CA1329887C - Lens shutter camera including zoom lens - Google Patents

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

13.~9887 -- 1 -- .
LENS SHUTTER CAMERA INCLUDING ZOOM LENS
BACKGROUND OF THE DISCLOSURE
The present application is a di~isional of co-pending Canadian Application Serial 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 or photographing optical system, and in which a finder optical ~y6tem 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.

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. Backaround Art Generally, in conventional lens shutter (i.e., between the lens ~hutter) type~ of auto-focus cameras, it is impossible to vary the focal length of the photographic optical system.
Other lenB ~hutter types of auto-rocus cameras comprise a two ~o¢al length system, in which a lens is provided for varying the focal length and can be selectively inserted in the photographing optical system. In such a system, two focal lengths are pro-vided7 however, it is pos~ible to use only the two focal lengths provided, e.g., a wide angle and a telephoto range for the zoom len~, or, e.g., a standard range and a telephoto range for the zoom len~. While taklng advantage o~ such dual focal lengths, it i~ lmpo~ible to cover the range o~ focal lengths between the two extreme focal lengths, or between a wide angle and a medium telephoto ~ocal length. Under such circumstances, taking pic-tureB with the u~e o~ a zoom lens has hereto~ore only been ~:
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13~8~7 possible by using a single lens reflex camera.
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However, single lens reflex cameras are more expensive and heavier than lens shutter type cameras, and, accordingly, it is not easy for a photographer who is unfamiliar with 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 eingle lens reflex cameras which are relatively bulky and heavy, as noted above, have only two alternate choices: (a) a relatively ~mall, light lens shutter type of automatic camera which has hereto~ore not been capable of controlling the focal length of the photographing optical system; or (b) a dual focal length type o~ auto-focus camera in which only two extreme focal lengths can be u~ed.

In accordance with one aspect of the invention, a light blocking mechanism used in a lene shutter camera having a rotatable cam ring with at least one camming groove therein, a mechaniem comprises at least ons light intercepting member poeitloned about the periphery o~ the cam ring. The light intercepting member thereby comprieee means for covering each of the cammlng grooves and prevents light from entering the cam rlng. `

In Accordance with another aspect, in a lens shutter typo o~ oamera h~vlng a cam ring mounted to a eupport member to 3~ b- rot~tAblo ~t ~ conetant axial position, at least one movable ;' , , ~ " ~ ~ ~C~ f~

_ 3 _ 1~2~7 lens barrel movable along an optical axis of a photographic optical system of the camera, a light intercepting member is positioned in a space between th2 front end of the cam ring support member and a front cover having a opening through which the lens barrel is adapted to move.

The present invention provides, in accordance with a preferred embodiment, a light blocking mechanism for use in a lens shutter camera including a rotatable cam ring and at least one camming groove therein, the mechanism comprising at least one light intercepting member positioned about the periphery of the cam ring, the member thereby comprising means for covering each camming groove and for preventing light from entering the interior or the cam ring.

In accordance with a further embodiment, in a lens shutter type o~ camera having a cam ring mounted to a support member to be rotatable at a constant axial position, at least one movable lens barrel movable along an optical axis of a photo-graphic optical ~ystem of the camera in association with rotation o~ the cam ring, a light intercepting member positioned in a pa¢e between a front end o~ the cam ring support member and a ~ront cover having an opening through which the lens barrel is adapted to move.

In accordance with yet another embodiment o~ the lnvention, ln a lens shutter camera having a lens comprising a lene barrel movable along the optical axis o~ the lens, and an annular member rotatable about the lens barrel, such that - rotation o~ the annular member is operative to move the lens barrol along the optlcal axi~ to change an operational parameter o~ the lons, meanfi ~or minimizing rebound o~ the lens barrel with re-~eot to the annular member and means ~or preventing light ~rom 3~ nt-rlng lnto a ~pace between the barrel and the annular member.

1329~7 DISCLOSURE OF INVENTION
The present invention provides, in a preferred embodiment, a lens shutter type of camera having a subject distance measuring device, a photographing optical system which is driven in response to measurement of the subject distance which is detected by the subject distance measuring device, a finder optical system which is independent of the photographing optical system, and a strobe. In accordance with another preferred embodiment of the present invention, the photographing optical system comprises a zoom lens assembly which is capable of successively varying the focal length of this optical system;
the finder optical system is independent of the photographing optical system and comprises a variable power finder optical lens assembly which is cæpable of varying the field of view of the finder lens assembly, in accordance with the specific focal length of the zooming lens system at any point in time; and the zoom len~ system and the variable power finder optical system are driven by a single zooming motor.

: ~ ~`s 13298~7 With such an arrangement, only the zooming operation and the shutter release operation will be manually effected, resulting in a high quality, compact automatic camera.
The lens shutter type of camera of a preferred embodiment used in the present invention is functionally equivalent, or in fact superior, to a single lens reflex camera, insofar as it incorporates a strobe device, thereby providing a highly systemitized, auto-focus camera which is easy to use and handle.
The strobe device can be of a type, e.g., in which the illumination angle will be fixed, but is preferably a variable illumination angle strobe device which is capable of varying the illumination angle in accordance with, or in response to, the variable focal length o~ the zoom lens system.
In accordance with one embodiment of the present invention, the zoom lens system can either be partially or completely moved in the direction of the optical axis o~ the photographing optical system, beyond one o~ the ~ocal length extremities, when the camera is placed into the macro mode. Another feature o~ one embodiment o~ ths pre~ent invention is that thè
~inder optical system comprises a variable power rinder optical system which includes an optical element which is capable of varying the ~ield of view, the optical element varying the ~ield o~ view in accordance with or in response to the particular ~ocal length o~ the zoom lens system. The finder system include~ an optical element which is capable Or de~lecting the ~inder optlcal axis towards the optical : axl8 o~ the photographing optical system in order to correct parallax in the macro mode o~ the camera.
In accordance wlth yet another ~eature o~ another pre~arred embodlment o~ the present invention, a ctrobe device comprises a variable illumination angle strobe device which is capable o~ varying the strobe .
' 132~7 `-illumination angle in accordance with the focal length of the zoom lens system and in association with or in response to movement or transfer of the zoom lens ' -(photographing lens) system into the macro mode.
The subject distance measuring device of the present invention is capable of detecting the subject distance by a conventional triangulation measuring `
method, which has been adopted to ensure precise detection of the subject distance, even when the camera is in its macro mode; this distance measuring device includes an optical element which is capable of de~lecting the distance measuring light in order to :
optically extend the base length of the measuring device in response to transfer or movement of the zoom lens system into the macro mode.
In one preferred aspect of the present invention ;
a lens shutter type of auto focus camera is provided which has a zoom lens which is continuously movable between an extreme wide angle position and an extreme telephoto position. The lens is movable beyond the ~xtreme telephoto position into a macro or close-up photographing po~ition; and it i8 movable beyond the extreme wide angle position into a closed po~ition in which the photographlng lens is completely collapsed and in which lens barriers are provided to close an opening in a lens barrier block. The ~inder field o~
view and strobe illumination angle in the camera vary ln accordance with the zooming operation o~ the lens, as well as when the picture of a sub~ect is taken in a macro mode at a close distance. Focusing can be automatically controlled in both the macro mode and in any range of the zooming lens. An optical wedge is adapted to be positioned along the optical path o~ the di~tance mea~uring device which ~orms a portion o~ the automatic ~ocuoing ~y~tem o~ the camera. A pri~m i5 adapted to be pivoted into the optical path o~ the - ~lnder optlcal system ln order to correct ~or parallax ; ~ ~
132~8~7 in the macro mode. A cam plate is provided which is driven by a single motor, which also drives the zoom lens via a cam ring; and the cam plate is adapted to drive the finder optical system and the strobe light assembly in accordance with zooming operation of the zoom lens.
In accordance with an embodiment of the present invention there is provided a lens shutter type of camera having a movable zoom lens, the camera further comprising a finder optical assembly, means for moving the finder optical assembly in association with zooming movement of the zoom lens in order to vary the field of view through the finder optical assembly, a strobe assembly, and means for moving the strobè
assembly in association with zooming movement of the zoom lens.
In accordance with another embodiment of the present invention there is provided a lens shutter type o~ camera having a zoom lens driven by a motor, means ~or driving the zoom lens continuously between an extreme wide angle position and an ex~reme telephoto position, and means ror driving the zoom lens beyond the extreme telephoto position into a close-up photographic position.
In accordance with another embodiment o~ the present invention there i~ provided a sub;ect distance measuring device ~or an automatic ~ocus camera having a macro photographic position, the subject distance measuring device comprising means ~or determining the distance o~ a sub~ect ~rom a ~ilm plane in the camera, the camera having a photographic optical system which i~ automatically rocused in accordance with the detocted distance Or the sub~ect, the optical system being movable to an extreme telephoto position and to a ma¢ro po~ltion beyond the extreme telephoto position, the sub~ect distance measuring device oomprising an optical element and means ror :, . .~: ' '' selectively inserting the optical element into the optical path of the subject distance measuring device.
In accordance with a further embodiment of the present invention there is provided a photographing zoom lens positionable within a camera, the zoom lens -~ -having at least a first lens group and a second lens group, and means for positioning the zoom lens in an extreme wide angle position and an 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 a macro photographic mode. . : : -In accordance with another embodiment of the present invention there is provided in a camera having a zoom lens positionable in an extreme wide angle position, an extreme telephoto position, a plurality o~ variable magnification positions therebetween, and a macro photographing position located beyond the :
telephoto position, an auto~ocus assembly comprising a light emitter and a light receiver, the light receiver comprising a position sensing device, wherein the position sensing device comprises a ~irst area which i~ used to sense the position o~ a sub~ect during automatic ~ocusing o~ the camera rOr all lens positions except the macro position, and a second area closely adjacent to the rirst area which comprises means ~or sensing the position o~ a subject during ; 30 macro ~ocuslng o~ the camera.
In accordance with another embodiment o~ the present invention there i8 provided a camera Comprising: ~a) a zoom lens which is movable between : an extreme wide angle position, an extreme telephoto -- po~ltion, a plurality o~ variable magni~ication -- po~ltions between the two extreme positions, and a macro rocusing positlon beyond the telephoto position;
~b) a devic~ ~or measuring the distance o~ a subject ~ . :"'.'' ',.' ' :

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13~8~7 g .: .
from the film plane of the camera, the measuring ~ .
d~vice including a light receiver and a light emitter;
(c) an optical element which is selectively positionable in the optical path between the light . .
receiver and the light emitter; (d) means for driving the lens; and (e) means for positioning the optical element between the light receiver and the light :
emitter when the lens is moved into the macro .:
position.
In accordance with yet another embodiment of the present invention there is provided in a lens shutter type camera comprising a photographic optical system ~ .
having a zooming function and a macro function, an independent finder optical system comprising a first lens group having a negative refractive index and comprising a positive lens and a negative lens, a second lens group comprising a negative lens, a third :.
lens group having a positive refr~ctive index, and a prism which is adapted to be selectively inserted into the optical path between the lenses o~ the first lens group, the ~rism comprising means ~or deflecting the ~:
optical path o~ the ~inder optical system towards the optical axis o~ the photographic optical system when the prism is positioned between the lenses of the ~irst lens group. ' -In accordance with another embodiment of the present invention there is provided a finder optical sy~tem in a lens shutter type o~ camera having a phot.ographing optical system which can occupy a macro photographing mode, the ~inder optical system being independent o~ the photographing optical system and comprioing at least one lens, and an optical element which i~ selectively in~ertable into the ~inder optlcal ~ystem when the photographing optical system i9 in the macro mode, the optical element comprising . :
moan8 ~or correcting parallax by de~lecting the .: :
optical axis o~ the ~inder optical system towards the ' . . :. .. ~ .
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- 1 0 - ~ ' optical axis of the photographic optical system.
In accordance with another embodiment of the present invention there is provided a movable cam plate for a camera which is adapted to be driven by a motor, the cam plate comprising a substantially flat main portion, a downwardly extending rack attached to a rear edge of the main portion, and a plurality of grooves in the main portion.
In accordance with a further embodiment of the present invention there is provided a lens shutter ;
type camera comprising a photographic optical system including a zoom photographing lens with at least one movable lens group for varying the optical length~o~
the system, an independent finder optical system which has at least one movable lens for varying the finder ~ield of view in accordance with the focal length of the zoom lens system, and a variable illumination angle strobe assembly with a lamp which is movable in accordance with the ~ocal length of the zoom lens system, and a driving member which moves in assoaiation with the movement o~ the movable lens group, the driving member comprising means ~or moving the ~inder optical system and the strobe assembly.
In accordance with another embodiment of the present invention there i8 provided a lens cap opening and closing mechanism adapted to be used with a lens support ~rame having an outer periphery, a central aperture, and at least one barrier plate for 8electively closing the central aperture, the mechanism comprising a movable member positioned in a peripheral opening o~ the ~rame, the member being engaged with the at least one barrier plate, and means ~or selectlvely moving the member inwardly Or the ~rame to close the aperture with the at least one ~ barrler plate.
1~ In accordance with another embodiment o~ the pre8ent invention there 1s provided a camera having a -: : ' ' ', ' "

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13~8~7 -- 11 -- .
photographing zoom lens movable into a completely collapsed lens position rearwardly of an extreme wide angle lens position, the lens being supported by an exterior frame having a central photographic aperture and at least one barrier for selectively closing the central aperture, the camera comprising means for closing the aperture with each barrier when the lens is moved into the collapsed lens position, and means for opening the aperture in all other lens positions.
In accordance with a further embodiment of the present invention there is provided a light blocking mechanism used in a lens shutter camera including a -rotatable cam ring with at least one camming groove therein, the mechanism comprising at least one light intercepting member positioned about the periphery of the cam ring, the member thereby comprising means for covering each camming groove and ~or preventing light ~rom entering the interior o~ the cam ring.
In accordance with another embodiment of the present invention there is provided in a lens shutter type o~ camera having a cam ring rotatable at a aonstant axlal position and at least one movable lens barrel movable along an optical axis o~ photographic optical system o~ the camera in association with rotation o~ the cam ring, a light interception member positloned in a space between a ~ront end o~ a cam ring support member and a rront cover having an opening through which the lens barrel is adapted to move.
In a¢cordance with another embodiment o~ the pre~ent invention there is provided in a lens shutter type o~ camera havlng a ~lexible printed circuit board ~FPC) ~or condu¢tlng camera operational signals ~rom a camera body to a shutter bloc~ attached to an axially -: movable lene barrel, a guide plate rOr the FPC, the ;;
gulde plate comprising means ~or guiding movement o~
kho FPC as the lens barrel moves axially.

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132~87 ~

In accordance with still another embodiment of the present invention there is provided a lens shutter type of camera having a flexible printed circuit board (FPC) for conducting operational signals from a camera body to a shutter block attached to an axially movable lens barrel, and further comprising an anti-reflection :
device attached to the flexible printed circuit board.
In still another embodiment of the present invention there is provided a lens shutter type of camera having a photographic optical system having a zoom lens with a rotatable cam ring having cam grooves which are engaged by at least one lens group of the zoom lens~, the at least one lens group being movable along an axis of the photographic optical system to vary its optical length in response to rotational motion of a cam ring positioned about the zoom lens.
In accordance with another embodiment of the . .
present invention there is provided a lens shutter type of camera having a zoom photographic lens movable by a driving motor into a completely collapsed lens position located rearwardly of an extreme wide angle lens position, the lens being supported by an exterior frame having a central photographic aperture, the camera including at least one barrier for selectively closing the central aperture, the camera comprising means for moving the len~ into the collapsed lens po~ition from a non-collapsed position of the lens and means ~or closing the aperture when the lens is 80 movQd~
In accordance with still a further embodiment of the present invention there i~ provided a lens shutter type o~ camera having a zoom lens movable along a photographic axls, a Pinder optical assembly, and a strobe assembly, both of the a~semblies being movable along respectlve axe8 which are ~ub~tantially parallel to tho photographic axis, the lens belng rotatable about the photographic axis, the camera further : ', ' - 12a - 13 2 ~ ~g7 comprising means for converting rotational movement of the zoom lens into movement of the assemblies along the parallel axes.
Other aspects, features and advantages of the present invention 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 ~orming a portion o~ the invention o~ Fig. 1;
Fig. 3 i8 a top plan view of the apparatus of Fig. 2;

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13~887 :-.
P5713SOl Fig. 4 is a sectional view taken a~ong 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 photographlng optical lenses formed in accordance with the present invention; ~-Fig. 7 is a developed view of the camming grooves in a "flattened" cam ring us~d to surround the ~ront and rear lens element groups o~ the photographic optical systé~ o~ the camera o~ Fig. l;
Fig. 8 is an exploded perspective view o~ a lens barrel block used in the camera o~ Fig. l;
Fig. 9 is a sectional view illustrating an optical arrangement ~or ad~usting the ~ocus point o~ the camera when the ¢amera is placed into its macro mode;
Fig. 10 is an enlarged plan view o~ the prism, ~rame ~l.e., mask) and one light recsptor len~ o~ the system o~
Fig. 9; .
20Fig. 11 i5 a ~ront elevatlonal vlew lllustrating the as~embly o~ Flg. 10 : Flg. 12 i~ a se¢tional view o~ an optical arrangement u~sd in a two lens group zooming len5 in the camera ot Fig.
1~
2SFig. 13 ls a s¢hematic view illustrating the light ~ emittor and light receptor o~ a distance measuring device - ~ u~ed in the camera o~ Fig. 1~
~; Fig. 14 1~ a ss¢tlonal view o~ an optl¢al arrangement o~ a ~y~tem ror ad~u~ting the rocal point o~ the ob~ect dlotanae mea~Uring ~ystem when the ¢amera i5 in a ma¢ro modo~
Fig8. 15A - 17A are v~rti¢al sectlonal views o~ a ~ir~t mbodlment or a ~lnder optical sy~tem used in ac¢ordan¢e With tho pr-o0nt invent-~on, in which:
~ 35Flg. 15A i~ a oide plan view Or the ~inder optlcal s~ aooombly when in a wld~ ~leld, ~mall magni~l¢ation po~ltlon~
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~ ' P5713SOl 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; ~-Figs. 15B, 16B and 17B, respectively, illustrate the aberrations of the optical systems of Figs. 15A, 16A and -~
17A, respectively; -Figs. 18A-20B are all vertical sectional views of a aecond embodiment of a finder optical system formed in accordance with the present invention in which:
Fig. 18A iB a plan view of the optical system when the camera is in a wide field, small magnification mode;
Fig. l9A is a plan view o~ the optical system when the camera is in a narrow field, large magnification mode: and Fig. 20A is a plan view o~ the optical system when the camera i5 in a narrow field, large magnification macro mode;
Figs. 18B, l9B and 203, respectively, are all views lllustrating the aberrations ~or the ~inder optical a~sembly when it i~ ln the poeition~ of Figs. 18A, l9A and 20A, reepe¢tively s Fig. 21 is a plan view of a cam plate which can be attached to a portion of the ~inder block and the strobe lamp aseembly o~ the present invention;
Fig. 22 i5 a sectional view taken along line XXII-XXII
O~ Flg. 21;
Fig. 23 is a bacX plan view o~ the cam plate o~ Fig.
21~
Fig. 24 i~ a plan vlew o~ the apparatus o~ Fig. 21 with - th- cam plate removed~
Fig. 25 i8 a sectional view taken along line XXV-XXV o~
~ Flg. a~
- Fig. 26 i~ a sectional view taXen along line XXVI-XXVI
o~ Fig. 25 showing the ~inder plate in a ~irst pooition~
~ Fig. 27 is a sectional view similar to that o~ Fig. 26 .~ . ~.. ..

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, .. ~,', / ~ :1 P5713S01 132~3~7 but illustrating the finder plate in a second, operational position;
Fig. 28 i5 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 ~iews of a first embodiment o~ an optical barrier mechanism, as viewed along a plane which is perpendicular to an optical a~is, 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 lllustrating the optical barrier mechanism when it is in its clo~ed position;
Fig. 33 is a sectional view o~ a second embodiment of an optical barrier mechanism ~ormed in accordance with the present lnvention, the view being slmilar to that o~ the ~lrst embodlment o~ the optical barrier mechanism lllustrated in Fig. 31;
Flg. 34 is a sectional view o~ the optical barrler mechanlsm o~ Fig. 33 in its closed position, similar to the view o~ the embodiment o~ Fig. 32;
Flg. 35 is an exploded perspective view o~ a light lntsr¢eptlng mechanlsm positioned ad~acent to a lens barrel blockt Fig~ 36 i~ a perspective view o~ a light intercepting rlng~
Fig. 37 lo a 5ectional view taken along llne XXXVII-XXXVII o~ Fig. 36~
lg. 38 ls a oectional view o~ a second embodlment o~ a - 35 light lntercepting ring ~ormed ln accordance with the pr~o-nt invention whlch is similar to the vlew o~ Flg. 37;
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132~7 P5713SOl ~ ~:

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;
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 o~ an FPC board guide plate with respect to the space de~ined between the cam ring and a front lens group frame:
Fig. 42 is a side elevational view of an FPC board which i5 illustrated in extension (in dashed lines) and in a de~ormed po~ition ~in solid lines), respectively;
Fig. 43 is a side elevational view of a light intercepting means used in a~sociation with an FPC board;
Fig. 44 is a developed or schematic view of a code plate, with the len~ o~ the code plate and gxooves o~ the cam being illustrated on a ~lattened cam ring, illustrating the ~unctional relationship between conductive land~ on the ¢ode plate and the cam (ring and plate) grooves;
~0 Fig. 45 io a table illustrating the zoom code on the code plate o~ Fig. 44 and the stopping po3itions which are located on the code plate;
Fig. 46 i5 a ~ront elevational view o~ the operational owitcheo o~ a camera ~ormed in accordancs with the present invontion7 Flg. 47 io a back elevatlonal view o~ the camera o~ the preoent inventlon illuotrating a zooming lens operation switch thereon~
Fig. 48 io a top plan view o~ the camera o~ Figs. 46 and 47, llluotrating additional operatlonal swltches~
Fig. 49 io a whematic sectlonal ViQW illustrating a mode changlng witch ~ormed in accordance with the present ~- inventlon ln a ~irst, lnoperative pooition;
Fig. 50 i~ a gectlonal view o~ a mode changing 5witch 3~ and a macro button illu5trated in a second operational pooltiont ',: , "
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- ' P5713Sol -17- 1 3 2 9 ~ ~ 7 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 o~ bright frames thereon;
Fig. 53A is a perspective view of a double-wedge shaped prism use~ in the present finder optical system;
Fig. 53B 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.
~ MODE FOR CARRYING OUT THE INVENTION
The present invention will now be described below in greater detail, with specific reference to the accompanying drawinge which illustrate a variety of embodiment~ and ~eatures o~ the present invention.
! ~ The description will be generally provided in accordance with the ~ollowing general sub headings:
. A. ~he Overall Camera Construction ~or a Lens Shutter t 20 Type o~ Camera B. Distance Measuring Devics, i.e., Range Finder, and Came~a Macro Functioning Thereo~
C. Finder Optical System D. Finder and Strobe Driving Mechanisms E. 3arrier, i.e., Lens Cap, Mechanism F. Light Interception Assembly and Mechanism ¦ G. FPC Board Guide and Antl-Re~lection Mechanism l H. MQchanism ror Detectlng Inrormation Relating to the ¦ Po~itlon o~ the Zoom Len~
. 30 A. QYg~ Camera Construction ~or ~ ~ens Shutter ~YE~ Or I Camera r Th~ ov~rall constructlon o~ a lens shutter type Or oam-ra rormed in accordanc~ wlth the present inventlon is woll illu~tratod in Fig~ 8. A lens shutter type Or 3S oamera rormed in accordancQ with the pre~ent inventlon e~entially compris0s a zoom lens barrel blocX 1, a rinder P5713SOl -18- 132~8~7 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 lo 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 ~urther comprises motor supporting plate portions 6c whlch are positioned perpendicularly with respect to the horlzontal support plate portion 6b. Lens barrel block l i8 supported on lens barrel support plate portion 6a, which has a central opening ~unrererenced) ~or 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 o~ lens barrel block l.
~re~erably, only a single ~uch motor ~e.g., a DC motor) is used to drivingly engage all o~ the movable elements o~ the 6ystem. A distance measuring device includes a light emitter 3 and a light receiver 4, which are secured to the horizontal support plate portion 6b o~ base 6, and which are located on opposlte sides o~ zooming motor 5 ~see Figs. 2 -~ 30 and 3). Flnder block 2 is secured to the right hand portlon o~ horlzontal support plate portion 6b, as vlewed ~rom the ~ ~ront o~ the camera as seen ln Fig. 2. A gear train support i- plate portlon 6e is connected to motor support plate portlon ¦- CC vla apacer C~, as be~t illu~trated in Flg. 3.
~ 3~$ens barrel block l ls adapted to be actuated by ¦ zooming motor 5, and the constructlon o~ thls block wlll be .,:

P5713sol 1 3 ~ 7 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. ~ear 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 gulde 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 geiar 15 i~ provided about a substantial portion (but preferably not ths entire 360) o~ the outer periphery of cam ring 14;
this gear can be attached to the cam ring by conventional meane, e.g., via set screws 15a, as seen ln Fig. 6; this gear i~ adapted to engage, either directly or indirectly, a ~irst pinion 7 ~Fig. 1) which i~ positioned between the gear train ~upport 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 Or rotational movement o~ cam ring 14s a turning recess 44a and cam ~ur~ace 44 are provided ad~acent to each other on ~a ~lat sur~ace portion o~) the gear. The cam ring is it~el~ provided wlth zooming cam grooves 20 and 21 (see Fig.
7) which are ueed to engage the ~ront and rear lens element group~, re~pectively.
Flg. 7 ls a schematlc or developed view Or zooming cam g~oove~ 20 and 21 o~ ring 14. Cam groove 21, u~ed to engage th- ~-ar lon~ element group, lncludes an extreme wlde angle rixlng ectlon 21a, a variable magni~ication ~ection 21b inclin-d upwardly ~a~ seen in Fig. 7) ~rom section 21a, and an extreme t01ephoto ~ixing sectlon 21c. Cam groove 20, 3~ u~ rOr the ~ront lens elemsnt group, lnclude~ a section 20a ~or openlng and closing barrier block 30, a lens ~ k!~, j ` t~ ~ -1~2~8~7 P5713Sol retraction section 20b, an extreme wide angle fixing section 20c, a variable magnification 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 speci~ication, it refers to a "close-up" photographing configuration for the camera. Previously, the term "macro"
has occa~ionally 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 unles~ indicated to the contrary herein.
The total angle 0 1 ~ the rotational displacement of cam ring opening and closing section 20a, lens retraction section 20b, and extreme wide angle ~ixing section 20c of zooming cam groove 20 i8 identical to angle 0 1 f the extreme wide angle fixing section 21a o~ zooming cam groove 21. Angle~3 2 ~ the variable magni~ication, ~.e., variable power,. section 20d o~ zooming cam groove 20 i9 identical to angl~32 ~ the variable magni~lcatlon, i.e., variable power, ~ectlon 21b o~ zoomlng cam groove 21. Further, the total angle ~ 3 o~ the extreme telephoto ~ixing section 20e,~ the macro position ~lxing section 20g, and the macro trans~er section 20~ equal to the angle 0 3 o~ the 2~ extreme telephoto ~lxlng sectlon 21c. In the illustrated embodiment, the zooming range is between approximately 35mm and approximately 7Omm.
A roller 17, as lllustrated in both Figs. 6 and 8, is pooltlonot wlthin zooming cam groove 20: this roller is attached to a ~ront lens group ~rame 16. A roller 19 o~
rear len5 group ~rame 18 i~ posltioned wlthin zooming cam groo~o 21, agaln as lllu~trated in Flgs. 6 and 8. Front lon~ group ~rame 16 and rear lens group ~rame 18 are movably guided by guldo rods 12, and a decorative ~rame 22 and 3g ~hutt~r block 23 are secured to the ~ront lens group ~rame 16 via ~et screws 22a, A~ best seen in the exploded view o~

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- 21 - 13298~7 -Fig. 8, as well as in the cross-sectional view of 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), so 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 Ll 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 ~rom the distance measuring device, as described hereina~ter, via a pulse motor which is incorporated within the camera body and which is adapted to open shutter sector 23b, which has been closed ~or a predetermined time, and to thereafter return lens ~eeding lever 23a into its original position arter the shutter has again closed. This type o~ shutter block is disclosed, e.g., in unexamined Japanese Published Patent Application ~KOK~I) No. 60-235,126 dated November 21, 1985. The pre~ent camera utillzes such a shutter block in the ~undamental way disclosed therein.
Finder block 2 includes ~inder assembly 8 and ~trobe a~sembly 9. The ~inder devlce and the strobe d-vice are adapted to vary, respectively, the ~ield of ~lnder view and the illumination angle, i.e., the intensity o~ the strobe, .
~.' .

132~7 P5713SOl --22~
in accordance with variance in the focal length of the lens barrel block 1. 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 ;
~irst 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 10 train 52 adjacent a rear end of the shaft. The reduction ;~
gear train includes a final gear 52a which meshes with a rack 53a o~ movable cam plate 53. This substantialIy flat cam plate 53 is slidable in right and left hand lateral - ~ `
directions, as viewed in Fig. 1, and includes a downwardly bent portion 53b at its rear end, as best shown in Fig~ 1.
Rack 53a is ~ormed on the lowér end of bent portion 53b of ¢am plate 53. Reduction gear train 52 i8 adapted to reduce rotatlon o~ gear 15 in order to restrict or limit the lateral movement o~ cam p.late 53. The cam plate is provided with a variable power cam groove 55 ~or guiding movement o~
~inder device 8, a parallax correction cam groove 56, and a strobe cam groove 57 ~or guiding movement of strobe device 9 .
The lens system used in rinder optical assembly 8 essentially comprises a subject lens group L3, an eyepiece group L4, and a movable variable power lens group L5, and ~urther comprises a de~lection prism Pl which is used when the camera is placed into the macro or close-up mode.
Variable power lens group L5 makes the image picture ~lze, which is adapted to vary in accordance with the variable power operation o~ lens barrel block 1, be coincident wlth the rield o~ view in ~inder dsvice 8.
D-~lectlon pri~m Pl will enter the optical path of the ~inder len~ ~y~tem only in the macro mode, in order to ad~ust parallax whlch otherwlse occurs in such mode.
Speci~lcally, parallax whlch lnevltably occurs when using ;.
, ,1 (...;

13~9~8~ ~
P5713SOl lens shutter type of cameras will in~rease 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 de~lect 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 o~ light rays when the deflection prism Pl is located along the optical axls of the camera. As described hereinafter, the wedge prism which is used is pre~erably selected to be a double wedge prism, which varies in width in both the vertical and in the horizontal directions, as clearly lllustrated in Figures 53A, 3 and C. The use of ~uch a prlsm bends the light rays downwardly and rightwardly, to move them into substantial alignment with the photographic optical axls.
Strobe as5embly 9 restricts or limits the illumination angle when the ~ocal length o~ the photographing lens is large, namely, as the zoom lens is ~ed ~orwardly; and the strobe assembly 9 is moved to increase the illumination angle ln the macro mode, ln order to decrease the amount o~
light which reaches the subject. In the embodiment lllustrated, etrobe devlce 9 includes a ~ixed Fresnel Lens ~6, a movable concave re~lector 59, and a xenon lamp 58 Which can be moved along the dirsctlon o~ the optical axis o~ the etrobe. Alternately, a simple strobe could be used ln Which the illumlnation angle would be ~ixed. Although ~ euoh ~ ~trobe arrangement ls posslble, it is pre~erable to -~ move the lamp in the optical axl~ dlrectlon in accordance With movement o~ the zoom lens ln order to optimlze the 3g guantity o~ light glven to a sub~ect during photography, dependent upon the po51tlon occupied by the photographlng ':," :.
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r P5713Sol _ 24 - 1 3 2 9 8 ~ 7 optical system in the zoom lens.
B. Distance Measurinq Device, i.e.. Ranqe Finder, and Camera Macro Function ~efore looking in a detailed fashion at thé distance 5 measuring device of the present invention and its , relationship to the macro function of the camera, the , relationship between 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. , Fig. 12 illustrates a relatively simple construction ~ ,' for a two lens group zoom lens. In such a construct~on, the distance o~ the subjec,~ ~nd the displacement of the zoom lens have a relationship as follows: ,,,' U~ 2+X/fl+fl/X) + HH + ~ ....... (l), wherein: ' U equals the distance o~ a sub;ect ~rom the ~llm plane;
21 equals the ~ocal length o~ the ~irst lens groupt X equals the displacement o~ the zoom lens; ~, , equals the principal point distance; and ~ equals the distance between the ~ocal point o~ the ~irst , ,, lens group and the ~ocal point o~ the two ~ens group zoom len~. ' ' From equation (1) it can be calculated that: '',, X~-2~1-HH-delta+U- ~ (2~1+HH+delta-U)2-4~12~/2 ...(2) Fig. 13 illustrates the relation6hip bstween the ,', distance U o~ a sub~ect and the positional deviation (t) on a position detection element 4a, which ~orms a portion o~
the distance measurlng device which detects the distance of a sub~ect ~rom the ~ilm plane based upon the principle o~ '' 30 triangulation. ,'' , The tri~ngulation distance measuring device includes a ' , light emitter 3 having a light source 3a and a light ;emitting len5 3bt and a light receiver 4 having a light receivlng len~ 4b ~nd a position detection element 4a, e.g., a photo sen5itive detector (hereina~ter PSD). The rays o~
light emitted ~rom light source 3a are re~lected by the P5713SOl _ 25 --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 4a, 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 f, is given by the following equation:
t=Lxf/(U-f-d) ...(3), in which:
L represents the base length of the distance measuring device;
~ represents the focal length of the light receiving lens; `
and d represents the di~tance between film plane F and the focal plane of the light receiving lens.
The deviation (t) can be detected b~ the electric current, i.e., output, of position detecting sensor 4a in accord~nce with the quantity o~ light received by position detecting sensor 4a, in a well known fashion. The photographing optical system o~ the camera i~ ad~usted to ~orm an image on a ~ocal point o~ the image plane in accordance with the output signal, i.e., electric current, o~ position detecting sensor 4a, based upon equations (2) and (3), 90 that automatic ~ocusing can be e~ected. The actuating or driving mechanism o~ the photographic optical system is noted above.
It i9 necessary to shi~t the range o~ measurement o~
the ~ub~ect dlstance by the distance measuring device toward~ a close sùb~ect distance side in order to achieve the macro ~unctlon o~ the camera. In the macro mode, the photographing optical ~y~tem i~ elther partially or entirely di~placed, Prom a standard picture taking position, towards the sub~ect to be taken, as is well known.
In the embodiment o~ Fig. 12, the ~irst lens group o~
the photographing lens i5 moved ~orward, towards the sub~ect ov-r a predetermined di~placement, in the macro mode, . " ' ' .'.
..

132~7 `
P5713Sol independently of (and beyond) the displacement effected by the automatic focusing device during normal photography.
Fig. 14 represents one mechanism 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 of 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 o~ prism P aredr and n, respectively, the deviation tl o~ the image on position detecting sensor 4a, with respect to the sub~ect distance Ul, can be obtained as follows:
~irstly, the incident angle alpha o~ the rays of light on the plane o~ prism P ad~acent to the subject is determined by the ~ollowing equation:
alpha~tan~l ~L/(~ -d)} ~ c~
~e~raction angle beta o~ the rays o~ light which ar~
incident upon prlsm P having an apex angle ~ at the incident angle alpha is determined by the ~ollowing equation:
beta-alpha- S ~sin l tn sin ( S - sln (alpha/n))~, and, there~ore ~ ~~
Accordingly, deviation tl o~ the image on position detecting sensor 4a will be determined ~y tl-~ x tan ~ .
Sub~ect distance Um~l, which is obtained when light Whlch is coincident with the optical axi~ Or light receiving lens 4b intersects the optical axis o~ light emitting lens 3b is determined a~ ~ollows, provided that the thicknes~ Or pri5m P 18 negligible:
Um~ /tan ~sin l (n ~in ~ ) ~+~+d.
In one example, the present Applicants calculated the values o~ U, Ul, t, tl, and t-tl, in a camera in which the 7.,.,~ (r ' P5713S01 13298~7 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) equals 7.02mm; delta, i.e., the distance between the focal point of the first lens group and the focal point of the zoom lens, equals 8~.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 0.5502mm.; L, i.e., the base length of the distance measuring deyicej equals 30mm; f, i.e., the focal length of the light receiving lens, equals 20mm.; ~ , 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 bé measured eguals 0.973m- infinity; and the number of steps o~ ~orward feeding movement of the zoom lens is 18, so that the range of 0.973m - 6m iB divided into 17 forward feeding motion steps o~ the zoom lens. The results of these calculations are illu~trated in Table 1 hereinbelow. In these calculations, the distance range of 0.973m- 6m i9 shi~ted toWards the range o~ 0.580m- 1.020m.
In Table 1 hereinafter, step 17-18 represents a shi~ting point at which the 17th step changes to the 18th - step7 similarly, the step 0-1 represents a point of transfer between 0 and the ~irst step.

P5713S0l - 28 - 1 329~7 :~ :

POSITIONS OF IMAGES ON THE POSITION DETECTING SENSOR
AT DIFFERENT SUBJECT DISTANCES ~ :
STEP NO. U tm) U l~m) t(mm) _l(mmL _l-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 o.ssl 0.1500 0.17190.0219 ~ - -'5 3.310 o.sll 0.1827 0.20130.0186 14 2.814 o.s7s 0.2153 0.23050.0153 `
lo 13 2.450 0.841 0.2476 0.2sss0.0120 -~
12 2.172 0.810 0.2797 0.28840.0087 11 1.952 0.782 0.3115 0.31700.0055 ~ 10 1.775 0.756 0.3432 0.34550.0023 9 1.628 0.732 0.3747 0.3738-o.ooos 8 1.504 0.709 0.4059 0.4018-0.0041 7 1.399 0.688 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 3 1.100 0.616 0.5591 0.5396-0.0195 2 1.045 0.6Cl 0.58gl 0.5666-0.0225 1 0.996 0.587 0.6189 0.5934-Q.0255 o-~ o.973 0.580 0.6338 Q~Q~-0.~270 U m~l-1.28.3m . . .
As can be seen ~rom Table 1, an image deviatîon of 0.027mm occurs at the position detecting sensor 4a at the two extremities o~ the range o~ measurement o~ the sub~ect distance which can be mea6ured, as a result o~ compensation by prism P. Such a deviation corresponds substantially to about 1 step, ln the sense o~ the numbsr o~ reeding steps Or tho zoom len~. Accordlngly, it is not possible to move the photographic len~ into a correct ~ocal point by directly oontrolllng displacement o~ the photographing optical system in ro~ponse to the output o~ position detecting sensor 4a, 3J thu- rosultlng in an "out o~ ~ocus~' sltuation.
- In other words, it i~ impossible to complet~ly . .. .
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.. ~3 P5713Sol - 29 _ 1 32 98 87 ;

compensate for deviation in the images by using only prism P, since the rate of change of deviation tl o~ the image on position detecting sensor 4a with respect to s~bject 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 invent~rs have found that co~plete compensation of such deviation can be achieved if the rate of deviation tl is adjusted by multiplying this rate by 1.1130 (calculated by dividing O.S334 by 0.4794), which equals the change in t from step 0-1 to step 17-18 divided by the change in tl between step 0~
and step I7-lat since decreases in the deviations t and tl between steps 17-18 and 0-1 are 0.5334mm and 0.4794mm, 15 respectively. To this end, in the present invention, a ;
macro mode compensating optical element is adapted to be ~-selectlvely moved ln ~ront oS the distance measuring optlcal system only when the camera is placed in the macro mode, in order to optlcally extend the base length between the llght emitter and the light receiver o~ the distance measuring optical system, and in order to intersect the optical axls o~ the llght emitter and the optical axis o~ the light reeeiver with a rlnite distance. Further, in this embodiment, an actuatlng mechanism is provided ~or moving ~S ths macro compensating optical element ~n ~ront Or the light receiver in coor*ination with transfer or movement Or the photographing optical system, i.e., the zoom lens, ~rom the normal photographic mode to the macro mode, as discussed in detall herelna~ter.
Figure 9 illustrates an optlcal arrangement of the dlstAnce measuring device when in the macro mode, in the utomatie rOeu~ eamsra o~ the present invention. In this rigure, macro compensating element 4e comprises a prism 4c and a ma~X or ~rame 4d, rather than only the optieal wedge -~ 35 o~ Fig. 14. Element 4e 1g moved in ~ront Or light receiving .~ len~ 4b o~ the distance measuring device when the camera ~g .~ - , .
r. ~ . ,.
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1 3 ~ ~ 8 ~ 7 P5713SOl - 30 - ~
:'' in the macro setting. In the normal photographic mode, element 4e is retracted away from the optical axis of light receiving lens 4b.
Prior to discussing the mechanical structuré 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 ~nd to refract rays of light which enter the prism.
Figure 10 illustrates in.detail prism 4c, mask 4d, and light receiving lens 4b. Figure 11 is a front elevational view o~ Figurs 10; and both o~ these figures illustrate how mask or ~rame 4d i9 capable o~ intercepting rays of light out o~ the path o~ light approaching the prism. Mask 4d includes a ~ront opening 4~ which is shown in the form o~ a generally rectangular, elonyated slot, on the ~ront) side o~ the ~rame located most closely ad~acent to the sub~ect being photographed, and a rear opening 4g (see Fig. 10) on the side o~ the ~rame or mask most closely ad~acent to light receiving lens 4b. Opening 4~ is in the ~orm o~ a sli~
spaced ~rom optical axis O o~ light receiving lens 4b by a distance (l) which is measured on the opposits side of the ¦ 25 optical axis ~rom light emitting lens 3b. Rear opening 4g is al~o in the ~orm o~ a elongated slit, which is substantially located along the optical axis O o~ light ¦ receiving lens 4b.
When prism 4c, together with mask 4d, move in rront Or llght receiving lens 4b, i.e,, when the camera is in the macro mode, a rirst lens group o~ the photographic lens is ~od ~orwaxdly by a constant displacement, independently o~
the dl~placement o~ the lens whlch ls ~ed ~orwardly during the normal photographlc mode by the automatic ~ocusing 3 devlce. As be5t seen in Figs. 9 and 10, when prism 4c is located in ~ront o~ light receiving lens 4b, the range o~
~ ' ' ,~ ' , .' . ' ' ''',,'' '' 1329887 : ~
P5713Sol - 31 -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 (1) 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 ~ndex of prism 4c are ~ 1~ 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 o~ light on the plane of prism 4c which is adjacent to the subject i5 provided by the ~ollowing equation:
alphal=tan 1 {(L+l)/(U2-~-d)) + ~ 1 This equation indicates that the base length of the triangulation distance measuring device i~ extended ~rom L
: to ~L+l) by the insertion o~ prism 4c in ~ront of the light receiving lens 4b. The re~raction angle betal o~ light which is incident UpOII a prlsm having an angle ~ 1~ which light i5 incident upon the prism at an incident angle of alphal, i5 calculated in accordance with the ~ollowlng equation:
betal ~ alPhal- ~ l+sin -ltnsin ( ~ l-sin talphal/n))~, and, there~ore: ~ 1 ' alphal ~ ~ 1 ~ betal.
Accordingly, deviation t2 o~ the image on position detecting sensor 4a is equal to ~ x tan ~ 1~ i.e., t2 = F x tan ~ 1 The sUbject distance Um~2 which is obtained when light ~' 30 coincldent With the optical axls o~ light receiving lens 4b - inters~cta the optical axis o~ light emitting lens 3b is yielded by u~ing the ~ollowing equation, provided that the - thlcXne~ o~ prism 4C ig negligible:
~: Um~2~tL~l)/tan ~sin~l~n x sin C~ 1) +~td.
3STable 2 hereina~ter lllustrates the resUlts o~ the caloulations in which the dlstance measuring device o~ Figs.
, 1- ., . ..

1329~87 :
P:~713SOl - 32 - -lO and ll has been applied to a photographing lens satis~ying 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)~l, i.e., the focal length of the first group, eguals 24.68 mm;
(c) HH, i.e., the principal point distance, eguals 7.02mm;
(d) delta, i.e., the distance ~etween the ~ocal length o~ the ~irst lens group and the ~ocal length o~ the zoom lens, equals 30.04 mm; ~ ;
(e) d, i.e., the distance betwesn the film plane and the ~ocal plane o~ the light receiving lens, equals 6.292mm;
~) the displacement o~ the ~irst lens group in the macro setting equals 0.5502mm;
.:
~g) ~, i.e., the base length o~ the distance measuring device, equals 30mm~
~h) ~, i.e., the ~oca~ length o~ the .
- light receiving lens, eguals 20mm:
i.e., the angle Or prism 4c, eguals 3.39;
~) n, i . 8., the re~raction index Or the prism, equals 1.483;
~k) ~1), i.e., the distance representing the parallel dioplacement Or the rays o~ ;
light, eguals 3.39mm;
tl) the range o~ measurement Or the ~F 3~ dl~tanc~ o~ the ~ub~ect which can be ~ oa~ured eguals 0.973m ln~inity~
b, ~ (m) the number o~ oteps o~ ~orward ~ eeding movement o~ the zoom leno 1~ 18~
.-~
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P5713S01 - 33 - 132 ~ 8 8 1 : - ~

(n) the range of 0.973m- 6m is divided into 17 steps; and (o) the photographic range of 0.973m~ 6m is shifted lnto the range of 0.580m~
1.020m.

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P5713S01 - 34 - 13~9~87 POSITIONS OF IMAGES ON THE POSITION DETECTING SENSOR AT
DIFFERENT SUBJECT DISTANCES WITH THE MACRO COMPENSATION
ELEMENT OF FIGURES 9, 10 AND 11 STEP NO. U tm) U 2(m) t(mm) _2(mm) _2-t tmm) 17-18 6.000 1.020 0.1004 0.1005 0.0001 17 5.154 0.996 0.1170 0.1171 0.0001 16 4.027 0.951 0.1500 0.1500 0 -1015 3.310 0.911 0.1827 0.1827 0 14 2.814 0.875 0.2153 0.2152 -0.0001 13 2.~50 0.841 0.~476 0.2475 -0.0001 12 2.172 0.810 0.2797 0.2796 -0.0001 11 1.952 0.782 0.3115 0.3115 0 1510 1.775 0.756 0.3432 0.3432 0 9 1.628 0.732 0.3747 0.3746 -0.0001 ;
8 1.504 0.709 0.4059 0.4059 0 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 0 3 1.100 0.616 0.5591 0.5591 0 2 1.045 0.601 0.5891 0.5891 0 1 0.996 0.587 0.6189 0.6190 0.0001 250-1 0.973 0.580 0.6338 0.6338 0 U m~2-1.283m : :' .

It should be clearly understood ~rom Table 2 that the : .
deviation o~ the images on the position detecting sensor 4a at di~erent steps between the normal photographic mode and the macro mode will there~ore be wlthin +/- O.OOOlmm. This i9 represented by the value t2-t in the last column on page 2. Accordingly, it is possible to almost completely ~orm imag~s at the ~ocal point by ad~usting the photographic 3S optical systam in ac¢ordance with the output Or the position .
dotecting sensor 4a. Table 2 illustrates that prism 4c can ,.: ~, .

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1~2~7 P5713SOl - 35 -optically extend th~ base length, wnich is normally 30mm 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 wlll be 33.39mm when the camera is in its macxo mode; às 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 o~ the camera, ~y actuating previously discussed shutter unit 23 in accordance with the output signals, i.e., the measurement data, which are sent by position detecting sensor 4a. Specifically, when drivlng pu~ses are applied to .the pulse motor of shutter unit 23 in accordance ~ith the measurement data which has been received from detecting 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 ~rame 24 together with lt. As a result o~ this rotation of rront lens ~rame 24, the ~ront lens element group Ll ls moved along the direction o~ the photographing optical axls, vla the action o~ helicold 25, in order that ~ocusing o~ the photographlc lens assembly will be automatically e~ected.
Lens barrel block 1 rotates cam ring 14 when ~ooming motor 5 i9 driven. Rotation o~ ca~m ring 14 causss roller 17 o~ ~ront ~rame 16 to engage the extreme macro position ~ixing ~ection 20g Or cam groove 20, i.e., roller moves into section 20g rrom macro trans~er section 20~ o~ cam ring 14, so that ~ront lens element group Ll will be ~ed ~urther ~orwardly to move into position ~or macro mode operation o~
the camera.
A~ clearly seen in Figs. 1 and 2, macro compensating element 4e 19 5ecured to a ~ree end o~ a ~lexible comFensation or correctlng ~lag 42, which is pivoted at its base end to camera base plate 6 via a sha~t 41 located below llght recelver 4. Flag 42 i9 normally retained in a sUb~tantlally straight po~ition when no external ~orce is '~ "": ;,';;

: ' ,~ . . , . ~ .

132~87 P5713SOl - 36 -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 attached to s~aft 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 seen in Flg. 2 and (better) 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 o~ the distance measuring device and in front o~ light receiver 4 whenever the cam ring 14 rotates to the macro setting position. As shown in Fig. 1, a substantially semi-cylindrical recesC (or other recesscon~iguration) 44a is provided on the gear 15 ad~acent to the camming sur~ace or ~rojection 44. This recess is provided to ~acilitate the pivoting or rotating motion o~ ~lag pro;ection 43 as the cam ring rotates. In other words, recess 44a i9 necessary to ~acilitate turning movement o~ the projection and hen~e pivoting or rotating motion o~ optical element 4e into the position illustrated in dotted lines in Fig. 2, in front o~
llght receiver 4. Alternately, ring 14 or gear 15 can be ~ormed with a smaller diametsr in order to provide su~icient pivoting room ~or projection 43. Camming pro~ection 44, which e~ects, via its engagement with pro~ection 43, rotatlonal or advancing motion of macro compen~ating optical element 4e, is positioned and con~lgured 90 that the optical element will be rotated ~lightly past the posltion in which the element would be allgned with the optical axis o~ light receiver 4. However, 3~ the ~lat end o~ the element 4e which most closely approaches - ~upport plate 6e whlch is integrally attached to base 6, i5 ' '....
' .'.:., 132~8~7 P5713SOl - 37 -adapted to engage the left hand side surface of plate 6e (as seen in Fig. 2) via a shock absorbing nub or button 4g, 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 flexible flag 42, which 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 axi~ o~ the light receiver, into a position in ~ront of the light receiver, in order to optically extend the base length between the light emitter 3 and the light receiver 4.
C. Finder O~tical Svstem The ~inder optical system is best illustrated in Figures 1 and 15-20.
The Sinder optical system i~ designed not only to vary magnl~ication between a wide ~ield oS view with a small magnl~ication, and a narrow ~ield o~ view with a large magni~ication, in accordancs with the zooming operation o~
the photographing lens system, but also to provide a ~ield o~ view having less parallax when the camera is used in its macro mode.
One signi~icant Seature o~ the present invention is that the ~inder optical system is capable o~ automatically moving in association with both zooming o~ the photographic lens and movement oS the photographic lens into a macro ~otting in order to ~atisSy all o~ the reguirements oS a ~indor sy~t-m as set Sorth immediately above. While conventional Slnders appear to provide a plurallty oS bright ~- Sramo~ with diS~erent sizes in the ~ield o~ view oS the inder, this is not a satisSactory solution to the problems not-d abovo, e.g., the use o~ such Srames alone will not mlnimlz~ parallax in a macro operational mode such as that u~ed in the present camera.
'~
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P5713SOl - 38 - 132~8~7 Under such circumstances, and in accordance with the present invention, a finder optical device is provided 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 L3 and a mova~le negative lens in the form o~ a variable power lens L5, a second lens group having a negative lens L4-1 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 o~ the first lens group in order to refract rays o~ light towards the optical axls. The negative lens L5 o~ the ~irst group can be displaced from a position ad~acent to the sub~ect towards a positlon which is ad~acent to a photographer' B eye in order to vary the magni~ication ¦ 20 ~rom a wide ~ield o~ view having a small magni~ication to a ~arrow ~ield o~ view having a large magni~ication. Prism ' ~1, selectively brought into alignment with the optical axis o~ the ~inder optical system, serves to decrease the parallax when the photographic optlcal system is in the macro setting and when the negative lens LS o~ the ~irst group moves closest to the eye o~ the photographer along the optical axis.
The brlght ~rames which are illustrated in dashed lines in Flg. 52 de~ine the photographing ranges and are applied to the ~ace o~ the lens o~ the thlrd group which is closest to the sub~ect, i.e., on the le~t hand ~ace A o~ stationary ~y~pleco lens L4-2 in Figs. 15A, 16A, 17A, 18A, l9A and 20A, re~pectively. The~e yellow ~rame5, which ar~ placed on lens sur~ace A compri~e a central auto~ocus spot ~to be 3S po~itioned on the main portion o~ a photographic sub~ect), a large picture area ~rame ~for ordinary photography using the ' ' ' '', ':"
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P5713sol _ 39 _ 13298~7 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 L4-1 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 bright 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 ~f a semi-transmissive, semi-reflective concave mirror. Light rays emitted from (i.e., reflected by) the bright frames are re~lected rearwardly by concave surface R6 and are focus~d on the viewers eye. The eye recognize~ enlarged false images o~ the frames in a position in the far ~oreground, which images are ~ormed via the optical effect of lenses L4-1 and L4-2.
The negative lens L5 o~ the ~lrst group is movable, as noted above, so that it will move ~rom a position which it is located adjacent to the subject into a position in which it is more closely ad~acent to the eye o~ a photographer, in order to increase the ~ocal length o~ the photographic optical system during the normal zooming operation, so that magnification can be varied ~rom a wide field o~ view having a small magni~ication to a narrow ~ield of view having a large magni~ication. When a picture is taken in the macro ~bsyond tslsphoto) mode with a narrow rield o~ ViBW and large magni~ication, a prism is inssrted between the movable len~ ~5 and stationary lens L3 in order to decrsase parallax, so that light will ~e re~racted towards the location o~ the axis o~ the photographic optical system.
Enough room is provlded ~or the prism to plvot upwardly 1 3S ~o~ macro ~ocusing, i.e.~ thereby creating a nsed to move t~ lens L5 a relatively large dlstance, as shown in Figs.

' ''-'';" '' r-,,? (:
~ .
13298~7 16A, 17A, l9A and 20A, in order to insert the prism Pl therein in a pivotable or rotatable fashion.
On advantage of th, 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 having 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 adjustment. The two rear eyepiece lens groups L4-l and L4-2 which include the frames are fixed, and the curvatures of their respective surfaces are controlled so that the re~lected ~rames will have a desired magnification which is compatible with the image magnification over the entire range o~ zooming operation of the photographic lens.
The apex angle or angles o~ the selectively insertable prlsm ar~ de~ined by the resultant angles in the horizontal and vertical directions, in accordance with the positions Or the optical ~inder system and the photographic optical 6ystem. The prism can be a single wedge prism, or can be a double wedge shaped prism, as illustrated in Figs. 53A, 53B, and 53C, which illustrate a double wedge prism Plt which is advantageous because it is capa~le o~ bending light downwardly and rightwardly towards the optical axis of the photographic optical system.
As illustrated in Figs. 53, double wedge prism Pl has a sur~ace whlch inCreases, when viewed ~rom the top in the direction o~ arrow A ~see Figs. S3A and 53B) and which also increases ~rom the le~t hand to the right hand direction, as v~ewed rrOm the ~ront o~ the camera ~rom the photographing optlcal axis, and as shown by arrow B ~Figs. 53A and S3C).
In the example lllustrated, the angle ~ H can be 2.8, 3S the angle ~ V can be 4.2, the angle ,~ H' could be 4,2, and the angle ~ V' could be 5Ø
,: ', P5713Sol - 41 - 1 3 ~ 9 8 ~ 7 -. ` ~ -:

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 ~rames 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 picture taking mode. The viewing magnification or size of the bright frame images is also maintained constant throughout the zooming range of the photographic lens, as well as in the macro setting, due to the placement of the bright ~rames on the stationary lens element L4-2. The distance between the eye of a viewer and the image distance, i.e., the diopter o~ the ~inder, virtually does not vary, becau5e the zooming concave lens element moves over an image magni~ication o~ lx, or, i.e., is life size.
Parallax compensatlon in the macro or close up picture taking mode ls e~ected by posltioning the wedge prism between the lens elements~ as well as by the use o~ the compensation ~raming marks illustrated i~ ~ig. 52 (which is the normal means o~ parallax compensation in a close ~ocusing mode in view~lnder type cameras). The edges o~ the 2S wedge prism are tlnted green to hlghlight the frame that illustrates the photographic area in the macro or close-up mode.
Theoretically, the prism could be located in ~ront of the ~lrst lens group; however, by so arranglng the prism, it would increaso the over~ll slze o~ the ~inder optical ~y-t~m. The prism cannot, however, be located between the - ocond and third lens groups, because i~ it were inserted b-twoen these group~, the positions o~ the brlght ~rame and o~ th- virtual image o~ the sub~ect could vary in accordance 3~ With mov-ment o~ the prism. ~owev2r, when the prism is xetractably ins-rted between the positive lens and the ~, , ,"~ , ' ,. ' :,, 13~98~7 P5713SOl - 42 -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:
Exam~le 1 Figs. 15A, 15B, 16A, 16B and 17A, 17B illustrate different positions of a first embodiment of a finder device lo ~ormed in accordance with the present invention. Fig. 15A
illustrates the finder optical system when it is providing a wide ~ield o~ view with a small magnlrication; Fig; 16A
illustrates this finder system when it i~ providing a narrow ~ield o~ view wlth a large magni~ication; and Fig. 17A
illustrates the ~inder system whenever it is providing a narrow ~ield o~ view with large magnification and when it is in the macro mode, respectively. Figs. 15B, 16B and 17B, respectively, are views lllustrating the aberrations of the ~inder lens system in the positions o~ Figs. 15A, 16A and 17A, respectively.
This ~inder optical system includes a positive single lens L3 and a negative single lens 15 which ~orm the ~irst lens group, a negative single eyepiece lens L4-1 which ~orms the second lens group; and a positive single eyepiece lens ~4-2 ~orming the third lens group; together with a ~electively posltionable pri~m P1. Among all o~ these optical elements, only the negative single lens L5 is movable along the direction o~ the optical axis, and prism P1 is selectively movable into alignment wlth this optical 30 axi5 ~ all o~ the other lenses remain stationary.
Tables 3 and 4 which ~ollow illustrate the curvatures r, the distance~ d, the re~ractive indexes Nd and Abbe's number~ ~ d o~ the opposits side ~aces o~ optical elements T.3 ~ ~5, ~4~ 4-2, and Pl ~Table 4 only), respectively. As ~hown in the ~ollowing tables 3 and 4, each o~ ~eatures r, d, Nd and ~ d are designated by any one o~ numbers 1-8 and :

P5713Sol - 43 - 13~98~
..... ~ ,.. ..
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 magnification position (0.38x) and when it is in its narrow field of view, 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 surSace 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 surSace B of the negative single lens L4-1 oS the second lens group which is ;most closQly adjacent to the photographers eye is semi-transparent. As a result, a virtual image oS the bright ;20 rrame applied to Sace A oS the positive single lens L4-2 is ~ormed and reSlected by ~ace B, and is thereafter enlarged and viewed through the positive single lens L4-2, again as di8cussed previously.

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., ''' : ' P5713S01 - 44 - 13~3~7 ~ :

No. r d Nd ~_ 1 30.800 4.53 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 50.845 7.33 7 cx~ 2.23 1.60311 60.7 8 -11.780 .

15 ~O. E d ~ ~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 r 9 ~ CX~ 2.23 1.60311 60.7 as lO -11. 7~0 Exam~le Fig. 18A illustrates a second embodiment o~ the ~nder optical system in its wide rield o~ view, small magni~ication position; Fig. l9A illustrates this embodiment in ltg narrow ~ield Or view, large magni~ication position;
nd Flg. 20A illustrates this rinder optical assembly em~odiment in its narrow ~ield o~ view, large magnirication, m~cro mode ~osition; and Figs. 18B, l9B and 20B~
r-~pectively, illustrate the aberrations in the ~inder lens 3 8y~tem ln the three di~erent positions illustrated in Figs.
18A, l9A and 20A, respectively. In this second embodiment ~: . - ., .,~:, . .
. .
.
. - ~

f " `'' P5713Sol - 45 - 1 3 2 9 ~ ~ 7 ~ `

of the finder optical device, the lens system is different from that in the first embodiment as discussed in example 1, 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 de~ines the photographic range is again applied to ~ace A o~ the positive lens L4-2 o~ the third group, and ~ace B o~ the negative single lens L4-1 o~ the second group ls again semi-transparent, as in the ~irst embodiment o~ the ~inder system.

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P5713S01 - 46 - 1 3 2 ~

No. r d Nd ~d 1 25.800 4.50 1.49186 57.4 2 -190.341 0.50 (0.35x) ~
11.89 (0.648x) 3 85.200 1.50 1.49186 57.4 4 8.081 14.39 (0.35x) ~
3.00 (0.648x) -7.056 1.00 1.67003 47.3 6 34.700 5.37 7 C~O 2.93 1.60311 60.7 8 -12 .538 .. 0.30 9 -30. 259 2.23 l. 49186 57.4 -15.420 No. r d Nd ~: ~
1 25.800 4.50 1.49186 57.4 ~ -2 -190. 341 9.42 3 Cx~ 2.00 1.49186 57,4 4 CX~ 0.47 --85.200 1.50 1.49186 57.4 6 8.081 3.00 7 -7.056 1.00 1.67003. 47. 3 , 8 34.700 5.37 9 CX~ 2.93 1.60311 60.7 -12.538 0.30 11 -30.259 2.23 1.49186 57.4 12 -15.420 - As lllustrated in Fig. 17A, the ~inder optical device - - 30 o~ the present invention pre~erably satis~ies the ~ollswing conditions:
-~ ~1) 0.3 ~dP~0-5S
~2) rl+ ~1.8; and ~3) 0.45~ ~3/LD <0.7; wherein: ;
D ~ the total length o~ the ~inder;
35dP - the di~tanc- between the ~ace Or lens ~3 which ls mo~t clo~ely ad~acent to prlsm Pl and the ~ace Or lens L5 ~' :5, ''; ~ ., , ' , ' , ' , ' ~, "' "'' "
:~ , ' , '', ,. :', ,, !: ~ ' . , P5713~01 - 47 - 13~87 :.
which is mo.~t closely adjacent to p~ism 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 to m nimize the effective diameter of the prism when it is brought into alignment with the optical 10 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 ~imit, the effective diameter of the lens L3 will become large, making it difficult to provide a compact camera as does the present invention; to the contrary, if the value of dP was <0.3, it would become extremely di~ficult to smoothly and easily rotate prism Pl so that it would come into alignment with, and be capable o~ 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 <
~3/LD ~0.7, are provided to minimize the ef~ective diameter o~ prism Pl. The second criteria noted above is substantially equivalent to setting or establishing the ~ocal length FR o~ the lens system which is positioned .
rearwardiy o~ prism Pl when the prism is in alignment with the ~inder optical axis. Namely, if fl+ exceeds its noted upper limit o~ 1.8, the e~ective diameter o~ the prism will become large, thereby resulting in di~iculty in realizing a compact prism and ~inder.
Condition three is basically equivalent to a requirement ~or the third lens qroup located rearwardly o~
the prism. Namely, i~ ~3/LD is less than the lower llmit o~
- O.45, the tolerance o~ the system will become guite small.
~o the contrary, i~ the value o~ ~3/LD exceeds the upper 3g l~mit o~ 0.7, the e~ective diameter o~ the prism will increase.
. . ,~ .
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" ' '," ~.' 132~7 ` -: -P5713501 - 48 - .~.
. .
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 5 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 optical assembly 8 and strobe assembly 9 is best illustrated in Figs. 21-30. .
A mother plate 60 is attached to a f~nder bloc~ 54 which is mounted to base plate 6 via horizontal support plate extension 6b. The mother plate is provided with guide pins 62 integrally attached to the mother plate and which are adapted to Sit within a substantially linear guide groove 61 o~ cam plate 53. Sliding motion of cam plate 53 is in the lateral direction, with respect to the optical axis o~ the camera, and i9 restricted by the engagement between guide grooves 61 and guide pins 62; and a guide pro~ection or ~lange 60a ~shown in both Figs. 21 and 22) is ~ormed.integrally with mother plate 60 and serves to prevent cam plate 53 ~rom ~loating or moving away ~rom the ~ront sur~ace o~ the mother plate, particularly at the front end .- 25 o~ cam plate 53 where the ~lange engages the cam plate.
- Finder mother plate 60 includes a variable power lens guide groove 63, a de~lection prism guide groove 64, and a j gtrobe assembly guide groove 65. Each o~ these guide 3`- ` groov~s extends parallel to the photographic~ptical axis of tho cam~ra. A gulde ~ro~sction 66a Or variable ~lnder lens rame 66, which carries the variable ~inder power lens group 5, is ~ltted within variable power lens guide groove 63.
Guide pro~ction 67a o~ de~lection prlsm actuating plate 67 lidably positioned or ~itt~d within de~lectlon prism 3S: guid~ groove 64J and guide pro~ection 68a Or gtrobe assembly ca~o 68, which casing has a concave re~lector 59 attached :: . .
:~ `

~: , . .. . .
6 `'~ .',. ', ' ' 132~8g7 P5713Sol - 49 -thereto, is fitted or positioned within strobe guide groove 65.
Variable power lens frame 66, deflectlon prism actuating plate 67, and strobe assembly case 68, together move in a direction which is parallel wi~h respect to the optical axis, along the respective gui~e groov~.s. Guide projections 66a, 67a, and 68a are provided with driven pins 69, 70 and 71, which fit within the variable power cam groove 55j 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 compeneating cam groove 56, and strobe cam groove 57 correspond to sections of zooming cam grooves 20 and 21 o~ cam ring 14 which have been illustrated in Fig. 7 and described with respect thereto. Speci~ically, the variable power cam grooye 55 includes an extreme wide angle ~ixing section 55a, a variable power section 55b, and an extreme telephoto ~ixlng section 55c, with the angles 0 1~ 0 2 and 0 3, rsspectively, o~ 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 S6a, a pro~ecting movement section 56b, i.e., a forward ~eed section used ~or the macro mode, and a projected position ~ixing section 56c, i.e., an extreme macro ~ixing section.
Strobe cam groove 57 include~ an extreme wide angle ~ixing ~e¢tlon 57A~ a variable power section 57b, an extreme telephoto ~ixing ~ection S7c, a macro ~eeding section 57d, and an extreme macro ~ixing section 57e. The relationship botweon cam grooves 55, 56 and 57, and zooming cam grooves 20 and 21~ i~ best lllustrated in the schematic or plan view illUstrated in Fig. 44.
3S The variable power lens ~rame 66 which supports the vaxiable poweX lens group ~5 is movably supportsd along . ', .
': ' ' ''' "' .

1329~
P5713Sol - 50 -guide face 54a of flnder 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 vari~ble 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 ~inder.
The deflection prism actuating plate 67 is illustrated in Figs. 26-28, and is hereinafter described in greater detail.
15De~lection 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 8uppoxting pins include torsion springs 75 which surround them, with one end o~ each spring bearing against a ! 20 respective abutment 76 which abutments are provided along the side ~aces of deflection prism Pl, so that the de~lçction prism will be continuously biased into a position in which the prism P1 moves into alignment with the optical axis o~ ~inder lenses L3-L5. Abutment 76 are located in arc-shaped grooves 79 ~ormed in ~inder bloc~ 54, as best illustrated in Figs. 26-28. The de~lection prism actuating plate 67 is held between ~inder blocX 54 and a guide plate 80 ~see Fig. 25) connected to ~inder block 54 so that a - guido pin 81 which is positioned on the side ~ace o~ ~inder block 54 will ~it within linear guide groove 82 o~ guide plate 80.
Po8ition restrictlng abutments 76 on the prism can be engaged by a stop sur~ace 77 and a guiding sur~ace 78 o~
- de~lectlon prism actuating plate 67~ ~urther, the prism - 35 abutments 76 can come into contact with an end sur~ace o~
the groove 7~ in plate 67 ~see Fig. 27). De~lection prism .' ' ''','' '.,.;' .' .

, , . ' , ~ h ' 7 ~:
P5713Sol - 51 -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 it 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 o~ the ~inder will be de~lected downwardly by prism Pl, as illustrated by the arrow in Fig. 28. As a result o~ this movement, a subject which is otherwise located below the ~inder optical axis will come into the camera field of view, and parallax in the macro mode o~ the camera will be decreased. It i5 even rurther decreased, as noted above, when a double wedge prism (Fig. 53A) is used to deflect the ~inder optical axis downwardly and (rightwardly) towards the optical axis o~ the photographing optical system.
A guide block 85 is provided along the side face of strobe case 68 and is ~itted within a linear guide groove 84 which is parallel to the optical axis o~ the camera which i5 rormed in guide plate 80, as illustrated in Fig. 30.
Further, heighk ad~usting pins 86 ~see Figs. 23 and 29) are provided on the upper and lower races of stro~e case 68 and a~o adapted to prevent the strobe case rrom ralling downwardly. The strobe case 68 moves along strobe cam groove 57 when cam plate 53 moves in the lateral direction.
Variable power section 57b Or strobe cam groove 57 ls adapted to move xenon lamp 58 rearwardly, away ~rom Fresnel 3S lens L6. Raarward movement Or the xenon lamp 5a causes the illumination angle Or light emitted rrom Fresnel lens L6 to 132~g7 : '.. , P5713Sol - 52 - -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 57d, the illumination angle is increased, and the guide number is therefore su~stantially 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 barriers 31, (see Fig.8 ) which are located forwardly of the front lens element group Ll of the photographic (zooming) lens system, and which are closed with the assistance of rotational force which is produced when cam ring 14 rotates within retracting or storing cam section 20b (see Fig. 7) in 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 o~ ,~rame 22 via pivoted barrier elements 31. The barrier 20 elements are pivoted, via pins 32, in a substantially ~ ;
~ symmetrical ~ashion with respect to the photographic opening 1 22b o~ the ~ront lens group support ~rame 22.
Barriers 3~ are disposed in a symmetrically opposite po~ition wlth respect to each other and include respective i 25 barrier plate portions 31a which can be moved so as to 1 pro~ect into the path o~ the photographing optical axis, as i well as drivlng arm portions 31b which are positioned on the oppo~ito sides ol' the barriers ~rom the side on which barrier plate portions 3la are located. Driving arm :
30 portion~ 31b are generally attached to the inner ~ront i;~
~ur~ace o~ barrier assembly 30 by pins 33. Driving arm portion~ 3lh in¢lude plns 33 which are engaged by op-rational arms 34a o~ op~aning and closing springs 34, as ~hown in Fig~. 31 and 32. In other words, pins 33 are 3~ adapted to ~lids within, and/or be moved by, respective ~ I'ork-~haped end portions o~ the driving arms.
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13298~7 Opening and closing springs 34 are comprised, e.g., of molded synthetic resin and incl~de 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 ~rame 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 ~2b of the frame 22 remains in an open position.
Driving arms 34c come into engagement with opposed ~lange portions 36a o~ pin 36, which i9 movably ~itted in a - 15 radial direction within front lens group support frame 22.
As shown in Figs. 31 and 32, pin 36 i5 engaged by a free end o~ an operational lever 38 which is pivoted to front ~ecuring plate 13 via pin 37, through an operational aperture 39 o~ the front group lens support ~rame 22.
; 20 Although a pivotable actuating lever is~illustrated in the embodiments o~ Figs. 31-34, any structure which can move pin 36 inwardly in a radial direction would be satis~actory.
Pln 36 occupies a substantially radially pro;ecting position, under the in~luence o~ the spring ~orce o~ sprlng 34, when no external ~orce is applied to pin 36, as is illustrated in Fig. 31. In this position, the barrier plate portions 31a are located away ~rom the photographing optical axl~ or path, and aperture 22b remains in an open position.
A re8tricting pro~ection or abutment 40 is provided on th- inner wall o~ cam ring 14, which is adapted to bear again~t the outer snd o~ the operational lever (or other - analogous structur~) 38 when the cam ring rotates in its ~lxed axial position into a predetermined position in order to pr09~ pin 36 radially inwardly; thig occurs when cam ring 14 ~pin 17~ rotates within the opening and closing section 20a o~ zooming cam groove 20.
,,,i", ~,j ' . .
.

1329~87 P5713Sol - 54 -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 en~age 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 o~ the lens system. As a result, the photographio openi~g 22b will be closed 80 as to protect ~ront lens element group Ll. Namely, ~ront lens groups support ~rame 22 closes barriers 31 a~ter the frame has been collapsed ~rom the rearmost position ~rom which a picture can be taken.
When a picture is to be taken, zooming motor 5 is reversed so as to rotat~ cam ring 14, so that the zooming cam groove 20 will be rotated ~rom a position in which opening and closing section 20a is engaged by roller~s) 17 towards a position in which lens collapsible section 20b is 80 engaged. ~his causes barriers 31 to open and the ~ront ~ lens group ~1 is moved into a position in which a picture ;' 30 can be ta~en.
Figs. 33 and 34 illustrate a second embodiment Or a mechanism used in a lens shutter type o~ camera in 1~ accordance with the present invention . As shown in Figs. 33 I and 34, thi~ barrier mechanlsm 30 i~ baslcally identical to 3~ tho embodiment illu~trated in Figs. 31 and 32.
~- Specl~lcally, barrier mechanism 30 in Figs. 33 and 34 also j ~ , .. . ,,.: ..

P5713SOl - 55 - 13l?98g7 include a pair of barriers 31, 31 which are positioned in a substantially symmetrical fashion with respect to the photographic opening 22b of front lens group support frame 22. sarrierS 31, 31 are pivoted to frame 22 via pins 32 in 5 order to open and close photographic openlng 22b. However, 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 symmetrically disposed with respect to each other and include l:arrier plate portions 3la 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 31a; and the barriers are pivotably attached 15 to the ~rame by pins 32.
Driving arm~ 31b include operational pins 133 which are engaged to, and which are adapted to abut or contact, a single wire spring 134 having elastic leg portions 134a. A
~ree end o~ each o~ the elastic leg portions 134a is adapted 20 to contact a respective pin 133 in order that barrier plate portions 3la will be continuously biased into an open position in which the photographic aperture 22b is opened and the barriers located away Irom the optical axis and the aperture. Thus, when no external ~orce is applied to 25 barriers, they constantly maintain the photographing ap~rture in an open condition.
Wire spring 134 is made ~rom metal and has a central, U-shaped portion 134b which bears against a support pin 135 provlded on ~ront lens group support ~rame 22. Wire spring 30 134 has a constant ~pring ~orce which ~orce will not ~ary in accordance with changes in temperature, humidity or other environmental parameters. Accordingly, it is there~ore po~ible to bias barrlers 31 ln a direction in which a photographing aperture i~ ~aintalned in an open position by 35 a JUbstantially constant spring ~orce.
' Operational pins 133 ara engaged by respective driving ' '':' '.
.

1 ~ 2 ~ ~ ~ 7 ~ -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 ~1, 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 loc~ted away from the outer side of each pin against which one elastic leg portion 134a bears. Driving arms 136 are pivoted to lens support ~rame 22 via pins 137. Driving 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 o~ pin 138, which is radially movably fitted within an opening 39 in frame 22. Pin 138 includes a head ~unre~erenced) which is adapted to bear against the free end Or operational lever 141: the lever i5 pivoted to ~ront seoùring plate 13 by pin 140, and the head can extend, when depressed, through an opening 39 o~ ~rame 22. The opening and closing pin 138 is normally maintained in a position in wh~ch it pr~jects outwardly ~rom the inner periphery Or rrame 22, and is radially movable by lever 141 into a position in which the head Or pin 138 is forced inwardly through opening 39, overcoming the inrluence o~ wire spring 134. Thus when an external ~orce is applied to pin 138, it moves radially inwardly against the ~orce Or spring 134, as ~oen in Fig. 34.
A8 in the rlrst embodiment, the cam ring 14 can be provlded, along its inner wall, with a narrowing pro~eation 40 attached to it5 lntsrior peripheral sur~ac~ which is adapted to pu~h tho operational lever 141 inwardly so that it will engage oporational arm portions 136b (via pin rlang-~ 138a) whon cam ring 14 rotates so that roller 17 is ~- po-itionod within oponlng and closing ~ection 20a Or zooming 3~ cam groove 20. Other 5uitabl~ actuating structure could algo be u5~d.

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1329~7 . ~
P~713S01 - 57 - ~
. :.
With such an arrangement 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 o~ 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 o~ actuating cam ring 14 effected by zooming motor 5), projection 40 will push the opening and closing pin 138 .
in a radially inward d~rection, via operational lever 141, in order to rotate barriers 31, via driving arms 136 and operational pins 133, so that barrier plate portions 3la 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 ~ront lens element group Ll. Namely, a~ter ~ront lens group support ~rame 22 i9 collapsed ~rom ths 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 plcture is taXen, zooming motor 5 will bs reversed to rotate cam ring 14 ~rom a position in which openlng and closing ssction 20a is engaged by roller 17 to a position in which lens collapsible section 20b is 80 ongaged, in order to open barriers 31, so that the ~ront lens element group Ll will move into a position in which a picture can be taken.
F. i~h~ Interce~tion AssemblY and Mechanism Th- light interception mechanisms are best illustrated in Fig-. 6 and 3S-38 o~ the present application.
~ In a lens ~hutter type o~ camera as described hereln, the ~ront and rear len~ eloment groups can be independently moved along the photographing optical axis direction in 3S ordex to e~ct a lens zooming op~ration. Since a gap exi9t9 between the ~ront lens group ~rame 16 and the rear ' . ' "- ' 1 ., :,, .

P5713S01 - ~8 - 1 3 2 9 8 ~ ~ :

lens group frame 18, and since cam ring 14, which includes through cam grooves 20 and 21 for actuating movement of lens frames 16 and 18, 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 group frames and through the cam grooves 20 and 21. Further, since front lens group frame 22 moves through opening 201 of frbnt cover 200 (see Fig. 6), rays o~
light can also enter the camera via opening 201. The front cover 200 covers the front face of lens barrel block 1 a'nd supports lenses L3 and L6 of the finder as well as strobe block 2. Opening 201 is formed along and defined by an inner ~lange 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 i5 in its zooming operation. An annular space 203 having a relatively small width W is provided between inner ~lange 202 and ~ront stationary plate 13. The front stationary plate is substantially annular in con~iguration.
In order to prevent rays o~ light ~rom penetrating into the camera, as noted above, a light intercepting mechan~sm has been provided. SpeciSically, a light intercepting assembl~ 210 which comprises a plurality o~ sections is provlded about the outer periphery o~ cam ring 14 and is adapted to cover through or continuous cam grooves 20 and 21 in order to intercept rays o~ light and prevent them ~rom enterlng the interior o~ lens barrel block 1. In the embodiment illustrated in Fig. 35, intercepting assembly 210 comprlses a gear ring 15, a ~lexible code plate 90 which is ad~acent to gear member lS along one side o~ the gear member, and a llght lntercepting tape 211 which extends on the opposite gide o~ the gear member 15. In other words, the annular gear membar is located between the ~lexible code 3~ plate 90 which ls wrapped about lens barrel block 1 over cam grooves 20 and 21, and the light tape 211, which is also ' ',..': ' .. ,:

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P5713Sol - 59 - 132~87 ~

flexible and which is wrapped about the lens barrel block so that it covers cam grooves 20 and 21.
Code plate so 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 ~hanging ~ocal length o~ the zoom lens, the extreme wide angle position o~ the zoom lens, the extreme telephoto position of the zoom lens, the collapsed position of the zoom lens, the extreme macro position of the zoom lens, e.g., in order to e~ect a variety o~ controls which are disclosed in detai~
hereinafter with respect to the mechanism for detecting the position o~ the zoom lens and for deciphering information relating to the position of the zoom lens.
Code plate 90 is formed ~rom a ~lexible material ha~ing a light intercepting property. Intercepting tape 211 comprises a ~lexlble material also having such a property, e.g., a dull-~inish blac~ paper. The code plate and the interceptlng (paper) tape are applied to the cylindriaal outer sur~ace o~ cam ring 14, along opposite sides o~ gear member 15, in order to cover the ma~or portions of zooming cam groaves 20 and 21. Gear lS is pre~erably superimposed or overlapped over the side edges o~ the code plate and the intercepting tape in order to ensur2 the interception o~
rays o~ light, as illustrated in Fig. 6.
An annular light intercepting member 220 which ~orms an additional portion o~ the light intercepting assembly is provided in annular space 203, which ls de~ined by the space between ~ront stationary plate 13, which rotatably supports the ~ront portion o~ cam ring 14, and ~ront cover 200, as best seen ln Flg. 6.
Annular light intercepting member 220 which is positioned within annular space 203 comprises an elastlc annular body 221, e.g., rubber, and an annular rein~orcing plate 222, so that the llght intercepting member 220 will be have the overall con~iguration o~ a substantlally ~lat .; .....

1 3 2 ~ ~ 8 7 annular ring, as best illustrated in Figs. 36 and 37. Thethickness w of light intercepting member 220 is slightly less than the width ~ 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 ~eriphery of decorat~ve frame 220.
Rein~orcing plate 222 can be secured to elastic body 221, e.g., by partially lmbedding the elastic body 221 into connecting recesses, holes or apertures 224 formed in reinforcing plate 222, which plate is made, e.g., of metal or synthetic resin. The inner lip 223 i5 extremely flexible and is capable o~ moving in either direction axially o~ a lens barrier block about which it is positioned. The lip can thus play a minor role in reducing rebound o~ the barrier block a~ter it ce~ses movement in a ~irst axial direction.
Fig. 38 illustrates a second embodiment o~ the annular ring illustrated in Figs. 36 and 37, in which two spaaed light intercepting lips 223 ~rather than merely one) are ~ormed on the ihner periphery o~ annular light intercepting member 220 in order to increase the light interception e~eat o~ the apparatus. These lips are spaced rrOm each other ln a parallel ~ashion and ~orm a generally annular U-~haped, inwardly directed annular rlange for the light intercepting member. Elastic body 221 is used to cover the outor periphery o~ rein~orcing plate 222 ln such structure.
Alternately, lt would be possible to replace annular llght intercspting member 220 with a conventional O-ring structure, which would be the slmplest manner o~
intercepting light and preventing it ~rom reaching undesired areas within the camera.
With such a light intercepting mechanism, undesirable ,", ' ' '.

132~8~7 P5713Sol - 61 -light rays will not enter the camera lens system through the circumference o~ 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 a~e 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 o~ ~ront 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 o~ the distance measuring device, i.e., the range ~inder, and, e.g., tha exposure control device on the camera body, a ~lexible printçd circuit board (hereinafter re~erred to as an FPC board) is desirably used. The mechanism ~or gulding movement o~ the FPC board and the anti-re~lection assembly which are used in conjunction with such board are described hereinbelow in detail with more specific re~erence to Figs. 39-43.
FPC board 160 (see Figs. ~9 and 40) provides operational signals to shutter block 23 ~rom one side of the camera body. This board is made ~rom a ~lexible synthetic re5in sheet having a predetermined printed circuit pattern thereon; in general, such FPC boards are well known.
Aa lllustrated in Fig. 39, FPC board 160 has a connecting pattexn 161 at a ~ront end oi~ the board to which ~hutter block 23 can be electrically connected, and a rear connecting pattern 162 to which a CPU ~a central processing unit whlch is not illustrated in the drawings) which is provided in the camera body can be electrically connected.
FPC board guide plate 163, whlch guides FPC board 160, is ' :.
. . .
., . .. : , 1329~7 -P5713Sol - 62 -.. . .
secured to the camera body at ~ base or rear portion thereof, and extends into a space between cam ring 14 and decorative frame 22, forwardly of lens b~rrel block l.
Securing clips 166 are provided for attaching thé FPC board 163 to the guide plate, and clamping members 167 (see Fig.
41) are provided for attachin~ the ~PC board to the front portion of a camera body frame, e.g., which is die cast, or to the rear portion of a lens barrel frame(base 6).
A bent guide 165 is provided on the front end of F~C
board 163; this bent guide comprises a pair of front and rear guide pins 168 and 169. These guide pirls are pre~erably 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 ~reely bent ~orwardly 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 o~ the movement of shutter block 23 ~orwardly and rsarwardly in an axial direction.
Accordingly, guide pins 168 and 169 are pre~erably immovable pins which are not rotatable. Alternately, it is possible to replace these pins with guide rods or sha~ts over which the FPC board will be bent in opposite directions.
A5 ~hutter block 23 moves ~orwardly and rearwardly, the movable bent portion 160b o~ the FPC board also moves forwardly and rearwardly. Although the extension o~ the FPC
board 160 extend5 rearwardly ~rom the board guide plate 163, ag shown in Figs. 39 and 40, actually the rear extension o~
t5 FPC board 160 can be ~ent forwardly along, and by, a bent guide 170 of guide plate 163 in order to move the board 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 tnat rays of light which are incident upon the lens system will be reflected by FPC 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-re~lection means on the FPC board 160. As one solution, FPC board 160 can be formed from a dull-~inish, black synthetic resin material. Alternately, the FPC board 160 can be provided along its inner sur~ace, i.e., on its sur~ace which i5 adjacent to the optical axis o~ the camera, with an anti-re~lection sheet 171, as illustrated in Fig.
43. Such a sheet can comprise, e.g., a dull-~inish black paper or the like, and is adapted to be placed on the FPC
board 160. Pre~erably, the anti-re~lection sheet 171 is simply loosely superimposed on the FPC board without being adhered to the board in order to provide ~lexibility against de~ormation due to expansion and shrinkage o~ the material.
Sheet 171 lle~ on the FPC board in the area between bent as portions 160a and 160b o~ FPC board 160. A third solution i5 to coat at least the inner sur~ace o~ FPC board 160 with an anti-re~lective layer.
With the guide mechanism Or the FPC board and with the anti-re~lection mechanism which are noted above, when the ` 30 zooming motor 5 is driven to rotate in order to rotate cam : : ring 14, rrOnt len~ group ~rame 16 and rear lens group ~rame 18 Will be moved in directions along the optical axis in accordance with the cam grooves 20 and 21 on cam ring 14 in ord-r to e~ect a zooming operation, and can be moved into a ~;
po~ition in which the camera is in its macro setting or mod-. Movement o~ the rrOnt lens group ~rame 16 causes ~- , . . .
" , , ' .

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i32~7 `P5713S01 - 64 -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.
Specifically, FPC board 160 is integrall~ 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 o~
the FPC board is guided by FPC guide plate 163. The immovable bent portion 160a of the FPC board 160 ~is 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 o~ shutter bloc~ 23, only the movable bent board portion 160b will be displaced forwardly and rearwardly in order to absorb the movement o~ shutter bloc~ 23, as illustrated in Figs. 40 and 42. In this fashion, ~PC board 160 can be surely guided within the annular space 164 located between cam ring 14 and decorative ~rame 22 (Fig 41).
Since the FPC board 160 has an anti-re~lection ~tructure as disclosed above, internal re~lections which would otherwise cause an undesirable phenomena, e.g., a ~lare or a ghost, will not occur.
H. ~etection Mechanism ~ox Detectina In~ormation Relatinq to the ~ositlon o~ the ~oom ~ens A~ noted previously, in a lens shutter camera ~ormed in accordance with the present invention, the photographic optical system is moved along the optical axis by the rotation o~ cam ring 14, so that the rocal length o~ the photographic optical system will vary, and so that the optical system will move ~rom one extreme angular position o~ the cam ring into the macro setting position, and ~rom the other extreme angular positlon o~ the cam ring into a lens ~totally~ collapsed position. In such a lens shutter 33 type o~ camera, which includes a zoom lens, it is necessary, e.g., to detoct the ~ocal length o~' the photographic optical ' ~

132~
P5713SOl - 65 -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 posit~ons of th zoom lens, can easily be detected by code signals on the single ~lexible code plate so which is provided on cam lo ring 14. Speci~ically, code plate so, 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 ~lattened condition, in which the upper half of the drawing illustrates the cam pro~iles o~ zooming cam groove 20 and 21 o~ cam ring 14, and cam grooves 55, 56 and 57 o~ cam plate 53, respectively. Brush 92 includes a common terminal C and lndependent (bristles) terminals T0, Tl, T2, and T3. When each o~ terminals T0-T3 is electrically connected to the conduptive lands 93 o~ code plate 90, a signal "0" is issued, and when each o~ the terminals T0-T3 are not electrically connected to conductive lands 93, a signal "1"
is issued. The angular position o~ cam ring 14 can be detected by the combination o~ signals "0" and "1". A
plurality o~ dummy terminals 94 are ~ormed in conductive lands 93. The purpose o~ the dummy terminals, which are ~ormed ~rom the same material as conductive lands 93, is that the ~lexible code plate bent about the cam ring, and in order to improve the physical strength o~ the plate and ~till provlde an area wlthout electrical contact the dummy termlnal~ were so positioned to increase ~lexibility while preservlng ~trength. Additionally, these dummy terminals provide (non-conductive) lands upon which the terminals ~0-13298~
P5713SOl - 66 -T3 of the brush can ride as the cam ring is rotatPd.
The four bit information re~eived from terminals TO-T3 are provided as zoom code data zPo, ZPl, ZP2, and ZP3, respectively, of a zoom code encoder, as is clearly illustrated in Fig. 45. This figure comprises a table of combinations of signals "O" and "1", in which the angular position, i.e., POS, of cam ring 14 is divided into 13 steps between "O" and "9", and "A", "B", and "c", respectively, which are hexadecimal numbers.- The number "O" designates a locXed position, and the "C" position designates a position in which the camera is in its macro mode. Between the locked position and the macro position, there are nine focal length positions ~0-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 o~ cam ring 14 is controlled by the mode ¢hanging eiwitch 101 and the zoom switch 102, which are illustrated in Figs. 47-50, in accordance with positional in~ormation o~ cam ring 14 as determined by code plate 90.
~ he arrangement o~ 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 sur~ace 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 release switch into an ON position ~neither o~ these two switches are shown in the drawings, however).
Mode changing swltch 101 ls a trans~er switch which can occupy 3 posltions, l.e., a lock position ~LOCg), a zooming posltlon ~l.e., ZOOM), and a macro position, i.e. ~MAC~O).
A~ l}lustrated in Figs. 49-50, when macro button 101a is not depre5sed, switch lever 101b can move bet.ween the LOCK and ZOOM po5itions. When macro button 101a is depreSsed~
however, and when switch lever lOlb slides onto the upper '. .
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P5713Sol - 67 -surface of macro ~utton lOla, the macro mode of the camera will be set. Figs. 49 and 50 are cross-sections of the macro and zoom-lock switches, respectively. When in the LOCK position, neither the releasing operation nor the zooming operation of the zoom 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 zoo~ing operation cannot be effected.
Fig. 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. ~
Zoom 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 ~e 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 ~orward and reverse directions by switching the position o~ zoom switch 102 between the WIDE and TELE positions.
Mods changing switch 101 and zoom switch 102 actuate the camera o~ the present invention as detailed hereina~ter.
In actual use, positional in~ormation relating to the position o~ cam ring 14 which is indicated by code plate 90 will be used.
1. For the LOCK position of the mode changing æwitch 101, zooming motor 5 is reversed to rotate cam ring 14.
When the angular position POS o~ cam ring 14 becomes ~'0~
(see Flgs. 44 and 45) as detected by code plate 90 and brush 9~ zoomin~ motor 5 Will stop rotating.
2. For the MAC~O position o~ the mode changing switch 101, zooming motor 5 rotates in the ~orward directlon and 8top~ rotating when POS reaches the ~'C~ position.

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13~98~7 P5713Sol - 68 - ~
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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 rotat~s in the forward direction 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 o~ time after POS reaches the "1" position. After 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 ~osition, and will stop after it rotates in the ~orward direction for a predetermined short period o~ time when it is in the WIDE position, respectively.
De~ails o~ several o~ the positions will now be described.
POS l: Since the code signals change at the LOCX
posltion and at the extreme WIDE position, these extreme positlons are detected. More precisely speakinq, the LOC~
position is not "POS 0", but is instead a point which is located b~tween POS O and POS 1. However, when the camera is in the LOCK position, the brush ls in POS 0, ln a location very close to POS l. Similarly, the WIDE extreme ~05ition is apoint between POS l and POS 2. However, when th~ camera is in the extreme WIDE position, (which is not a -~; 30 ~wlde 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 ~rom the eXtreme WIDE position to the LOCK
: ~ ~ pooltlon, and vloe ver~a.
POS ~7': ~hls zone i~ provided ~or absorblng the - 3~ ~baaklagh o~ cam ring 14 (ie., backlash ~rom moVement Or the ~ ns 9yst-m). Sp~ci~lcally, a5 illustrated in Flg. 45, --:
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2~7 P5713SOl - 69 -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 a~ 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 e~posure), 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 ~ed at the TELE zone and the TELE extreme positions. This is the reason that POS 9 ls represented by f7 and POS A is represented by f7' in order to distinguish it from f7. The zone ~7' is quite small, and accordingly the zone f7' can essentially be considered identical to the extreme TELE
positlon.
POS B: In a rashion similar to POS 1, thls zone is provided to distinguish the extreme MACRO and TELE
positions. Unlike POS 1, in which the WIDE extreme position i5 a changing point between POS 1 and the WIDE extreme position, and POS B is an extreme TELE position representing changing points between POS 9 and POS A, respectively.
POS 2 - POS A: These are intermediate ~ocal length positions which comprise a plurality, e.g., 9 in the illustrated embodiment, steps.
The CPU then checks the code in~ormation and the 80tting po8ition~ ~or the various switches when they are turned into their ON positions. I~ the mode changing switch i~ in zoom po8itlon, no zooming will be necessary when the 35 cnm ring is in any position between and including POS 2 and POS A. I~, however, the mode changing switch is in a . ~ ,.. . ..
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.i~ ~ ~
1~293~7 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 léns 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 zooming 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 o~ 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 ~rom 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 modi~ied without departing ~rom the spirit and scope o~ the claimed invention.

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Claims (20)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A light blocking mechanism used in a lens shutter camera including a rotatable cam ring with at least one camming groove therein, said mechanism comprising at least one light intercepting member positioned about the periphery of said cam ring, said member thereby comprising means for covering each said camming groove and for preventing light from entering the interior of said cam ring.

2. A light blocking mechanism in accordance with claim 1, wherein a photographing lens is positioned within the interior of said cam ring.

3. A light blocking mechanism in accordance with claim 1, wherein said mechanism further comprises a flexible code plate wrapped about one peripheral portion of said cam ring, a light intercepting tape positioned about a second peripheral portion of said cam ring, and an annular gear positioned about a third peripheral portion of said cam ring.

4. A light blocking mechanism in accordance with claim 3, wherein said gear is positioned between said code plate and said intercepting tape.

5. A light blocking mechanism in accordance with claim 3, wherein said cam ring includes a plurality of grooves.

6. A light blocking mechanism in accordance with claim 1, said light-intercepting member being independent of, and positioned about, said cam ring.

7. A light blocking mechanism in accordance with claim 6, wherein said light-intercepting member comprises a flexible code plate.

8. In a lens shutter type of camera having a cam ring mounted to a support member to be rotatable at a constant axial position, at least one movable lens barrel movable along an optical axis of a photographic optical system of said camera in association with rotation of said cam ring, a light interception member positioned in a space between a front end of said cam ring support member and a front cover having an opening through which said lens barrel is adapted to move.

9. A camera in accordance with claim 8, wherein said light interception member is annular, and wherein said space within which said annular member is positioned is also annular.

10. A camera in accordance with claim 9, wherein the interior periphery of said light interception member comprises a flexible lip which slidably contacts the outer periphery of said lens barrel.

11. A camera in accordance with claim 10, wherein said flexible lip comprises means for minimizing rebound of said barrel.

12. A camera in accordance with claim 9, wherein an annular reinforcing plate is positioned about the outer periphery of said annular light interception member, said plate comprising metal or plastic which is more rigid than said annular member, said annular member being elastic.

13. A camera in accordance with claim 9, wherein said annular light interception member comprises an O-ring.

14. In a lens shutter camera having a lens comprising a lens barrel movable along the optical axis of the lens, and an annular member rotatable about said lens barrel, such that rotation of said annular member is operative to move said lens barrel along the optical axis to change an operational parameter of said lens, means for minimizing rebound of said lens barrel with respect to said annular member and means for preventing light from entering into a space between said barrel and said annular member.

15. A camera in accordance with claim 14, wherein said rebound minimizing means and said light preventing means comprise a ring member positioned within an annular space between said barrel and said annular member.

16. A camera in accordance with claim 15, wherein said ring member is secured to move with said annular member.

17. A camera in accordance with claim 15, wherein said ring member includes a flexible lip which slidably contacts the outer periphery of said lens barrel.

18. A camera in accordance with claim 15, wherein said flexible lip comprises means for minimizing rebound of said barrel.

19. A camera in accordance with claim 15, wherein an annular reinforcing plate is positioned about the outer periphery of said ring, said plate comprising a material which is more rigid than said ring, said ring being elastic.

20. A camera in accordance with claim 15, wherein said ring member comprises an O-ring.