and strobe block 2 (hereinafter referred to as a finder block), a light emitter 3 and a light receiver 4 forming a portion of a distance measuring, i.e., AF, device, and a zooming motor 5 which is used for the zooming opération of the photographing optical system. All of these elements are secured to a base 6 which forms an immovable portion of the camera body.
Base 6 includes, as is best illustrated in Figs. 2-4, a lens barrel supporting plate portion 6a which lies in a plane which is perpendicular to the optical axis of the lens; and a horizontal supporting plate portion 6b is provided which extends at right angles from the lens barrel support plate portion 6a. Support plate portion 6b extends beyond the side edge of plate 6a, as seen in Fig. 2, in order to support finder assembly 8 and strobe assembly 9.
The base further comprises motor supporting plate portions 6c which are positioned perpendicularly with respect to the ---horizontal support plate portion 6b. Lens barrel block 1 is supported on lens barrel support plate portion 6a, which has a central opening (unreferenced) for receiving the lens barrel block as illustrated in Fig. 2. A zooming motor 5 is attached to motor support plate portions 6c and is located above the central portion of lens barrel block 1.
Preferably, only a single such motor te.g., a DC motor) is used to drivingly engage all of the movable elements of the system. A distance measuring device includes a light emitter 3 and a light receiver 4, which are secured to the -~
horizontal support~plate portion 6b of base 6, and which are located on opposite sides of zooming motor 5 (see Figs. 2 and 3). Finder block 2 is secured to the right hand portion of horizontal support plate portion 6b, as viewed from the front of the camera as seen in Fig. 2. A gear train support plate portion 6e is connected to motor support plate portion 6~ via spacer 6f, as best illustrated in Fig. 3. ~-Lens barrel block 1 is adapted to be actuated by zooming motor 5, and the construction of this bloc~ will be ;
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described hereinbelow with more specific reference to Figs.
6-lo. A rear securing plate 11 is mounted to lens barrel support plate portion 6a of base 6 by fastening screws lo, as is best illustrated in Fig. 6. Rear securing plate 11 includes four guide rods 12 which are attached to and through bores in the rear portion of the guide plate and which are located about the optical axis of the photographing optical system and parallel to this axis. A
front securing plate 13 is secured to the front ends of guide rods 12; these guide rods and plates are the main securing elements for lens barrel block 1.
A rotatable cam ring 14 is positioned between front and rear securing plates 13 and 11, respectively; a sector gear 15 is provided about a substantial portion (but preferably not the entire 360) of the outer periphery of cam ring 14;
this gear can be attached to the cam ring by conventional means, e.g., via set screws 15a, as seen in Fig. 6: this gear is adapted to engage, either directly or indirectly, a first pinion 7 (Fig. 1) which is positioned between the gear train support plate 6e and the motor support plate portion 6c, as seen in Figs. 3 and (particularly) Fig. 5. Gear 15 can be a sector gear which will cover a predetermined range of rotational movement of cam ring 14; a turning recess 44a and cam surface 44 are provided adjacent to each other on (a flat surface portion of) the gear. The cam ring is itself provided with zooming cam grooves 20 and 21 (see Fig.
7) which are used to engage the front and rear lens element ~: groups, re`spectively.
Fig. 7 is a schematic or developed view of zooming cam grooves 20 and 21 of ring 14. Cam groove 21, used to engage the rear lens element group, includes an extreme wide angle ~` fixing section 21a, a variable magnification section 21b -~ in~lined upwardly (as seen in Fig. 7) from section 21a, and ~- an extreme telephoto fixing section 21c. Cam groove 20, used for the front lens element group, includes a section ~ 20a for opening and closing barrier block 30, a lens .',:
1 330'~02 P5713Sol retraction section 20b, an extreme wide angle fixing section 20c, a variable ~agnification section 20d, an extreme telephoto fixing section 20e, a macro transfer section 20f, and an extreme macro fixing section 20g.
When the term macro is used throughout this specification, it refers to a ~Iclose-up~ photographing configuration for the camera. Previously, the term "macro"
has occasionally been used to mean "bigger than life"; -however, the term macro has been used throughout this specification as an equivalent term for close-up, and whenever it is used it should be taken to have such a meaning unless indicated to the contrary herein.
The total angle 0 1 of the rotational displacement of cam ring opening and closing section 20a, lens retraction section 20b, and extreme wide angle fixing section 20c of zooming cam groove 20 is identical to angle 0 1 of the extreme wide angle fixing section 21a of zooming cam groove 21. Angle 0 2 of the variable magnification, i.e., variable power, section 20d of zooming cam groove 20 is identical to angle~32 of the variable magnification, i.e., variable power, section 21b of zooming cam groove 21. Further, the total angle ~ 3 of the extreme telephoto fixing section 20e, the macro position fixing section 20g, and the macro transfer section 20f, is equal to the angle 0 3 of the extreme telephoto fixing section 21c. In the illustrated embodiment, the zooming range is between approximately 35mm and approximately 70mm.
A roller 17, as illustrated in both Figs. 6 and 8, is positioned within zooming cam groove 20; this roller is ` 30 attached to a front lens group frame 16. A roller 19 of rear lens group frame 18 is positioned within zooming cam groove 21, again as illustrated in Figs. 6 and 8. Front lens group frame 16 and rear lens group frame 18 are movably guided by guide rods 12, and a decorative frame 22 and shutter block 23 are secured to the front lens group frame 16 via set screws 22a, as best seen in the exploded view of ;:
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Fig. 8, as well as in the cross-sectional view o~ Fig. -~
6.
The front lens frame 24 which supports front lens element group L1 is engaged by shutter block 23 via helicoid 25, which is shown in Fig. 8. Front lens frame 24 includes an arm 24a which engages lens feeding lever 23a of shutter block 23 (see Fig. 6), 50 that when lens feeding lever 23a rotates in a circumferential direction in order to rotate front lens frame 24, the front lens frame will move along -the direction of the optical axis of the photographing optical system under the guidance of helicoid 25.
Rear lens element group L2 is directly attached to rear lens group frame 18, as seen in Fig. 6. One desired configuration of lens groups L1 and L2, as illustrated in Fig. 6, are disclosed in commonly assigned U.S. Patent No. 4,720,179.
The structure of shutter block 23 is known per se. This shutter block rotates lens feeding lever 23a over a predetermined angular displacement in accordance with a detection signal which is received by the shutter block from the distance measuring device, as described hereinafter, via a pulse motor which is incorporated within the camera body and which is a~apted to open shutter sector 23b, which has been closed for a predetermined time, and to thereafter ~-return lens feeding lever 23a into its original position after the shutter has again closed. This type of shutter block is disclosed, e.g., in unexamined Japanese Published Patent Application (KOKAI) No. 60-235,126 dated November 21, 1985. The present camera utilizes such a shutter block in the ~ fundamental way disclosed therein.
i~ Finder block 2 includes finder assembly 8 and strobe assembly 9. The finder device and the strobe -~
device are adapted to vary, respectively, the field of ~inder view and the illumination angle, i.e., the intensity of the strobe, ~3~02 P5713SOl in accordance with variance in the focal length of the lens barrel block l. Zooming motor 5 is used as a power source both for finder control and strobe control; only a single motor need therefore be used.
As seen in Fig. 1, sector gear 15 of cam ring 14 is engaged by a second pinion 50 which is different from the first pinion 7 referred to previously. Shaft 51, to which pinion 50 is attached, extends rearwardly towards the rear portion of base 6, and is provided with a reduction gear train 52 adjacent a rear end of the shaft. The reduction gear train includes a final gear 52a which meshes with a rack 53a of movable cam plate 53. This substantially flat cam plate 53 is slidable in right and left hand lateral directions, as viewed in Fig. l, and includes a downwardly bent portion 53b at its rear end, as best shown in ~ig. 1.
Rack 53a is ~ormed on the lower end of bent portion 53b of cam plate 53. Reduction gear train 52 is adapted to reduce rotation of gear 15 in order to restrict or limit the lateral movement of cam plate 53. The cam plate is provided with a variable power cam groove 55 for guiding movement of finder device 8, a parallax correction cam groove 56, and a strobe cam groove 57 for guiding movement of strobe device 9.
The lens system used in finder optical assembly 8 essentially comprises a subject lens group L3, an eyepiece group L4, and a movable variable power lens group L5, and further comprises a deflection prism Pl which is used when the camera is placedlinto the macro or close-up mode.
Variable power lens group L5 makes the image picture size, which is adapted to vary in accordance with the variable power operation of lens barrel block l, be coincident with the field of view in finder device 8.
Deflection prism Pl will enter the optical path of the finder lens system only in the macro mode, in order to adjust parallax which otherwise occurs in such mode.
~pecifically, parallax which inevitably occurs when using , . j f:
~33~2 lens shutter type of cameras will increase as the subject whose picture is being taken approaches the camera; and, accordingly, a large parallax would normally result in the macro mode. In order to solve this problem and reduce the large parallax which otherwise occurs in the macro mode, deflection prism Pl is provided in the form of a wedge with a thicker lower end and a thinner upper end. Deflection prism Pl, when located along the optical axis of the finder optical system, serves to deflect rays downwardly in order to take a picture of a subject which is located extremely close to the camera. Fig. 28 illustrates the optical path of light rays when the deflection prism Pl is located along the optical axis of the camera. As described hereinafter, the wedge prism which is used is preferably selected to be a double wedge prism, which varies in width in both the vertical and in the horizontal directions, as clearly illustrated in Figures 53A, B and C. The use of such a prism bends the light rays downwardly and rightwardly, to move them into substantial alignment with the photographic optical axis.
Strobe assembly 9 restricts or limits the illumination angle when the focal length of the photographing lens is large, namely, as the zoom lens is fed forwardly; and the strobe assembly 9 is moved to increase the illumination angle in the macro mode, in order to decrease the amount of light which reaches the subject. In the embodiment illustrated, strobe device 9 includes a fixed Fresnel Lens L6, a movable cOncalve reflector 59, and a xenon lamp 58 which can be moved along the direction of the optical axis of the strobe. Alternately, a simple strobe could be used in which the illumination angle would be fixed. Although such a strobe arrangement is possible, it is preferable to move the lamp in the optical axis direction in accordance with movement of the zoom lens in order to optimize the quantity of light given to a subject during photography, dependent upon the position occupied by the photographing ~
' ~3~0 ~2 optical system in the zoom lens.
~. Distance l~easurinq Device, i.e.. Ran~e Finder. and camera Macro Function Before looking in a detailed fashion at thé distance measuring device of the present invention and its relationship to the macro function of the camera, the relationship be~ween the distance of a subject from the two lens group zoom lens and the displacement or forward feed of the zoom lens will be now be discussed.
~ig. 12 illustrates a relatively simple construction for a two lens group zoom lens. In such a construction, the distance of the subject and the aisplacement of the zoom lens have a relationship as follows:
U=fl (2+X/fl+fl/X) + HH + ~ ...(1), wherein:
U equals the distance of a subject from the film plane;
fl equals the focal length of the first lens group;
X equals the displacement of the zoom lens;
HH equals the principal point distance; and ~ equals the distance between the focal point of the first lens group and the focal point of the two ~lPns group zoom lens.
From equation ~1) it can be calculated that:
X={-2fl-HH-delta+U- ¦ (2fl+HH+delta-U)2-4fl ~/2 ...(2) Fig. 13 illustrates the relationship between the distance U of a subject and the positional deviation (t) on a position detection element 4a, which forms a portion of the distance measurilng device which detects the distance of a subject from the film plane based upon the principle of ,~ 30 triangulation.
The triangulation distance measuring device includes a light emitter 3 having a light source 3a and a light emitting lens 3b; and a light receiver 4 having a light receiving lens 4b and a position detection element 4a, e.g., a photo sensitive detector (hereinafter PSD). The rays of light emitted from light source 3a are reflected by the i, .
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P~713S01 subject, and the light reflected therefrom is received by position detecting sensor 4a in order to detect the distance of the subject from the film plane F. Namely, the deviation (t) of the image on position detection sensor ~a, from a reference point represented by the position of an image of a subject at an infinite distance, relative to distance U of the subject from film plane ~, is given by the following equation:
t=Lxf/(U-f-d) ...(3), in which:
L represents the base length of the distance measuring device;
f represents the focal length of the light receiving lens;
and d represents the distance between film plane F and the focal plane of the light receiving lens.
The deviation (t) can be detected by the electric current, i.e., output, of position detecting sensor 4a in ~ -accordance with the guantity of light received by position detecting sensor 4a, in a well known fashion. The photographing optical system of the camera is adjusted to form an image on a focal point of the image plane in accordance with the output signal, i.e., electric current, of position detecting sensor 4a, based upon equations (2) and (3), so that automatic focusing can be effected. The actuating or driving mechanism of the photographic optical ; system is noted above.
It is necessary to shift the range of measurement of the subject distance by the distance measuring device towards a close subject distance side in order to achieve the macro function of the camera. In the macro mode, the photographing optical system is either partially or entirely displaced, from a standard picture taking position, towards the subject to be taken, as is well known.
In the embodiment of Fig. 12, the first lens group of the photographing lens is moved forward, towards the subject over a predetermined displacement, in the macro mode, ~ 3 3 ~ 2 P5713SOl independently of (and beyond) the displacement effected by the automatic focusing device during normal photography.
Fig. 14 represents one meohanism for shifting the range of measurement of the subject distance in the macro mode in accordance with the present invention. In Fig. 14, a relatively conventional prism P having an apex angle of S is inserted in front of light receiving lens 4b in order to shift the range o~ measurement of the subject distance towards the subject whose photograph is being taken. In other words, the zoom lens camera system uses a pivotable prism or wedge which is adapted to be positioned in front of light receiver 4.
Assuming, e.g., that the apex angle and the refractive index of prism P are ~ and n, respectively, the deviation t 15 of the image on position detecting sensor 4a, with respect ~
to the subject distance Ul, can be obtained as follows: ;
firstly, the incident angle alpha of the rays of light on the plane of prism P adjacent to the subject is determined by the following equation:
alpha=tan~l {L/(Ul-f-d)} +
Refraction angle beta of the rays of light which are incident upon prism P having an apex angle ~ at the incident angle alpha is determined by the following equation:
beta=alpha- S +sin l [n sin { ~ - sin (alpha/n))], and, therefore ~ ~o~ - S ~
Accordingly, deviation tl of the image on position detecting sensor 4a willlbe determined by tl=f x tan ~ .
Subject distance Umfl, which is obtained when light which is coincident with the optical axis of light receiving lens 4b intersects the optical axis of light emitting lens 3b is determined as follows, provided that the thickness of prism P is negligible:
; Umfl=L/tan ~sin l (n sin ~ +f~d.
In one example, the present Applicants calculated the values of U, Ul, t, tl, and t-tl, in a camera in which the "
~ . "
~33~a2 photographing optical system included a two lens group zoom lens, wherein: fl, i.e., the focal length of the first group, equals 24.68mm; HH (i.e. ,the principal point distance) eguals 7.02mm; delta, i.e., the distance between
BRIEF DESCRIPTION OF DRAWINGS
The above and other aspects, features and advantages of the present invention will be described in greater detail with respect to the accompanying drawings, in which like reference numerals represent similar elements throughout the several views, and wherein:
Fig. 1 is a schematic perspective view of a first embodiment of a lens shutter type of camera having a zoom lens formed in accordance with the present invention;
Fig. 2 is a front elevational view of a lens barrel block, a light emitter, a light receiver, and a macro-compensating optical element which forms a part of a distance measuring device, together with a zooming motor, all forming a portion of the invention of Fig. 1;
Fig. 3 is a top plan view of the apparatus of Fig. 2;
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i ~ P5713S01 5 , Fig. 4 is a sectional view ta~en along line IV-IV of Fig. 2;
Fig. 5 is a sectional view of the apparatus of Fig. 2 taken along line V-V of Fig. 2; ~ -5Fig. 6 is a longitudinal sectional view of a lens barrel block and two photographing optical lenses formed in accordance with the present invention;
~ Fig. 7 is a developed view of the camming i grooves in a "flattened" cam ring used to surround the ~ 10 front and rear lens element groups of the photographic 1' optical system of the camera of Fig. l;
Fig. 8 is an exploded perspective view of a lens barrel block used in the camera of Fig. l;
Fig. 9 is a sectional view illustrating an optical arrangement for adjusting the focus point of the camera when the camera is placed into its macro mode;
Fig. 10 is an enlarged plan view of the prism, frame (i.e., mask) and one light receptor lens of the system of ~ Fig. 9;
20Fig. 11 is a front elevational view illustrating the assembly of Fig. 10;
Fig. 12 is a sectional view of an optical arrangement -~
used in a two lens group zooming lens in the camera of Fig. ~-~
25Fig. 13 is a schematic view illustrating the light emitter and light receptor of a distance measuring device used in the camera of Fig. l;
Fig. 14 is a~ sectional view of an optical arran!gement of a system for adjusting the focal point of the object '~ 30 distance measuring system when the camera is in a macro `-~ mode;
Figs. 15A - 17A are vertical sectional views of a first embodiment of a finder optical system used in accordance ~ with the present invention, in which:
`~ 35Fig. 15A is a side plan view of the finder optical assembly when in a wide field, small magnification position: ~
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.
~33~02 , P5713SOl - 6 Fig. 16A is a plan view of the assembly of Fig. 15A
when the camera is in a narrow field, large magnification ~; mode;
Fig. 17A is a plan view of the assembly of Fig. 15A
when the camera is in a narrow field, large magnification ;~ position when the camera is in its macro mode;
-;3 Figs. 15B, 16B and 17B, respectively, illustrate the aberrations of the optical systems of Figs. 15A, 16A and ~; 17A, respectively;
d 10 Figs. 18A-2OB are all vertical sectional views of a second embodiment of a finder optical system formed in accordance with the present invention in which:
Fig. 18A is a plan view of the optical system when the ~3~ camera is in a wide field, small magnification mode;
Fig. l9A is a plan view of the optical system when the camera is in a narrow field, large magnification mode; and Fig. 20A is a plan view of the optical system when the ~: camera is in a narrow field, large magnification macro mode;
Figs. 18B, l9B and 20~, respectively, are all views illustrating the aberrations for the finder optical assembly when it is in the positions of Figs. 18A, l9A and 20A, respectively;
Fig. 21 is a plan view of a cam plate which can be attached to a portion of the finder block and the strobe 2S lamp assembly of the present invention;
Fig. 22 is a sectional view taken along line XXII-XXII
of Fig. 21;
Fig. 23 is a b~ack plan view of the aam plate of Fig.
Fig. 24 is a plan view of the apparatus of Fig. 21 with the cam plate removed;
Fig~ 25 is a sectional view taken along line XXV-XXV of Fig. 21;
Fig. 26 is a sectional view taken along lin~. XXVI-XXVI
35 of Fig. 25 showing the finder plate in a first position; ;
Fiq. ~7 is a sectionel view similar to that of Fig. 25 t33~2 P5713SOl _ 7 but illustrating the finder plate in a second, operational position;
Fig. 28 is a sectional view similar to the view of Fig.
26, in which a deflecting prism actuating plate has been removed to facilitate consideration;
Fig. 29 is a front elevational view of the apparatus of Fig. 25, shown in a position in which a deflection prism actuating plate is inserted;
Fig. 30 is a sectional view taken along line XXX-XXX of ~ -Fig. 29;
Figs. 31 and 32 are sectional views of a first embodiment of an optical barrier mechanism, as viewed along a plane which is perpendicular to an optical axis, when in ¦~ its open position with the central lens frame opening being open;
Fig. 32 is a sectional view similar to that of Fig. 31 ~; but illustrating the optical barrier mechanism when it is in its closed position; -Fig. 33 is a sectional view of a second embodiment of ~ 20 an optical barrier mechanism formed in accordance with the - present invention, the view being similar to that of the first embodiment of the optical barrier mechanism i~
illustrated in Fig. 31;
Fig. 34 is a sectional view of the optical barrier -25 mechanism of Fig. 33 in its closed position, similar to the ~-view of the embodiment of Fig. 32; ~
Fig. 35 is an exploded perspective view of a light --intercepting mechanism positioned adjacent to a lens barrel ~ block;
i~ 30 Fig. 36 is a perspective view of a light intercepting ring;
Fig. 37 is a sectional view taken along line XXXVII-XXXVII of Fig. 36;
Fig. 38 is a sectional view of a second embodiment of a light intercepting ring formed in accordance with the ~ present invention which is similar to the view of Fig. 37;
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,, :3 P5713S01 Fig. 39 is an exploded perspective view of one embodiment of a guiding device for a flexible printed circuit board (i.e., an FPC) with the cam ring being ~ partially cut away;
,3 5 Fig. 40 is a perspective view of the FPC board guide ~ member of Fig. 39;
¦ Fig. 41 is a sectional view of a mechanical arrangement J of an FPC board guide plate with respect to the space defined between the cam ring and a front lens ~roup frame;
Fig. 42 is a side elevational view of an FPC board which is illustrated in extension (in dashed lines) and in a `~ deformed position (in solid lines), respectively;
-~ Fig. 43 is a side elevational view of a light intercepting means used in association with an FPC board;
Fig. 44 is a developed or schematic view of a code plate, with the lens of the code plate and grooves of the cam being illustrated on a flattened cam ring, illustrating the functional relationship between conductive lands on the code plate and the cam (ring and plate) grooves;
Fig. 45 is a table illustrating the zoom code on the code plate of Fig. 44 and the stopping positions which are located on the code plate;
Fig. 46 is a front elevational view of the operational switches of a camera formed in accordance with the present invention;
Fig. 47 is a back elevational view of the camera of the present invention illustrating a zooming lens operation switch thereon;
Fig. 48 is a top plan view of the camera of Figs. 46 ~ 30 and 47, illustrating additional operational switches;
i~ Fig. 49 is a schematic sectional view illustrating a ~ mode changing switch formed in accordance with the present `~ invention in a first, inoperative position;
Fig. 50 is a sectional view of a mode changing switch and a macro button illustrated in a second operational position;
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l330~a~ :
P~713S01 _ g Fig. 51 is a schematic view of an alternative telephoto-wide angle switch of the camera of the present invention;
Fig. 52 is a front plan view of a finder optical system lens having a plurality of bright frames thereon;
Fig. 53A is a perspective view of a double-wedge shaped prism used in the present finder optical system;
Fig. 5~B is a top plan view of the prism of Fig. 53A;
and Fig. 53C is a right hand side plan view of the prism of Fig. 53A.
BEST MODE FOR CARRYING OUT THE INVENTION
The present invention will now be described below in greater detail, with specific reference to the accompanying drawings which illustrate a variety of embodiments and features of the present invention.
The description will be generally provided in ~
: accordance with the following general sub headings: ~ -A. The Overall Camera Construction for a Lens Shutter Type of Camera B. Distance Measuring Device, i.e., Range Finder, and Camera Macro Functioning Thereof C. Finder Optical System D. Finder and Strobe Driving Mechanisms E. Barrier, i.e., Lens Cap, Mechanism F. Light Interception Assembly and Mechanism G. FPC Board Guide and Anti-Reflection Mechanism H. ~echanism for Detecting Information Relating to the Position of the Zoom Lens A. Overall Camera Construction for a Lens Shutter TvPe of Camera ;
The overall construction of a lens shutter type of camera formed in accordance with the present invention is well illustrated in Figs. 1-8. A lens shutter type of camera formed in accordance with the present invention essentially comprises a zoom lens barrel block 1, a finder :
1 3 3 ~
P5713Sol and strobe block 2 (hereinafter referred to as a finder block), a light emitter 3 and a light receiver 4 forming a portion of a distance measuring, i.e., AF, device, and a zooming motor 5 which is used for the zooming opération of the photographing optical system. All of these elements are secured to a base 6 which forms an immovable portion of the camera body.
Base 6 includes, as is best illustrated in Figs. 2-4, a lens barrel supporting plate portion 6a which lies in a plane which is perpendicular to the optical axis of the lens; and a horizontal supporting plate portion 6b is provided which extends at right angles from the lens barrel support plate portion 6a. Support plate portion 6b extends beyond the side edge of plate 6a, as seen in Fig. 2, in order to support finder assembly 8 and strobe assembly 9.
The base further comprises motor supporting plate portions 6c which are positioned perpendicularly with respect to the ---horizontal support plate portion 6b. Lens barrel block 1 is supported on lens barrel support plate portion 6a, which has a central opening (unreferenced) for receiving the lens barrel block as illustrated in Fig. 2. A zooming motor 5 is attached to motor support plate portions 6c and is located above the central portion of lens barrel block 1.
Preferably, only a single such motor te.g., a DC motor) is used to drivingly engage all of the movable elements of the system. A distance measuring device includes a light emitter 3 and a light receiver 4, which are secured to the -~
horizontal support~plate portion 6b of base 6, and which are located on opposite sides of zooming motor 5 (see Figs. 2 and 3). Finder block 2 is secured to the right hand portion of horizontal support plate portion 6b, as viewed from the front of the camera as seen in Fig. 2. A gear train support plate portion 6e is connected to motor support plate portion 6~ via spacer 6f, as best illustrated in Fig. 3. ~-Lens barrel block 1 is adapted to be actuated by zooming motor 5, and the construction of this bloc~ will be ;
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described hereinbelow with more specific reference to Figs.
6-lo. A rear securing plate 11 is mounted to lens barrel support plate portion 6a of base 6 by fastening screws lo, as is best illustrated in Fig. 6. Rear securing plate 11 includes four guide rods 12 which are attached to and through bores in the rear portion of the guide plate and which are located about the optical axis of the photographing optical system and parallel to this axis. A
front securing plate 13 is secured to the front ends of guide rods 12; these guide rods and plates are the main securing elements for lens barrel block 1.
A rotatable cam ring 14 is positioned between front and rear securing plates 13 and 11, respectively; a sector gear 15 is provided about a substantial portion (but preferably not the entire 360) of the outer periphery of cam ring 14;
this gear can be attached to the cam ring by conventional means, e.g., via set screws 15a, as seen in Fig. 6: this gear is adapted to engage, either directly or indirectly, a first pinion 7 (Fig. 1) which is positioned between the gear train support plate 6e and the motor support plate portion 6c, as seen in Figs. 3 and (particularly) Fig. 5. Gear 15 can be a sector gear which will cover a predetermined range of rotational movement of cam ring 14; a turning recess 44a and cam surface 44 are provided adjacent to each other on (a flat surface portion of) the gear. The cam ring is itself provided with zooming cam grooves 20 and 21 (see Fig.
7) which are used to engage the front and rear lens element ~: groups, re`spectively.
Fig. 7 is a schematic or developed view of zooming cam grooves 20 and 21 of ring 14. Cam groove 21, used to engage the rear lens element group, includes an extreme wide angle ~` fixing section 21a, a variable magnification section 21b -~ in~lined upwardly (as seen in Fig. 7) from section 21a, and ~- an extreme telephoto fixing section 21c. Cam groove 20, used for the front lens element group, includes a section ~ 20a for opening and closing barrier block 30, a lens .',:
1 330'~02 P5713Sol retraction section 20b, an extreme wide angle fixing section 20c, a variable ~agnification section 20d, an extreme telephoto fixing section 20e, a macro transfer section 20f, and an extreme macro fixing section 20g.
When the term macro is used throughout this specification, it refers to a ~Iclose-up~ photographing configuration for the camera. Previously, the term "macro"
has occasionally been used to mean "bigger than life"; -however, the term macro has been used throughout this specification as an equivalent term for close-up, and whenever it is used it should be taken to have such a meaning unless indicated to the contrary herein.
The total angle 0 1 of the rotational displacement of cam ring opening and closing section 20a, lens retraction section 20b, and extreme wide angle fixing section 20c of zooming cam groove 20 is identical to angle 0 1 of the extreme wide angle fixing section 21a of zooming cam groove 21. Angle 0 2 of the variable magnification, i.e., variable power, section 20d of zooming cam groove 20 is identical to angle~32 of the variable magnification, i.e., variable power, section 21b of zooming cam groove 21. Further, the total angle ~ 3 of the extreme telephoto fixing section 20e, the macro position fixing section 20g, and the macro transfer section 20f, is equal to the angle 0 3 of the extreme telephoto fixing section 21c. In the illustrated embodiment, the zooming range is between approximately 35mm and approximately 70mm.
A roller 17, as illustrated in both Figs. 6 and 8, is positioned within zooming cam groove 20; this roller is ` 30 attached to a front lens group frame 16. A roller 19 of rear lens group frame 18 is positioned within zooming cam groove 21, again as illustrated in Figs. 6 and 8. Front lens group frame 16 and rear lens group frame 18 are movably guided by guide rods 12, and a decorative frame 22 and shutter block 23 are secured to the front lens group frame 16 via set screws 22a, as best seen in the exploded view of ;:
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Fig. 8, as well as in the cross-sectional view o~ Fig. -~
6.
The front lens frame 24 which supports front lens element group L1 is engaged by shutter block 23 via helicoid 25, which is shown in Fig. 8. Front lens frame 24 includes an arm 24a which engages lens feeding lever 23a of shutter block 23 (see Fig. 6), 50 that when lens feeding lever 23a rotates in a circumferential direction in order to rotate front lens frame 24, the front lens frame will move along -the direction of the optical axis of the photographing optical system under the guidance of helicoid 25.
Rear lens element group L2 is directly attached to rear lens group frame 18, as seen in Fig. 6. One desired configuration of lens groups L1 and L2, as illustrated in Fig. 6, are disclosed in commonly assigned U.S. Patent No. 4,720,179.
The structure of shutter block 23 is known per se. This shutter block rotates lens feeding lever 23a over a predetermined angular displacement in accordance with a detection signal which is received by the shutter block from the distance measuring device, as described hereinafter, via a pulse motor which is incorporated within the camera body and which is a~apted to open shutter sector 23b, which has been closed for a predetermined time, and to thereafter ~-return lens feeding lever 23a into its original position after the shutter has again closed. This type of shutter block is disclosed, e.g., in unexamined Japanese Published Patent Application (KOKAI) No. 60-235,126 dated November 21, 1985. The present camera utilizes such a shutter block in the ~ fundamental way disclosed therein.
i~ Finder block 2 includes finder assembly 8 and strobe assembly 9. The finder device and the strobe -~
device are adapted to vary, respectively, the field of ~inder view and the illumination angle, i.e., the intensity of the strobe, ~3~02 P5713SOl in accordance with variance in the focal length of the lens barrel block l. Zooming motor 5 is used as a power source both for finder control and strobe control; only a single motor need therefore be used.
As seen in Fig. 1, sector gear 15 of cam ring 14 is engaged by a second pinion 50 which is different from the first pinion 7 referred to previously. Shaft 51, to which pinion 50 is attached, extends rearwardly towards the rear portion of base 6, and is provided with a reduction gear train 52 adjacent a rear end of the shaft. The reduction gear train includes a final gear 52a which meshes with a rack 53a of movable cam plate 53. This substantially flat cam plate 53 is slidable in right and left hand lateral directions, as viewed in Fig. l, and includes a downwardly bent portion 53b at its rear end, as best shown in ~ig. 1.
Rack 53a is ~ormed on the lower end of bent portion 53b of cam plate 53. Reduction gear train 52 is adapted to reduce rotation of gear 15 in order to restrict or limit the lateral movement of cam plate 53. The cam plate is provided with a variable power cam groove 55 for guiding movement of finder device 8, a parallax correction cam groove 56, and a strobe cam groove 57 for guiding movement of strobe device 9.
The lens system used in finder optical assembly 8 essentially comprises a subject lens group L3, an eyepiece group L4, and a movable variable power lens group L5, and further comprises a deflection prism Pl which is used when the camera is placedlinto the macro or close-up mode.
Variable power lens group L5 makes the image picture size, which is adapted to vary in accordance with the variable power operation of lens barrel block l, be coincident with the field of view in finder device 8.
Deflection prism Pl will enter the optical path of the finder lens system only in the macro mode, in order to adjust parallax which otherwise occurs in such mode.
~pecifically, parallax which inevitably occurs when using , . j f:
~33~2 lens shutter type of cameras will increase as the subject whose picture is being taken approaches the camera; and, accordingly, a large parallax would normally result in the macro mode. In order to solve this problem and reduce the large parallax which otherwise occurs in the macro mode, deflection prism Pl is provided in the form of a wedge with a thicker lower end and a thinner upper end. Deflection prism Pl, when located along the optical axis of the finder optical system, serves to deflect rays downwardly in order to take a picture of a subject which is located extremely close to the camera. Fig. 28 illustrates the optical path of light rays when the deflection prism Pl is located along the optical axis of the camera. As described hereinafter, the wedge prism which is used is preferably selected to be a double wedge prism, which varies in width in both the vertical and in the horizontal directions, as clearly illustrated in Figures 53A, B and C. The use of such a prism bends the light rays downwardly and rightwardly, to move them into substantial alignment with the photographic optical axis.
Strobe assembly 9 restricts or limits the illumination angle when the focal length of the photographing lens is large, namely, as the zoom lens is fed forwardly; and the strobe assembly 9 is moved to increase the illumination angle in the macro mode, in order to decrease the amount of light which reaches the subject. In the embodiment illustrated, strobe device 9 includes a fixed Fresnel Lens L6, a movable cOncalve reflector 59, and a xenon lamp 58 which can be moved along the direction of the optical axis of the strobe. Alternately, a simple strobe could be used in which the illumination angle would be fixed. Although such a strobe arrangement is possible, it is preferable to move the lamp in the optical axis direction in accordance with movement of the zoom lens in order to optimize the quantity of light given to a subject during photography, dependent upon the position occupied by the photographing ~
' ~3~0 ~2 optical system in the zoom lens.
~. Distance l~easurinq Device, i.e.. Ran~e Finder. and camera Macro Function Before looking in a detailed fashion at thé distance measuring device of the present invention and its relationship to the macro function of the camera, the relationship be~ween the distance of a subject from the two lens group zoom lens and the displacement or forward feed of the zoom lens will be now be discussed.
~ig. 12 illustrates a relatively simple construction for a two lens group zoom lens. In such a construction, the distance of the subject and the aisplacement of the zoom lens have a relationship as follows:
U=fl (2+X/fl+fl/X) + HH + ~ ...(1), wherein:
U equals the distance of a subject from the film plane;
fl equals the focal length of the first lens group;
X equals the displacement of the zoom lens;
HH equals the principal point distance; and ~ equals the distance between the focal point of the first lens group and the focal point of the two ~lPns group zoom lens.
From equation ~1) it can be calculated that:
X={-2fl-HH-delta+U- ¦ (2fl+HH+delta-U)2-4fl ~/2 ...(2) Fig. 13 illustrates the relationship between the distance U of a subject and the positional deviation (t) on a position detection element 4a, which forms a portion of the distance measurilng device which detects the distance of a subject from the film plane based upon the principle of ,~ 30 triangulation.
The triangulation distance measuring device includes a light emitter 3 having a light source 3a and a light emitting lens 3b; and a light receiver 4 having a light receiving lens 4b and a position detection element 4a, e.g., a photo sensitive detector (hereinafter PSD). The rays of light emitted from light source 3a are reflected by the i, .
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P~713S01 subject, and the light reflected therefrom is received by position detecting sensor 4a in order to detect the distance of the subject from the film plane F. Namely, the deviation (t) of the image on position detection sensor ~a, from a reference point represented by the position of an image of a subject at an infinite distance, relative to distance U of the subject from film plane ~, is given by the following equation:
t=Lxf/(U-f-d) ...(3), in which:
L represents the base length of the distance measuring device;
f represents the focal length of the light receiving lens;
and d represents the distance between film plane F and the focal plane of the light receiving lens.
The deviation (t) can be detected by the electric current, i.e., output, of position detecting sensor 4a in ~ -accordance with the guantity of light received by position detecting sensor 4a, in a well known fashion. The photographing optical system of the camera is adjusted to form an image on a focal point of the image plane in accordance with the output signal, i.e., electric current, of position detecting sensor 4a, based upon equations (2) and (3), so that automatic focusing can be effected. The actuating or driving mechanism of the photographic optical ; system is noted above.
It is necessary to shift the range of measurement of the subject distance by the distance measuring device towards a close subject distance side in order to achieve the macro function of the camera. In the macro mode, the photographing optical system is either partially or entirely displaced, from a standard picture taking position, towards the subject to be taken, as is well known.
In the embodiment of Fig. 12, the first lens group of the photographing lens is moved forward, towards the subject over a predetermined displacement, in the macro mode, ~ 3 3 ~ 2 P5713SOl independently of (and beyond) the displacement effected by the automatic focusing device during normal photography.
Fig. 14 represents one meohanism for shifting the range of measurement of the subject distance in the macro mode in accordance with the present invention. In Fig. 14, a relatively conventional prism P having an apex angle of S is inserted in front of light receiving lens 4b in order to shift the range o~ measurement of the subject distance towards the subject whose photograph is being taken. In other words, the zoom lens camera system uses a pivotable prism or wedge which is adapted to be positioned in front of light receiver 4.
Assuming, e.g., that the apex angle and the refractive index of prism P are ~ and n, respectively, the deviation t 15 of the image on position detecting sensor 4a, with respect ~
to the subject distance Ul, can be obtained as follows: ;
firstly, the incident angle alpha of the rays of light on the plane of prism P adjacent to the subject is determined by the following equation:
alpha=tan~l {L/(Ul-f-d)} +
Refraction angle beta of the rays of light which are incident upon prism P having an apex angle ~ at the incident angle alpha is determined by the following equation:
beta=alpha- S +sin l [n sin { ~ - sin (alpha/n))], and, therefore ~ ~o~ - S ~
Accordingly, deviation tl of the image on position detecting sensor 4a willlbe determined by tl=f x tan ~ .
Subject distance Umfl, which is obtained when light which is coincident with the optical axis of light receiving lens 4b intersects the optical axis of light emitting lens 3b is determined as follows, provided that the thickness of prism P is negligible:
; Umfl=L/tan ~sin l (n sin ~ +f~d.
In one example, the present Applicants calculated the values of U, Ul, t, tl, and t-tl, in a camera in which the "
~ . "
~33~a2 photographing optical system included a two lens group zoom lens, wherein: fl, i.e., the focal length of the first group, equals 24.68mm; HH (i.e. ,the principal point distance) eguals 7.02mm; delta, i.e., the distance between
5 the focal point of the first lens group and the focal point of the zoom lens, e~als 3~.04mm;
d, i.e., the distance between the film plane and the focal plane of the light receiving lens, equals 6.292mm; the displacement of the first group at the macro setting equals lO 0.5502mm.; L, i.e., the base length of the distance measuring device, equals 30mm; f, i.e., the focal length of the light recelving lens, equals 20mm.; S, i.e., the apex angle of the prism P, equals 2.826; n, i.e., the refractive index of prism P, equals 1.483; the distance range which can lS be measured equals 0.973m- infinity; and the number of steps of forward feeding movement of the zoom lens is 18, so that the range of 0.973m - 6m is divided into 17 forward feeding -motion steps of the zoom lens. The results of these calculations are illustrated in Table l hereinbelow. In 20 these calculations, the distance range of 0.973m- 6m is shifted towards the range of 0.580m- 1.020m.
In Table 1 hereinafter, step 17-18 represents a shifting point at which the 17th step changes to the 18th step; similarly, the step 0-l represents a point of transfer 25 between 0 and the first step.
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~5713S01 - 20 POSITIONS OF IMAGES ON THE POSITION D~TECTING SENSOR
AT DIFFERENT SUBJECT DISTANCES
STEP NO. U (m) U l(m) t(mm) _l(mm) tl-t (mm) 517-18 6.000 1.020 0.1004 0.12740.0270 17 5.154 0.996 0.1170 0.14230.0253 16 4.027 0.951 0.1500 0.17190.0219 3.310 0.911 0.1827 0.20130.0186 14 2.814 0.875 0.2153 0.23050.0153 1013 2.450 0.841 0.2476 0.25950.0120 12 2.172 0.810 0.2797 0.28840.0087 11 1.952 0.7~2 0.3115 0.3170o.oo55 o 1.775 0.756 0.3432 0.34550.0023 -9 1.628 0.732 0.3747 0.3738-0.0009 15 8 1.504 0.709 0.4059 0.4018-0.0041-7 1.399 0.6a8 0.4369 0.4298-0.0072
d, i.e., the distance between the film plane and the focal plane of the light receiving lens, equals 6.292mm; the displacement of the first group at the macro setting equals lO 0.5502mm.; L, i.e., the base length of the distance measuring device, equals 30mm; f, i.e., the focal length of the light recelving lens, equals 20mm.; S, i.e., the apex angle of the prism P, equals 2.826; n, i.e., the refractive index of prism P, equals 1.483; the distance range which can lS be measured equals 0.973m- infinity; and the number of steps of forward feeding movement of the zoom lens is 18, so that the range of 0.973m - 6m is divided into 17 forward feeding -motion steps of the zoom lens. The results of these calculations are illustrated in Table l hereinbelow. In 20 these calculations, the distance range of 0.973m- 6m is shifted towards the range of 0.580m- 1.020m.
In Table 1 hereinafter, step 17-18 represents a shifting point at which the 17th step changes to the 18th step; similarly, the step 0-l represents a point of transfer 25 between 0 and the first step.
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~5713S01 - 20 POSITIONS OF IMAGES ON THE POSITION D~TECTING SENSOR
AT DIFFERENT SUBJECT DISTANCES
STEP NO. U (m) U l(m) t(mm) _l(mm) tl-t (mm) 517-18 6.000 1.020 0.1004 0.12740.0270 17 5.154 0.996 0.1170 0.14230.0253 16 4.027 0.951 0.1500 0.17190.0219 3.310 0.911 0.1827 0.20130.0186 14 2.814 0.875 0.2153 0.23050.0153 1013 2.450 0.841 0.2476 0.25950.0120 12 2.172 0.810 0.2797 0.28840.0087 11 1.952 0.7~2 0.3115 0.3170o.oo55 o 1.775 0.756 0.3432 0.34550.0023 -9 1.628 0.732 0.3747 0.3738-0.0009 15 8 1.504 0.709 0.4059 0.4018-0.0041-7 1.399 0.6a8 0.4369 0.4298-0.0072
6 1.309 0.668 0.4678 0.4575-0.0103 1.230 0.650 0.4984 0.4850-0.0134 4 1.161 0.633 0.5288 0.5124-0.0165 20 3 ~.100 0.616 0.5591 0.5396-0.0195 2 1.045 0.601 0.5891 0.5666-0.0225 1 0.996 0.587 0.6189 0.5934-0.0255 0-1 0.973 0.580 0.6338 0.6068-0.0270 U mfl=1.283m -25As can be seen from Table 1, an image deviation of 0.027mm occurs at t~e position detecting sensor 4a at the two extremities of the range of measurement of the subject distance which can be measured, as a result of compensation ~
by prism P. Such a deviation corresponds substantially to ~;
about 1 step, in the sense of the number of feeding steps of the zoom lens. Accordingly, it is not possible to move the -;~photographic lens into a correct focal point by directly controlling displacement of the photographing optical system in response to the output of position detecting sensor 4a, thus resulting in an "out of focus" situation.
In other words, it is impossible to com21etely ~ ~33~02 ~-compensate for deviation in the images by using only prism P, since the rate o~ change of deviation tl of the image on position detecting sensor 4a with respect to su~ject distance Ul cannot be varied by prism P. The prism begins to compensate for the image deviation, but cannot alone do so .
In view of such results, the present inventors have found that complete compensation of such deviation can be achieved if the rate of deviation tl is adjusted by multiplying this rate by 1.1130 (calculated by dividin~
0.5334 by 0.4794), which equals the change in t from step o-1 to step 17-18 divided by the change in tl betwcen step 0-1 and step 17-18, since decreases in the deviations t and tl between steps 17-18 and 0-1 are 0.5334mm and 0.4794mm, respectively. To this end, in the present invention, a macro mode compensating optical element is adapted to be selectively moved in front of the distance measuring optical system only when the camera is placed in the macro mode, in -order to optically extend the base length between the light emitter and the light receiver of the distance measuring optical system, and in order to intersect the optical axis of the light emitter and the optical axis of the light receiver with a finite distance. Further, in this embodiment, an actuating mechanism is provided for moving 2~ the macro compensating optical element in front of the light receiver in coordination with transfer or movement of the photographing optical system, i.e., the zoom lens, from the ~ -normal photographic mode to the macro mode, as discussed in detail hereinafter.
Figure 9 illustrates an optical arrangement of the distance measuring device when in the macro mode, in the automatic focus camera of the present invention. In this ^~ figure, macro compensating element 4e comprises a prism 4c and a mas~ or frame 4d, rather than only the optical wedge `
of Fig. 14. Element 4e is moved in front of light receiving lens 4b of the distance measuring device when the camera is :~
:
1330l~2 ..;
P5713Sol - 22 in the macro setting. In the normal photographic mode~
element 4e is retracted away from the optlcal axis of light receiving lens 4b.
Prior to discussing the mechanical structure which is adapted to actuate the compensation element 4e, the actual construction of the macro compensating element 4e and the reasons why measurement accuracy can be improved or increased in the macro mode will be described in detail.
The element includes a prism 4c which is adapted to optically extend the base length of the distance measuring device and to refract rays of light which enter the prism.
Figure 10 iilustrates in detail prism 4c, mask 4d, and light receiving lens 4b. Figure 11 is a front elevational view of Figure 10; and both of these figures illustrate how mask or frame 4d is capable of intercepting rays of light out of the path of light approaching the prism. Mask 4d includes a front opening 4f which is shown in the form of a generally rectangular, elongated slot, on the (front) side of the frame located most closely adjacent to the subject being photographed, and a rear opening 4g (see Fig. 10) on the side of the frame or mask most closely adjacent to light receiving lens 4b. Opening 4f is in the form of a slit spaced from optical axis O of light receiving lens 4b by a distance (1) which is measured on the opposite side of the optical axis from light emitting lens 3b. Rear opening 4g is also in the form of a elongated slit, which is substantially located along the optical axis O of light ~receiv;ng lens 4b.~
When prism 4c, together with mask 4d, move in front of }ight receiving lens 4b, i.e., when the camera is in the macro mode, a first lens group of the photographic lens is fed forwardly by a constant displacement, independently of the displacement of the lens which is fed forwardly during the normal photographic mode by the automatic focusing device. As best seen in Figs. 9 and 10, when prism 4c is located in front of light receiving lens 4b, the range of 13~0 ~2 P5713S01 ~ - 23 measurement of the distance of the subject can be shifted to the macro mode range. Prism 4c serves to move light incident thereon in a parallel fashion, over a displacement (l) in the direction of the base length, so that base length L can be optically extended to equal the distance (L+l).
Assuming that the angle and the refractive index of prism 4c are ~ l~ and n, respectively, and that the parallel displacement of light by prism 4c is represented by the distance (1), deviation t2 of the image on position detecting element 4a, as viewed with respect to the subject distance U2, can be obtained as hereinafter detailed.
The incident angle of light on the plane of prism 4c which is adjacent to the ~ubject is provided by the following equation:
alphal=tan l {(L+l)/(U2-f-d)) + ~ l This equation indicates that the base length of the triangulation distance measuring device is extended from L
to (L+l) by the insertion of prism 4c in front of the light receiving lens 4b. The refraction angle betal of light which is incident upon a prism having an angle ~ 1~ which light is incident upon the prism at an incident angle of alphal, is calculated in accordance with the following equation:
betal = alphal- ~ l+sin _l~nsin { ~ l-sin (alphal/n))], and, therefore: ~ l = alphal ~ ~ l ~ betal-Accordingly, deviation t2 of the image on positiondetecting sensor 4a is equal to f x tan ~ l' i.e., t2 = F x ~, , , ~ i ~
tan O
The subject distance Umf2 which is obtained when light coincident with the optical axis of light receiving lens 4b intersects the optical axis of light emitting lens 3b is yielded by using the following equation, provided that the thickness of prism 4c is negligible:
Umf2=(L+l)/tan (sin l(n x sin ~ 1} +f+d.
Table 2 hereinafter illustrates the results of the calculations in which the distance measuring device of Figs.
l3304a2 P5713S01 ~ 24 10 and 11 has been applied to a photographing lens satisfying the same basic criteria as those mentioned with respect to the embodiment of Figure 14, i.e., namely that:
(a) The photographic lens is a 2-group lens;
(b)fl, i.e., the focal length of the first group, equals 24.68 mm;
(c) HH, i.e., the principal point distance, equals 7.02mm;
(d) delta, i.e., the distance between the focal length of the first lens group and the focal length of the zoom lens, equals 30.04 mm;
(e) d, i.e., the distance between the film plane and the focal plane of the light receiving lens, equals 6.292mm;
(f) the displacement of the first lens group in the macro setting equals 0.5502mm;
(g) L, i.e., the base length of the distance measuring device, equals 30mm;
(h) f, i.e., the focal length of the light receiving lens, equals 20mm;
i.e., the angle of prism 4c, equals 3.39;
(j) n, i.e., the refraction index of the ~
prism, equals 1.483; ~ ! -(k) (1), i.e., the distance representing the parallel displacement of the rays of :~ light, equals 3.39mm;
;~ (1) the range of measurement of the distance of the subject which can be ~
measured equals 0.973m- infinity; ~;
(m) the number of steps of forward feeding movement of the zoom lens is i8;
~3304~2 P5713Sol - 25 (n) the range of 0.973m- 6m is divided into 17 steps; and (o) the photographic range of 0.973m- 6m is shifted into the range of 0.580m-1.020m.
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POSXTIONS OF IMAGES ON THE POSITION DETECTING SENSOR AT
DIFFERENT SUBJECT DISTANCES WITH THE MACRO COMPENSATION
ELEMENT OF FIGURES 9, lo AND 11 STEP NO. U (m) U 2 (m) t(mm) _2(mm) -2 t (mm) 17-18 6.000 1.020 0.1004 0.1005 o.OOOl 17 5.154 0.996 0.1170 0.1171 O.Oool 16 4.027 0.951 0.1500 0.1500 o 1015 3.310 o.9ll 0.1827 0.1827 o 14 2.814 0.875 0.2153 0.2152 -o.oool 13 2.450 0.841 0.2476 0.2475 -O.oool 12 2;172 0.810 0.2797 o.2796 -0.0001 11 1.952 0.782 0.3115 0.3115 0 1510 1.775 0.756 0.3432 0.3432 o 9 1.628 0.732 0.3747 0.3746 -0.0001 8 1.504 0.709 0.4059 0.4059 o
by prism P. Such a deviation corresponds substantially to ~;
about 1 step, in the sense of the number of feeding steps of the zoom lens. Accordingly, it is not possible to move the -;~photographic lens into a correct focal point by directly controlling displacement of the photographing optical system in response to the output of position detecting sensor 4a, thus resulting in an "out of focus" situation.
In other words, it is impossible to com21etely ~ ~33~02 ~-compensate for deviation in the images by using only prism P, since the rate o~ change of deviation tl of the image on position detecting sensor 4a with respect to su~ject distance Ul cannot be varied by prism P. The prism begins to compensate for the image deviation, but cannot alone do so .
In view of such results, the present inventors have found that complete compensation of such deviation can be achieved if the rate of deviation tl is adjusted by multiplying this rate by 1.1130 (calculated by dividin~
0.5334 by 0.4794), which equals the change in t from step o-1 to step 17-18 divided by the change in tl betwcen step 0-1 and step 17-18, since decreases in the deviations t and tl between steps 17-18 and 0-1 are 0.5334mm and 0.4794mm, respectively. To this end, in the present invention, a macro mode compensating optical element is adapted to be selectively moved in front of the distance measuring optical system only when the camera is placed in the macro mode, in -order to optically extend the base length between the light emitter and the light receiver of the distance measuring optical system, and in order to intersect the optical axis of the light emitter and the optical axis of the light receiver with a finite distance. Further, in this embodiment, an actuating mechanism is provided for moving 2~ the macro compensating optical element in front of the light receiver in coordination with transfer or movement of the photographing optical system, i.e., the zoom lens, from the ~ -normal photographic mode to the macro mode, as discussed in detail hereinafter.
Figure 9 illustrates an optical arrangement of the distance measuring device when in the macro mode, in the automatic focus camera of the present invention. In this ^~ figure, macro compensating element 4e comprises a prism 4c and a mas~ or frame 4d, rather than only the optical wedge `
of Fig. 14. Element 4e is moved in front of light receiving lens 4b of the distance measuring device when the camera is :~
:
1330l~2 ..;
P5713Sol - 22 in the macro setting. In the normal photographic mode~
element 4e is retracted away from the optlcal axis of light receiving lens 4b.
Prior to discussing the mechanical structure which is adapted to actuate the compensation element 4e, the actual construction of the macro compensating element 4e and the reasons why measurement accuracy can be improved or increased in the macro mode will be described in detail.
The element includes a prism 4c which is adapted to optically extend the base length of the distance measuring device and to refract rays of light which enter the prism.
Figure 10 iilustrates in detail prism 4c, mask 4d, and light receiving lens 4b. Figure 11 is a front elevational view of Figure 10; and both of these figures illustrate how mask or frame 4d is capable of intercepting rays of light out of the path of light approaching the prism. Mask 4d includes a front opening 4f which is shown in the form of a generally rectangular, elongated slot, on the (front) side of the frame located most closely adjacent to the subject being photographed, and a rear opening 4g (see Fig. 10) on the side of the frame or mask most closely adjacent to light receiving lens 4b. Opening 4f is in the form of a slit spaced from optical axis O of light receiving lens 4b by a distance (1) which is measured on the opposite side of the optical axis from light emitting lens 3b. Rear opening 4g is also in the form of a elongated slit, which is substantially located along the optical axis O of light ~receiv;ng lens 4b.~
When prism 4c, together with mask 4d, move in front of }ight receiving lens 4b, i.e., when the camera is in the macro mode, a first lens group of the photographic lens is fed forwardly by a constant displacement, independently of the displacement of the lens which is fed forwardly during the normal photographic mode by the automatic focusing device. As best seen in Figs. 9 and 10, when prism 4c is located in front of light receiving lens 4b, the range of 13~0 ~2 P5713S01 ~ - 23 measurement of the distance of the subject can be shifted to the macro mode range. Prism 4c serves to move light incident thereon in a parallel fashion, over a displacement (l) in the direction of the base length, so that base length L can be optically extended to equal the distance (L+l).
Assuming that the angle and the refractive index of prism 4c are ~ l~ and n, respectively, and that the parallel displacement of light by prism 4c is represented by the distance (1), deviation t2 of the image on position detecting element 4a, as viewed with respect to the subject distance U2, can be obtained as hereinafter detailed.
The incident angle of light on the plane of prism 4c which is adjacent to the ~ubject is provided by the following equation:
alphal=tan l {(L+l)/(U2-f-d)) + ~ l This equation indicates that the base length of the triangulation distance measuring device is extended from L
to (L+l) by the insertion of prism 4c in front of the light receiving lens 4b. The refraction angle betal of light which is incident upon a prism having an angle ~ 1~ which light is incident upon the prism at an incident angle of alphal, is calculated in accordance with the following equation:
betal = alphal- ~ l+sin _l~nsin { ~ l-sin (alphal/n))], and, therefore: ~ l = alphal ~ ~ l ~ betal-Accordingly, deviation t2 of the image on positiondetecting sensor 4a is equal to f x tan ~ l' i.e., t2 = F x ~, , , ~ i ~
tan O
The subject distance Umf2 which is obtained when light coincident with the optical axis of light receiving lens 4b intersects the optical axis of light emitting lens 3b is yielded by using the following equation, provided that the thickness of prism 4c is negligible:
Umf2=(L+l)/tan (sin l(n x sin ~ 1} +f+d.
Table 2 hereinafter illustrates the results of the calculations in which the distance measuring device of Figs.
l3304a2 P5713S01 ~ 24 10 and 11 has been applied to a photographing lens satisfying the same basic criteria as those mentioned with respect to the embodiment of Figure 14, i.e., namely that:
(a) The photographic lens is a 2-group lens;
(b)fl, i.e., the focal length of the first group, equals 24.68 mm;
(c) HH, i.e., the principal point distance, equals 7.02mm;
(d) delta, i.e., the distance between the focal length of the first lens group and the focal length of the zoom lens, equals 30.04 mm;
(e) d, i.e., the distance between the film plane and the focal plane of the light receiving lens, equals 6.292mm;
(f) the displacement of the first lens group in the macro setting equals 0.5502mm;
(g) L, i.e., the base length of the distance measuring device, equals 30mm;
(h) f, i.e., the focal length of the light receiving lens, equals 20mm;
i.e., the angle of prism 4c, equals 3.39;
(j) n, i.e., the refraction index of the ~
prism, equals 1.483; ~ ! -(k) (1), i.e., the distance representing the parallel displacement of the rays of :~ light, equals 3.39mm;
;~ (1) the range of measurement of the distance of the subject which can be ~
measured equals 0.973m- infinity; ~;
(m) the number of steps of forward feeding movement of the zoom lens is i8;
~3304~2 P5713Sol - 25 (n) the range of 0.973m- 6m is divided into 17 steps; and (o) the photographic range of 0.973m- 6m is shifted into the range of 0.580m-1.020m.
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POSXTIONS OF IMAGES ON THE POSITION DETECTING SENSOR AT
DIFFERENT SUBJECT DISTANCES WITH THE MACRO COMPENSATION
ELEMENT OF FIGURES 9, lo AND 11 STEP NO. U (m) U 2 (m) t(mm) _2(mm) -2 t (mm) 17-18 6.000 1.020 0.1004 0.1005 o.OOOl 17 5.154 0.996 0.1170 0.1171 O.Oool 16 4.027 0.951 0.1500 0.1500 o 1015 3.310 o.9ll 0.1827 0.1827 o 14 2.814 0.875 0.2153 0.2152 -o.oool 13 2.450 0.841 0.2476 0.2475 -O.oool 12 2;172 0.810 0.2797 o.2796 -0.0001 11 1.952 0.782 0.3115 0.3115 0 1510 1.775 0.756 0.3432 0.3432 o 9 1.628 0.732 0.3747 0.3746 -0.0001 8 1.504 0.709 0.4059 0.4059 o
7 1~399 0.688 0.4369 0.4369 0 6 1.309 0.668 0.4678 0.4677 -0.0001 20 5 1.230 0.650 0.4984 0.4984 0 4 1.161 0.633 0.5288 0.5288 o 3 1.100 0.616 0.5591 0.5591 0 2 1.045 0.601 0.5891 0.5891 0 1 0.99O 0.587 0.6189 q.6190 0.0001 - 250-1 0.973 0.580 0.6338 0.6338 Q -~
U m~2=1 283m ~ ;
It should be clearly understood from Table 2 that the deviation of the~images on the position detecting sensor 4a at different steps between the normal photographic mode and the macro mode will therefore be within +/- O.OOOlmm. This is represented by the value t2-t in the last column on page 2. Accordingly, it is possible to almost completely form images at the focal point by adjusting the photographic ~-optical system in accordance with the output of the position detecting sensor 4a. Table 2 illustrates that prism 4c can ~:`
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--~ 1330A1~2 ' optically extend the base length, which is nonnally 30~1m in a normal photography camera mode, in the macro mode so that it will be 1.113 times the normal base length, i.e., the base length will be 33.3smm when the camera is in its macro 5 mode; as a result, displacement of position detecting sensor 4a can be increased by a factor of 1.113.
In operation, it is possible to automatically focus the camera within any zooming range, including the macro setting of the camera, by actuating' previously discussed shutter 10 unit 23 in accordance with the output signals, i.e., the measurement data, which are sent by position detecting sensor 4a. Specifically, whën driving pulses are applied to t,he pulse motor of shutter unit 23 in accordance with the measurement data which has been received from detecting 15 sensor 4a, a lens actuating or feeding lever 23a, as seen in Fig. 8, rotates over an angle corresponding to the driving pulses which it has received in order to rotate front lens frame 24 together with it. As a result of this rotation of front lens ~rame 24, the front lens element group Ll is 20 moved along the direction of the photographing optical axis, via the action of helicoid 25, in'order that focusing of the photographic lens assembly will be automatically effected.
Lens harriel b?oclc 1 rotates cam ring 14 when zooming motor 5 is driven. Rotation of ca,m ring 14 ~:auses roller 17 25 of front frame 16 to engage the extreme macro position fixing section 20g of cam groove 20, i.e., roller moves into section 20g from macro transfer section 20f of cam ring 14, ~; so that front lens element group Ll will be fed further ; forwardly to mo,ve intojposition for macro mode operation of 30 the camera.
As clearly seen in Figs. 1 and 2, macro compensating element 4e is secured to a free end of a flexible ' compensation or correcting flag 42, which is pivoted at its base end to camera base plate 6 via a shaft 41 located below 35 light receiver 4. Flag 42 is normally retained in a ~ substantially straight position when no external force is " ~ ' ~ ~3304~2 applied to the flag, and is elastically deformed whenever an external force is applied to the flag. Also attached to shaft 41, and having a pointed surface directed away from the flag, is a projection 43, which can either be formed integrally with the flag and attached to shaft 41, or which can be formed separately from the flat and a~tached to shaft 41 at a central bore of the projection. The macro compensating element 4e is continuously and rotatably biased into a retracted position in which it is retracted away from the optical axis of light receiver 4 by a tension spring 46, as illustrated in Fig. 2. As saen in ~ig. 2 and (bette~) in Fig. 1, cam ring 14 includes a projection 44 on sector gear 15 (or on the cam ring) which engages flag projection 43 in order to move macro compensating optical element 4e into the optical axis of the distance measuring device and in front of light receiver 4 whenever the cam ring 14 rotates to the macro setting position. As shown in Fig. 1, a substantially semi-cylindrical recess (or other recessconfiguration) 44a is provided on the gear 15 adjacent to the camming surface or projection 44. This recess is provided to facilitate the pivoting or rotating motion of flag projection 43 as the cam ring rotates. In other words, recess 44a is necessary to facilitate turning movement of the projection and hence pivoting or rotating motion of optical element 4e into the position illustrated in dotted lines in Fig. 2, in front of light receiver 4. Alternately, ring 14 or gear 15 can be formed with a smaller diameter in order to provide sufficient pivoting room for projection 43. Camming projection 44, which effects, via its engagement with projection 43, rotational or advancing motion of macro compensating optical element 4e, is positioned and configured so that the optical element will be rotated slightly past the position in which the element would be aligned with the optical axis of light receiver 4. However, the flat end of the element 4e which most closely approaches support plate 6e which is integrally attached to base 6, is .
~ ~33a4~2 adapted to engage the left hand side surface of plate 6e (as seen in Fig. 2) via a shock absorbing nub or button 4~, shown in both Figs. 1 and 2. Accordingly, over rotational motion of element 4e which is effected by projection 44 will be absorbed both by the flexlble flag 42, wh~ch is formed from a resilient plastic, rubber, or other resilient material and/or the provision of nub 4g, which will serve to engage the side edge of plate 6e.
Thus, when cam ring 14 moves into the macro setting position, the macro compensating optical element 4e can automatically be brought into alignment with the optical axis of the light receiver, into a position in front of the light receiver, in order to optically extend the base length between the light emitter 3 and the light receiver 4.
C. Finder Optical System The finder optical system is best illustrated in Figures 1 and 15-20.
The finder optical system is designed not only to vary magnification between a wide field of view with a small magnification, and a narrow field of view with a large magnification, in accordance with the zooming operation of the photographing lens system, but also to provide a field of view having less parallax when the camera is used in its macro mode.
~ 25 One significant feature of the present invention is -~ that the finder optical system is capable of automatically moving in association with both zooming of the photographic lens and movement of the photographic lens into a~ macro setting in order to satisfy all of the requirements of a finder system as set forth immediately above. While conventional finders appear to provide a plurality of bright frames with different sizes in the field of view of the finder, this is not a satisfactory solution to the problems ~ noted above, e.g., the use of such frames alone will not minimize parallax in a macro operatlonal mode such as that used in the present camera.
~. ~
-~30~02 P5713Sol ~ 30 Under such circumstances, and in accordance with the prese~t invention, a finder optical device is p' ovided in a lens shutter type of camera having a zoom lens which essentially comprises an improved inverted Galilean finder.
In other words, the finder optical system of the present invention includes a first lens group having a negative refracting power which comprises a positive lens in the form of a fixed lens ~3 and a movable negative lens in the form of a variable power lens L5, a second lens group having a negative lens L4-l which is one lens in a fixed eyepiece group L4, and a third lens group having a positive refracting power lens L4-2 which defines a second lens in the fixed eyepiece lens group L4. A prism Pl is adapted to be selectively moved between the positive lens L3 and the negative lens L5 of the first lens group in order to refract rays of light towards the optical axis. The negative lens L5 of the first group can be displaced from a position adjacent,to the subject towards a position which is adjacent to a photographer's eye in order to vary the magnification from a wide field of view having a small magnification to a narrow field of view having a large magnification. Prism Pl, selectively brought into alignment with the optical axis of the finder optical system, serves to decrease the parallax when the photographic optical system is in the macro setting and when the negative lens LS of the first group moves closest to the eye of the photographer along the optical axis.
The bright'frames which are illustrated in dashed lines in Fig. 52 define the photographing ranges and are applied to the face of the lens of the third group which is closest to the subject, i.e., on the left hand face A of stationary eyepiece lens L4-2 in Figs. 15A, 16A, 17A, 18A, l9A and 20A, ~ respectively. These yellow frames, which are placed on lens ,~ surface A comprise a central autofocus spot ~to be positioned on the main portion of a photographic subject), a large picture area frame (for ordinary photography using the P5713SOl - 31 zoom lens), and a smaller parallax correction frame (used since the picture area will slightly narrow in the macro mode). Further, face B of the second lens group L4-l which is most closely adjacent to the eye of a photographer, is formed from a semi-transparent material, so that a virtual image of the bri~ht frames which are formed by the semi-transparent face can be enlarged and viewed through the positive lens of the third lens group L4-2.
The yellow bright frames are positioned on the front surface of the fixed eye piece lens L4-2 by, e.g., sputtering; and the rear surface of the eyepiece lens element L4-1, i.e., surface B or r6, can be in the form of a semi-transmissive, semi-reflective concave mirror. Light rays emitted from (i.e., reflected by) the bright frames are reflected rearwardly by concave surface R6 and are focused on the viewers eye. The eye recognizes enlarged false images of the frames in a position in the far foreground, which images are formed via the optical effect of lenses L4-l and L4-2. ;~
The negative lens L5 of the first group is movable, as noted above, so that it will move from a position which it is located adjacent to the subject into a position in whicn it is more closely adjacent to the eye of a photographer, in order to increase the focal length of the photographic optical system during the normal zooming operation, so that magnification can be varied from a wide field of view having a small magnification to a narrow field of view having a large magnification. Whén~ a picture is taken in the macro (beyond telephoto) mode with a narrow field of view and large magnification, a prism is inserted between the movable lens L5 and stationary lens L3 in order to decrease ~; parallax, so that light will be refracted towards the location of the axis of the photographic optical system.
Enough room is provided for the prism to pivot upwardly for macro focusing, i.e., thereby creating a need to move ;: ~ the lens L5 a relatively large distance, as shown in Figs.
;~ :
~ ,.
l330~a2 16A, 17A, l9A and 20A, in order to insert the prism Pl therein in a pivotable or rotatable fashion. -`
On advantage of the system is that it incorporates only a single moving lens L5, rather than zooming a plurality of lenses or the entire finder optical lens system and naving to thereafter compensate for such zooming movement of all of the lenses. This serves to simplify the zooming cam plate structure, as movement of only a single lens will suffice to change the magnification of finder image.
The fixed viewing frames, as shown in Fig. 52, are provided in order to avoid having to make a viewing ad~ustment. The two rear eyepiece lens groups L4-1 and L4-2 which include the frames are fixed, and the curvatures of their respective surfaces are controlled so that the --reflected frames will have a desired magnification which is compatible with the image magnification over the entire range of zooming operation of the photographic lens. ~ -The apex angle or angles of the selectively insertable prism are defined by the resultant angles in the horizontal and vertical directions, in accordance with the positions of the optical finder system and the photographic optical ~ -system. The prism can be a single wedge prism, or can be a double wedge shaped prism, as illust~ated in Figs. 53A, 53B, and 53C, which illustrate a double wedge prism Pl' which is advantageous because it is capable of bending light downwardly and rightwardly towards the optical axis of the ~ -photographic optical system.
As illustrated in Figs. 53, double we`dge prism Pl has a surface which increases, when viewed from the top in the 30 direction of axrow A (see Figs. 53A and 53B) and which also ~-;
increases from the left hand to the right hand direction, as -~-viewed from the front of the camera from the photographing optical axis, and as shown by arrow B (Figs. 53A and 53C). -~
In the example illustrated, the angle ~ H can be 2.8, 35 the angle ~ V can be 4.2, the angle ~ H' could be `
~4.2, and the angle ~ V' could be 5Ø
$~ -r t33~2 PS713Sol 33 The wedge prism is adapted to be inserted between the first convex single lens element L3 and the movable concave single lens element L5 in a rotatable fashion. This permits the finder unit to be made compactly and allows the prism to be inserted between these two elements. The viewing distance of the false image of an object and the bright frames remain stationary throughout the zooming range of the photographic lens, and parallax compensation is provided by moving the prism between the lenses in the macro or close up lo picture taking mode. The viewing magnification or size of the bright frame images is also maintained constant throughout the zooming range of the ~hotographic lens, as well as in the macro setting, due to the placement of the bright frames on the stationary lens element L4-2. The distance between the eye of a viewer and the image distance, i.e., the diopter of the finder, virtually does not vary, because the zooming concave lens element moves over an image magni~ication of lx, or, i.e., is life size.
Parallax compensation in the macro or close up picture taking mode is effected by positioning the wedge prism between the lens elements, as well as by the use of the compensation framing marks illustrated in Fig. 52 (which is the normal means of parallax compensation in a close focusing mode in viewfinder type cameras). The edges of the wedge prism are tinted green to highlight the frame that illustrates the photographic area in the macro or close-up mode.
Theoretically, the prism could be located in front of the first lens group; however, by so arranging the prism, it would increase the overall size of the finder optical system. The prism cannot, however, be located between the second and third lens groups, because if it were inserted between these groups, the positions of the bright frame and of the virtual image of the subject could vary in accordance with movement of the prism. However, when the prism is retractably inserted between the positive lens and the ' '~
- ' 133~ ~2 P5713SOl - 34 negative lens of the first lens group, as is the case in the present invention, the prism is free from such problems, and virtually no change in dioptric power to the virtual image of the subject will occur.
Several examples of a finder optical system formed in accordance with the present invention will now be discussed:
Example Figs. 15A, 15B, 16A, 16B and 17A, 173 illustrate different positions of a first embodiment of a finder device formed in accordance with the present invention. Fig. 15A
illustrates the finder optical system when it is providing a wide field of view with a small magnification; Fig. 16A
illustrates this finder system when it is providing a narrow field of view with a large magnification; and Fig. 17A
illustrates the finder system whenever it is providing a narrow field of view with large magnification and when it is in the macro mode, respectively. Figs. 15B, 16B and 17B, respectively, are views illustrating the aberrations of the finder lens system in the positior~s of Figs. 15A, 16A and 17A, respectively.
This finder optical system includes a positive single lens L3 and a negative single lens 15 which form the first lens group,- a negative single eyepiece lens L4-1 which forms the second lens group; and a positive single eyepiece lens L4-2 forming the third lens group; together with a selectively positionable prism Pl. Among all of these optical elements, only the negative single lens L5 is movable along the direction of the optical axis, and prism Pl is selectively movable into alignment with this optical axis; all of the other lenses remain stationary.
Tables 3 and 4 which follow illustrate the curvatures r, the distances d, the refractive indexes Nd and Abbe's numbers \~ d of the opposite side faces of optical elements L3, L5, L4-1, L4-2, and Pl (Table 4 only), respectively. As shown in the following tables 3 and 4, each of features r, d, Nd and `f d are designated by any one of numbers 1-8 and ~ .
:
:: .
~ 3 ~ 2 1-10, respectively, as viewed from the side of the positive single lens L3 which is closest to the subject, i.e., from the left hand portion of the figures towards the eye or right hand portion of the figures.
Table 3 represents the position of the lens when it is in its wide field of view, small ~agnification position (0.38x) and when it is in its narrow field of ~iew, large magnification position (0.70x), and Table 4 illustrates the position of the lens when it is in the macro mode. The apex angles of prism Pl used in this mode, when it is in a double wedge prism are, e.g., 2.8 in horizontal section and 4.2 in vertical section. -The bright frame which defines the picture taking range is applied to surface A of the positive single lens L4-2 of the third lens group which is most closely adjacent to the subject being photographed, and the surface B of the negative single lens L4-1 of the second lens group which is most closely adjacent to the photographers eye is semi-transparent. As a result, a virtual image of the bright frame applied to face A of the positive single lens L4-2 is formed and reflected by face ~, and is thereafter enlarged and viewed through the positive single lens L4-2, again as discussed previously.
` ' ' ` ' ' / , . ~ ~ .
~ . /
~: ' ~33a~
;: ~
P5713S01 ~ 36 No. r d Nd ~_ 1 30.800 4.50 1.49186 57.4 2 -2221.231 0.50 (0.38x) -15.80(0.70x) 3 55.555 1.21 1.49186 57.4 4 9.680 18.30(0.38x) ~
3.00 (0.70x)
U m~2=1 283m ~ ;
It should be clearly understood from Table 2 that the deviation of the~images on the position detecting sensor 4a at different steps between the normal photographic mode and the macro mode will therefore be within +/- O.OOOlmm. This is represented by the value t2-t in the last column on page 2. Accordingly, it is possible to almost completely form images at the focal point by adjusting the photographic ~-optical system in accordance with the output of the position detecting sensor 4a. Table 2 illustrates that prism 4c can ~:`
~ . .
, ,~ ..
: ' ' .
~"`,if:f}};
--~ 1330A1~2 ' optically extend the base length, which is nonnally 30~1m in a normal photography camera mode, in the macro mode so that it will be 1.113 times the normal base length, i.e., the base length will be 33.3smm when the camera is in its macro 5 mode; as a result, displacement of position detecting sensor 4a can be increased by a factor of 1.113.
In operation, it is possible to automatically focus the camera within any zooming range, including the macro setting of the camera, by actuating' previously discussed shutter 10 unit 23 in accordance with the output signals, i.e., the measurement data, which are sent by position detecting sensor 4a. Specifically, whën driving pulses are applied to t,he pulse motor of shutter unit 23 in accordance with the measurement data which has been received from detecting 15 sensor 4a, a lens actuating or feeding lever 23a, as seen in Fig. 8, rotates over an angle corresponding to the driving pulses which it has received in order to rotate front lens frame 24 together with it. As a result of this rotation of front lens ~rame 24, the front lens element group Ll is 20 moved along the direction of the photographing optical axis, via the action of helicoid 25, in'order that focusing of the photographic lens assembly will be automatically effected.
Lens harriel b?oclc 1 rotates cam ring 14 when zooming motor 5 is driven. Rotation of ca,m ring 14 ~:auses roller 17 25 of front frame 16 to engage the extreme macro position fixing section 20g of cam groove 20, i.e., roller moves into section 20g from macro transfer section 20f of cam ring 14, ~; so that front lens element group Ll will be fed further ; forwardly to mo,ve intojposition for macro mode operation of 30 the camera.
As clearly seen in Figs. 1 and 2, macro compensating element 4e is secured to a free end of a flexible ' compensation or correcting flag 42, which is pivoted at its base end to camera base plate 6 via a shaft 41 located below 35 light receiver 4. Flag 42 is normally retained in a ~ substantially straight position when no external force is " ~ ' ~ ~3304~2 applied to the flag, and is elastically deformed whenever an external force is applied to the flag. Also attached to shaft 41, and having a pointed surface directed away from the flag, is a projection 43, which can either be formed integrally with the flag and attached to shaft 41, or which can be formed separately from the flat and a~tached to shaft 41 at a central bore of the projection. The macro compensating element 4e is continuously and rotatably biased into a retracted position in which it is retracted away from the optical axis of light receiver 4 by a tension spring 46, as illustrated in Fig. 2. As saen in ~ig. 2 and (bette~) in Fig. 1, cam ring 14 includes a projection 44 on sector gear 15 (or on the cam ring) which engages flag projection 43 in order to move macro compensating optical element 4e into the optical axis of the distance measuring device and in front of light receiver 4 whenever the cam ring 14 rotates to the macro setting position. As shown in Fig. 1, a substantially semi-cylindrical recess (or other recessconfiguration) 44a is provided on the gear 15 adjacent to the camming surface or projection 44. This recess is provided to facilitate the pivoting or rotating motion of flag projection 43 as the cam ring rotates. In other words, recess 44a is necessary to facilitate turning movement of the projection and hence pivoting or rotating motion of optical element 4e into the position illustrated in dotted lines in Fig. 2, in front of light receiver 4. Alternately, ring 14 or gear 15 can be formed with a smaller diameter in order to provide sufficient pivoting room for projection 43. Camming projection 44, which effects, via its engagement with projection 43, rotational or advancing motion of macro compensating optical element 4e, is positioned and configured so that the optical element will be rotated slightly past the position in which the element would be aligned with the optical axis of light receiver 4. However, the flat end of the element 4e which most closely approaches support plate 6e which is integrally attached to base 6, is .
~ ~33a4~2 adapted to engage the left hand side surface of plate 6e (as seen in Fig. 2) via a shock absorbing nub or button 4~, shown in both Figs. 1 and 2. Accordingly, over rotational motion of element 4e which is effected by projection 44 will be absorbed both by the flexlble flag 42, wh~ch is formed from a resilient plastic, rubber, or other resilient material and/or the provision of nub 4g, which will serve to engage the side edge of plate 6e.
Thus, when cam ring 14 moves into the macro setting position, the macro compensating optical element 4e can automatically be brought into alignment with the optical axis of the light receiver, into a position in front of the light receiver, in order to optically extend the base length between the light emitter 3 and the light receiver 4.
C. Finder Optical System The finder optical system is best illustrated in Figures 1 and 15-20.
The finder optical system is designed not only to vary magnification between a wide field of view with a small magnification, and a narrow field of view with a large magnification, in accordance with the zooming operation of the photographing lens system, but also to provide a field of view having less parallax when the camera is used in its macro mode.
~ 25 One significant feature of the present invention is -~ that the finder optical system is capable of automatically moving in association with both zooming of the photographic lens and movement of the photographic lens into a~ macro setting in order to satisfy all of the requirements of a finder system as set forth immediately above. While conventional finders appear to provide a plurality of bright frames with different sizes in the field of view of the finder, this is not a satisfactory solution to the problems ~ noted above, e.g., the use of such frames alone will not minimize parallax in a macro operatlonal mode such as that used in the present camera.
~. ~
-~30~02 P5713Sol ~ 30 Under such circumstances, and in accordance with the prese~t invention, a finder optical device is p' ovided in a lens shutter type of camera having a zoom lens which essentially comprises an improved inverted Galilean finder.
In other words, the finder optical system of the present invention includes a first lens group having a negative refracting power which comprises a positive lens in the form of a fixed lens ~3 and a movable negative lens in the form of a variable power lens L5, a second lens group having a negative lens L4-l which is one lens in a fixed eyepiece group L4, and a third lens group having a positive refracting power lens L4-2 which defines a second lens in the fixed eyepiece lens group L4. A prism Pl is adapted to be selectively moved between the positive lens L3 and the negative lens L5 of the first lens group in order to refract rays of light towards the optical axis. The negative lens L5 of the first group can be displaced from a position adjacent,to the subject towards a position which is adjacent to a photographer's eye in order to vary the magnification from a wide field of view having a small magnification to a narrow field of view having a large magnification. Prism Pl, selectively brought into alignment with the optical axis of the finder optical system, serves to decrease the parallax when the photographic optical system is in the macro setting and when the negative lens LS of the first group moves closest to the eye of the photographer along the optical axis.
The bright'frames which are illustrated in dashed lines in Fig. 52 define the photographing ranges and are applied to the face of the lens of the third group which is closest to the subject, i.e., on the left hand face A of stationary eyepiece lens L4-2 in Figs. 15A, 16A, 17A, 18A, l9A and 20A, ~ respectively. These yellow frames, which are placed on lens ,~ surface A comprise a central autofocus spot ~to be positioned on the main portion of a photographic subject), a large picture area frame (for ordinary photography using the P5713SOl - 31 zoom lens), and a smaller parallax correction frame (used since the picture area will slightly narrow in the macro mode). Further, face B of the second lens group L4-l which is most closely adjacent to the eye of a photographer, is formed from a semi-transparent material, so that a virtual image of the bri~ht frames which are formed by the semi-transparent face can be enlarged and viewed through the positive lens of the third lens group L4-2.
The yellow bright frames are positioned on the front surface of the fixed eye piece lens L4-2 by, e.g., sputtering; and the rear surface of the eyepiece lens element L4-1, i.e., surface B or r6, can be in the form of a semi-transmissive, semi-reflective concave mirror. Light rays emitted from (i.e., reflected by) the bright frames are reflected rearwardly by concave surface R6 and are focused on the viewers eye. The eye recognizes enlarged false images of the frames in a position in the far foreground, which images are formed via the optical effect of lenses L4-l and L4-2. ;~
The negative lens L5 of the first group is movable, as noted above, so that it will move from a position which it is located adjacent to the subject into a position in whicn it is more closely adjacent to the eye of a photographer, in order to increase the focal length of the photographic optical system during the normal zooming operation, so that magnification can be varied from a wide field of view having a small magnification to a narrow field of view having a large magnification. Whén~ a picture is taken in the macro (beyond telephoto) mode with a narrow field of view and large magnification, a prism is inserted between the movable lens L5 and stationary lens L3 in order to decrease ~; parallax, so that light will be refracted towards the location of the axis of the photographic optical system.
Enough room is provided for the prism to pivot upwardly for macro focusing, i.e., thereby creating a need to move ;: ~ the lens L5 a relatively large distance, as shown in Figs.
;~ :
~ ,.
l330~a2 16A, 17A, l9A and 20A, in order to insert the prism Pl therein in a pivotable or rotatable fashion. -`
On advantage of the system is that it incorporates only a single moving lens L5, rather than zooming a plurality of lenses or the entire finder optical lens system and naving to thereafter compensate for such zooming movement of all of the lenses. This serves to simplify the zooming cam plate structure, as movement of only a single lens will suffice to change the magnification of finder image.
The fixed viewing frames, as shown in Fig. 52, are provided in order to avoid having to make a viewing ad~ustment. The two rear eyepiece lens groups L4-1 and L4-2 which include the frames are fixed, and the curvatures of their respective surfaces are controlled so that the --reflected frames will have a desired magnification which is compatible with the image magnification over the entire range of zooming operation of the photographic lens. ~ -The apex angle or angles of the selectively insertable prism are defined by the resultant angles in the horizontal and vertical directions, in accordance with the positions of the optical finder system and the photographic optical ~ -system. The prism can be a single wedge prism, or can be a double wedge shaped prism, as illust~ated in Figs. 53A, 53B, and 53C, which illustrate a double wedge prism Pl' which is advantageous because it is capable of bending light downwardly and rightwardly towards the optical axis of the ~ -photographic optical system.
As illustrated in Figs. 53, double we`dge prism Pl has a surface which increases, when viewed from the top in the 30 direction of axrow A (see Figs. 53A and 53B) and which also ~-;
increases from the left hand to the right hand direction, as -~-viewed from the front of the camera from the photographing optical axis, and as shown by arrow B (Figs. 53A and 53C). -~
In the example illustrated, the angle ~ H can be 2.8, 35 the angle ~ V can be 4.2, the angle ~ H' could be `
~4.2, and the angle ~ V' could be 5Ø
$~ -r t33~2 PS713Sol 33 The wedge prism is adapted to be inserted between the first convex single lens element L3 and the movable concave single lens element L5 in a rotatable fashion. This permits the finder unit to be made compactly and allows the prism to be inserted between these two elements. The viewing distance of the false image of an object and the bright frames remain stationary throughout the zooming range of the photographic lens, and parallax compensation is provided by moving the prism between the lenses in the macro or close up lo picture taking mode. The viewing magnification or size of the bright frame images is also maintained constant throughout the zooming range of the ~hotographic lens, as well as in the macro setting, due to the placement of the bright frames on the stationary lens element L4-2. The distance between the eye of a viewer and the image distance, i.e., the diopter of the finder, virtually does not vary, because the zooming concave lens element moves over an image magni~ication of lx, or, i.e., is life size.
Parallax compensation in the macro or close up picture taking mode is effected by positioning the wedge prism between the lens elements, as well as by the use of the compensation framing marks illustrated in Fig. 52 (which is the normal means of parallax compensation in a close focusing mode in viewfinder type cameras). The edges of the wedge prism are tinted green to highlight the frame that illustrates the photographic area in the macro or close-up mode.
Theoretically, the prism could be located in front of the first lens group; however, by so arranging the prism, it would increase the overall size of the finder optical system. The prism cannot, however, be located between the second and third lens groups, because if it were inserted between these groups, the positions of the bright frame and of the virtual image of the subject could vary in accordance with movement of the prism. However, when the prism is retractably inserted between the positive lens and the ' '~
- ' 133~ ~2 P5713SOl - 34 negative lens of the first lens group, as is the case in the present invention, the prism is free from such problems, and virtually no change in dioptric power to the virtual image of the subject will occur.
Several examples of a finder optical system formed in accordance with the present invention will now be discussed:
Example Figs. 15A, 15B, 16A, 16B and 17A, 173 illustrate different positions of a first embodiment of a finder device formed in accordance with the present invention. Fig. 15A
illustrates the finder optical system when it is providing a wide field of view with a small magnification; Fig. 16A
illustrates this finder system when it is providing a narrow field of view with a large magnification; and Fig. 17A
illustrates the finder system whenever it is providing a narrow field of view with large magnification and when it is in the macro mode, respectively. Figs. 15B, 16B and 17B, respectively, are views illustrating the aberrations of the finder lens system in the positior~s of Figs. 15A, 16A and 17A, respectively.
This finder optical system includes a positive single lens L3 and a negative single lens 15 which form the first lens group,- a negative single eyepiece lens L4-1 which forms the second lens group; and a positive single eyepiece lens L4-2 forming the third lens group; together with a selectively positionable prism Pl. Among all of these optical elements, only the negative single lens L5 is movable along the direction of the optical axis, and prism Pl is selectively movable into alignment with this optical axis; all of the other lenses remain stationary.
Tables 3 and 4 which follow illustrate the curvatures r, the distances d, the refractive indexes Nd and Abbe's numbers \~ d of the opposite side faces of optical elements L3, L5, L4-1, L4-2, and Pl (Table 4 only), respectively. As shown in the following tables 3 and 4, each of features r, d, Nd and `f d are designated by any one of numbers 1-8 and ~ .
:
:: .
~ 3 ~ 2 1-10, respectively, as viewed from the side of the positive single lens L3 which is closest to the subject, i.e., from the left hand portion of the figures towards the eye or right hand portion of the figures.
Table 3 represents the position of the lens when it is in its wide field of view, small ~agnification position (0.38x) and when it is in its narrow field of ~iew, large magnification position (0.70x), and Table 4 illustrates the position of the lens when it is in the macro mode. The apex angles of prism Pl used in this mode, when it is in a double wedge prism are, e.g., 2.8 in horizontal section and 4.2 in vertical section. -The bright frame which defines the picture taking range is applied to surface A of the positive single lens L4-2 of the third lens group which is most closely adjacent to the subject being photographed, and the surface B of the negative single lens L4-1 of the second lens group which is most closely adjacent to the photographers eye is semi-transparent. As a result, a virtual image of the bright frame applied to face A of the positive single lens L4-2 is formed and reflected by face ~, and is thereafter enlarged and viewed through the positive single lens L4-2, again as discussed previously.
` ' ' ` ' ' / , . ~ ~ .
~ . /
~: ' ~33a~
;: ~
P5713S01 ~ 36 No. r d Nd ~_ 1 30.800 4.50 1.49186 57.4 2 -2221.231 0.50 (0.38x) -15.80(0.70x) 3 55.555 1.21 1.49186 57.4 4 9.680 18.30(0.38x) ~
3.00 (0.70x)
-8.327 1.00 1.60311 60.7 6 500845 7.33 7 cX~ 2.23 1.60311 60.7 ~ -8 -11.780 15 No. r d Nd ~d -~
1 30.800 4.50 1.49186 57.4 2 -2221.231 1.70 3 C~ 2.70 1.49186 57.4 4 cX~ 11.40 ` ~ ~
55.555 1.21 1.49186 57.4 ~ ~;
6 9.680 3.00 7 -8.327 1.00 1.60311 60.7 8 50.845 7.33 ~ ~ -cX~ 2.23 1.60311 60.7 -11.780 ExamPle 2 Fig. 18A illustrates a second embodiment of the finder optical system in its wide field of view, small magnification pasitilon; Fig~ l9A illustrates this embodiment in its narrow field of view, large magnification position;
and Fig. 20A illustrates this finder optical assembly ~; embodiment in its narrow field of view, large magnification, macro mode position; and Figs. 18B, l9B and 20B, respectively, illustrate the aberrations in the finder lens system in the three different positions illustrated in Figs.
18A, 19A and 20A, respectively. In this second embodiment -. :
,' ~;~ .
! ~ ',' ( '' 33~ ~2 P~713S01 - 37 of the finder optical device, the lens system is different from that in the first embodiment as discussed in example l, insofar as the third lens group comprises two lenses in the form of positive lenses L4-2 and L4-3.
Tables 5 and 6 illustrate the curvatures r, distances d, refractive indexes Nd, and Abbe's numbers v~d, for all of the elements of the second embodiment of the finder lens system, which tables are similar to Tables 3 and 4 previously discussed with respect to the first embodiment of the finder optical system. In Table 5, which represents the wide field of view, small magnification (0.35x) position of the system, and the narrow field of view, large magnification (0.648x) position of the system, and in Table 6, which represents the system when in the macro mode, the apex angle of prism Pl is 3.0 in the horizontal direction and 5.0 in the vertical direction, e.g. The bright frame which defines the photographic range is again applied to~ -face A of the positive lens L4-2 of the third group, and face B of the negative single lens L4-l of the second group is again semi-transparent, as in the first embodiment of the finder system.
~. . ' ~ ~ , . ! , /
~ / ,"' : / , ' ~3~0~a2 '`' P5~13Sol - 38 No. r d Nd ~d 1 25.800 4.50 1.4918657.4 2 -190.341 o.so(o.35X) ~
11.89(0.648x) 3 85.200 1.50 1.4918657.4 4 8.081 14.39(0.35x) - ~;
3.00(0.648x) -~
-7.056 1.00 1.6700347.3 6 34.700 5.37 7 cx~ 2.93 1.6031160.7 - -8 -12.538 0.30
1 30.800 4.50 1.49186 57.4 2 -2221.231 1.70 3 C~ 2.70 1.49186 57.4 4 cX~ 11.40 ` ~ ~
55.555 1.21 1.49186 57.4 ~ ~;
6 9.680 3.00 7 -8.327 1.00 1.60311 60.7 8 50.845 7.33 ~ ~ -cX~ 2.23 1.60311 60.7 -11.780 ExamPle 2 Fig. 18A illustrates a second embodiment of the finder optical system in its wide field of view, small magnification pasitilon; Fig~ l9A illustrates this embodiment in its narrow field of view, large magnification position;
and Fig. 20A illustrates this finder optical assembly ~; embodiment in its narrow field of view, large magnification, macro mode position; and Figs. 18B, l9B and 20B, respectively, illustrate the aberrations in the finder lens system in the three different positions illustrated in Figs.
18A, 19A and 20A, respectively. In this second embodiment -. :
,' ~;~ .
! ~ ',' ( '' 33~ ~2 P~713S01 - 37 of the finder optical device, the lens system is different from that in the first embodiment as discussed in example l, insofar as the third lens group comprises two lenses in the form of positive lenses L4-2 and L4-3.
Tables 5 and 6 illustrate the curvatures r, distances d, refractive indexes Nd, and Abbe's numbers v~d, for all of the elements of the second embodiment of the finder lens system, which tables are similar to Tables 3 and 4 previously discussed with respect to the first embodiment of the finder optical system. In Table 5, which represents the wide field of view, small magnification (0.35x) position of the system, and the narrow field of view, large magnification (0.648x) position of the system, and in Table 6, which represents the system when in the macro mode, the apex angle of prism Pl is 3.0 in the horizontal direction and 5.0 in the vertical direction, e.g. The bright frame which defines the photographic range is again applied to~ -face A of the positive lens L4-2 of the third group, and face B of the negative single lens L4-l of the second group is again semi-transparent, as in the first embodiment of the finder system.
~. . ' ~ ~ , . ! , /
~ / ,"' : / , ' ~3~0~a2 '`' P5~13Sol - 38 No. r d Nd ~d 1 25.800 4.50 1.4918657.4 2 -190.341 o.so(o.35X) ~
11.89(0.648x) 3 85.200 1.50 1.4918657.4 4 8.081 14.39(0.35x) - ~;
3.00(0.648x) -~
-7.056 1.00 1.6700347.3 6 34.700 5.37 7 cx~ 2.93 1.6031160.7 - -8 -12.538 0.30
9 -30.259 2.23 1.4918657.4 lo-15.420 ~ABLE 6 No. r d Nd ~d -1 25.800 4.50 1.4918657.4 --2 -190.341 9.42 3 Cx~ 2.00 1.4918657~4 4 cx~ 0.47 -5 85.200 1:50 1.4918657.4 6 8.081 3.00 7 -7.056 1.00 1.6700347.3 8 34.700 5-37 9 CX~ 2.93 1.6031160.7
10-12.538 0.30 ~-~
11-30.259 2.23 1.4918657.4
12-15.420 As illustratçd jin ~ig. 17A, the finder optical device of the present invention preferably satisfies the following conditions:
(1) 0-3 <dP<0.5;
(2) fl+ <1.8; and (3) 0.45< f3/LD <0.7; wherein:
LD = the total length of the finder;
dP = the distance between the face of lens L3 which is most closely adjacent to prism Pl and the face of lens LS
~ .. . .
~3~ a2 P5713S01 _ 39 which is most closely adjacent to prism Pl;
fl+ = the focal length of the positive lens of the first lens group, and f3 = the focal length of the third lens group.
These criteria are useful and helpful to enable prism Pl to be retractably inserted between the movable lens L3 of the first lens group and the negative lens L5 of the first lens group and ~o minimize the effective diameter of the prism when it is brought into alignment with the optical axis.
The first condition, i.e., 0.3 < dP < 0.5 is based upon the fact that if the value of dP exceeds the noted upper limit, the effective diameter of the l~ns L3 will become large, making it difficult to provide a compact camera as doe~ the present invention; to the contrary, if the value-of dP was <0.3, it would become extremely difficult to smoothly and easily rotate prism Pl so that it would come into alignment with, and be capable of retracting away from, the optical axis in a position between lenses L3 and L5.
Conditions 2 and 3, in which fl+ < 1.8, and 0.45 <
f3/LD <0.7, are provided to minimize the effective diameter of prism Pl. The second criteria noted above is substantially e~uivalent to setting or establishing the focal-length FR of the lens system which is positioned rearwardly of prism Pl when the prism is in alignment with the finder optical axis. Namely, if fl+ exceeds its noted upper limit of 1.8, the effective diameter of the prism will become large, thereby resulting in difficulty in realizing a compact prism and finder.
Condition three is basically equivalent to a ~ requirement for the third lens group located rearwardly of ;~ the prism. Namely, if f3/LD is less than the lower limit of 0.45, the tolerance of the system will become ~uite small.
To the contrary, if the value of f3/LD exceeds the upper ~; 35 limit of 0.7, the effective diameter of the prism will ~ increase.
:: :
:; ~
? ~ ~..'1 S~ 3 3 ~ f~
The values of dP, fl+, and f3/LD in the first and second embodiments above will now be listed; all of these values are set to satisfy conditions 1, 2 and 3 noted above.
First Embodiment Second Embodiment dP 0.45 0.36 fl+ 1.76 1.42 f3/LD 0.56 0~49 D. Drive Mechanism for the Finder and Strobe Devices The driving mechanism which serves to actuate finder 10 optical assembly 8 and strobe assembly 9 is best illustrated in Figs. 21-30.
A mother plate 60 is attached to a finder block 54 which is mounted to base plate 6 via horizontal support plate extension 6b. The mother plate is provided with guide 15 pins 62 integrally attached to the mother plate and which are adapted to fit within a substantially linear guide groove 61 of cam plate 53. Sliding motion of cam plate 53 is in the lateral direction, with respect to the optical axis of the camera, and is restricted by the engagement 20 between guide grooves 61 and guide pins 62; and a guide projection o,r flange 60a (shown in both Figs. 21 and 22) is formed integrally with mother plate 60 and serves to prevent cam plate 53 from floating or moving away from the front ~ surfac:e of the mother plate, particularly at the front end '~ 25 of cam plate 53 where the flange engages the cam plate.
Finder mother plate 60 includes a variable power lens guide groove 63, a deflection prism guide groove 64, and a ~; strobe as'sembly 'guide 'groove 65. ~:achl of these guide grooves extends parallel to the photographic ~ptical axis of 30 the camera. A guide projection 66a of variable finder lens frame 66, which carries the variable finder power lens group L5, is fitted within variable power lens guide groove 63.
Guide projection 67a of deflection prism actuating plate 67 ,~ is slidably positioned or fitted within deflection prism 35 guide groove 64; and guide projection 68a of strobe assembly case 68, which casing has a concave reflector 59 attached ~ 3 3 ~ !~ o ~
P5713Sol - 41 thereto, is fitted or positioned within strobe guide groove 65.
Variable power lens frame 66, deflection prism actuating plate 67, and strobe assembly case 68, together move in a direction which is parallel with respect to the optical axis, along the respective guide grooves. Guide projections 66a, 67a, and 68a are provided with driven pins 69, 70 and 71, which fit within the varia~le power cam groove 55, the parallax compensating cam groove 56, and the strobe cam groove 57, respectively. Accordingly, when cam plate 53 moves laterally, variable power lens frame 66, reflection prism actuating plates 67, and strobe case 68 move along the respective camming grooves 55, 56 and 57.
The sections of the variable power cam groove 55, parallax compensating cam groove 56, and strobe cam groove 57 correspond to sections of zooming cam grooves 20 and 21 of cam ring 14 which have been illustrated in Fig. 7 and described with respect thereto. Specifically, the variable power cam groove 55 includes an extreme wide angle fixing section 55a, a variable power section 55b, and an extreme telephoto fixing section 55c, with the angles 0 1~ 0 2 and ~ 3, respectively, of these three sections corresponding to the similar angles in the cam ring Fig. 7. The parallax compensating cam groove 56 includes a non-projecting section 56a, a projecting movement section 56b, i.e., a forward feed section used for the macro mode, and a projected position fixing section 56c, i.e., an extreme macro fixing section.
Strobe cam groové 57 includes an extreme wide angle !flxing section 57a, a variable power section 57b, an extreme telephoto fixing section 57c, a macro feeding section 57d, and an extreme macro fixing section 57e. The relationship between cam grooves 55, 56 and 57, and zooming cam grooves 20 and 21, is best illustrated in the schematic or pla~ view illustrated in Fig. 44.
The variable power lens frame 66 which supports the variable power lens group L5 is movably supported along -~
~ .
~3~a~a2 guide face 54a of finder block 54 so that frame 66 will hang therefrom, as best illustrated in Fig. 25. The frame can be formed, e.g., from a resin which can slide with respect to the finder block in a substantially frictionless fashion.
When variable power lens frame 66 moves along variable power cam groove 55, magnification of the finder optical system, including lens group L3, eye piece group L4, and variable power lens group L5, will vary, so that the photographic range over which lens barrel block 1 moves will be substantially coincident with the field of view of the finder.
The deflection prism actuating plate 67 is illustrated in Figs. 26-Z8, and is hereinafter described in greater detail.
Deflection prism Pl, which is formed of synthetic resin, is rotatably supported by finder block 54 via two lower opposed prism support pins 74 of the prism. These supporting pins include torsion springs 75 which surround them, with one end of each spring bearing against a respective abutment 76 which abutments are provided along the side faces of defIection prism P1, so that the deflection prism will be continuously biased into a position in which the prism Pl moves into alignment with the optical axis of finder lenses L3-L5. Abutment 76 are located in arc-shaped grooves 79 formed in finder block 54, as best illustrated in Figs. 26-28. The deflection prism actuating plate 67 is held between finder block 54 and a guide plate 80 (see Fig. 25) connected to finder block 54 so that a guide pin 81 which is positioned on the side face of finder block 54 will fit within linear guide groove 82 of guide plate 80.
Position restricting abutments 76 on the prism can be engaged by a stop surface 77 and a guiding surface 78 0 r deflection prism actuating plate 67; further, the prism abutments 76 can come into contact with an end surface of the groove 79 in plate 67 (see Fig. 27). Deflection prism ~,.... ,.;... . ............ ... .........
~33~2 P5713Sol - 43 actuating plate 67 serves to retract the deflection prism from the optical path of lenses L3-L5, against the bias of springs 75, when pin 70 is located in the non-projection section 56a of parallax compensating cam groove 56, insofar as the rotation preventing face 77 of the plate will move into engagement with abutment 76 (see Fig. 26). When pin 70 moves into the projecting movement section 56b, guide surface 78 will move into a butting contact with abutment 76, so that deflection prism Pl will rotate into a position lo in which lt is in alignment with the finder system optical axis with the help of torsion spring 75. During such movement, abutments 76 move on and along face 78, and deflection prism Pl will gradually move into the optical path, as illustrated in Figs. 27 and 28, so that the optical path of th~ finder will be deflected downwardly by prism Pl, as illustrated by the arrow in Fig. 28. As a result of this movement, a subject which is otherwise located below the finder optical axis will come into the camera field of view, and parallax in the macro mode of the camera will be decreased. It is even further decreased, as noted above, when a double wedge prism (Fig. 53A) is used to deflect the finder optical axis downwardly and (rightwardly) towards the optical axis of the photographing optical system.
A guide block 85 is provided along the side face of strobe case 68 and is fitted within a linear guide groove 84 which is parallel to the optical axis of the camera which is formed in guide plate 80, as illustrated in Fig. 30.
~ Further, height adjusting pins 86 (see Figs. 23 and 29) are ;~ provided on the upper and lower faces of strobe case 68 and are adapted to prevent the strobe case from falling ~ downwardly. The strobe case 68 moves along strobe cam - g-oove 57 when cam plate 53 moves in the lateral direction.
Variable power section 57b of strobe cam groove 57 is adapted to move xenon lamp 58 rearwardly, away from Fresnel lens L6. Rearward movement of the xenon lamp 58 causes the illumination angle of light emitted from Fresnel lens L6 to ~ ' ~-~!~ (. '`"
~:3~
P5713Sol _ 44 decrease so as to substantially increase the guide number in accordance with an increase in the focal length. To the contrary, in macro feeding section s7d, the illumination anyle is increased, and the guide number is therefore substantially decreased in the macro mode.
E. Barrier, i.e. Lens CaP Mechanism The barrier lens cap mechanism is best illustrated in Figs. 6, 8 and 31-34.
Barrier mechanism 30 opens and closes a pair of lo barriers 31, (see Fig.8 ) which are located forwardly of the front lens element group Ll of the photographi~ (zooming~
lens system, and which are closed with the ass;stance of rotational force which is produced when cam ring 14 rotates within retracting or storing cam section 20b (see Fig. 7) ln which the lens is collapsed.
Fig. 31 and 32 illustrate a first embodiment of the barrier mechanism. In this embodiment, barrier mechanism 30 opens and closes a photographic opening 22b at the opening of frame 22 via pivoted barrier elements 31. The barrier elements are pivoted, via pins 32, in a substantially symmetrical fashion with respect to the photographic opening 22b of the front lens group support frame 22.
Barriers 31 are disposed in a symmetrically opposite position with respect to each other and include respective barrier plate portions 3la which can be moved so as to project into the path of the photographing optical axis, as well as driving arm portions 31b which are positioned on the opposite sides of the barriers from the side on which barrier plate portions 31a are located. Driving arm ; 30 portions 31b are generally attached to the inner front surface of barrier assembly 30 by pins 33. Driving arm portions 31b include pins 33 which are engaged by operational arms 34a of opening and closing springs 34, as shown in Figs. 31 and 32. In other words, pins 33 are ;~ 35 adapted to slide within, and/or be moved by, respective ~; fork-shaped end portions of the driving arms.
~33~4a2 Opening and closing springs 34 are comprised, e.g., of molded synthetic resin and include the Y-shaped spring arm 34b and driving arm portions 34c, in addition to the fork-shaped operational arms 34a which engage pins 33. Each of the springs is pivoted to the barrier mechanism 30 by a respective pin 35. Spring arms 34b bear against the inner wall of the front lens group support frame 22 in order to continuously bias barrier plate portions 3la, via operational arm 34a, into positions in which barrier plate portions 31a are located away from the optical axis of the photographing optical assembly, and in which the front aperture 22b of the frame 22 remains in an open position.
Driving arms 34c come into engagement with opposed flange portions 36a of pin 36, which is movably fitted in a radial direction within front lens group support frame 22.
As shown in Figs. 31 and 32, pin 36 is engaged by a free end of an operational lever 38 which is pivoted to front securing plate 13 via pin 37, through an operational aperture 39 of the front group lens support frame 22.
Although a pivotable actuating lever is illustrated in the embodiments of Figs. 31-34, any structure which can move pin 36 inwardly in a radial direction would be satisfactory.
Pin 36 occupies a substantially radially projecting position, under the influence of the spring force of spring 34, when no external force is applied to pin 36, as is illustrated in Fig. 31. In this position, the barrier plate portions 31a are located away from the photographing optical axis or path, and aperture 22b remains in an open position.
A restricting projection or abutment 40 is provided on .~, .30 the inner wall of cam ring 14, which is adapted to bear against the outer end of the operational lever (or other analogous structure) 38 when the cam ring rotates in its fixed axial position into a predetermined position in order to press pin 36 radially inwardly; this occurs when cam ring 14 (pin 17)rotates within the opening and closing section 20a of zooming cam groove ~0.
' ~ .
133~02 With such an arrangement of the barrier mechanism, when projection 40 is not in engagement with operational lever 38, barrier plates 31a of barriers 31 open photographic opening 22b. Specifically, cam ring 14 causes rollers or pins 17 to engage any groove section other than opening and closing section 20a of zooming cam groove 20, with barriers 31 thus being opened.
To the contrary, when zooming motor 5 is driven by a lock switch (not shown in the drawings) to rotate cam ring 14, so that roller 17 will move into and engage opening and closing section 20a of zooming cam groove 20 from lens collapsing or retracting groove section 20b, projection 40 will push opening and closing pin 36, via operational lever 38, in the radial direction, and barriers 31 will rotate through their engagement with spring drive arms 34c and operational arms 34a to move the barrier plate portions 31a into the optical path of the lens system. As a result, the photographic opening 22b will be closed so as to protect front lens element group Ll. Namely, front lens groups support frame 22 closes barrie~s 31 after the frame has been collap-sed from the rearmost position from which a picture can be taken.
When a picture is to be taken, zooming motor 5 is reversed so as to rotate cam ring 14, so that the zooming cam groove 20 will ~e rotated from a position in which opening and closing section 20a is engaged by roIler(s) 17 towards a position in which lens collapsible section 20b is so engaged. ~his causes barriers 31 to open and the front lens group Ll is moved into a position in which a picture 30 can be taken. ``
Figs. 33 and 34 illustrate a second embodiment of a mechanism used in a lens shutter type of camera in accordance with the present invention. As shown in Figs. 33 and 34, this barrier mechanism 30 is basicall~ identical to the embodiment illustrated in Figs. 31 and 32.
Specifically, barrier mechanism 30 in Figs. 33 and 34 also , .
~ , t~3~2 P5713S01 _ 47 include a pair of barriers ~1, 31 which are positioned in a substantially symmetrical fashion with respect to the photographic opening 22b of front lens group support frame 22. Barriers 31, 31 are pivoted to frame 22 via pins 32 in 5 order to open and close photographic opening 22b. Kowever, details of construction of the barrier mechanism in this embodiment are different from those in the first embodiment discussed above.
Barriers 31, 31 which are illustrated in Figs. 33 and 10 34 are sylT~metrically disposed with respect to each other and include barrier plate portions 31a which can be projected onto the photography optical axis, and driving arms 3lb which lie or are disposed on opposite sides of the barrier plate portions 3la; and the barriers are pivotably attached 15 to the frame by pins 32.
Driving arms 31b include operational pins 133 which are engaged to, and which are adapted to abut or contact, a single wi.re spring 134 having elastic leg poxtions 134a. A
free end of each of the elastic leg portions 134a is adapted 20 to contact a respective pin 1:33 in order that barrier plate portions 31a will be continuously biased into an open position in which the photographic aperture 22b is opened and the barriers located away from the optical axis and the aperture. Thus, when no external force is applied to 25 barriers, they constantly maintain the photographing aperture in an open condition.
Wire spring 134 is made from metal and has a central, U-shaped portion 134b which bears against a support pin 135 provided on front lens group support frame 22. Wire spring 30 134 has a constant spring force which force will not vary in accordance with changes in temperature, humidity or other ~;~ environmental parameters. Accordingly, it is therefore possible to bias barriers 31 in a direction i.n which a photographing aperture is maintained in an open position by 35 a substantially constant spring force.
Operational pins 133 are engaged by respective driving ~' n ~l33~402 free ends 136a of a pair of right and left driving arms 136, which are spaced from each other and which are adapted to open barriers 31, by overcoming the biasing force exerted by wire spring 134. The free ends 136a of each of the driving arms 136 bears against a respective inner side of a respective operational pin 133, which is located away from the outer side of each pin against which one elastic leg portion 134a bears. Driving arms 136 are pivoted to lens support frame 22 via pins 137. Drivin~ arms include operational arm portions 136b located on opposite sides of the driving arms from free ends 136a, with a pin 137 provided between them to pivot the arm to frame 22, such that operational arm portions 136b will engage flange portions 138a of pin 138, which is radially movably fitted within an opening 39 in frame 22. Pin 138 includes a head (unreferenced) which is adapted to bear against the free end of operational lever 141; the lever is pivoted to front securing plate 13 by pin 140, and the head can extend, when depressed, through an opening 39 of frame 22. ~he opening and closing pin 138 is normally maintained in a position in whic~ it projects outwardly from the inner periphery of frame 22, and is radially movable by lever 141 into a position in which the head of pin 13B is forced inwardly through opening 39, overcoming the influence of wire spring 134. Thus when an external force is applied to pin 138, it moves radially inwardly against the force of spring 134, as seen in Fig. 34, As in the first embodiment, the cam ring 14 can be provided, along its inner wall, with a narrowing projection 40 attached to its interior peripheral surface which is adapted to push the operational lever 141 inwardly so that it will engage operational arm portions 136b (via pin flanges 138a~ when cam ring 14 rotates so that roller 17 is positioned within opening and closing section 20a of zooming ~` 35 cam groove 20. Other suitable actuating structure could also be used.
133~2 With such an arrange~ent of the barrier mechanism, barriers 31 serve to open the photographing aperture when the restriction projection 40 does not engage operational lever 141. Specifically, barriers 31 open when roller 17 is located within any of the sections of the zooming cam groove other than opening and closing groove section 20a. To the contrary, when roller 17 is moved to engage the opening and closing section 20a, after it has been positioned within lens collapsible section 20b of zooming cam groove 20 (via rotation of actuating cam ring 14 effected by zooming motor 5), projection 40 will push the opening and closing pin 138 -~
in a radially inward direction, via operational lever 141, in order to rotate barriers 31, via driving arms 136 and operational pins 133, so that barrier plate portions 31a will be brought into the optical path of the lens system.
In this condition, the photographic opening will be closed so as to protect the front lens element group Ll. Namely, after front lens group support frame 22 is collapsed from the most extreme rearward position i.e., the extreme wide angle position, in which a picture can be taken, the photographic aperture will then be closed by barriers 31.
When a picture is taken, zooming motor 5 will be reversed to rotate cam ring 14 from a position in which opening and closing section 20a is engaged by roller 17 to a position in which lens collapsible section 20b is so engaged, in order to open barriers 31, so that the front ;~
lens element group Ll will move into a position in which a ;~ picturè can be taken. ` `
F. Liaht IntercePtion AssemblY and Mechanism The light interception mechanisms are best illustrated -~-in Figs. 6 and 35-38 of the present application.
In a lens shutter type of camera as described herein, ~ the front and rear lens element groups can be independently i ~- moved along the photographing optica axis direction in -~35 order to effect a lens zooming operation. Since a gap ~exists between the front lens group frame 16 and the rear :,: :
''~ 1330~Q2 i.,,f"
lens group frame 18, and since cam ring 14, which includes through cam grooves 20 and 21 ~or actuating movement of lens frames 16 and 1~, is located about the outer peripheries of the lens frames, the possibility exists that undesirable light rays would otherwise penetrate into the photographic optical system of the camera through the gap between the front and rear lens grcup frames and through the cam grooves 20 and 21. Further, since front lens group frame 22 moves through opening 201 of front cover 200 (see Fig. 6), rays of light can also enter the camera via opening 201. The front cover 200 covers the front face of lens barrel block 1 and supports lenses I.3 and L6 of the finder as well as strobe block 2. Opening 201 is formed along and defined by an inner flange 202 of front cover 200, so that the movable decorative frame 22, i.e., which includes the front group lens frame 16, will move through opening 201 when the camera is in its zooming operation. An annular space 203 having a relatively small width W is provided between inner flange 202 and front stationary plate 13. The front stationary plate is substantially annular in configuration.
In order to prevent rays of light from penetrating into the camera, as noted above, a light intercepting mechanism has ~een provided. Specifically, a light intercepting assembly 210 which comprises a plurality of sections is provided about the outer periphery of cam ring 14 and is adapted to cover through or continuous cam grooves 20 and 21 in order to intercept rays of light and prevent them from entering the interior of lens barrel block 1. In the embodiment illustrated in Fig. 35, intercepting assembly 210 comprises a gear ring 15, a flexible code plate 90 which is adjacent to gear member lS along one side of the gear mem~er, and a light intercepting tape 211 which extends on the opposite side of the gear member 15. In other words, the annular gear member is located between the flexible code plate 90 which is wrapped about lens barrel blocX 1 ove- cam grooves 20 and 21, and the light tape 211, which is also - .
;-~ il3~132 .
~5713S01 - 51 flexible and which is wrapped about the lens barrel block so that it covers cam grooves 20 and 21.
Code plate go is provided to detect the angular position of cam ring 14 in order to automatically detect a change in the focal length of the zoom lens, a change of the F number which will vary in accordance with the changing focal length o~ the zoom lens, the extreme wide angle position of the zoom lens, the extreme telephoto position sf the zoom lens, the collapsed position of the zoom lens, the extreme macro position of the zoom lens, e.g., in order to effect a variety of controls which are disclosed in detail hereinafter with respect to the mechanism for detecting the position of the zoom lens and for deciphering information relating to the position of the zoom lens.
15Code plate 90 is formed from a ~lexible material having a light intercepting property. Intercepting tape 211 comprises a flexible material also having such a property, e.g., a dull-finish black paper. The code plate and the intercepting (paper) tape are applied to the cylindrical outer surface of cam ring 14, along opposite sides of gear member 15, in order to cover the major portions of zooming cam grooves 20 and 21. Gear 15 is preferably superimposed or overlapped over the side edges of the code plate and the intercepting tape in order to ensure the interception of rays of light, as illustrated in Fig. 6.
An annular light intercepting member 220 which forms an additional portion of the light intercepting assembly is provided in annuiar space 203, which is defined by the space between front stationary plate 13, which rotatably supports ` ~ 30the front portion of cam ring 14, and front cover 200, as best seen in Fig. 6.
Annular light intercepting member 220 which is positioned within annular space 203 comprises an elastic annular body 221, e.g., rubber, and an annular reinforcing 35plate 222, so that the light intercepting member 220 will be have the overall configuration of a substantially flat ~ .
.: ' , 1~0~02 annular ring, as best illustrated in Figs. 36 and 37. The thickness w of light intercepting member 220 is slightly less than the width W of annular space 203, so that the light intercepting member 220 can move over a small distance within space 203, along the direction of the photographing optical axis. -Elastic body 221 of light intercepting member 220 is provided, along its inner periphery, with a light intercepting lip 223 having a small width which slidably contacts the outer periphery of decorative frame 220.
Reinforcing plate 222 can be secured to elastic body 221, e.g., by partially imbedding the elastic body 221 into connecting recesses, holes or apertures 224 formed in ~ -reinforcing plate 222, which plate is made, e.g., of metal 15 or synthetic resin. The inner lip 223 is extremely flexible `
and is capable of moving in either direction axially of a lens barrier block about which it is positioned. The lip can thus pIay a minor role in reducing rebound of the ;
barrier block after it ceases movement in a first axial 20 direction. -~ ig. 38 illustrates a second embodiment of the annular ring illustrated in ~igs. 36 and 37, in which two spaced light intercepting lips 223 trather than merely one) are formed on the inner periphery of annular light intercepting member 220 in order to increase the light interception effect of the apparatus. These lips are spaced from each other in a parallel fashion and form a generally annular U-shaped, ~inwardly directed annular flange for the light intercepting member. Elastic body 221 is used to cover the outer periphery of reinforcing plate 222 in such structure.
Alternately, it would be possible to replace annular light intercepting member 220 with a conventional 0-ring structure, which would be the simplest manner of intercepting light and preventing it from reaching undesirsd areas within the camera.
With such a light intercepting mechanism, undesirable .
. 133~2 light rays will not enter the camera lens system through the circumference of the front lens group frame 16 and/or the rear lens group frame 18, nor through the front annular opening between the lens barrel and camera cover.
G. FPC Board Guide and Anti-Reflection Mechanism The FPC board guide and its associated anti-reflection mechanism of the are best illustrated in Figs. 39-43.
In a lens shutter type of camera as in the present invention, it is necessary to provide operational signals to shutter block 23 on lens barrel block 1 from the body of the camera. Shutter block 23 is supported by support frame 22 of front lens element group Ll, and accordingly moves together with front lens element group Ll along the direction of the optical axis. In order to send operational signals from the camera body to the shutter block 23 which moves in such an optical axis direction, in response to outputs of the distance measuring device, i.e., the range finder, and, e.g., the exposure control device on the camera body, a flexible printed circuit board (hereinafter referred to as an FPC board) is desirably used. The mechanism for guiding movement of the FPC board and the anti-reflection assembly which are used in conjunction with such bc~ard are described hereinbelow in detail with more specific reference to Figs. 39-43.
FPC board 160 (see Figs. 39 and 40~ provides operational signals to shutter block 23 from one side of the camera body. This board is made from a flexible synthetic resin sheet having f a predetermined printed circuit pattern thereon; in general, such FPC boards are well known.
As illustrated in Fig. 39, FPC board 160 has a connecting pattern 161 at a front end of the board to which shutter bloc}c 23 can be electrically connected, and a rear connecting pattern 162 to which a CPU (a central processing ~; unit which is not illustrated in the drawings) which is -provided in the camera body can be electrically connected.
FPC board guide plate 163, which guides FPC board 160, is .- `' ~' , 7 ~ 3 ~
P5713Sol - 54 secured to the camera body at a base or rear portion thereof, and extends into a space between cam ring 14 and decorative frame 22, forwardly of lens barrel block 1.
Securing clips 166 are provided for attaching the FPC board 163 to the guide plate, and clamping members 167 (see Fig.
41) are provided for attaching the FPC board to the front portion of a camera body frame, e.g., which is die cast, or tG the rear portion of a lens barrel frame(base 6).
A bent guide 165 is provided on the front end of FPC
board 163; this bent guide comprises a pair of front and rear guide pins 168 and 169. These guide pins are preferably stationary (although it is conceivable that rollers could be used instead) and are adapted to maintain the curvature of the FPC board 163 along an immovable bent portion 160a of the board, at which point the board extends ~orwardly from the camera body and is bent in opposite directions so as to extend towards the camera body. FPC
board 160, which is bent around guide pin 168, extends rearwardly into the gap between guide.pin 169 and FPC board guide plate 163, and is again freely bent forwardly by or at a movable bent portion 160b.
It should be appreciated that the relative positional relationship between guide pins 168 and 169, and FPC board 160, is constant, irrespective of the movement of shutter block 23 forwardly and rearwardly in an axial direction.
Accordingly, guide pins 168 and 169 are preferably immovable pins which are not rotatable. Alternately, it is possible to replace these pins with guide rods or shafts over which the FPC board will be bent in opposite directions.
As shutter block 23 moves forwardly and rearwardly, the movable bent portion 160b of the FPC board also moves forwardly and rearwardly. Although the extension of the FPC
board 160 extends rearwardly from the board guide plate 163, as shown in Figs. 39 and 40, actually the rear extension of FPC board 160 can be bent forwardly along, and by, a bent guide 170 of guide plate 163 in order to move the board ; ! ` "
~33~1~a2 P5713S01 _ 55 towards the front part of the camera body.
The inner surface of FPC board 160 faces the gap between the front lens group frame 16 (as well as decorative frame 22) and rear group lens frame 18, and there is therefore a possibility that rays of light which are incident ~pon the lens system will be reflected b~ ~PC board 160, resulting in undesirable internal reflection. In order to prevent such internal reflection, an anti-reflection material or apparatus can be (and should be) provided on FPC
board 160.
Several alternate solutions can be used to provide anti-reflection means on the FPC board 160. As one solution, FPC board 160 can be formed from a dull-fini-sh, blac~ synthetic resin material. Alternately, the FPC board 160 can be provided along its inner surface, i.e., on its surface which is adjacent to the optical axis o~ the camera, with an anti-reflection sheet 171, as illustrated in Fig.
43. Such a sheet can comprise, e.g., a dull-finish black paper or the like, and is adapted to be placed on the FPC
board 160. Preferably, the anti-reflection sheet 171 is simply loosely superimposed on the FPC board without being adhered to the board in order to provide flexibility against deformation due to expansion and shrinkage of the material.
Sheet 171 lies on the FPC board in the area between bent portions 160a and 160b of FPC board 160. A third solution is to coat at least the inner surface of FPC board 160 with an anti-reflective laver.~
with the guide mechanism of the FPC board and with the anti-reflection mechanism which are noted above, when the zooming motor 5 is driven to rotate in order to rotate cam ring 14, front lens group frame 16 and rear lens group frame 18 will be moved in directions along the optical axis in accordance with the cam grooves 20 and 21 on cam ring 14 in order to effect a zooming operation, and can be moved into a position in which the camera is in its macro setting or mode. Movement of the front lens group frame 16 causes . ,.
~ ~r ~
133~D2 P5713S01 ~ 56 _ shutter block 23 to move in the same direction, so that FPC
board 160 will be extended in accordance with movement of the shutter block 23. Extension of the board is made possible by displacement of movable bent board portion 160b.
5 Specifically, FPC board 160 is integrally connected to the CPU in the body of the camera at rear end connecting pattern or portion 162 (see Fig. 39) and the intermediate portion of the FPC board is guided by FPC guide plate 163. The immovable bent portion 160a of the FPC board 160 is 10 immovably guided by guide pins 168 and 169; and, accordingly, when the front end connecting pattern 161 of FPC board 160 moves in accordance with or in response to movement of shutter block 23, only the movable bent board portion 160b will be displaced forwardly and rearwardly in 15 order to absorb the movement of shutter block 23, as illustrated in Figs. 40 and 42. In this fashion, FPC board 160 can be surely guided within the annular space 164 located between cam ring 14 and decorative frame 22 (Fig 41).
Since the FPC board 160 has an anti-reflection structure as disclosed above, internal reflections which would otherwise cause an undesirable phenomena, e.g., a . -flare or a ghost, will not ~ccur.
H. Detection Mechanism for Detectinq Information Relatinq to -~
25 the Position of the Zoom Lens As noted previously, in a lens shutter camera formed in accordance with the present invention, the photographic optical system ``is moved along the optical axis ~by the rotation of cam ring 14, so that the focal length of the 30 photographic optical system will vary, and so that the ~ optical system will move from one extreme angular position ;~ of the cam ring into the macro setting position, and from the other extreme angular position of the cam ring into a lens (totally) collapsed position. In sush a lens shutter 35 type of camera, which includes a zoom lens, it is necessary, e.g., to detect the focal length of the photographic optical ~33~2 system, the macro setting position, and the two extreme positions of the cam ring in order to indicate the focal length, to control the exposure which varies in accordance with the F number, and to control the direction of rotation of the motor which drives the cam ring.
In the present invention, the above information, i.e., relating to the focal length and the two extreme positions of th zoom lens, can easily be detected by code signals on the single flexible code plate 90 which is provided on cam ring 14. Specifically, code plate 90, as illustrated in Fig. 44, is provided on cam ring 14 (which is shown in Fig.
1) and is brought into sliding contact with a brush 92 (Fig. -44) which is secured at its base end to a stationary frame 91 positioned on the outside of cam ring 14. This is well 15 illustrated in Fig. 1. ~ -Fig. 44 illustrates the developed code plate 90, in a flattened condition, in which the upper half of the drawing illustrates the cam profiles of zooming cam groove 20 and 21 of cam ring 14, .and cam grooves 55, 56 and 57 of cam plate 53, respectively. Brush 92 includes a common terminal C and independent (bristles) terminals T0, Tl, T2, and T3. When each of terminals T0-T3 is electrically connected to the conductive lands 93 of code plate 90, a signal "0" is issued, and when each of the terminals T0-T3 are not electrically connected to conductive lands 93, a signal "1"
is issued. The angular position of cam ring 14 can be detected by the combination of signals "0" and "1". A
plurality of dummy terminals 94 are formed in conductive lands 93. The purpose of the dummy terminals, which are formed from the same material as conductive lands 93, is that the flexible code plate bent about the cam ring, and in order to improve the physical strength of the plate and ~;~ still provide an area without electrical contact the dummy terminals were so positioned to increase flexibility while preserving strength. Additionally, these dummy terminals provide (non-conductive) lands upon which the terminals T0-, _ ' ! ~
~330~a2 P5713SOl - 58 T3 of the brush can ride as the cam ring is rotated.
The four bit information received from termi~als TO-T3 are provided as zoom code data ZPo, ZPl, ZP2, and ZP3, respectlvely, of a zoom code encoder, as is clearly illustrated in Fig. 45. This figure comprises a table of combinations of signals "o" and "l", in which the angular position, i.e., PoS, of cam ring 14 is divided into 13 steps between "0" and "9", and "A", "~", and "C", respectively, which are hexadecimal numbers. The number "0" designates a locked position, and the "C" position designates a position in which the camera is in its macro mode. Between the loc~ed position and the macro position, there are nine focal length positions fo-f7'. The locked position and the macro position correspond to the two extreme angular positions of the cam ring 14. Zooming motor 5 is controlled so that the cam ring 14 will not rotate beyond the two extreme positions. These angular or rotational positions are shown on the code plate in Fig. 44.
Rotation of cam ring 14 is controlled by the mode changing switch 101 and the zoom switch 102, which are illustrated in Figs. 47-50, in accordance with positional information of cam ring 14 as determined by code plate 90.
The arrangement of mode changing switch 101 and zoom switch 102 on the camera body is illustrated in Figs. 46-48.
A release button 99 is provided on the upper surface of the camera which can be pushed by one step to turn a photometry switch into an ON position, and which can be pushed by two steps to turn a releasé switch into an ON position (neither -~
of these two switches are shown in the drawings, however).
Mode changing switch 101 is a transfer switch which can occupy 3 positions, i.e., a lock position (LOC~), a zooming position (i.e., ZOOM), and a macro position, i.e. (MACRO). -~
As illustrated in Figs. 49-50, when macro button 101a is not depressed, switch lever 101b can move between the LOCK and ~-ZOOM positions. When macro button 101a is depressed, however, and when switch lever 101b slides onto the upper ~333l~L02 surface of macro button lOla, the macro mode of the camera will be set. Figs. 49 and 50 are cross-sections of the macro and ~oom-lock switches, respectively. When in the LOCK position, neither the releasing operation nor the zooming operation of the 7oom lens can be effected. In the ZOOM position, however, the release operation and the zooming operation can be carried out. In the MACRo position, the releasing operation can be performed but the zooming operation cannot be effected.
10Fig. 51 illustrates an alternate arrangement of the zoom switch, in which the zoom lens is moved towards a telephoto position when a telephoto button T is pushed and towards a wide angle position when a wide angle button W is pushed.
15Zoom switch 102 occupies a neutral position, i.e., it is placed into an OFF position, when no external force is applied to the switch; and it can be manually moved into a wide angle position, i.e., a WIDE position, and into a . telephoto position, i.e., a TELE position, which positions are located on opposite sides of the neutral "OFF" position.
Zooming motor 5 can be rotated in both forward and reverse directions by switching the position of zoom switch 102 . between the WIDE and TELE positions.
Mode changing switch 101 and zoom switch 102 actuate the camera of the present invention as detailed hareinafter.
In actual use, positional information relating to the position of cam ring 14 which is indicated by code plate 90 will be used.
1. For the LOCK position of the mode changing switch 101, zooming motor 5 is reversed to rotate cam ring 14.
When the angular position POS of cam ring 14 becomes "O"
(see Figs. 44 and 45) as detected by code plate 90 and brush 92, zooming motor 5 will stop rotating.
2. For the MACRO position of the mode changing switch ;~ 35 101, zooming motor 5 rotates in the forward direction and ~ stops rotating when POS reaches the "C" position.
1 3 ~ 2 3. For the ZOOM position of the mode changing switch 101, zooming motor 5 reverses when zoom switch 102 is in the WIDE position, and rotates in the forward directlon when the zooming switch is in the TELE position. Zooming motor 5 will stop rotating when POS reaches the "A" position, when the zoom switch is in the TELE position. When the zoom switch is in its WIDE position, zooming motor 5 will continue reversing for a predetermined short span of time after PoS reaches the "1" position. Af'ter this time, zooming motor 5 will begin rotating in a forward direction and will stop rotating when PoS becomes 2.
When zoom switch 102 is turned to the OFF, i.e., neutral, position, during rotation of zooming motor 5, the zooming motor will immediately stop rotating when the zoom switch is in the TELE position, and will stop after it rotates in the forward direction for a predetermined short period of time when it is in the WIDE position, respectively.
Details of several of the positions will now be described. ' POS 1: Since the code signals change at the LOCK
position and at the extreme WIDE position, these extreme positions are detected. More precisely speak'ing, the LOCK
position is not "POS 0", but is instead a point which is located between POS 0 and POS 1. However, when the camera is in the LOCK position, the brush is in POS 0, in a location very close to POS 1. Similarly, the WIDE extreme position is apoint'between POS 1 and POS~2. However, when the camera is in the extreme WIDE position, (which is not a wide zone), brush 92 is in POS 2, which is very close to POS
1. Accordingly, POS 1 denotes a range in which the cam ring 14 moves from the extreme WIDE position to the LOCK
position, and vice versa.
:~POS f7 ': This zone is provided for absorbing the ~35 backlash of cam ring 14 ~ie., backlash from movement of the ;~lçns system). Specifically, as illustrated in Fig. 45, f y '~ '`' l33a~a2- -during rotation of the cam ring from PoS o towards POS c, the cam ring will stop immediately when a stop signal is given, i.e., when the zoom switch is turned to an off position. To the contrary, rotation of the cam ring from PoS C towards POS o causes the cam ring 14 to reverse slightly after it overruns its desired position by a predetermined displacement, and then stops the cam ring at a first changing POS point. POS f7' is the extreme TELE
position, and, accordingly, when cam ring is in its extreme 10 TELE position (with the TELE zone being a zone in which the cam ring operates at the TELE exposure), the brush will be located at position POS A, which is very close to POS 9.
The focal length information or the F number information are fed to the shutter by the code plate and the brush.
Accordingly, the same focal length information is fed at the TELE zone and the TELE extreme positions. This is the reason that POS 9 is represented by f7 and POS A is represented by f7' in order to distinguish it from f7. The zone f7' is quite small, and accordingly the zone f7' can essentially be considered identical to the extreme TELE
position.
POS B: In a fashion similar to POS 1, this zone is provided to distinguish the extreme MACRO and TELE
positions. Unlike POS 1, in which the WIDE extreme position is a changing point between P~S 1 and the- WIDE extreme position, and PoS s is an extreme TEL~ position representing changing points between POS 9 and POS A, respectively.
POS 2 - PoS A: These are intermediate focal length positions which comprise a plurality, e.g., 9 in the illustrated embod`iment, steps.
The CPU then checks the code information and the setting positions for the various switches when they are ~turned into their ON positions. If the mode changing switch `-~ i5 in a zoom position, no zooming will be necessary when the -~ 35 cam ring i~ in any position between and including POS 2 and POS A. If, however, the mode changing switch is 'n a ,~: ' -;
, ;: ~33~2 P5713S01 ~ 62 position other than the zoom position, i.e., in either the LOCK position, an intermediate position between LOCK and WIDE, an intermediate position between TELE and MACRO, or the MACRO position, zooming operation of the lens will be immediately effected. This is also true when the switch is brought into the zoom position during rotation of the zooming motor in the forward direction and when the switch is brought into the zoom position during reverse rotation of the zoomin~ motor. Specifically, when in the zoom position, whether the zoom code is within the range between and including POS 2 to PoS A (within which range zooming is -~
effected) will be checked by the CPU. If the zoom code is out of the range, no picture can be taken, and, accordingly, the cam ring will be moved into the zooming position. In other words, POS 1 and POS B are areas in which the cam ring is prohibited from stopping and in which a picture cannot be taken.
o~ course, it is clear that the present invention is not limited to the embodiments described above, nor those illustrated in the drawings, and the invention can be modified without departing from the spirit and scope of the claimed invention.
. ~
(1) 0-3 <dP<0.5;
(2) fl+ <1.8; and (3) 0.45< f3/LD <0.7; wherein:
LD = the total length of the finder;
dP = the distance between the face of lens L3 which is most closely adjacent to prism Pl and the face of lens LS
~ .. . .
~3~ a2 P5713S01 _ 39 which is most closely adjacent to prism Pl;
fl+ = the focal length of the positive lens of the first lens group, and f3 = the focal length of the third lens group.
These criteria are useful and helpful to enable prism Pl to be retractably inserted between the movable lens L3 of the first lens group and the negative lens L5 of the first lens group and ~o minimize the effective diameter of the prism when it is brought into alignment with the optical axis.
The first condition, i.e., 0.3 < dP < 0.5 is based upon the fact that if the value of dP exceeds the noted upper limit, the effective diameter of the l~ns L3 will become large, making it difficult to provide a compact camera as doe~ the present invention; to the contrary, if the value-of dP was <0.3, it would become extremely difficult to smoothly and easily rotate prism Pl so that it would come into alignment with, and be capable of retracting away from, the optical axis in a position between lenses L3 and L5.
Conditions 2 and 3, in which fl+ < 1.8, and 0.45 <
f3/LD <0.7, are provided to minimize the effective diameter of prism Pl. The second criteria noted above is substantially e~uivalent to setting or establishing the focal-length FR of the lens system which is positioned rearwardly of prism Pl when the prism is in alignment with the finder optical axis. Namely, if fl+ exceeds its noted upper limit of 1.8, the effective diameter of the prism will become large, thereby resulting in difficulty in realizing a compact prism and finder.
Condition three is basically equivalent to a ~ requirement for the third lens group located rearwardly of ;~ the prism. Namely, if f3/LD is less than the lower limit of 0.45, the tolerance of the system will become ~uite small.
To the contrary, if the value of f3/LD exceeds the upper ~; 35 limit of 0.7, the effective diameter of the prism will ~ increase.
:: :
:; ~
? ~ ~..'1 S~ 3 3 ~ f~
The values of dP, fl+, and f3/LD in the first and second embodiments above will now be listed; all of these values are set to satisfy conditions 1, 2 and 3 noted above.
First Embodiment Second Embodiment dP 0.45 0.36 fl+ 1.76 1.42 f3/LD 0.56 0~49 D. Drive Mechanism for the Finder and Strobe Devices The driving mechanism which serves to actuate finder 10 optical assembly 8 and strobe assembly 9 is best illustrated in Figs. 21-30.
A mother plate 60 is attached to a finder block 54 which is mounted to base plate 6 via horizontal support plate extension 6b. The mother plate is provided with guide 15 pins 62 integrally attached to the mother plate and which are adapted to fit within a substantially linear guide groove 61 of cam plate 53. Sliding motion of cam plate 53 is in the lateral direction, with respect to the optical axis of the camera, and is restricted by the engagement 20 between guide grooves 61 and guide pins 62; and a guide projection o,r flange 60a (shown in both Figs. 21 and 22) is formed integrally with mother plate 60 and serves to prevent cam plate 53 from floating or moving away from the front ~ surfac:e of the mother plate, particularly at the front end '~ 25 of cam plate 53 where the flange engages the cam plate.
Finder mother plate 60 includes a variable power lens guide groove 63, a deflection prism guide groove 64, and a ~; strobe as'sembly 'guide 'groove 65. ~:achl of these guide grooves extends parallel to the photographic ~ptical axis of 30 the camera. A guide projection 66a of variable finder lens frame 66, which carries the variable finder power lens group L5, is fitted within variable power lens guide groove 63.
Guide projection 67a of deflection prism actuating plate 67 ,~ is slidably positioned or fitted within deflection prism 35 guide groove 64; and guide projection 68a of strobe assembly case 68, which casing has a concave reflector 59 attached ~ 3 3 ~ !~ o ~
P5713Sol - 41 thereto, is fitted or positioned within strobe guide groove 65.
Variable power lens frame 66, deflection prism actuating plate 67, and strobe assembly case 68, together move in a direction which is parallel with respect to the optical axis, along the respective guide grooves. Guide projections 66a, 67a, and 68a are provided with driven pins 69, 70 and 71, which fit within the varia~le power cam groove 55, the parallax compensating cam groove 56, and the strobe cam groove 57, respectively. Accordingly, when cam plate 53 moves laterally, variable power lens frame 66, reflection prism actuating plates 67, and strobe case 68 move along the respective camming grooves 55, 56 and 57.
The sections of the variable power cam groove 55, parallax compensating cam groove 56, and strobe cam groove 57 correspond to sections of zooming cam grooves 20 and 21 of cam ring 14 which have been illustrated in Fig. 7 and described with respect thereto. Specifically, the variable power cam groove 55 includes an extreme wide angle fixing section 55a, a variable power section 55b, and an extreme telephoto fixing section 55c, with the angles 0 1~ 0 2 and ~ 3, respectively, of these three sections corresponding to the similar angles in the cam ring Fig. 7. The parallax compensating cam groove 56 includes a non-projecting section 56a, a projecting movement section 56b, i.e., a forward feed section used for the macro mode, and a projected position fixing section 56c, i.e., an extreme macro fixing section.
Strobe cam groové 57 includes an extreme wide angle !flxing section 57a, a variable power section 57b, an extreme telephoto fixing section 57c, a macro feeding section 57d, and an extreme macro fixing section 57e. The relationship between cam grooves 55, 56 and 57, and zooming cam grooves 20 and 21, is best illustrated in the schematic or pla~ view illustrated in Fig. 44.
The variable power lens frame 66 which supports the variable power lens group L5 is movably supported along -~
~ .
~3~a~a2 guide face 54a of finder block 54 so that frame 66 will hang therefrom, as best illustrated in Fig. 25. The frame can be formed, e.g., from a resin which can slide with respect to the finder block in a substantially frictionless fashion.
When variable power lens frame 66 moves along variable power cam groove 55, magnification of the finder optical system, including lens group L3, eye piece group L4, and variable power lens group L5, will vary, so that the photographic range over which lens barrel block 1 moves will be substantially coincident with the field of view of the finder.
The deflection prism actuating plate 67 is illustrated in Figs. 26-Z8, and is hereinafter described in greater detail.
Deflection prism Pl, which is formed of synthetic resin, is rotatably supported by finder block 54 via two lower opposed prism support pins 74 of the prism. These supporting pins include torsion springs 75 which surround them, with one end of each spring bearing against a respective abutment 76 which abutments are provided along the side faces of defIection prism P1, so that the deflection prism will be continuously biased into a position in which the prism Pl moves into alignment with the optical axis of finder lenses L3-L5. Abutment 76 are located in arc-shaped grooves 79 formed in finder block 54, as best illustrated in Figs. 26-28. The deflection prism actuating plate 67 is held between finder block 54 and a guide plate 80 (see Fig. 25) connected to finder block 54 so that a guide pin 81 which is positioned on the side face of finder block 54 will fit within linear guide groove 82 of guide plate 80.
Position restricting abutments 76 on the prism can be engaged by a stop surface 77 and a guiding surface 78 0 r deflection prism actuating plate 67; further, the prism abutments 76 can come into contact with an end surface of the groove 79 in plate 67 (see Fig. 27). Deflection prism ~,.... ,.;... . ............ ... .........
~33~2 P5713Sol - 43 actuating plate 67 serves to retract the deflection prism from the optical path of lenses L3-L5, against the bias of springs 75, when pin 70 is located in the non-projection section 56a of parallax compensating cam groove 56, insofar as the rotation preventing face 77 of the plate will move into engagement with abutment 76 (see Fig. 26). When pin 70 moves into the projecting movement section 56b, guide surface 78 will move into a butting contact with abutment 76, so that deflection prism Pl will rotate into a position lo in which lt is in alignment with the finder system optical axis with the help of torsion spring 75. During such movement, abutments 76 move on and along face 78, and deflection prism Pl will gradually move into the optical path, as illustrated in Figs. 27 and 28, so that the optical path of th~ finder will be deflected downwardly by prism Pl, as illustrated by the arrow in Fig. 28. As a result of this movement, a subject which is otherwise located below the finder optical axis will come into the camera field of view, and parallax in the macro mode of the camera will be decreased. It is even further decreased, as noted above, when a double wedge prism (Fig. 53A) is used to deflect the finder optical axis downwardly and (rightwardly) towards the optical axis of the photographing optical system.
A guide block 85 is provided along the side face of strobe case 68 and is fitted within a linear guide groove 84 which is parallel to the optical axis of the camera which is formed in guide plate 80, as illustrated in Fig. 30.
~ Further, height adjusting pins 86 (see Figs. 23 and 29) are ;~ provided on the upper and lower faces of strobe case 68 and are adapted to prevent the strobe case from falling ~ downwardly. The strobe case 68 moves along strobe cam - g-oove 57 when cam plate 53 moves in the lateral direction.
Variable power section 57b of strobe cam groove 57 is adapted to move xenon lamp 58 rearwardly, away from Fresnel lens L6. Rearward movement of the xenon lamp 58 causes the illumination angle of light emitted from Fresnel lens L6 to ~ ' ~-~!~ (. '`"
~:3~
P5713Sol _ 44 decrease so as to substantially increase the guide number in accordance with an increase in the focal length. To the contrary, in macro feeding section s7d, the illumination anyle is increased, and the guide number is therefore substantially decreased in the macro mode.
E. Barrier, i.e. Lens CaP Mechanism The barrier lens cap mechanism is best illustrated in Figs. 6, 8 and 31-34.
Barrier mechanism 30 opens and closes a pair of lo barriers 31, (see Fig.8 ) which are located forwardly of the front lens element group Ll of the photographi~ (zooming~
lens system, and which are closed with the ass;stance of rotational force which is produced when cam ring 14 rotates within retracting or storing cam section 20b (see Fig. 7) ln which the lens is collapsed.
Fig. 31 and 32 illustrate a first embodiment of the barrier mechanism. In this embodiment, barrier mechanism 30 opens and closes a photographic opening 22b at the opening of frame 22 via pivoted barrier elements 31. The barrier elements are pivoted, via pins 32, in a substantially symmetrical fashion with respect to the photographic opening 22b of the front lens group support frame 22.
Barriers 31 are disposed in a symmetrically opposite position with respect to each other and include respective barrier plate portions 3la which can be moved so as to project into the path of the photographing optical axis, as well as driving arm portions 31b which are positioned on the opposite sides of the barriers from the side on which barrier plate portions 31a are located. Driving arm ; 30 portions 31b are generally attached to the inner front surface of barrier assembly 30 by pins 33. Driving arm portions 31b include pins 33 which are engaged by operational arms 34a of opening and closing springs 34, as shown in Figs. 31 and 32. In other words, pins 33 are ;~ 35 adapted to slide within, and/or be moved by, respective ~; fork-shaped end portions of the driving arms.
~33~4a2 Opening and closing springs 34 are comprised, e.g., of molded synthetic resin and include the Y-shaped spring arm 34b and driving arm portions 34c, in addition to the fork-shaped operational arms 34a which engage pins 33. Each of the springs is pivoted to the barrier mechanism 30 by a respective pin 35. Spring arms 34b bear against the inner wall of the front lens group support frame 22 in order to continuously bias barrier plate portions 3la, via operational arm 34a, into positions in which barrier plate portions 31a are located away from the optical axis of the photographing optical assembly, and in which the front aperture 22b of the frame 22 remains in an open position.
Driving arms 34c come into engagement with opposed flange portions 36a of pin 36, which is movably fitted in a radial direction within front lens group support frame 22.
As shown in Figs. 31 and 32, pin 36 is engaged by a free end of an operational lever 38 which is pivoted to front securing plate 13 via pin 37, through an operational aperture 39 of the front group lens support frame 22.
Although a pivotable actuating lever is illustrated in the embodiments of Figs. 31-34, any structure which can move pin 36 inwardly in a radial direction would be satisfactory.
Pin 36 occupies a substantially radially projecting position, under the influence of the spring force of spring 34, when no external force is applied to pin 36, as is illustrated in Fig. 31. In this position, the barrier plate portions 31a are located away from the photographing optical axis or path, and aperture 22b remains in an open position.
A restricting projection or abutment 40 is provided on .~, .30 the inner wall of cam ring 14, which is adapted to bear against the outer end of the operational lever (or other analogous structure) 38 when the cam ring rotates in its fixed axial position into a predetermined position in order to press pin 36 radially inwardly; this occurs when cam ring 14 (pin 17)rotates within the opening and closing section 20a of zooming cam groove ~0.
' ~ .
133~02 With such an arrangement of the barrier mechanism, when projection 40 is not in engagement with operational lever 38, barrier plates 31a of barriers 31 open photographic opening 22b. Specifically, cam ring 14 causes rollers or pins 17 to engage any groove section other than opening and closing section 20a of zooming cam groove 20, with barriers 31 thus being opened.
To the contrary, when zooming motor 5 is driven by a lock switch (not shown in the drawings) to rotate cam ring 14, so that roller 17 will move into and engage opening and closing section 20a of zooming cam groove 20 from lens collapsing or retracting groove section 20b, projection 40 will push opening and closing pin 36, via operational lever 38, in the radial direction, and barriers 31 will rotate through their engagement with spring drive arms 34c and operational arms 34a to move the barrier plate portions 31a into the optical path of the lens system. As a result, the photographic opening 22b will be closed so as to protect front lens element group Ll. Namely, front lens groups support frame 22 closes barrie~s 31 after the frame has been collap-sed from the rearmost position from which a picture can be taken.
When a picture is to be taken, zooming motor 5 is reversed so as to rotate cam ring 14, so that the zooming cam groove 20 will ~e rotated from a position in which opening and closing section 20a is engaged by roIler(s) 17 towards a position in which lens collapsible section 20b is so engaged. ~his causes barriers 31 to open and the front lens group Ll is moved into a position in which a picture 30 can be taken. ``
Figs. 33 and 34 illustrate a second embodiment of a mechanism used in a lens shutter type of camera in accordance with the present invention. As shown in Figs. 33 and 34, this barrier mechanism 30 is basicall~ identical to the embodiment illustrated in Figs. 31 and 32.
Specifically, barrier mechanism 30 in Figs. 33 and 34 also , .
~ , t~3~2 P5713S01 _ 47 include a pair of barriers ~1, 31 which are positioned in a substantially symmetrical fashion with respect to the photographic opening 22b of front lens group support frame 22. Barriers 31, 31 are pivoted to frame 22 via pins 32 in 5 order to open and close photographic opening 22b. Kowever, details of construction of the barrier mechanism in this embodiment are different from those in the first embodiment discussed above.
Barriers 31, 31 which are illustrated in Figs. 33 and 10 34 are sylT~metrically disposed with respect to each other and include barrier plate portions 31a which can be projected onto the photography optical axis, and driving arms 3lb which lie or are disposed on opposite sides of the barrier plate portions 3la; and the barriers are pivotably attached 15 to the frame by pins 32.
Driving arms 31b include operational pins 133 which are engaged to, and which are adapted to abut or contact, a single wi.re spring 134 having elastic leg poxtions 134a. A
free end of each of the elastic leg portions 134a is adapted 20 to contact a respective pin 1:33 in order that barrier plate portions 31a will be continuously biased into an open position in which the photographic aperture 22b is opened and the barriers located away from the optical axis and the aperture. Thus, when no external force is applied to 25 barriers, they constantly maintain the photographing aperture in an open condition.
Wire spring 134 is made from metal and has a central, U-shaped portion 134b which bears against a support pin 135 provided on front lens group support frame 22. Wire spring 30 134 has a constant spring force which force will not vary in accordance with changes in temperature, humidity or other ~;~ environmental parameters. Accordingly, it is therefore possible to bias barriers 31 in a direction i.n which a photographing aperture is maintained in an open position by 35 a substantially constant spring force.
Operational pins 133 are engaged by respective driving ~' n ~l33~402 free ends 136a of a pair of right and left driving arms 136, which are spaced from each other and which are adapted to open barriers 31, by overcoming the biasing force exerted by wire spring 134. The free ends 136a of each of the driving arms 136 bears against a respective inner side of a respective operational pin 133, which is located away from the outer side of each pin against which one elastic leg portion 134a bears. Driving arms 136 are pivoted to lens support frame 22 via pins 137. Drivin~ arms include operational arm portions 136b located on opposite sides of the driving arms from free ends 136a, with a pin 137 provided between them to pivot the arm to frame 22, such that operational arm portions 136b will engage flange portions 138a of pin 138, which is radially movably fitted within an opening 39 in frame 22. Pin 138 includes a head (unreferenced) which is adapted to bear against the free end of operational lever 141; the lever is pivoted to front securing plate 13 by pin 140, and the head can extend, when depressed, through an opening 39 of frame 22. ~he opening and closing pin 138 is normally maintained in a position in whic~ it projects outwardly from the inner periphery of frame 22, and is radially movable by lever 141 into a position in which the head of pin 13B is forced inwardly through opening 39, overcoming the influence of wire spring 134. Thus when an external force is applied to pin 138, it moves radially inwardly against the force of spring 134, as seen in Fig. 34, As in the first embodiment, the cam ring 14 can be provided, along its inner wall, with a narrowing projection 40 attached to its interior peripheral surface which is adapted to push the operational lever 141 inwardly so that it will engage operational arm portions 136b (via pin flanges 138a~ when cam ring 14 rotates so that roller 17 is positioned within opening and closing section 20a of zooming ~` 35 cam groove 20. Other suitable actuating structure could also be used.
133~2 With such an arrange~ent of the barrier mechanism, barriers 31 serve to open the photographing aperture when the restriction projection 40 does not engage operational lever 141. Specifically, barriers 31 open when roller 17 is located within any of the sections of the zooming cam groove other than opening and closing groove section 20a. To the contrary, when roller 17 is moved to engage the opening and closing section 20a, after it has been positioned within lens collapsible section 20b of zooming cam groove 20 (via rotation of actuating cam ring 14 effected by zooming motor 5), projection 40 will push the opening and closing pin 138 -~
in a radially inward direction, via operational lever 141, in order to rotate barriers 31, via driving arms 136 and operational pins 133, so that barrier plate portions 31a will be brought into the optical path of the lens system.
In this condition, the photographic opening will be closed so as to protect the front lens element group Ll. Namely, after front lens group support frame 22 is collapsed from the most extreme rearward position i.e., the extreme wide angle position, in which a picture can be taken, the photographic aperture will then be closed by barriers 31.
When a picture is taken, zooming motor 5 will be reversed to rotate cam ring 14 from a position in which opening and closing section 20a is engaged by roller 17 to a position in which lens collapsible section 20b is so engaged, in order to open barriers 31, so that the front ;~
lens element group Ll will move into a position in which a ;~ picturè can be taken. ` `
F. Liaht IntercePtion AssemblY and Mechanism The light interception mechanisms are best illustrated -~-in Figs. 6 and 35-38 of the present application.
In a lens shutter type of camera as described herein, ~ the front and rear lens element groups can be independently i ~- moved along the photographing optica axis direction in -~35 order to effect a lens zooming operation. Since a gap ~exists between the front lens group frame 16 and the rear :,: :
''~ 1330~Q2 i.,,f"
lens group frame 18, and since cam ring 14, which includes through cam grooves 20 and 21 ~or actuating movement of lens frames 16 and 1~, is located about the outer peripheries of the lens frames, the possibility exists that undesirable light rays would otherwise penetrate into the photographic optical system of the camera through the gap between the front and rear lens grcup frames and through the cam grooves 20 and 21. Further, since front lens group frame 22 moves through opening 201 of front cover 200 (see Fig. 6), rays of light can also enter the camera via opening 201. The front cover 200 covers the front face of lens barrel block 1 and supports lenses I.3 and L6 of the finder as well as strobe block 2. Opening 201 is formed along and defined by an inner flange 202 of front cover 200, so that the movable decorative frame 22, i.e., which includes the front group lens frame 16, will move through opening 201 when the camera is in its zooming operation. An annular space 203 having a relatively small width W is provided between inner flange 202 and front stationary plate 13. The front stationary plate is substantially annular in configuration.
In order to prevent rays of light from penetrating into the camera, as noted above, a light intercepting mechanism has ~een provided. Specifically, a light intercepting assembly 210 which comprises a plurality of sections is provided about the outer periphery of cam ring 14 and is adapted to cover through or continuous cam grooves 20 and 21 in order to intercept rays of light and prevent them from entering the interior of lens barrel block 1. In the embodiment illustrated in Fig. 35, intercepting assembly 210 comprises a gear ring 15, a flexible code plate 90 which is adjacent to gear member lS along one side of the gear mem~er, and a light intercepting tape 211 which extends on the opposite side of the gear member 15. In other words, the annular gear member is located between the flexible code plate 90 which is wrapped about lens barrel blocX 1 ove- cam grooves 20 and 21, and the light tape 211, which is also - .
;-~ il3~132 .
~5713S01 - 51 flexible and which is wrapped about the lens barrel block so that it covers cam grooves 20 and 21.
Code plate go is provided to detect the angular position of cam ring 14 in order to automatically detect a change in the focal length of the zoom lens, a change of the F number which will vary in accordance with the changing focal length o~ the zoom lens, the extreme wide angle position of the zoom lens, the extreme telephoto position sf the zoom lens, the collapsed position of the zoom lens, the extreme macro position of the zoom lens, e.g., in order to effect a variety of controls which are disclosed in detail hereinafter with respect to the mechanism for detecting the position of the zoom lens and for deciphering information relating to the position of the zoom lens.
15Code plate 90 is formed from a ~lexible material having a light intercepting property. Intercepting tape 211 comprises a flexible material also having such a property, e.g., a dull-finish black paper. The code plate and the intercepting (paper) tape are applied to the cylindrical outer surface of cam ring 14, along opposite sides of gear member 15, in order to cover the major portions of zooming cam grooves 20 and 21. Gear 15 is preferably superimposed or overlapped over the side edges of the code plate and the intercepting tape in order to ensure the interception of rays of light, as illustrated in Fig. 6.
An annular light intercepting member 220 which forms an additional portion of the light intercepting assembly is provided in annuiar space 203, which is defined by the space between front stationary plate 13, which rotatably supports ` ~ 30the front portion of cam ring 14, and front cover 200, as best seen in Fig. 6.
Annular light intercepting member 220 which is positioned within annular space 203 comprises an elastic annular body 221, e.g., rubber, and an annular reinforcing 35plate 222, so that the light intercepting member 220 will be have the overall configuration of a substantially flat ~ .
.: ' , 1~0~02 annular ring, as best illustrated in Figs. 36 and 37. The thickness w of light intercepting member 220 is slightly less than the width W of annular space 203, so that the light intercepting member 220 can move over a small distance within space 203, along the direction of the photographing optical axis. -Elastic body 221 of light intercepting member 220 is provided, along its inner periphery, with a light intercepting lip 223 having a small width which slidably contacts the outer periphery of decorative frame 220.
Reinforcing plate 222 can be secured to elastic body 221, e.g., by partially imbedding the elastic body 221 into connecting recesses, holes or apertures 224 formed in ~ -reinforcing plate 222, which plate is made, e.g., of metal 15 or synthetic resin. The inner lip 223 is extremely flexible `
and is capable of moving in either direction axially of a lens barrier block about which it is positioned. The lip can thus pIay a minor role in reducing rebound of the ;
barrier block after it ceases movement in a first axial 20 direction. -~ ig. 38 illustrates a second embodiment of the annular ring illustrated in ~igs. 36 and 37, in which two spaced light intercepting lips 223 trather than merely one) are formed on the inner periphery of annular light intercepting member 220 in order to increase the light interception effect of the apparatus. These lips are spaced from each other in a parallel fashion and form a generally annular U-shaped, ~inwardly directed annular flange for the light intercepting member. Elastic body 221 is used to cover the outer periphery of reinforcing plate 222 in such structure.
Alternately, it would be possible to replace annular light intercepting member 220 with a conventional 0-ring structure, which would be the simplest manner of intercepting light and preventing it from reaching undesirsd areas within the camera.
With such a light intercepting mechanism, undesirable .
. 133~2 light rays will not enter the camera lens system through the circumference of the front lens group frame 16 and/or the rear lens group frame 18, nor through the front annular opening between the lens barrel and camera cover.
G. FPC Board Guide and Anti-Reflection Mechanism The FPC board guide and its associated anti-reflection mechanism of the are best illustrated in Figs. 39-43.
In a lens shutter type of camera as in the present invention, it is necessary to provide operational signals to shutter block 23 on lens barrel block 1 from the body of the camera. Shutter block 23 is supported by support frame 22 of front lens element group Ll, and accordingly moves together with front lens element group Ll along the direction of the optical axis. In order to send operational signals from the camera body to the shutter block 23 which moves in such an optical axis direction, in response to outputs of the distance measuring device, i.e., the range finder, and, e.g., the exposure control device on the camera body, a flexible printed circuit board (hereinafter referred to as an FPC board) is desirably used. The mechanism for guiding movement of the FPC board and the anti-reflection assembly which are used in conjunction with such bc~ard are described hereinbelow in detail with more specific reference to Figs. 39-43.
FPC board 160 (see Figs. 39 and 40~ provides operational signals to shutter block 23 from one side of the camera body. This board is made from a flexible synthetic resin sheet having f a predetermined printed circuit pattern thereon; in general, such FPC boards are well known.
As illustrated in Fig. 39, FPC board 160 has a connecting pattern 161 at a front end of the board to which shutter bloc}c 23 can be electrically connected, and a rear connecting pattern 162 to which a CPU (a central processing ~; unit which is not illustrated in the drawings) which is -provided in the camera body can be electrically connected.
FPC board guide plate 163, which guides FPC board 160, is .- `' ~' , 7 ~ 3 ~
P5713Sol - 54 secured to the camera body at a base or rear portion thereof, and extends into a space between cam ring 14 and decorative frame 22, forwardly of lens barrel block 1.
Securing clips 166 are provided for attaching the FPC board 163 to the guide plate, and clamping members 167 (see Fig.
41) are provided for attaching the FPC board to the front portion of a camera body frame, e.g., which is die cast, or tG the rear portion of a lens barrel frame(base 6).
A bent guide 165 is provided on the front end of FPC
board 163; this bent guide comprises a pair of front and rear guide pins 168 and 169. These guide pins are preferably stationary (although it is conceivable that rollers could be used instead) and are adapted to maintain the curvature of the FPC board 163 along an immovable bent portion 160a of the board, at which point the board extends ~orwardly from the camera body and is bent in opposite directions so as to extend towards the camera body. FPC
board 160, which is bent around guide pin 168, extends rearwardly into the gap between guide.pin 169 and FPC board guide plate 163, and is again freely bent forwardly by or at a movable bent portion 160b.
It should be appreciated that the relative positional relationship between guide pins 168 and 169, and FPC board 160, is constant, irrespective of the movement of shutter block 23 forwardly and rearwardly in an axial direction.
Accordingly, guide pins 168 and 169 are preferably immovable pins which are not rotatable. Alternately, it is possible to replace these pins with guide rods or shafts over which the FPC board will be bent in opposite directions.
As shutter block 23 moves forwardly and rearwardly, the movable bent portion 160b of the FPC board also moves forwardly and rearwardly. Although the extension of the FPC
board 160 extends rearwardly from the board guide plate 163, as shown in Figs. 39 and 40, actually the rear extension of FPC board 160 can be bent forwardly along, and by, a bent guide 170 of guide plate 163 in order to move the board ; ! ` "
~33~1~a2 P5713S01 _ 55 towards the front part of the camera body.
The inner surface of FPC board 160 faces the gap between the front lens group frame 16 (as well as decorative frame 22) and rear group lens frame 18, and there is therefore a possibility that rays of light which are incident ~pon the lens system will be reflected b~ ~PC board 160, resulting in undesirable internal reflection. In order to prevent such internal reflection, an anti-reflection material or apparatus can be (and should be) provided on FPC
board 160.
Several alternate solutions can be used to provide anti-reflection means on the FPC board 160. As one solution, FPC board 160 can be formed from a dull-fini-sh, blac~ synthetic resin material. Alternately, the FPC board 160 can be provided along its inner surface, i.e., on its surface which is adjacent to the optical axis o~ the camera, with an anti-reflection sheet 171, as illustrated in Fig.
43. Such a sheet can comprise, e.g., a dull-finish black paper or the like, and is adapted to be placed on the FPC
board 160. Preferably, the anti-reflection sheet 171 is simply loosely superimposed on the FPC board without being adhered to the board in order to provide flexibility against deformation due to expansion and shrinkage of the material.
Sheet 171 lies on the FPC board in the area between bent portions 160a and 160b of FPC board 160. A third solution is to coat at least the inner surface of FPC board 160 with an anti-reflective laver.~
with the guide mechanism of the FPC board and with the anti-reflection mechanism which are noted above, when the zooming motor 5 is driven to rotate in order to rotate cam ring 14, front lens group frame 16 and rear lens group frame 18 will be moved in directions along the optical axis in accordance with the cam grooves 20 and 21 on cam ring 14 in order to effect a zooming operation, and can be moved into a position in which the camera is in its macro setting or mode. Movement of the front lens group frame 16 causes . ,.
~ ~r ~
133~D2 P5713S01 ~ 56 _ shutter block 23 to move in the same direction, so that FPC
board 160 will be extended in accordance with movement of the shutter block 23. Extension of the board is made possible by displacement of movable bent board portion 160b.
5 Specifically, FPC board 160 is integrally connected to the CPU in the body of the camera at rear end connecting pattern or portion 162 (see Fig. 39) and the intermediate portion of the FPC board is guided by FPC guide plate 163. The immovable bent portion 160a of the FPC board 160 is 10 immovably guided by guide pins 168 and 169; and, accordingly, when the front end connecting pattern 161 of FPC board 160 moves in accordance with or in response to movement of shutter block 23, only the movable bent board portion 160b will be displaced forwardly and rearwardly in 15 order to absorb the movement of shutter block 23, as illustrated in Figs. 40 and 42. In this fashion, FPC board 160 can be surely guided within the annular space 164 located between cam ring 14 and decorative frame 22 (Fig 41).
Since the FPC board 160 has an anti-reflection structure as disclosed above, internal reflections which would otherwise cause an undesirable phenomena, e.g., a . -flare or a ghost, will not ~ccur.
H. Detection Mechanism for Detectinq Information Relatinq to -~
25 the Position of the Zoom Lens As noted previously, in a lens shutter camera formed in accordance with the present invention, the photographic optical system ``is moved along the optical axis ~by the rotation of cam ring 14, so that the focal length of the 30 photographic optical system will vary, and so that the ~ optical system will move from one extreme angular position ;~ of the cam ring into the macro setting position, and from the other extreme angular position of the cam ring into a lens (totally) collapsed position. In sush a lens shutter 35 type of camera, which includes a zoom lens, it is necessary, e.g., to detect the focal length of the photographic optical ~33~2 system, the macro setting position, and the two extreme positions of the cam ring in order to indicate the focal length, to control the exposure which varies in accordance with the F number, and to control the direction of rotation of the motor which drives the cam ring.
In the present invention, the above information, i.e., relating to the focal length and the two extreme positions of th zoom lens, can easily be detected by code signals on the single flexible code plate 90 which is provided on cam ring 14. Specifically, code plate 90, as illustrated in Fig. 44, is provided on cam ring 14 (which is shown in Fig.
1) and is brought into sliding contact with a brush 92 (Fig. -44) which is secured at its base end to a stationary frame 91 positioned on the outside of cam ring 14. This is well 15 illustrated in Fig. 1. ~ -Fig. 44 illustrates the developed code plate 90, in a flattened condition, in which the upper half of the drawing illustrates the cam profiles of zooming cam groove 20 and 21 of cam ring 14, .and cam grooves 55, 56 and 57 of cam plate 53, respectively. Brush 92 includes a common terminal C and independent (bristles) terminals T0, Tl, T2, and T3. When each of terminals T0-T3 is electrically connected to the conductive lands 93 of code plate 90, a signal "0" is issued, and when each of the terminals T0-T3 are not electrically connected to conductive lands 93, a signal "1"
is issued. The angular position of cam ring 14 can be detected by the combination of signals "0" and "1". A
plurality of dummy terminals 94 are formed in conductive lands 93. The purpose of the dummy terminals, which are formed from the same material as conductive lands 93, is that the flexible code plate bent about the cam ring, and in order to improve the physical strength of the plate and ~;~ still provide an area without electrical contact the dummy terminals were so positioned to increase flexibility while preserving strength. Additionally, these dummy terminals provide (non-conductive) lands upon which the terminals T0-, _ ' ! ~
~330~a2 P5713SOl - 58 T3 of the brush can ride as the cam ring is rotated.
The four bit information received from termi~als TO-T3 are provided as zoom code data ZPo, ZPl, ZP2, and ZP3, respectlvely, of a zoom code encoder, as is clearly illustrated in Fig. 45. This figure comprises a table of combinations of signals "o" and "l", in which the angular position, i.e., PoS, of cam ring 14 is divided into 13 steps between "0" and "9", and "A", "~", and "C", respectively, which are hexadecimal numbers. The number "0" designates a locked position, and the "C" position designates a position in which the camera is in its macro mode. Between the loc~ed position and the macro position, there are nine focal length positions fo-f7'. The locked position and the macro position correspond to the two extreme angular positions of the cam ring 14. Zooming motor 5 is controlled so that the cam ring 14 will not rotate beyond the two extreme positions. These angular or rotational positions are shown on the code plate in Fig. 44.
Rotation of cam ring 14 is controlled by the mode changing switch 101 and the zoom switch 102, which are illustrated in Figs. 47-50, in accordance with positional information of cam ring 14 as determined by code plate 90.
The arrangement of mode changing switch 101 and zoom switch 102 on the camera body is illustrated in Figs. 46-48.
A release button 99 is provided on the upper surface of the camera which can be pushed by one step to turn a photometry switch into an ON position, and which can be pushed by two steps to turn a releasé switch into an ON position (neither -~
of these two switches are shown in the drawings, however).
Mode changing switch 101 is a transfer switch which can occupy 3 positions, i.e., a lock position (LOC~), a zooming position (i.e., ZOOM), and a macro position, i.e. (MACRO). -~
As illustrated in Figs. 49-50, when macro button 101a is not depressed, switch lever 101b can move between the LOCK and ~-ZOOM positions. When macro button 101a is depressed, however, and when switch lever 101b slides onto the upper ~333l~L02 surface of macro button lOla, the macro mode of the camera will be set. Figs. 49 and 50 are cross-sections of the macro and ~oom-lock switches, respectively. When in the LOCK position, neither the releasing operation nor the zooming operation of the 7oom lens can be effected. In the ZOOM position, however, the release operation and the zooming operation can be carried out. In the MACRo position, the releasing operation can be performed but the zooming operation cannot be effected.
10Fig. 51 illustrates an alternate arrangement of the zoom switch, in which the zoom lens is moved towards a telephoto position when a telephoto button T is pushed and towards a wide angle position when a wide angle button W is pushed.
15Zoom switch 102 occupies a neutral position, i.e., it is placed into an OFF position, when no external force is applied to the switch; and it can be manually moved into a wide angle position, i.e., a WIDE position, and into a . telephoto position, i.e., a TELE position, which positions are located on opposite sides of the neutral "OFF" position.
Zooming motor 5 can be rotated in both forward and reverse directions by switching the position of zoom switch 102 . between the WIDE and TELE positions.
Mode changing switch 101 and zoom switch 102 actuate the camera of the present invention as detailed hareinafter.
In actual use, positional information relating to the position of cam ring 14 which is indicated by code plate 90 will be used.
1. For the LOCK position of the mode changing switch 101, zooming motor 5 is reversed to rotate cam ring 14.
When the angular position POS of cam ring 14 becomes "O"
(see Figs. 44 and 45) as detected by code plate 90 and brush 92, zooming motor 5 will stop rotating.
2. For the MACRO position of the mode changing switch ;~ 35 101, zooming motor 5 rotates in the forward direction and ~ stops rotating when POS reaches the "C" position.
1 3 ~ 2 3. For the ZOOM position of the mode changing switch 101, zooming motor 5 reverses when zoom switch 102 is in the WIDE position, and rotates in the forward directlon when the zooming switch is in the TELE position. Zooming motor 5 will stop rotating when POS reaches the "A" position, when the zoom switch is in the TELE position. When the zoom switch is in its WIDE position, zooming motor 5 will continue reversing for a predetermined short span of time after PoS reaches the "1" position. Af'ter this time, zooming motor 5 will begin rotating in a forward direction and will stop rotating when PoS becomes 2.
When zoom switch 102 is turned to the OFF, i.e., neutral, position, during rotation of zooming motor 5, the zooming motor will immediately stop rotating when the zoom switch is in the TELE position, and will stop after it rotates in the forward direction for a predetermined short period of time when it is in the WIDE position, respectively.
Details of several of the positions will now be described. ' POS 1: Since the code signals change at the LOCK
position and at the extreme WIDE position, these extreme positions are detected. More precisely speak'ing, the LOCK
position is not "POS 0", but is instead a point which is located between POS 0 and POS 1. However, when the camera is in the LOCK position, the brush is in POS 0, in a location very close to POS 1. Similarly, the WIDE extreme position is apoint'between POS 1 and POS~2. However, when the camera is in the extreme WIDE position, (which is not a wide zone), brush 92 is in POS 2, which is very close to POS
1. Accordingly, POS 1 denotes a range in which the cam ring 14 moves from the extreme WIDE position to the LOCK
position, and vice versa.
:~POS f7 ': This zone is provided for absorbing the ~35 backlash of cam ring 14 ~ie., backlash from movement of the ;~lçns system). Specifically, as illustrated in Fig. 45, f y '~ '`' l33a~a2- -during rotation of the cam ring from PoS o towards POS c, the cam ring will stop immediately when a stop signal is given, i.e., when the zoom switch is turned to an off position. To the contrary, rotation of the cam ring from PoS C towards POS o causes the cam ring 14 to reverse slightly after it overruns its desired position by a predetermined displacement, and then stops the cam ring at a first changing POS point. POS f7' is the extreme TELE
position, and, accordingly, when cam ring is in its extreme 10 TELE position (with the TELE zone being a zone in which the cam ring operates at the TELE exposure), the brush will be located at position POS A, which is very close to POS 9.
The focal length information or the F number information are fed to the shutter by the code plate and the brush.
Accordingly, the same focal length information is fed at the TELE zone and the TELE extreme positions. This is the reason that POS 9 is represented by f7 and POS A is represented by f7' in order to distinguish it from f7. The zone f7' is quite small, and accordingly the zone f7' can essentially be considered identical to the extreme TELE
position.
POS B: In a fashion similar to POS 1, this zone is provided to distinguish the extreme MACRO and TELE
positions. Unlike POS 1, in which the WIDE extreme position is a changing point between P~S 1 and the- WIDE extreme position, and PoS s is an extreme TEL~ position representing changing points between POS 9 and POS A, respectively.
POS 2 - PoS A: These are intermediate focal length positions which comprise a plurality, e.g., 9 in the illustrated embod`iment, steps.
The CPU then checks the code information and the setting positions for the various switches when they are ~turned into their ON positions. If the mode changing switch `-~ i5 in a zoom position, no zooming will be necessary when the -~ 35 cam ring i~ in any position between and including POS 2 and POS A. If, however, the mode changing switch is 'n a ,~: ' -;
, ;: ~33~2 P5713S01 ~ 62 position other than the zoom position, i.e., in either the LOCK position, an intermediate position between LOCK and WIDE, an intermediate position between TELE and MACRO, or the MACRO position, zooming operation of the lens will be immediately effected. This is also true when the switch is brought into the zoom position during rotation of the zooming motor in the forward direction and when the switch is brought into the zoom position during reverse rotation of the zoomin~ motor. Specifically, when in the zoom position, whether the zoom code is within the range between and including POS 2 to PoS A (within which range zooming is -~
effected) will be checked by the CPU. If the zoom code is out of the range, no picture can be taken, and, accordingly, the cam ring will be moved into the zooming position. In other words, POS 1 and POS B are areas in which the cam ring is prohibited from stopping and in which a picture cannot be taken.
o~ course, it is clear that the present invention is not limited to the embodiments described above, nor those illustrated in the drawings, and the invention can be modified without departing from the spirit and scope of the claimed invention.
. ~
Claims (63)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A lens shutter type of camera having a zoom lens and a viewfinder optically separate from said zoom lens, said zoom lens driven by a motor, means, associated with said motor, for driving said zoom lens continuously between an extreme wide angle position and an extreme telephoto position, and means, associated with said motor, for driving said zoom lens beyond said telephoto position into a close-up photographic position.
2. A camera in accordance with claim 1, further comprising a stationary strobe assembly.
3. A camera in accordance with claim 1, said zoom lens being movable into at least three different positions.
4. A camera in accordance with claim 1, wherein said zooming lens includes a photographing optical system having at least two separate lens groups.
5. A camera in accordance with claim 1, wherein said motor comprises means for continuously driving said zoom lens into an infinite number of positions of different focal lengths.
6. A camera in accordance with claim 5, wherein said camera includes a finder optical assembly and a strove assembly, said finder optical assembly and said strobe assembly are positionable in a continuous fashion into a plurality of positions in accordance with the position of the zoom lens.
7. A camera in accordance with claim 6, wherein said zoom lens has a barrel block, said means for positioning said finder optical assembly and said strobe assembly in association with zooming movement of said lens includes a flexible code plate which is positioned about a cam ring which surrounds the zoom lens barrel block.
8. A camera in accordance with claim 7, wherein said code plate comprises a plurality of conductive lands, and said camera comprises a conductive brush with a plurality of terminals which are electrically connected to a printed circuit board.
9. A camera in accordance with claim 8, wherein said code plate further comprises a plurality of non-conductive lands.
10. A camera in accordance with claim 7, wherein said code plate is rotatable in a constant axial position.
11. A camera in accordance with claim 1, further comprising a generally cylindrical, rotatable cam ring positioned about said zoom, lens and driven by said motor, said motor and said cam ring together comprising means for zooming said lens along a photographic optical axis.
12. A camera in accordance with claim 11, wherein a sector gear is attached to the outer periphery of said cam ring and comprises means for rotating said cam ring when said sector gear is driven by said motor.
13. A camera in accordance with claim 12, wherein said zoom lens includes a front lens group and a rear lens group, said cam ring having a front lens cam groove and a rear lens group cam groove for slidably receiving pins attached to frames for each of said lens groups.
14. A camera in accordance with claim 13, wherein said front lens group is adapted to be engaged by a pin on a frame which surrounds said front lens, and said rear lens group is adapted to be engaged by a pin attached to a rear lens group frame.
15. A camera in accordance with claim 14, wherein said frame surrounding said front lens group comprises a shutter block and a pin mounted to said shutter block and received in said front lens group cam groove, said front lens cam groove includes a shutter block opening and closing section, and an extreme wide angle position section which said shutter block pin engages when said cam ring travels over an angle .THETA.1, a variable magnification ring travels over an angle .THETA.2, and an extreme telephoto position section, a macro transfer section, and an extreme telephoto position section, a macro transfer section, and an extreme macro fixing section which said shutter block pin engage when said cam ring travels over said angle .THETA.3, wherein said rear lens groove includes an extreme wide angle position section which said rear lens group frame pin engages when said cam ring travels over an angle .THETA.1, a variable magnification section which said rear lens group frame pin engages when said cam ring travels over said angle .THETA.2, and an extreme telephoto position which said rear lens group frame pin engages when said cam ring travels over said angle .THETA.2, and an extreme telephoto position which said rear lens group frame pin engages when said cam ring travels over said angle .THETA.3.
16. A camera in accordance with claim 1, further comprising means for automatically focusing said camera.
17. A camera in accordance with claim 16, wherein said automatic focusing means includes means for measuring the distance of a subject from the film plane of said camera by triangulation.
18. A camera in accordance with claim 17, further comprising means for extending the base length of said distance measuring device in a macro camera mode when said lens is located beyond an extreme telephoto position, said base length extending means comprising an optical wedge which is movable to a position along the axis of a light receiver forming part of said distance measuring means.
19. A camera in accordance with claim 18, wherein said optical wedge comprises a prism.
20. A camera in accordance with claim 19, wherein said prism is positioned within a frame having a front surface and a rear surface, a top, a bottom, and two sides, when in its moved position wherein a substantially central portion of said frame is positioned along the optical axis of said light receiver, said prism being positioned in an upper portion of said frame, said front wall having an elongated opening for permitting light to enter said frame, said rear wall having an elongated slit comprising means for permitting light to exit said frame.
21. A camera in accordance with claim 20, wherein said rear wall slit is located substantially along said light receiver optical axis, and said prism is positioned between said slits and thereby comprises means for refracting light entering said front wall slit and for conducting said light, via internal reflect on, through said rear wall slit.
22. A camera in accordance with claim 17, further comprising means for extending the base length of the subject distance measuring device when said camera is placed into a macro photographic mode.
23. A camera in accordance with claim 18, wherein a rotatable cam ring is attached to said zoom lens, said cam ring including a driving gear positioned thereon, said driving ring including a camming projection, said projection comprising means for engaging a lower end of said optical wedge and means for pivoting said optical wedge, against the biasing force of a spring attached to said optical wedge, into the optical axis of said light receiver.
24. A camera in accordance with claim 1, wherein said movable lens is positioned within a lens barrel block, said lens barrel block having a sector gear positioned about at least a portion of said block.
25. A camera in accordance with claim 24, wherein said sector gear is positioned about a rotatable cam ring and extends over more than 180° about said ring and said block.
26. A camera in accordance with claim 25, further comprising a first pinion attached to a shaft of said motor, said first pinion operatively connected to said sector gear to rotatably drive said cam ring.
27. A camera in accordance with claim 26, further comprising a second pinion engaging said sector gear, said sector gear comprising means for rotatably driving said second pinion.
28. A camera in accordance with claim 27, further comprising at least two additional gears driven by rotation of said second pinion.
29. A camera in accordance with claim 24, further comprising a movable cam plate and means for moving said cam plate in a linear fashion in response to rotation of said sector gear.
30. A camera in accordance with claim 29, wherein said cam plate comprises a rack attached to a flat portion of said cam plate, said rack extending downwardly from said flat cam plate portion in a substantially perpendicular fashion.
31. A camera in accordance with claim 30, wherein said cam plate includes a plurality of camming grooves.
32. A camera in accordance with claim 1, wherein said zoom lens comprises a front lens group and a rear lens group, said camera comprising a shutter block mounted around said front lens-group.
33. A camera in accordance with claim 32, wherein only said front lens group zooms in order to focus said camera.
34. A camera in accordance with claim 32, wherein both of said lens groups are capable of moving over different linear displacements.
35. A subject distance measuring device for an automatic focus camera having a macro photographic position, said subject distance measuring device comprising means for determining the distance of a subject from a film plane in said camera, said camera having a photographic optical system which is automatically focused in accordance with the detected distance of said subject, said optical system being movable to an extreme telephoto position and to a macro position beyond said extreme telephoto position, said subject distance measuring device comprising an optical element and means for selectively inserting said optical element into the optical path of said subject distance measuring device.
36. A measuring device in accordance with claim 35, further comprising a light emitter and a light receiver wherein said optical element is selectively positionable between said light receiver and said light emitter to optically extend the base length between said two elements when said photographing optical system is moved into said macro position.
37. A measuring device in accordance with claim 36, wherein said optical element comprises a total internal reflection prism having at least two totally reflective surfaces for moving light incident on said prism in parallel in order to extend said base length.
38. A measuring device in accordance with claim 37, wherein said optical element comprises means for intersecting the optical axes of said light emitter and said light receiver at a finite distance
39. A measuring device in accordance with claim 38, wherein said optical element comprises a correction flag which is pivotably connected to said camera at one end and which has a second, free end in which said optical element is positioned.
40. A measuring device in accordance with claim 39, wherein said camera further comprises a spring for continuously biasing said flag into a retracted position away from the optical path of the light receiver, and means for rotating said flag to overcome the bias of said spring and for positioning said optical element in the optical path of said light receiver.
41. A measuring device in accordance with claim 40, wherein said camera includes a rotatable driving ring and said flag rotating means comprises a projection on said driving ring which is adapted to engage and rotate the pivoted first flat end.
42. A measuring device in accordance with claim 39, wherein said flag is flexible.
43. A measuring device in accordance with claim 35, wherein said optical element comprises a prism positioned in a frame, said frame having a front surface and a rear surface and including an elongated slit on an upper portion of said front surface and an elongated slit on a central portion of said rear surface.
44. A photographing zoom lens positionable within a camera, said zoom lens having at least a first lens group and a second lens group, and means for positioning said zoom lens in an extreme wide angle position and an extreme telephoto position, said zoom lens further comprising means for moving only said first lens group into a position beyond said extreme telephoto position in order to provide close focusing of said lens when the camera is placed into a macro photographic mode.
45. A zoom lens in accordance with claim 44, wherein said first lens group is located closer to the subject being photographed than is said second lens group.
46. In a camera having a zoom lens positionable in an extreme wide angle position, an extreme telephoto position, a plurality of variable magnification positions therebetween, and a macro photographing position located beyond said telephoto position, an autofocus assembly comprising a light emitter and a light receiver, said light receiver comprising a position sensing device, wherein said position sensing device comprises a first area which is used to sense the position of a subject during automatic focusing of said camera for all lens positions except said macro position, and a second area closely adjacent to said first area which comprises means for sensing the position of a subject during macro focusing of said camera.
47. A camera in accordance with claim 46, wherein said first and second areas are identical.
48. A camera in accordance with claim 46, wherein said first and second areas are overlapping.
49. A camera in accordance with claim 46, wherein said auto focus system comprises an optical wedge which is positioned in front of said light receiving means when said lens is in said macro focusing position.
50. A camera comprising:
(a) a zoom lens which is movable between an extreme wide angle position, an extreme telephoto position, a plurality of variable magnification positions between said two extreme positions, and a macro focusing position beyond said telephoto position;
(b) a device for measuring the distance of a subject from the film plane of said camera, said measuring device including a light receiver and a light emitter;
(c) an optical element which is selectively positionable in the optical path between said light receiver and said light emitter;
(d) means for driving said lens; and (e) means for positioning said optical element between said light receiver and said light emitter when said lens is driven into said macro position.
(a) a zoom lens which is movable between an extreme wide angle position, an extreme telephoto position, a plurality of variable magnification positions between said two extreme positions, and a macro focusing position beyond said telephoto position;
(b) a device for measuring the distance of a subject from the film plane of said camera, said measuring device including a light receiver and a light emitter;
(c) an optical element which is selectively positionable in the optical path between said light receiver and said light emitter;
(d) means for driving said lens; and (e) means for positioning said optical element between said light receiver and said light emitter when said lens is driven into said macro position.
51. A camera in accordance with claim 50, wherein said lens driving means comprises a motor and means for drivably connecting said motor to said lens.
52. A camera in accordance with claim 50, wherein said optical element has a stem attached to a base end thereof, and said positioning means comprises a camming projection which rotates when said lens moves along the photographing optical axis.
53. A camera in accordance with claim 52, wherein said camming projection comprises means for pivoting said optical element into said light path between said light receiver and said light emitter by abutting said base end of said optical element.
54. A camera in accordance with claim 53, further comprising a recess adjacent to said camming projection, said recess comprising means for permitting said base end to turn prior to engaging said camming projection.
55. A camera in accordance with claim 54, wherein said camming projection and said recess are located on a driving ring engaged with said motor via a pinion.
56. A camera in accordance with claim 54, wherein said stem is flexible and maintains said optical element in a substantially vertical upright position when located in the optical path between said light receiver and said light emitter.
57. A camera in accordance with claim 56, wherein said optical element is positioned within a mask which is attached to said stem, said mask having first and second opposite sides and a stop attached to said second side, said stop being adapted to engage a motor support plate when said optical element is located between said light emitter and said light receiver.
58. In an autofocusing system for measuring the distance of a subject from a reference plane of a camera, comprising a light emitter and a light receiver spaced form said light emitter by a fixed base length, means for optically extending the base length of said autofocus system, said extending means comprising a means for inserting an optical element into the path of light entering said light receiver, said optical element comprising a prism positioned within a frame having a front wall and a rear wall each said wall having a slot therein, said slots being spaced from each other by a predetermined distance in a direction perpendicular to an optical axis or light entering said light receiver.
59. An autofocus system in accordance with claim 58, further comprising means refracting light entering said front wall slot for conducting said light by internal reflection through said rear wall slot to said light receiver.
60. An autofocus system in accordance with claim 58, wherein said inserting means is responsive to said camera being placed in a macro photography mode.
61. An autofocus system in accordance with claim 59, wherein said front wall slot is spaced from the optical axis or said receiver and said rear wall slot is located along the optical axis of said receiver.
62. An autofocus system in accordance with claim 58, wherein said optical element comprises a total internal reflection prism having at least two totally reflective surfaces for moving light incident on said prism in parallel in order to extend said base length.
63. A lens shutter type of camera having a zoom lens driven by a motor, means for driving said zoom lens continuously between an extreme wide angle position and an extreme telephoto position, and means for driving said zoom lens beyond said extreme telephoto position into a close up photographic position.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000616420A CA1330402C (en) | 1986-05-12 | 1992-06-25 | Lens shutter camera including zoom lens |
Applications Claiming Priority (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61108279A JPS62264030A (en) | 1986-05-12 | 1986-05-12 | Auto-focus camera capable of close photographing |
| JP61-108279 | 1986-05-12 | ||
| JP61150995A JPS636532A (en) | 1986-06-26 | 1986-06-26 | Automatic focusing camera capable of proximity photographing |
| JP61-150995 | 1986-06-26 | ||
| CA000536919A CA1312231C (en) | 1986-05-12 | 1987-05-12 | Lens shutter camera including zoom lens |
| CA000616420A CA1330402C (en) | 1986-05-12 | 1992-06-25 | Lens shutter camera including zoom lens |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000536919A Division CA1312231C (en) | 1986-05-12 | 1987-05-12 | Lens shutter camera including zoom lens |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1330402C true CA1330402C (en) | 1994-06-28 |
Family
ID=27167712
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000616420A Expired - Lifetime CA1330402C (en) | 1986-05-12 | 1992-06-25 | Lens shutter camera including zoom lens |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1330402C (en) |
-
1992
- 1992-06-25 CA CA000616420A patent/CA1330402C/en not_active Expired - Lifetime
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| MKEX | Expiry | ||
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