JP3032312B2 - Imaging equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to relates to a photographing apparatus using the imaging device, the variable focus imaging optical system in Japanese.

[0002]

2. Description of the Related Art Conventionally, a photographing apparatus having a variable focus photographing optical system such as a zoom lens has a first group lens 1 for performing a focusing operation, as shown in a perspective view of FIG.
6 and a zoom lens unit 17 including second and third lens groups for performing zooming,
21 or driven in the optical axis L direction by a single motor,
It is configured to form an image on the imaging unit 18 such as a CD or a film. At this time, the unit 17 is moved from the zoom lens.
To drive a variable focus photographing optical system (hereinafter, simply referred to as a “photographing optical system”) provided in the camera and an external observation optical system 19 (hereinafter, referred to as a “finder”). A method of continuously moving the photographing optical system and the finder 19 in conjunction with each other using the cam 17b is known.

FIG. 6 is a perspective view of another conventional example, in which a first group lens 22 is fixed to a base plate 27,
The zoom operation is performed by the group lens 23 and the third group lens 24,
In the case of a rear focus lens in which a focusing operation is performed by the lens group 24, the imaging unit 18 and a drive unit 29 for driving the third group lens 24 are fixed to the base plate 27.
The plate cam 28 is moved to a plane orthogonal to the optical axis L via each pair of elongated holes and the pins 30 by the driving force from the drive motor 9. The magnification of the observation optical system (finder) 19 is changed by the cams 30a and 30b provided on the plate cam 28, and the lenses 23 and 24 of the second and third groups of the photographing optical system are continuously observed by the observation optical system. A method is known in which the system 19 is moved in accordance with the zooming amount, and the focusing operation is performed by independently moving the third lens unit 24 by a predetermined moving amount by a mechanism such as a helicoid (not shown). ing.

[0004]

However, in the method shown in FIG. 5 of the related art, the first lens group 16 for performing the focusing operation is apt to be large in view of optical design. There is a problem that the structural space of the lenses 23 and 24 of the second and third groups to be performed is limited, the load of the motor 20 for driving the first group 16 increases, and the power consumption increases. .

In the case of the rear focus lens system shown in FIG. 6, the size of the third lens unit 24 for performing the focusing operation can be reduced. Third lens group 2 corresponding to operation
Since the feeding amount of the fourth lens changes, the photographing optical system which may be set to an infinite number of focal lengths detects the number of focal lengths with high accuracy, and responds accordingly to the third lens group. It is necessary to automatically drive the lens 24 to a predetermined position. Therefore, there has been a problem that the focal length detecting means has a higher precision and a focusing operation control system of the third lens group 24 is complicated.

It is an object of the present invention to change the angle of view of a photographing optical system.
Easy and accurate, and for changing the viewfinder angle of view
The aim is to provide a shooting device that does not cause discomfort.
You.

[0007]

SUMMARY OF THE INVENTION Therefore, the present invention
The imaging device according to any of the following items (1) to (5)
Attempt to achieve the above objectives by providing
Things. (1) A photographing optical system that changes the photographing angle of view in stages, and the change
Determination to determine the state of the shooting angle of view of the shooting optical system to be performed
Means for instructing an operation of changing a shooting angle of view of the shooting optical system.
In response to the instruction to start changing the angle of view
To start changing the shooting angle of view of the shooting optical system.
A view angle change end instruction operation of the view angle change instruction operation means;
, The shooting optical system changes the shooting angle of view in steps
To finish the current stage.
The photographing angle of view of the photographing optical system until the decision means makes a decision.
After continuing the change operation, change the shooting angle of view of the shooting optical system.
Drive control means for stopping the operation;
The viewfinder angle of view is continuously changed in synchronization with the shadow angle change operation.
Operation of the finder device to be changed and the shooting start instruction operation means
The optical system stops changing the angle of view in response to
Focus adjustment operation of the shooting optical system according to the shooting angle of view
Photographing apparatus comprising:
Place. (2) The photographing optical system changes the photographing angle of view stepwise.
(1) characterized by having cam means for
On-board photography device. (3) The photographing optical system is different from the region in which the photographing angle of view is changed.
The preceding paragraph, characterized by having alternately unchangeable areas
The imaging device according to (1). (4) moving by the motor and the driving force of the motor,
The angle of view of the photographic optical system is changed step by step
Changing the viewfinder angle of viewfinder continuously
The imaging according to the above (1), characterized by having a moving means.
Shadow device. (5) The finder device is provided by the focus adjusting means.
Do not operate in synchronization with the focus adjustment operation of the imaging optical system.
Described in any of (1) to (4) above,
On-board photography device.

[0008]

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments. 1 to 4 are explanatory views of an embodiment of a photographing apparatus according to the present invention. FIG. 1 is a perspective view of the optical system block, FIG. 2 is a plan view of a zoom drive member, and FIG. 3 is an exploded perspective view of a third lens drive unit. (Configuration) In FIG. 1, reference numeral 1 denotes a ground plate for fixing each member of the optical system, and 1a denotes a pair of guide bars for moving each moving lens group in the direction of the optical axis L while holding each moving lens group. 2 is a finder 8 which is an external observation optical system.
A cam plate for displacing a movable lens group (described later) is provided with a hole 2a, a rack gear portion 2b formed on one inner edge of the hole 2a, and cam grooves 2c and 2d. Reference numeral 3 denotes a first group lens, and 4 denotes a second group lens. A second group drive dowel 4a is provided upright on the lens barrel. Reference numeral 5 denotes a third lens unit having a focusing function. Reference numeral 6 denotes a third lens drive unit for driving the third lens 5,
Details will be described with reference to FIG.

In FIG. 3, reference numeral 31 denotes a pulse sheet having a light transmitting portion and a light shielding portion, and 32 denotes a pulse sheet 31.
A photointerrupter 33 for outputting a pulse signal by rotation of the motor; a motor 33 as a driving source for a focusing operation;
Is a gear train for transmitting power, and 35 is a lead gear having a gear on the outer periphery and a threaded portion on the inner periphery, and has a rotation stopper 35a on the front end circumference. Reference numeral 36 denotes a screw that moves integrally with the third group lens 5 and engages with the internal thread of the lead gear 35. This screw 36
Stopper 36 for restricting rotation of lead gear 35
a and the screw 3
6 has a key 36b that enables movement in the optical axis L direction. Reference numeral 38 denotes a coil spring for resiliently biasing the third group lens 5, the screw 36, and the lead gear 35 with respect to the lead gear receiving surface 6b of the fixed part to eliminate backlash (play) of each part. A hole for inserting the pair of guide bars 1a, 6b is a receiving surface of the lead gear 35, 6c.
Is a key groove for inserting the key 36b, 6d is each gear shaft for holding a gear train, and 6e is a motor mounting portion for holding the motor 33.

Next, returning to FIG. 1 again, components 7 and following will be described. 7 is a lens of each of the first, second and third groups,
An image pickup unit for recording an image formed by the photographing lens composed of 4 and 5. Reference numeral 8 denotes a finder unit that is an external observation optical system, which includes a variator unit 8a and a compensator unit 8c that are optical systems for zooming.
A variator dowel 8b and a compensator dowel 8d are respectively fitted into the cam grooves 2c and 2d of the cam plate 2, respectively. Numeral 9 denotes a zoom drive member for displacing the position of the second group lens 4 (see both FIGS. 2A and 2B), and a stepwise zoom for determining the amount of movement of the zoom drive gear 9a and the second group lens 4. The drive cam 9b and the cam plate drive gear 9c for driving the cam plate 2 are integrally formed. Reference numeral 10 denotes a fixed shaft for holding the zoom driving member 9 on the main plate 1 in a rotatable state. Reference numeral 11 denotes a zoom driving unit for applying a driving force to the zoom driving member 9, and a zoom driving motor 11a. Zoom drive transmission gear 11
b. In the zoom drive cam 9b, 9b1 is a "tele" position, 9b2 is a "wide" position,
9b3 indicates a flat portion, and 9b4 indicates a displacement portion. 12
Moves the second lens unit 4 with respect to the zoom drive cam 9b.
A second group lens pressing spring for elastically biasing the group lens driving dowel 4a. Reference numeral 13 denotes a state before holding the first group lens 3, a pair of guide bars 1a, and a code plate 14 for outputting an electric signal corresponding to the amount of movement of the brush contact piece 15 held by the cam plate 2. Reference numeral 37 denotes an aperture / shutter for controlling the amount of light of the taking lens.

(Displacement Mode of Photographing Lens) Next, a displacement mode of the photographing lens in this embodiment will be described with reference to FIG. (A) is a lens movement form in optical design, (b)
8A illustrates an example of an actual lens movement mode in the present embodiment corresponding to FIG. FIG. 4 shows both (a) and (b).
The vertical axis shows the zooming direction in the range from wide to tele, the horizontal axis shows the object direction on the left side, the image forming side direction on the right side, and the locus of movement of each lens group 3, 4, 5 by zooming. I have. That is, in FIG.
The group lens 3 remains fixed from wide to tele.

When zooming from wide to tele, the second lens unit 4 moves toward the image plane by a distance a as shown by a solid line A. The third lens group 5 is a rear focus lens group having a focusing function. When the lens is focused on infinity, as shown by a solid line B, the third lens group 5 is once extended to the subject side as zooming from wide to telephoto, Then it almost returns to the wide position. On the other hand, when shooting at close range,
It is necessary to further extend to the position shown by the broken line C according to the distance, and the amount of extension is different as shown by the arrow b depending on the zoom position even at the same shooting distance.

An actual driving pattern corresponding to FIG. 1A in this embodiment is shown in FIG. Here, the first group lens 3 and the diaphragm / shutter 37 do not move while being fixed. When zooming from wide to tele, the second group lens 4 draws a step-like locus indicated by a solid line D. This is determined by the combination shape of the flat portion 9b3 and the displacement portion 9b4 of the zoom drive cam 9b. The third lens unit 5 stands by at the G position closer to the image forming plane than the infinity focus, and corresponds to the B and C curves in FIG. As shown in the drawing, immediately before the release, the lens is extended to a predetermined position corresponding to the zoom position and the shooting distance, and returns to the standby position G when the shooting ends.

(Operation) Next, the operation of the above configuration will be described. When a zoom operation button (not shown) is turned on, the zoom drive motor 11a shown in FIG. 1 is driven, the drive member 9 is rotated by the zoom drive transmission gear 11b, and the mirror of the second group lens 4 is rotated by the zoom drive cam 9b. The second group lens driving dowel 4a provided in the cylinder is pressed against the second group lens pressing spring 12, and is displaced stepwise as shown in FIG. At this time, the cam plate 2 is also moved by the cam drive gear 9c via the rack gear 2b to the zoom drive cam 9c.
Move corresponding to b. Therefore, the finder unit 8
Variator unit 8a and compensator unit 8
c is changed in magnification by the cam grooves 2c and 2d, and the brush contact piece 15 moves while abutting on the code plate.

At this time, a pattern is formed such that a signal indicating the zoom position is output from the code plate 14 only when the second group lens 4 is located on each flat portion 9b3 indicated by the stepped curve D in FIG. 4B. And a displacement portion 9b4 between the flat portions 9b3.
When the zoom operation button 11 is turned off, the driving of the zoom drive motor 11a is stopped after reaching the flat portion 9b3 even if the zoom operation button is turned off. That is, when the second group lens 4 is provided in each displacement section 9b4 in FIG. 4B, the third group lens 5 does not operate.

Next, when the first stroke of a release button (not shown) for photographing is turned on, the focal length to be set for the photographing lens is obtained from the position of the second group lens 4, that is, the output of the code plate 14, and The amount of extension of the third lens group 5 is determined by an arithmetic circuit (not shown) by obtaining the distance to the subject using a known infrared distance measuring device or the like as shown. Further, when the second stroke of the release button is turned on, the third group lens 5 is extended from the standby position G by the extension amount of the third group lens 5. That is, FIG.
Is supplied to the third group drive motor 33, and the rotation of the gear 34 at this time counts from the output of the interrupter 32 a pulse signal corresponding to the amount of extension of the screw 36, and corresponds to the amount of extension of the third group lens 5. The third group lens 5 is driven so as to stop at the set number of pulses. Further, the aperture / shutter 37 is driven so that an appropriate exposure is performed in accordance with an AE (automatic exposure) output (not shown), and an image is formed by forming an image on the imaging unit 7 shown in FIG. Thereafter, the third group lens 5 rotates the third group lens drive motor 33 in the reverse direction, returns to the standby position G, and ends a series of operations.

(Operation) As described above, since the variable power lens of the finder 8 is displaced by the continuous cam 9b, the angle of view can be set without a sense of incongruity similarly to a normal zoom finder. On the other hand, the photographing optical system is driven by the stepwise cam 9b. However, since the photographer looks only at the viewfinder 8, there is no problem in actual photographing. Further, the focal length detecting means only needs to correspond to the focal length set by the stepwise cam 9b, so that it can be greatly simplified. Further, the driving of the third group lens 5 as a focusing lens is also performed at the focal length. What is necessary is just to drive according to distance, and since a zoom lens can be treated as a lens having a plurality of focal lengths, control of a focusing operation can be greatly simplified.
Furthermore, since the focusing operation is driven only during the actual shooting operation using the release button, the variable power lens or the like of a rear focus zoom lens having a focusing function has a moving amount corresponding to the set focal length. Since it is only necessary to collectively drive the amount of extension for driving during the photographing operation, there is no need to move the rear focus lens when setting the angle of view, and there is an effect that power consumption of the photographing apparatus can be reduced.

[0019]

As described above, according to the present invention,
The angle of view of the shooting optical system can be changed easily and accurately,
Providing a shooting device that does not cause discomfort when changing the viewfinder angle of view
It can be provided.

[Brief description of the drawings]

FIG. 1 is a perspective view of an optical system block embodying the present invention.

FIG. 2 is a plan view of a zoom driving member according to the embodiment shown in FIG. 1;

FIG. 3 is a perspective view of a third lens drive unit according to the embodiment shown in FIG. 1;

FIG. 4 is an explanatory view of a displacement state of the photographing lens of the embodiment in FIG. 1;

FIG. 5 is a perspective view of an example of a conventional photographing apparatus.

FIG. 6 is a perspective view of another example of the conventional photographing apparatus.

[Explanation of symbols]

 Reference Signs List 3 First group lens 4 Second group lens 5 Third group lens 6 Third group lens drive unit 8 Viewfinder unit (external observation optical system) 9 Zoom drive member 9b Stepwise zoom drive cam 11 Zoom drive unit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) G03B 13/12 G02B ^7/ 04-7/10

Claims (5)

(57) [Claims] 1. A photographing optical system for changing a photographing angle of view stepwise, and a state of a photographing angle of view of the photographing optical system to be changed is determined.
Determining means for changing the photographing angle of view of the photographing optical system
Angle change start instruction operation of the angle of view change instruction operation means
In response to the operation, start the operation of changing the shooting angle of view of the shooting optical system
And the angle of view change of the angle of view change instruction operation means is completed.
In response to the instruction operation, the photographing optical system steps the photographing angle of view.
The current angle of view changes to the shooting angle of view
Until the determination means determines that
After continuing the shooting angle-of-view changing operation, shooting with the shooting optical system
Drive control means for stopping the angle-of-view changing operation, and the photographing light
The viewfinder is continuously synchronized with the shooting angle change operation of the academic system.
Viewfinder to change the angle of view
The photographing optical system changes the photographing angle of view in response to the operation of the step.
Focusing of the shooting optical system according to the shooting angle of view
An imaging apparatus comprising: focus adjustment means for performing a knot operation . 2. The photographing apparatus according to claim 1, wherein the photographing optical system has a cam means for changing a photographing angle of view in a stepwise manner. 3. The photographing apparatus according to claim 1, wherein the photographing optical system has a region where a photographing angle of view is changed and a region where the photographing angle of view is not changed alternately. 4. A motor and a moving means for moving by a driving force of the motor to change a photographing angle of view of the photographing optical system in a stepwise manner and continuously change a viewfinder angle of view of the viewfinder device. The photographing apparatus according to claim 1, wherein: 5. The apparatus according to claim 1 , wherein said finder device is provided with said focus adjusting means.
Operates in synchronization with the focus adjustment operation of the photographing optical system by the step
The method according to any one of claims 1 to 4, wherein
The imaging device according to the above.