JPH06332033A - Light quantity controller - Google Patents

Abstract

PURPOSE:To eliminate a space for providing the driving mechanism of a light quantity control member and to attain miniaturization by turning a prescribed lens and linking the turn of a lens with the opening/closing actions of the light quantity control member controlling the entering of light into a lens group. CONSTITUTION:Pins 13 constituting interlocking means are provided on the film side bottom surface part 14 of a rotary lens 10 and engaged with the engaging grooves 35a-35c of diaphragm plates 32a-32c. When a motor 2 is turned, the rotary lens 10 is turned on the inner peripheral part of a lens-barrel and the diaphragm plates 32a-32c take the opening/closing actions. In other words, the motor 2 is turned to control a light quantity by a diaphragm 30 via the rotary lens 10. Therefore, the thickness of the diaphragm plates controlling the light quantity is reduced to lighten weight and simultaneously, the diaphragm plates 32a-32c drive the rotary lens 10, so that the driving members of the diaphragm plates 32a-32c are dispensed and for instance, the rotary lens 10 and a fixed lens 20 can be provided adjacently. Thus, the miniaturization and the lightening of weight can be attained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light amount control device for a photographing device, and more particularly to a light amount control device which can be miniaturized.

[0002]

2. Description of the Related Art Conventionally, as a light quantity control device for a photographing device, there is one disclosed in, for example, Japanese Patent Application Laid-Open No. 4-56934 or Japanese Utility Model Laid-Open No. 62-6710. That is, as shown in FIGS. 18 and 19, a shutter device as a conventional light amount control device is configured to include a pair of light shielding blades 21 and 22 corresponding to a light amount control member. The pair of light-shielding blades 21 and 22 are arranged between the front lens group 23 and the rear lens group 24 to open and close the lens aperture. Front lens group 23
Are supported by a front lens barrel 25, and the rear lens group 24 is supported by a rear lens barrel 26. Front lens barrel 25 and rear lens barrel 26 are formed with flanges on their opposing end surfaces, respectively, and constitute a shutter chamber 27 in a coupled state. The shutter chamber 27 houses a pair of light-shielding blades 21 and 22 and constitutes a so-called between shutter. The light-shielding blades 21 and 22 are rotatably supported by a pin 28 at their peripheral portions.

A known shutter driving device 30 is attached to the outer peripheral portion of the rear lens barrel 26, and a pair of light-shielding blades 21 and 22 pivotally supported by the front lens barrel 25 and the rear lens barrel 26 are attached to the shutter lens drive device 30. The drive shaft 31 of the drive device 30 is slidably engaged with the formed inclined grooves (not shown) in opposite directions, and the drive shaft 31 is rotated to open and close the light shielding blades 21 and 22. It is like this.

[0004]

By the way, at the present time when lenses tend to be smaller and lighter, it is necessary to reduce the size of a light amount control member that controls the amount of light entering a lens group. However, in the conventional light amount control member, although the light shielding blade for controlling the light amount has been made thinner and lighter, the sliding engagement member for driving the light shielding blade has been performed. Since 35 is indispensable, it is difficult to reduce the size of the space for providing the sliding engagement member 35.

The present invention has been made in view of the above circumstances, and by operating the light amount control member via a lens, a space for providing a drive mechanism such as a sliding engagement member of the light amount control member is eliminated. It is an object of the present invention to provide a light quantity control device that can be downsized.

[0006]

For this reason, the present invention provides a light quantity control device having a lens group, a support member for supporting the lens group, and a light quantity control member for controlling the quantity of light entering the lens group. The rotating means for rotating a predetermined lens and the interlocking means for interlocking the rotation of the lens and the opening / closing operation of the light amount control member are provided.

[0007]

The amount of light entering the lens group supported by the support member is controlled by the light amount control member. Here, the predetermined lens is rotated by the rotation means, but according to such a configuration, the rotation of the lens and the opening / closing operation of the light amount control member are linked by the linking means.

That is, for example, the light amount control member is driven through a predetermined lens that is rotated from the outside of the support member, and it is necessary to provide a drive mechanism such as a sliding engagement member of the light amount control member. No more space is required for installing the drive mechanism.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. However, it is not limited to the following examples. 1 to 7 show a first embodiment according to the present invention. As shown in FIGS. 1 and 2, the shutter device of the camera includes a camera lens group including a plurality of lenses. This lens group is divided into a rotary lens 10 located on the subject side and a fixed lens 20 located on the film side.
A diaphragm 30 is provided between the fixed lens 20 and the fixed lens 20.

The rotary lens 10 has a tooth groove 11 on the outer peripheral portion on the object side.
Further, a rotation support portion 12 is provided on the outer peripheral portion of the center portion in the width direction, and the rotation lens 10 is rotatably supported by the lens barrel 1 as a support member. A motor 2 is fixed to the outer peripheral portion of the lens barrel 1 as a rotating means for rotating the rotary lens 10, and a drive gear 4 supported by a motor shaft 3 meshes with the tooth groove 11. ing.

Further, as a structure according to the present invention, three pins 13a, 13b, 13c forming interlocking means are provided on the bottom surface 14 of the rotary lens 10 on the film side so as to project therefrom. On the other hand, the outer periphery 21 of the fixed lens 20 is supported by the lens barrel 1. Further, the diaphragm 30 is composed of three diaphragm plates 32a, 32b and 32c in the present embodiment, and each fulcrum 22a, 22 provided on the subject side bottom surface portion 21 of the fixed lens 20.
It swings from the central portion of the lens opening toward the peripheral portion around b and 22c as the swinging center, and an opening is formed in the central portion according to the swinging amount, and incident light passes through. The three diaphragm plates 32a,
The effective aperture diameter can be defined by controlling the swing amount of 32b and 32c, and the exposure time can also be defined by controlling the swing time. Therefore, the diaphragm 30 constitutes a light amount control member.

Further, the throttle plates 32a, 32b and 32c are provided with engaging grooves 35a, 35b and 35c, respectively, which form interlocking means.
Is provided, and the three pins 13a, 13b, 13c are engaged with each other. According to the above configuration, the drive gear 4 and the tooth groove 11
Since the and are meshed with each other, when the motor 2 rotates, the rotary lens 10 rotates on the inner peripheral portion of the lens barrel 1, and the pins 13a, 13
Since b and 13c are engaged with the engaging grooves 35a, 35b and 35c, when the rotary lens 10 is rotated, the diaphragm plates 32a, 32b and 32 are rotated.
c opens and closes.

That is, when the motor 2 is rotated, the light amount is controlled by the diaphragm 30 via the rotary lens 10.
That is, according to the first embodiment, the diaphragm plate 32 for controlling the amount of light is used.
The a, 32b, and 32c can be made thin by reducing their thickness, and the diaphragm plates 32a, 32b can be made lighter.
And 32c are driven by the rotary lens 10, the diaphragm plate 32
A driving member for driving a, 32b, and 32c is not required, and for example, the rotary lens 10 and the fixed lens 20 can be provided in close proximity to each other, and the size and weight can be reduced.

Further, since the rotary lens 10 and the fixed lens 20 can be provided close to each other, the precision of the optical axis alignment of the lens group can be further improved, and the quality can be improved. Becomes In addition, the diaphragm plates 32a, 32
b and 32c may be urged by a spring or the like toward the center of the lens opening, that is, in the direction of squeezing the lens opening. In this case, the diaphragm plates 32a, 32b, and 32c can prevent unwanted light from entering the image sensor, and can also serve as a lens barrier.

Further, it is necessary to detect the current rotational position of the rotary lens 10, but in the first embodiment, as shown in FIG. 3, the rotary lens 10 is transparent to the film side outer peripheral portion 15. The portion 16 and the opaque portion 17 are provided, and the light emitting element 41 and the light receiving element 42 are provided in the opposing openings provided in the lens barrel 1. This makes it possible to optically detect the rotational position of the lens. The opaque portion 17 is preferably painted black in order to prevent occurrence of internal reflection on the rotary lens 10.

Since the light emitted from the light emitting element 41 may leak during AE (photometry), it is desirable to prohibit the light emission, but position detection is performed using light outside the sensitivity of the image pickup element. You can go. Alternatively, light from a light emitting diode for distance measurement or light from a light emitting element for a self-timer may be used.
Incidentally, as a configuration related to the detection of the rotational position of the rotary lens 10, there is a configuration as shown in FIGS.

That is, as shown in FIG. 4, an opaque portion 18f is obliquely provided on the film-side outer peripheral portion 15 of the rotary lens 10, and the absolute rotation angle is determined by measuring the shielding ratio of the light amount from the light emitting element. There are things I have asked for. As shown in FIG. 5, an opaque portion 18g is intermittently provided on the outer peripheral portion 15 of the rotary lens 10 on the film side, and a relative rotation angle is obtained by counting the light quantity shielding pulses. There is. In this case, in order to obtain the absolute rotation angle, it is necessary to detect the starting position.

As shown in FIG. 6, an opaque portion 18h is obliquely provided on the outermost side of the bottom surface 14 on the film side of the rotary lens 10, and the light emitting element 43 and the light receiving element 44 are opposed to the bottom surface 14 on the film side.
Is provided, and the absolute rotation angle is obtained by measuring the shielding ratio of the amount of light in the same direction as the lens opening from the light emitting element 43. Since the image pickup device is usually a rectangle enclosed in the image circle (focus plane), by disposing the light emitting device 43 and the light receiving device 44 at a position not covered by the image pickup device, the configuration becomes possible. Is.

Further, as shown in FIG. 7, a protrusion 48 is provided on the outer peripheral portion 15 of the rotary lens 10 on the film side, and the protrusion 48 is formed by the rotation.
In some cases, the rotation angle is obtained by detecting the movement of 48 with a photo interrupter or the like. Next, FIG.
A second embodiment according to the present invention will be described with reference to FIG.
The same components as those of the first embodiment described above are designated by the same reference numerals and the description thereof will be omitted.

In the second embodiment, the transparent cover 50 covers the outer peripheral portion of the lens barrel 1 and the surface portion on the subject side.
A diaphragm 55 is disposed between the rotary lens 10 and the rotary lens 10. In this embodiment, the diaphragm is composed of three diaphragm plates 55a, 55b and 55c, and the fulcrum points 52a, 52b and 52c provided on the object side surface portion 51 of the cover 50 are used as swing centers of the lens aperture. The light oscillates from the central portion to the peripheral portion, and an opening is formed in the central portion according to the amount of the oscillation, and incident light passes through. The effective aperture diameter can be defined by controlling the swing amount of the three diaphragm plates 55a, 55b and 55c, and the exposure time can also be defined by controlling the swing time. Therefore, the diaphragm 55 constitutes a light amount control member.

Further, each of the diaphragm plates 55a, 55b and 55c is provided with an engagement groove 56a or the like constituting an interlocking means, and the three pins 13a or the like are engaged with the engagement grooves 56a. According to the above configuration, since the rotary lens 10 is rotated in the inner peripheral portion of the lens barrel 1 and the pins 13a and the like are engaged with the engaging grooves 56a and the like, when the rotary lens 10 is rotated, the diaphragm plate is rotated. 55a, 55b and 55c perform the opening / closing operation.

That is, when the motor 2 is rotated, the light amount is controlled by the diaphragm 55 via the rotary lens 10.
That is, also in the second embodiment, the same operation and effect as those of the above-described first embodiment are exhibited. Incidentally, it goes without saying that the same applies to the case where an infrared filter or a phase difference filter is provided on the front surface instead of the transparent cover 50.

Next, a third embodiment of the present invention will be described with reference to FIGS. The same components as those of the first embodiment described above are designated by the same reference numerals and the description thereof will be omitted. Book Third
Also in the embodiment, the rotary lens 60 is provided with a tooth groove in the outer peripheral portion on the object side (not shown), and the rotation supporting portion is provided in the outer peripheral portion at the center in the width direction. lens
60 is rotatably supported by a lens barrel 1 (not shown) as a support member. The motor 2 is provided as a rotating means for rotating the rotary lens 60 (not shown).

Further, as the structure according to the third embodiment,
On the film-side bottom surface portion 61 of the rotary lens 60, one pump piece 62 constituting the interlocking means is provided so as to project. Further, the film side bottom surface portion 61 of the rotating lens 60 is fitted into the end portion of the fixed lens 70. On the other hand, the fixed lens 70 has an outer peripheral portion supported by the lens barrel 1 and a fitting portion 71 facing the film side bottom surface portion 61 of the rotary lens 60. The fitting portion 71
A fluid reservoir 76 to which the pump piece 62 can move is provided in a part of the above. Further, on the inner circumference of the fitting portion 71, a rubber-like film 75 having an opening 73 in the central portion, formed in a bellows shape, and partially having a fluid operation element 74 is provided. Here, the operating element 74 has an anisotropy that linearly expands so as to reduce the opening 73 when the operating fluid flows into the operating element 74 (see FIG. 12). In addition, operating element 74
Communicates with the fluid reservoir 76 via a communication loop 77.

According to the above construction, the pump piece 62 is fitted in the fluid reservoir 76 and moved in accordance with the rotation of the rotary lens 60. Therefore, when the motor 2 is rotated, the rotary lens 60 is moved to the lens barrel. The pump piece 62 moves in the fluid reservoir 76, and the working fluid in the fluid reservoir 76 is supplied to the operating element 74 via the communication loop 77. Therefore, the operating element 74 expands linearly, the rubber-like film 75 extends, and the opening
Shrink 73. When the motor 2 rotates in the opposite direction, the working fluid inside the working element 74 collects via the communication passage 77.
It is discharged to 76, the operating element 74 contracts and the rubber-like film 75 also contracts, and the opening 73 is enlarged.

Therefore, in the third embodiment, the operating element is
The 74 and the rubber-like film 75 constitute a light amount control member, and the effective opening diameter can be regulated by controlling the moving amount of the pump piece 62, and the exposure time can be also controlled by controlling the moving time. Can be defined. That is, when the motor 2 rotates, the light amount control by the operating element 74 and the rubber-like film 75 is performed via the rotating lens 60.

That is, also in the third embodiment, the same action and effect as those of the above-mentioned first embodiment are exhibited. In the embodiment described above, the motor 2 as the rotating means is used.
Although it was configured to rotate the rotating lenses 10 and 60 by,
In order to further reduce the size, an embodiment using a structure other than the motor 2 as the structure of the rotating means for rotating the rotary lenses 10 and 60 will be described with reference to FIGS. 13 to 16. Figures 13 to
In FIG. 16, for simplicity, only the rotary lens is shown and other components are omitted.

The rotary lens 81 shown in FIG. 13 has a construction in which a magnetic powder 83 is sintered on a glass lens 82 to form an integrated component, which is magnetized to form a rotor. Further, the magnetic powder 83 may be injection-molded around the glass lens 82. In addition, magnetic powder
When the pins 13a, 13b, 13c are formed on the 83, the torque for driving the diaphragm can be prevented from directly acting on the glass lens 82, and the distortion of the glass lens 82 can be prevented. , Convenient.

In the rotary lens 85 shown in FIG. 14, the optical part is molded by a two-color molding of a resin with a transparent resin 86, the periphery is molded with a resin 87 containing magnetic powder, and this is magnetized to form a rotor. . A rotary lens 89 shown in FIG. 15 is one in which a coil 91 is formed on a lens surface 90 in a transparent pattern used for liquid crystal wiring and the like, and an electrode pattern 92 for supplying power to the coil 91 is provided on an outer peripheral portion. The brush 94 is formed so that power can be supplied by the brush 94.

A rotary lens 95 shown in FIG. 16 has a lens barrel portion 96 formed integrally, and has a coil pattern on the outer periphery 97 of the lens barrel portion 96.
98 is pasted. Further, since the rotary lens is configured to rotate within the lens barrel, it is necessary to lubricate the rotation. However, in view of optical effects, it is desirable to use a solid lubricant or a self-lubricant. Further, even if the lubricant oozes out to the optical part, it is possible to detect it and take measures such as soft focus in signal processing of the image sensor.

Further, as shown in FIG. 17, a gap 99 may be formed between the pin 13a and the lens portion. As a result, it is possible to prevent the residual stress when the pins 13a and the like are formed by injection molding or the like, and the stress at the time of driving from being transmitted to the lens portion and the distortion of the lens portion. A rib may be formed instead of the gap 99.

[0032]

As described above, according to the light quantity control device of the present invention, the rotating means for rotating the predetermined lens,
Since the interlocking means for interlocking the rotation of the lens and the opening / closing operation of the light quantity control member is provided, the light quantity control member is driven through the predetermined lens, and the sliding member of the light quantity control member is driven. Since there is no need to provide a drive mechanism such as a combination member, the installation space can be saved and the size can be reduced.

[Brief description of drawings]

FIG. 1 is a partial sectional view of a shutter device of a camera showing a first embodiment of the present invention.

FIG. 2 is a perspective view for explaining assembly of the device according to the first embodiment.

FIG. 3 is a perspective view for explaining position detection of the rotary lens according to the first embodiment.

FIG. 4 is a perspective view showing another embodiment of the rotary lens relating to the position detection.

FIG. 5 is a perspective view showing another embodiment of the rotary lens for position detection.

FIG. 6 is a perspective view showing another embodiment of the rotary lens relating to the position detection.

FIG. 7 is a perspective view showing another embodiment of the rotary lens for position detection.

FIG. 8 is a partial sectional view of a shutter device of a camera showing a second embodiment of the present invention.

FIG. 9 is a partial sectional view of a shutter device of a camera showing a third embodiment of the present invention.

FIG. 10 is a perspective view for explaining assembly of the device according to the third embodiment.

FIG. 11 is a front view for explaining the operation of the device according to the third embodiment.

FIG. 12 is a front view for explaining assembly of the device according to the third embodiment.

FIG. 13 is a sectional view showing another embodiment of the rotating lens.

FIG. 14 is a sectional view showing another embodiment of the rotating lens.

FIG. 15 is a perspective view showing another embodiment of the rotating lens.

FIG. 16 is a perspective view showing another embodiment of the rotating lens.

FIG. 17 is a perspective view showing another embodiment of the rotating lens.

FIG. 18 is a partial cross-sectional view of a conventional shutter device.

19 is a cross-sectional view taken along the line BB in FIG.

[Explanation of symbols]

 1 lens barrel 2 motor 8 pin bar 10 rotating lens 11 tooth groove 13a pin 13b pin 13c pin 16 transparent part 17 opaque part 20 fixed lens 30 diaphragm 32a diaphragm plate 32b diaphragm plate 32c diaphragm plate 35a engaging groove 35b engaging groove 35c engaging Groove 41 Light emitting element 42 Light receiving element 50 Cover 55 Aperture 60 Rotating lens 62 Pump piece 70 Fixed lens 74 Operating element

Claims (1)

[Claims] 1. A light amount control device having a lens group, a support member for supporting the lens group, and a light amount control member for controlling the amount of light entering the lens group. A light quantity control device comprising: means and interlocking means for interlocking the rotation of the lens and the opening / closing operation of the light quantity control member.