JP3261549B2 - Light control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light quantity control device for a photographing apparatus, and more particularly to a light quantity control device capable of miniaturization.

[0002]

2. Description of the Related Art Conventionally, as a light amount control device of a photographing apparatus, there is one disclosed in, for example, JP-A-4-56934 or JP-A-62-26710. That is, as shown in FIGS. 18 and 19, a shutter device as a conventional light amount control device includes 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 disposed between the front group lens 23 and the rear group lens 24, and open and close the lens opening 29 . Front group lens
23 is supported by a front lens barrel 25, and the rear lens group 24 is supported by a rear lens barrel. Front lens barrel 25 and rear lens barrel 26
Flanges are formed on the opposite end faces of the
The shutter chamber 27 is configured in the state of being connected. A pair of light-shielding blades 21 and 22 are housed in the shutter chamber 27, and constitute a so-called between shutter. Shading feathers 21 and 22
Is rotatably supported at its periphery by a pin 28.

[0003] A known shutter driving device 30 is attached to the outer periphery 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. The drive shaft 31 of the drive device 30 is slidably engaged with the formed inclined grooves (not shown) in opposite directions, and the light-shielding blades 21 and 22 are opened and closed by rotating the drive shaft 31. It has become.

[0004]

By the way, at present, as lenses are becoming smaller and lighter, it is necessary to reduce the size of the light amount control member for controlling the amount of light entering the lens group. However, in the conventional light amount control member, although the thickness of the light shielding blade for controlling the light amount is reduced by reducing the thickness, a sliding engagement member for driving the light shielding blade is used. Since 35 is indispensable, it has been difficult to reduce the size of the space in which the sliding engagement member 35 is provided.

The present invention has been made in view of such circumstances, and operates a light amount control member via a lens to eliminate a space for providing a drive mechanism such as a sliding engagement member of the light amount control member. It is an object of the present invention to provide a light quantity control device capable of miniaturization.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention provides 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. Rotating means for rotating a predetermined lens; and an optical axis of the lens group around the predetermined lens.
A projecting member provided to project in a parallel direction;
Engagement provided on the light quantity control member so as to engage with the material
And a groove, and a configuration in which the, an interlocking means for interlocking the opening and closing operation of the light quantity control member and rotation of the predetermined lens.

[0007]

[Action] amount of light morphism entering the lens group to be supported by the support member is controlled by the light amount control member. Here, the predetermined lens is rotated by the rotation unit. According to this configuration, the interlocking unit is configured to rotate around the peripheral portion of the predetermined lens.
Is provided so as to protrude in a direction parallel to the optical axis of the lens group.
A protruding member, and the light amount control so as to engage with the protruding member.
An engagement groove provided in the control member is provided, and the rotating operation of the predetermined lens and the opening / closing operation of the light amount control member are interlocked by interlocking means.

That is, an engagement groove provided in the light amount control member
A protruding portion provided on the periphery of a predetermined lens
By engaging the material, by a rotating operation of a predetermined lens rotated from the outside of the support member or the like, through the interlocking means ,
The light amount control member is driven to open and close , and the driving mechanism such as the sliding engagement member of the light amount control member is moved from the outer periphery of the lens group.
Need not be provided on the outside , and the installation space for the drive mechanism is not required.

[0009]

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

The rotating lens 10 has a tooth space 11 on the outer peripheral portion on the subject side.
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 driving gear 4 supported by a motor shaft 3 meshes with the tooth groove 11. ing.

Further, as a configuration according to the present invention, three pins 13a, 13b and 13c constituting an interlocking means are protrudingly provided on the film side bottom portion 14 of the rotating lens 10. On the other hand, the fixed lens 20 has an outer peripheral portion 21 supported by the lens barrel 1. In this embodiment, the diaphragm 30 is composed of three diaphragm plates 32a, 32b, and 32c, and each of the fulcrums 22a, 22 provided on the subject-side bottom surface portion 21 of the fixed lens 20.
The lens swings from the center to the periphery of the lens opening with the b and 22c as the swing center. An opening is formed in the center according to the swing amount, and the incident light passes therethrough. The three aperture plates 32a,
By controlling the swing amounts of 32b and 32c, the effective aperture diameter can be defined, and by controlling the swing time, the exposure time can be defined. Therefore, the diaphragm 30 constitutes a light amount control member.

Further, the aperture plates 32a, 32b and 32c are respectively provided with engaging grooves 35a, 35b and 35c which constitute interlocking means.
Are provided, and the three pins 13a, 13b, 13c are engaged. According to the above configuration, the drive gear 4 and the tooth space 11
When the motor 2 rotates, the rotating lens 10 rotates on the inner peripheral portion of the lens barrel 1 and further rotates the pins 13a and 13a.
b, 13c are engaged with the engagement grooves 35a, 35b, and 35c, so that when the rotary lens 10 rotates, the aperture plates 32a, 32b, and 32
c performs the opening and closing operation.

That is, when the motor 2 rotates, the light amount is controlled by the diaphragm 30 via the rotating lens 10.
That is, according to the first embodiment, the aperture plate 32 for controlling the amount of light
a, 32b and Der can be reduced in weight by reducing the thickness thereof for 32c Rutotomoni, the narrowed Riita 32a, since the 32b and 32c rotating lens 10 is driven, the narrowed Riita 32a,
A drive member for driving 32b and 32c is not required, and, for example, the rotating lens 10 and the fixed lens 20 can be provided close to each other, which has the effect of reducing the size and weight.

Further, since the rotating lens 10 and the fixed lens 20 can be provided close to each other, the precision of optical axis alignment of the lens groups can be further improved, and the quality can be improved. Becomes Also, the aperture plates 32a, 32
b and 32c may be urged toward the center of the lens opening by a spring or the like, that is, in a direction to narrow the lens opening. In this case, the stop plates 32a, 32b, and 32c can prevent unnecessary light from entering the imaging device, 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. The light-emitting element 41 and the light-receiving element 42 are provided in the openings 16 provided in the lens barrel 1.
This makes it possible to optically detect the rotational position of the lens. Preferably, the opaque portion 17 is painted black in order to prevent the internal reflection of the rotating lens 10 from occurring.

Since the light emission from the light emitting element 41 may leak during AE (photometry), it is desirable to prohibit the light emission. However, position detection is performed using light outside the sensitivity of the image pickup element. May go. 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 relating to the detection of the rotational position of the rotary lens 10, there is also a configuration as shown in FIGS.

That is, as shown in FIG. 4, an opaque portion 18f is provided obliquely on the outer peripheral portion 15 of the rotating lens 10 on the film side, and the absolute rotation angle is determined by measuring the shielding ratio of the amount of light from the light emitting element. There is something I asked for. As shown in FIG. 5, an opaque portion 18g is intermittently provided on an outer peripheral portion 15 of the rotating lens 10 on the film side, and a relative rotation angle is obtained by counting a shielding pulse of a light amount from a light emitting element. 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 provided obliquely on the outermost side of the film side bottom portion 14 of the rotating lens 10, and the light emitting element 43 and the light receiving element 44 face the film side bottom portion 14.
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. Incidentally, since the imaging element is usually a rectangle included in the image circle (focus plane), the configuration can be realized by disposing the light emitting element 43 and the light receiving element 44 at positions not covering the imaging element. It is.

As shown in FIG. 7, a projection 48 is provided on the outer peripheral portion 15 of the rotating lens 10 on the film side.
In some cases, the rotation angle is obtained by detecting the movement of 48 using 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 in the first embodiment are denoted by the same reference numerals, and the description is omitted.

In the second embodiment, a transparent cover 50 covers the outer peripheral portion of the lens barrel 1 and the surface portion on the subject side.
An aperture 55 is provided between the rotary lens 50 and the rotary lens 10. In this embodiment, three aperture plates 55a, 55b, and 55c are provided, and each of the fulcrums 52a, 52b, and 52c provided on the surface portion 51 of the cover 50 on the subject side swings around the center of the lens aperture. It swings from the center to the periphery, an opening is formed in the center according to the swing amount, and the incident light passes through. The effective aperture diameter can be defined by controlling the swing amounts of the three diaphragm plates 55a, 55b and 55c, and the exposure time can be defined by controlling the swing time. Therefore, the diaphragm 55 constitutes a light amount control member.

Further, each of the aperture plates 55a, 55b and 55c is provided with an engaging groove 56a or the like constituting an interlocking means, and the three pins 13a and the like are engaged. According to the above configuration, since the rotating lens 10 rotates around the inner peripheral portion of the lens barrel 1 and the pins 13a and the like are engaged with the engagement grooves 56a and the like, the diaphragm plate is rotated when the rotating lens 10 rotates. 55a, 55b and 55c open and close.

That is, when the motor 2 is rotated, the light amount is controlled by the diaphragm 55 through the rotary lens 10.
That is, the second embodiment has the same functions and effects as those of the first embodiment. It goes without saying that the same applies to the case where an infrared filter or a phase difference filter is interposed on the front surface instead of the transparent cover 50.

Next, a third embodiment according to the present invention will be described with reference to FIGS. The same components as those in the first embodiment are denoted by the same reference numerals, and the description is omitted. Book 3
Also in the embodiment, the rotating lens 60 has a tooth groove (not shown) in the outer peripheral portion on the subject side, and a rotation supporting portion is provided in the outer peripheral portion in the center in the width direction. lens
Numeral 60 is rotatably supported by the lens barrel 1 (not shown) as a support member. Further, the motor 2 is provided as a rotating means for rotating the rotating lens 60 (not shown).

Further, as a configuration according to the third embodiment,
A single pump piece 62 constituting an interlocking means is provided protrudingly from a film-side bottom surface portion 61 of the rotating lens 60. Further, the film-side bottom surface portion 61 of the rotating lens 60 is fitted into the end of the fixed lens 70. On the other hand, the fixed lens 70 has a fitting part 71 whose outer peripheral part is supported by the lens barrel 1 and faces the film-side bottom part 61 of the rotating lens 60. The fitting portion 71
Is provided with a fluid reservoir 76 in which the pump piece 62 can move. Further, on the inner periphery of the fitting portion 71, there is provided a rubber-like film 75 having an opening 73 at the center and formed in a bellofram shape and partially having an operating element 74 made of fluid. Here, the operating element 74 is anisotropic and expands linearly so that the opening 73 is reduced when the working fluid flows into the operating element 74 (see FIG. 12). The operating element 74
Communicates with the fluid reservoir 76 through a communication ring 77.

According to the above configuration, since the pump piece 62 is fitted into the fluid reservoir 76 and moves in accordance with the rotation of the rotary lens 60, the rotary lens 60 is turned when the motor 2 rotates. 1, the pump piece 62 moves in the fluid reservoir 76, and supplies the working fluid in the fluid reservoir 76 to the operating element 74 via the communication ring 77. Therefore, the operating element 74 expands linearly and the rubber-like film 75 extends,
Reduce 73. When the motor 2 rotates in the opposite direction, the working fluid inside the working element 74 is collected through the communication ring 77.
Then, the operation element 74 contracts and the rubber film 75 also contracts, and the opening 73 is enlarged.

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

That is, the third embodiment has the same operation and effect as the first embodiment. In the embodiment described above, the motor 2
Was used to rotate the rotating lenses 10 and 60,
In order to further reduce the size, an embodiment in which a mechanism other than the motor 2 is used as the structure of the rotating means for rotating the rotating lenses 10 and 60 will be described with reference to FIGS. FIG. 13 to FIG.
In FIG. 16, for the sake of simplicity, only the rotating lens is shown, and other components are omitted.

The rotating lens 81 shown in FIG. 13 is an integrated part obtained by sintering a magnetic powder 83 on a glass lens 82 and magnetizing this to form a rotor. Alternatively, the magnetic powder 83 may be injection molded around the glass lens 82. In addition, magnetic powder
When the pins 13a, 13b, and 13c are formed on the 83, it is possible to prevent torque for driving the diaphragm from directly acting on the glass lens 82, thereby preventing the glass lens 82 from being distorted. It is convenient.

The rotary lens 85 shown in FIG. 14 is formed by molding the optical part with a transparent resin 86 by two-color molding of resin, molding the periphery with a resin 87 containing magnetic powder, and magnetizing this to form a rotor. . A rotating lens 89 shown in FIG. 15 has a coil 91 formed on a lens surface 90 by a transparent pattern used for liquid crystal wiring and the like, and further includes an electrode pattern 92 for supplying power to the coil 91 at an outer peripheral portion. It is formed in 93 and can be supplied with power by a brush 94.

The rotating lens 95 shown in FIG. 16 has a lens barrel 96 formed integrally, and has a coil pattern on an outer periphery 97 of the lens barrel 96.
98 is pasted. Further, since the rotating lens is configured to rotate in the lens barrel, lubrication for the rotation is required. However, in consideration of optical effects, it is desirable to use a solid lubricant or a self-lubricating material. In addition, even if the lubricant seeps into the optical part, it is possible to take measures such as detecting the lubricant and setting a soft focus in signal processing of the image sensor.

As shown in FIG. 17, a gap 99 may be formed between the pin 13a and the lens portion. Thereby, 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 are transmitted to the lens unit, thereby preventing the lens unit from being distorted. Note that 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 turning means for turning the predetermined lens,
Project in the direction parallel to the optical axis of the lens group
A projecting member provided so as to engage with the projecting member.
And an interlocking means for interlocking a predetermined lens turning operation and an opening / closing operation of the light amount control member with the engagement groove provided in the light amount control member. Lens
The light amount control member is opened via the interlocking means
As a result, the drive mechanism such as the sliding engagement member of the light amount control member does not need to be provided outside the outer periphery of the lens group , and the installation space of the drive mechanism can be saved.
There is an effect that the size can be reduced.

[Brief description of the 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 the 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 related to the position detection.

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

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

FIG. 7 is a perspective view showing another embodiment of the rotary lens according to the 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 cross-sectional view of a camera shutter device according to 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 transverse cross-sectional view taken along line BB in FIG. 18.

[Explanation of symbols]

1 barrel 2 motor 10 rotates the lens 11 tooth groove 13a pin 13b pin 13c pins 16 transparent portions 17 opaque portion 20 fixed lens 30 aperture 32a aperture plate 32b stop 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)

(57) [Claims] 1. A light amount control device comprising: 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. Means, at the periphery of the predetermined lens, parallel to the optical axis of the lens group
A projecting member provided to project in the direction;
An engagement groove provided on the light amount control member so as to engage with the engagement groove;
The provided, the light quantity control device, characterized in that provided, and interlocking means for interlocking the opening and closing operation of the light quantity control member and rotation of the predetermined lens.