Light intensity control devices and optical instruments

Abstract

This reduces the difference in light intensity between the two optical systems that make up the compound eye. [Solution] The light intensity control device controls the light intensity in a first optical system 201 and a second optical system 301 arranged in parallel. The device has a single drive source 105, a first aperture driven by the drive source to change the light intensity of the first optical system, and a second aperture driven by the drive source to change the light intensity of the second optical system. Furthermore, it has adjustment mechanisms 107 and 117 that can adjust the amount of light passing through at least one of the first aperture and the second aperture independently of the amount of light passing through the other, without the drive source.

Description

Technical Field

[0001] The present invention relates to a light quantity control device for controlling the light quantity of a compound eye optical system.

Background Art

[0002] A light quantity control device that drives the aperture blades provided in each of two optical systems constituting a compound eye optical system with one drive source is disclosed in Patent Document 1.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the light quantity control device of Patent Document 1, there is a possibility that a light quantity difference may occur between the two optical systems due to variations in manufacturing errors and assembly errors of the aperture blades provided in each of the two optical systems and the members for driving them.

Means for Solving the Problems

[0005] One aspect of the present invention is a light intensity control device that controls the light intensity in a first optical system and a second optical system arranged in parallel. The light intensity control device is characterized by comprising a single drive source, a first aperture driven by the drive source to change the light intensity of the first optical system, a second aperture driven by the drive source to change the light intensity of the second optical system, and an adjustment mechanism that allows the amount of light passing through at least one of the first and second apertures to be adjusted independently of the amount of light passing through the other, without the drive source. Another aspect of the present invention is a light intensity control device that comprises a first aperture driven by the first drive source to change the light intensity of the first optical system, a second aperture driven by the second drive source to change the light intensity of the second optical system, and an adjustment mechanism that allows the amount of light passing through at least one of the first and second apertures to be adjusted independently of the amount of light passing through the other, without the first and second drive sources. An optical instrument equipped with the above light intensity control device and the first and second optical systems also constitutes another aspect of the present invention. [Effects of the Invention]

[0006] According to the present invention, the difference in light intensity between two optical systems can be reduced. [Brief explanation of the drawing]

[0007] [Figure 1] This figure shows the configuration of a stereoscopic imaging system equipped with a light intensity control device in the embodiment. [Figure 2] Rear perspective view of the light intensity control device of Example 1 [Figure 3] Exploded perspective view of the light intensity control device of Example 1 [Figure 4] Diagram showing the adjustment mechanism of the light intensity control device in Example 1. [Figure 5] Diagram showing the operation of the adjustment mechanism in Example 1 [Figure 6] Figure showing the effect of the adjustment mechanism in Example 1 [Figure 7] Rear view of the light intensity control device in Example 2 [Figure 8] Diagram showing the operation of the adjustment mechanism in Example 2 [Figure 9] Rear view of the light intensity control device in Example 3 [Figure 10] Diagram showing the operation of the adjustment mechanism in Example 3 [Figure 11] Perspective view of the lens unit incorporating the light intensity control device of Example 4. [Figure 12] Figure showing the operation of the adjustment mechanism in Example 4. [Figure 13] Figure showing the effect of the adjustment mechanism in Example 4 [Modes for carrying out the invention]

[0008] Hereinafter, embodiments of the present invention will be described with reference to the drawings. [Examples]

[0009] Figure 1 shows the configuration of an imaging device 10 as an optical device equipped with a light intensity control device in Embodiment 1. The imaging device 10 has a camera body 1 and a stereo optical unit 20 provided on the camera body 1. The stereo optical unit 20 includes a first optical unit 2 and a second optical unit 3. In this embodiment, the stereo optical unit 20 is integrally fixed to the camera body 1, but the stereo optical unit 20 may be a detachable interchangeable lens (optical device) attached to the camera body 1.

[0010] The first optical unit 2 includes a first optical system 201, a lens control unit 204, and a lens communication unit 205. The second optical unit 3 includes a second optical system 301, a lens control unit 304, and a lens communication unit 305. The first optical system 201 and the second optical system 301 have the same optical configuration and are arranged in parallel to each other on the left and right sides so that their optical axes OA1 and OA2 are parallel to each other. In the following description, the direction in which the optical axes OA1 and OA2 extend is called the optical axis direction. The first optical system 201 and the second optical system 301 are each driven in the optical axis direction for zooming and focusing by a zoom motor and a focus motor, which are not shown as drive sources. The first optical system 201 and the second optical system 301 may consist of one or more lenses, or they may include optical elements other than lenses, such as prisms and mirrors. Furthermore, the first optical system 201 and the second optical system 301 may include a shift lens that moves in a direction perpendicular to the optical axes OA1 and OA2 in response to shaking of the imaging device 10 due to hand shake or the like to reduce (correct) image shake.

[0011] Furthermore, the stereo optical unit 20 has a single light intensity control device 100 that is provided in common to the first optical system 201 and the second optical system 301. The light intensity control device 100 has a first aperture provided for the first optical system 201, a second aperture provided for the second optical system 301, and an aperture motor 105 as a single drive source provided in common to the first and second apertures. The first and second apertures are driven by the aperture motor 105, which changes the diameter of the aperture opening formed by the first and second apertures, and controls (adjusts) the amount of light passing through the aperture opening. In the following description, the amount of light passing through the aperture is also simply referred to as the aperture light intensity.

[0012] The lens control units 204 and 304 control the zoom motor and focus motor, respectively, in response to zoom and focus commands from the camera body 1 via the lens communication units 205 and 305. The lens control unit 204 also controls the aperture motor 105 in response to aperture commands from the camera body 1 via the lens communication unit 205.

[0013] The camera body 1 includes a first imaging element 12 that photoelectrically converts (images) a subject image formed by the first optical system 201, and a second imaging element 13 that photoelectrically converts a subject image formed by the second optical system 301. The first imaging element 12 and the second imaging element 13 are photoelectric conversion elements such as a CMOS sensor or a CCD sensor. The camera body 1 also has a camera control unit 14 that controls the driving of the first imaging element 12 and the second imaging element 13, and transmits various commands to the lens control units 204 and 304 via the camera communication units 15 and 16 and the lens communication units 205 and 305. An image processing unit (not shown) that performs various processes on the imaging signals from the first imaging element 12 and the second imaging element 13 to generate first image data and second image data is also provided in the camera control unit 14. By displaying the first image data and the second image data as a right-eye image and a left-eye image, respectively, on an observation device such as a monitor or a head-mounted display, the observer can observe a stereoscopic image.

[0014] In this embodiment, the camera body 1 having two imaging elements 12 and 13 for two optical systems 201 and 301 is shown. However, imaging signals for obtaining the first and second image data may be obtained in two regions on a single imaging element provided for the two optical systems.

[0015] FIG. 2 shows a specific configuration of the light amount control device 100. FIG. 3 shows the light amount control device 100 disassembled.

[0016] The light intensity control device 100 includes a first aperture for the first optical system 201, which includes a plurality (six in this embodiment) of aperture blades 104; a second aperture for the second optical system 301, which includes six aperture blades 104; and an opening / closing mechanism for driving the aperture blades 104 to open and close. The opening / closing mechanism includes an aperture motor 105 as a drive source, an aperture base plate 101 as a base member, and a first drive ring 102 as a first rotating member. The opening / closing mechanism also includes a second drive ring 112 as a second rotating member, a first cam plate 103 as a first retaining member, and a second cam plate 113 as a second retaining member. Furthermore, the opening / closing mechanism includes a first adjustment mechanism and a second adjustment mechanism. The first adjustment mechanism is composed of a first cam plate 103 and a first phase adjustment member 107, and the second adjustment mechanism is composed of a second cam plate 113 and a second phase adjustment member 117. The first and second adjustment mechanisms are mechanisms that allow the light intensity of at least one of the first and second apertures to be adjusted independently (individually) from the other.

[0017] The aperture motor 105 is a stepping motor, and a pinion gear 106, which acts as a drive gear, is fixed integrally to its rotary drive shaft 105a so as to be rotatable. The rotary drive shaft 105a is rotatably held by a bearing 105b. When the aperture motor 105 is fixed to the aperture base plate 101, the rotary drive shaft 105a is positioned in a predetermined position relative to the aperture base plate 101. The pinion gear 106 protrudes from a hole 101e formed in the aperture base plate 101 toward the first and second drive rings.

[0018] The aperture base plate 101 has a first aperture 101a corresponding to the first optical system 201 and a second aperture 101b corresponding to the second optical system 301. Multiple fitting receiving portions 101c are formed on the inner circumference of the first aperture 101a in the circumferential direction, and fitting portions 102a provided on the outer circumference of the first drive ring 102 are rotatably fitted into the multiple fitting receiving portions 101c. As a result, the first drive ring 102 is held rotatably relative to the aperture base plate 101 around the central axis of the first aperture 101a (i.e., around the optical axis OA1 of the first optical system 201). Multiple fitting receiving portions 101d are formed on the inner circumference of the second aperture 101b in the circumferential direction, and fitting portions 112a provided on the outer circumference of the second drive ring 112 are rotatably fitted into the multiple fitting receiving portions 101d. As a result, the second drive ring 112 is held rotatably around the central axis of the second aperture 101b (i.e., around the optical axis OA2 of the second optical system 301) relative to the aperture base plate 101.

[0019] Gear portions 102b and 112b are formed on parts of the outer circumference of the first drive ring 102 and the second drive ring 112, respectively, and the pinion gear 106 meshes with these gear portions 102b and 112b. Therefore, when the aperture motor 105 is driven and the pinion gear 106 rotates, the first drive ring 102 and the second drive ring 112 rotate in the same direction relative to the aperture base plate 101.

[0020] The first aperture is an iris diaphragm in which six aperture blades 104 are arranged at equal intervals in the circumferential direction of the first drive ring 102 such that some of them overlap in the optical axis direction, forming an aperture opening corresponding to the first optical system 201. The first drive ring 102 has six rotating holes 102c formed at equal intervals in the circumferential direction. The rotating pins 104a of the six aperture blades 104 are rotatably fitted into the corresponding rotating holes 102c of the first drive ring 102. The second aperture is an iris diaphragm in which six aperture blades 104 are arranged at equal intervals in the circumferential direction of the second drive ring 112 such that some of them overlap in the optical axis direction, forming an aperture opening corresponding to the second optical system 301. The second drive ring 112 has six rotating holes 112c formed at equal intervals in the circumferential direction. The rotating pins 104a of the six aperture blades 104 are rotatably fitted into the corresponding rotating holes 112c of the second drive ring 112.

[0021] Furthermore, the first and second apertures are not limited to those having six aperture blades; any iris diaphragm with three or more aperture blades will suffice.

[0022] The first cam plate 103 is positioned between the aperture base plate 101 and the first drive ring 102 and the six aperture blades 104 for the first aperture, and is fixed to the aperture base plate 101 by screws. The first cam plate 103 has a first opening 103a that corresponds to the first optical system 201. Six cam grooves 103c are formed around the first opening 103a on the first cam plate 103 at equal intervals in the circumferential direction. In the first aperture, the cam pins 104b of the six aperture blades 104 each engage with the corresponding cam groove 103c.

[0023] The second cam plate 113 is positioned between the aperture base plate 101 and the second drive ring 112 and the six aperture blades 104 for the second aperture, and is fixed to the aperture base plate 101 with screws. The second cam plate 113 has a second opening 113a that corresponds to the second optical system 301. Six cam grooves 113c are formed around the second opening 113a on the second cam plate 113 at equal intervals in the circumferential direction. In the second aperture, the cam pins 104b of the six aperture blades 104 each engage with the corresponding cam groove 113c.

[0024] With the above configuration, when the rotation of the aperture motor 105 causes each drive ring (102, 112) to rotate, the rotation pin 104a of each aperture blade 104 moves circumferentially together with each drive ring. At the same time, the cam pin 104b of each aperture blade 104 moves along the cam groove portions (103c, 113c) of each cam plate (103, 113), causing each aperture blade 104 to rotate (swivel) in the opening and closing direction around the rotation pin 104a. As a result, the diameter of the aperture opening (aperture value) formed by the six aperture blades 104 in each of the first and second apertures changes. The lens control unit 204 controls the driving direction of the aperture motor 105 (i.e., the direction of change of the aperture value) by changing the polarity of the drive pulse signal applied to the aperture motor 105, and controls the driving position of the aperture motor 105 (i.e., the aperture value) by counting the number of pulses of the drive pulse signal. A sensor may be provided to detect when each aperture is in the open aperture state.

[0025] In this embodiment, each drive ring (102, 112) is formed with a rotating hole (102c, 112c) into which the rotating pin 104a of each aperture blade engages, and each cam plate (103, 113) is formed with a cam groove (103c, 113c) into which the cam pin 104b of each aperture blade engages. However, each drive ring may be formed with a cam groove into which the cam pin of each aperture blade engages, and the retaining member corresponding to the cam plate may be formed with a rotating hole into which the rotating pin of each aperture blade engages.

[0026] A fitting portion 103b is provided on the outer circumference of the first cam plate 103. The fitting portion 103b rotatably fits into a fitting portion 101m provided on the inner circumference of the aperture base plate 101. As a result, the first cam plate 103 is held rotatably around the central axis of the first opening 101a of the aperture base plate 101. Furthermore, screw insertion portions 103e are provided at three locations in the circumferential direction on the outer circumference of the first cam plate 103. Each screw insertion portion 103e has an elongated hole shape that extends in the circumferential direction of the first cam plate 103. Screws inserted into each screw insertion portion 103e are tightened into screw holes provided around the first opening 101a of the aperture base plate 101. As a result, the first cam plate 103 is mounted to the aperture base plate 101 in a way that allows adjustment of its circumferential phase (rotational position) by the length of the elongated hole of each screw insertion portion 103e.

[0027] Furthermore, a part of the outer circumference of the first cam plate 103 is provided with an adjustment member receiving portion 103d. Inside the adjustment member receiving portion 103d, the first phase adjustment member 107 is positioned so as to abut against the inner surface of the adjustment member receiving portion 103d in the circumferential direction of the first cam plate 103. The first phase adjustment member 107 is rotatably attached to the aperture base plate 101 inside the adjustment member receiving portion 103d by tightening a screw inserted into the hole in the center of the first phase adjustment member 107 into the screw hole 101g of the aperture base plate 101. In this way, the first adjustment mechanism is configured.

[0028] A fitting portion 113b is provided on the outer circumference of the second cam plate 113. The fitting portion 113b rotatably fits into a fitting portion 101n provided on the inner circumference of the aperture base plate 101. As a result, the second cam plate 113 is held rotatably around the central axis of the second opening 101b of the aperture base plate 101. Furthermore, screw insertion portions 113e are provided at three locations in the circumferential direction on the outer circumference of the second cam plate 113. Each screw insertion portion 113e has an elongated hole shape that extends in the circumferential direction of the second cam plate 113. Screws inserted into each screw insertion portion 113e are tightened into screw holes provided around the second opening 101b of the aperture base plate 101. As a result, the second cam plate 113 is mounted to the aperture base plate 101 so as to be able to adjust its circumferential phase by the length of the elongated hole of each screw insertion portion 113e.

[0029] Furthermore, a portion of the outer circumference of the second cam plate 113 is provided with an adjustment member receiving portion 113d. Inside the adjustment member receiving portion 113d, a second phase adjustment member 117 is positioned so as to abut against the inner surface of the adjustment member receiving portion 113d in the circumferential direction of the second cam plate 113. The second phase adjustment member 117 is rotatably attached to the aperture base plate 101 inside the adjustment member receiving portion 113d by tightening a screw inserted into the hole in its center into a screw hole (not shown) in the aperture base plate 101. In this way, the second adjustment mechanism is configured.

[0030] Each cam plate (103, 113) may be rotatably attached to the aperture base plate 101 by a mounting structure other than the screw and slot mounting structure described above, for example, by a bayonet structure. In this embodiment, adjustment mechanisms are provided for both the first and second apertures, but adjustment mechanisms may be provided for only one of the first or second apertures.

[0031] Next, the operation of the first and second adjustment mechanisms will be explained using Figures 4(a) to 4(c). However, since the second adjustment mechanism has the same configuration as the first adjustment mechanism, only the operation of the first adjustment mechanism will be explained here. Figure 4(a) shows the light intensity control device 100 as viewed from the optical axis direction (the direction in which the central axes of apertures 101a and 101b extend). Figure 4(b) shows the first adjustment mechanism as viewed from the axial direction of the first phase adjustment member 107. Figure 4(c) shows an enlarged view of the cross-section along line AA in Figure 4(a).

[0032] As shown in Figure 4(c), the first phase adjustment member 107 is an eccentric member having a fitting portion 107b with axis x as its rotation center and a cylindrical eccentric surface 107a with axis y, which is eccentric to axis x, as its center. Axes x and y extend in directions perpendicular to the optical axis with respect to the light intensity control device 100. The eccentricity of axis y with respect to axis x is denoted as Δ. The fitting portion 107b is rotatably fitted and held around axis x in a concave fitting portion 101f provided on the aperture base plate 101. The eccentric surface 107a abuts against the inner surface of the adjustment member receiving portion 103d provided on the first cam plate 103 in the circumferential direction of the first cam plate 103.

[0033] The tip of the first phase adjustment member 107 is provided with a cleavage line portion 107c, and by engaging a jig such as a screwdriver with the cleavage line portion 107c, the first phase adjustment member 107 can be rotated around axis x. When the first phase adjustment member 107 rotates, the eccentric surface 107a pushes the inner surface of the adjustment member receiving portion 103d in the circumferential direction of the first cam plate 103. As a result, the first cam plate 103 rotates relative to the aperture base plate 101, with the screw insertion portion 103e guided by the screw. That is, the phase of the first cam plate 103 relative to the aperture base plate 101 changes. As a result, the relationship (relative phase) between the phase of the first drive ring 102 and the phase of the first cam plate 103 also changes. The phase of the first cam plate 103 corresponds to the rotational position of each aperture blade 104. Therefore, as the phase of the first cam plate 103 changes relative to the first drive ring 102, the rotational position of each aperture blade 104 relative to the phase of the first drive ring 102, that is, the aperture diameter of the first aperture, changes.

[0034] In this way, by rotating the first phase adjustment member 107, the aperture diameter of the first aperture (for example, the open aperture diameter) relative to the phase of the first drive ring 102 can be adjusted.

[0035] Figures 5(a) to 5(c) show the adjustment of the aperture diameter of the first aperture by rotating the first phase adjustment member 107. When the first phase adjustment member 107 is rotated clockwise in the left figure as shown in Figure 5(b) from the neutral state shown in Figure 5(a), the first cam plate 103 rotates counterclockwise in the right figure. The aperture diameter of the first aperture increases (i.e., the amount of light increases) according to the amount of rotation (phase change) of the first cam plate 103 at this time.

[0036] Furthermore, when the first phase adjustment member 107 is rotated counterclockwise in the left diagram as shown in Figure 5(c) from the neutral state shown in Figure 5(a), the first cam plate 103 rotates clockwise in the right diagram. The aperture diameter of the first aperture decreases (i.e., the amount of light decreases) according to the amount of phase change of the first cam plate 103 at this time.

[0037] By changing the eccentricity Δ of the first phase adjustment member 107, the amount of phase change of the first cam plate 103 in relation to the amount of rotation of the first phase adjustment member 107 (hereinafter also referred to as adjustment sensitivity) can be changed. Specifically, increasing the eccentricity Δ increases the amount of phase rotation of the first cam plate 103 in relation to the unit amount of rotation of the first phase adjustment member 107, and decreasing the eccentricity Δ decreases the amount of phase rotation of the first cam plate 103.

[0038] After adjusting the aperture diameter of the first aperture (for example, the open aperture diameter) as described above, the first cam plate 103 is bonded and fixed to the aperture base plate 101, or the first phase adjustment member 107 is bonded and fixed to the aperture base plate 101. However, in order to reduce the difference in light intensity between the first aperture and the second aperture during the actual use of the stereo optical unit 20, the first phase adjustment member 107 may be held rotatably without the above bonding.

[0039] Alternatively, the first phase adjustment member 107 may be configured by dividing it into a first portion coaxial with the axis x and a second portion eccentric with respect to the axis x, with the first portion rotatably attached to the aperture base plate 101 and the second portion in contact with the adjustment member receiving portion 103d of the first cam plate 103.

[0040] Figures 6(a) and 6(b) illustrate the effect of adjusting the aperture diameter of the first diaphragm to match that of the second diaphragm. Figures 6(a) and 6(b) show the relationship between the drive amount of the aperture motor 105 (number of drive pulses from open to closed = steps) and the amount of light. The horizontal axis represents the drive amount, and the vertical axis represents the amount of light.

[0041] In this embodiment, the first and second apertures use the same components as the first and second drive rings 102 and 112, the first and second cam plates 103 and 113, the aperture blades 104, and the first and second phase adjustment members 107 and 1117, respectively. This makes it possible to make the amount of change in the aperture opening diameter (the slope of the graph in the figure) with respect to the unit drive amount of the aperture motor 105 approximately the same.

[0042] Figure 6(a) shows the aperture diameter of the first aperture before adjustment. At this time, there is a difference in aperture diameter (i.e., light intensity) between the first and second apertures due to variations in manufacturing and assembly tolerances. In contrast, Figure 6(b) shows the state after adjusting the light intensity of the first aperture to match that of the second aperture. By adjusting the light intensity of the first aperture while comparing the light intensity of the first and second apertures, the difference in light intensity between the first and second apertures can be reduced. Alternatively, the aperture diameter of the second aperture may be adjusted to match the light intensity of the first aperture. [Examples]

[0043] Figure 7 shows the light intensity control device 100 of Example 2 as viewed from the optical axis direction. This example differs from Example 1 in the configuration of the first and second adjustment mechanisms. Other configurations are the same as in Example 1.

[0044] A gear portion 103f is provided on the outer circumference of the first cam plate 103. The gear portion 103f engages with a first adjustment gear 108, which is a rotational operating member rotatably supported on a shaft portion 101h provided on the aperture base plate 101. Therefore, when the first adjustment gear 108 is rotated around the shaft portion 101h, its rotation is reduced via the gear portion 103f and transmitted to the first cam plate 103. As a result, the first cam plate 103 rotates around the central axis of the opening 101a of the aperture base plate 101, and the phase of the first cam plate 103 with respect to the first drive ring 102 changes. The first adjustment mechanism is configured in this way.

[0045] On the other hand, a gear portion 113f is provided on the outer circumference of the second cam plate 113. A second adjustment gear 118, which acts as a rotational operating member, is rotatably supported on a shaft portion 101i provided on the aperture base plate 101, and meshes with the gear portion 113f. Therefore, when the second adjustment gear 118 is rotated around the shaft portion 101i, its rotation is reduced via the gear portion 103f and transmitted to the second cam plate 113. As a result, the second cam plate 113 rotates around the central axis of the opening 101b of the aperture base plate 101, and the phase of the second cam plate 113 with respect to the second drive ring 112 changes. The second adjustment mechanism is configured in this way.

[0046] The greater the reduction ratio of the gear sections 103f and 113f relative to the first and second adjustment gears 108 and 118, the lower the adjustment sensitivity can be.

[0047] In this embodiment, adjustment mechanisms are provided for both the first and second apertures, but adjustment mechanisms may be provided for only one of the first or second apertures.

[0048] Figures 8(a) to 8(c) show the adjustment of the aperture diameter of the first aperture by rotating the first adjustment gear 108. When the first adjustment gear 108 is rotated clockwise from the neutral position shown in Figure 8(a) to the position shown in Figure 8(b), the first cam plate 103 rotates counterclockwise. The aperture diameter of the first aperture increases (i.e., the amount of light increases) according to the amount of phase change of the first cam plate 103 at this time.

[0049] When the first adjustment gear 108 is rotated counterclockwise from the neutral position shown in Figure 8(a) as shown in Figure 8(c), the first cam plate 103 rotates clockwise. The aperture diameter of the first diaphragm decreases (i.e., the amount of light decreases) according to the amount of phase change of the first cam plate 103 at this time.

[0050] The first and second adjustment gears 108 and 118 may be removed after adjusting the aperture diameter of at least one of the first and second apertures as described above. Alternatively, at least one of the first and second adjustment gears 108 and 118 may be reattached to reduce the difference in light intensity between the first and second apertures that occurs during the actual use of the stereo optical unit 20.

[0051] Alternatively, instead of using individual adjustment gears to rotate the cam plate, a configuration in which a rotatable roller rotates the cam plate by friction may be adopted. [Examples]

[0052] Figure 9 shows the light intensity control device 100 of Example 3 as viewed from the optical axis direction. This example differs from Examples 1 and 2 in the configuration of the first and second adjustment mechanisms. Other configurations are the same as in Examples 1 and 2.

[0053] A connecting portion 103g is provided on the outer circumference of the first cam plate 103. The operating portion 109b, which is one end of the first adjustment lever 109, is engaged with the connecting portion 103g. The operating portion 109a, which is the other end of the first adjustment lever 109, is operated and the first adjustment lever 109 rotates around the shaft portion 101h (around the pivot point), and the rotation of the operating portion 109b (i.e., rotational force) is transmitted to the first cam plate 103 via the connecting portion 103g. As a result, the first cam plate 103 rotates around the central axis of the opening 101a of the aperture plate 101, and the phase of the first cam plate 103 with respect to the first drive ring 102 changes. The first adjustment mechanism is configured in this way.

[0054] On the other hand, a connecting portion 113g is provided on the outer circumference of the second cam plate 113. The operating portion 119b, which is one end of the second adjustment lever 119 that is rotatably supported on a shaft portion 101i provided on the aperture base plate 101, engages with the connecting portion 113g. When the operating portion 119a, which is the other end of the second adjustment lever 119, is operated and the second adjustment lever 119 rotates around the shaft portion 101i, the rotation (rotational force) of the operating portion 119b is transmitted to the second cam plate 113 via the connecting portion 113g. As a result, the second cam plate 113 rotates around the central axis of the opening 101b of the aperture base plate 101, and the phase of the second cam plate 113 with respect to the second drive ring 112 changes. The second adjustment mechanism is configured in this way.

[0055] In the first and second adjustment levers 109 and 119, the second length from the shafts 101h and 101i to the working parts 109b and 119b is set to be shorter than the first length from the operating parts 109a and 119a to the shafts 101h and 101i acting as pivot points. As a result, the amount of rotation of each working part, that is, the amount of rotation of each cam plate, is small relative to the amount of operation of each operating part. The smaller the ratio of the second length to the first length, the lower the adjustment sensitivity can be.

[0056] In this embodiment, adjustment mechanisms are provided for both the first and second apertures, but adjustment mechanisms may be provided for only one of the first or second apertures.

[0057] Figures 10(a) to 10(c) show the adjustment of the aperture diameter of the first aperture by rotating the first adjustment lever 109. When the first adjustment lever 109 is rotated clockwise from the neutral position shown in Figure 10(a) to the position shown in Figure 10(b), the first cam plate 103 rotates counterclockwise. The aperture diameter of the first aperture increases (i.e., the amount of light increases) according to the amount of phase change of the first cam plate 103 at this time.

[0058] When the first adjustment lever 109 is rotated counterclockwise from the neutral position shown in Figure 10(a) to the position shown in Figure 10(c), the first cam plate 103 rotates clockwise. The aperture diameter of the first diaphragm decreases (i.e., the amount of light decreases) according to the amount of phase change of the first cam plate 103 at this time.

[0059] The first and second adjustment levers 109 and 119 may be removed after adjusting the aperture diameter of at least one of the first and second apertures as described above. Alternatively, at least one of the first and second adjustment levers 109 and 119 may be reattached to reduce the difference in light intensity between the first and second apertures that occurs during the actual use of the stereo optical unit 20. [Examples]

[0060] Figure 11 shows the external appearance of the stereo optical unit 20 equipped with the light intensity control device 100 of Embodiment 1. Figure 12 shows a cross-section of the stereo optical unit 20 perpendicular to the optical axis.

[0061] The outer circumferential surface of the stereo optical unit 20 is provided with two adjustment holes (openings) 20a into which a jig 400, such as a driver, can be inserted to adjust the first and second phase adjustment members 107 and 117 of the light intensity control device 100 from the outside. The jig 400 inserted into the stereo optical unit 20 through the adjustment holes 20a can be engaged with the first and second phase adjustment members 107 and 117 and rotated. This allows the phase of the first and second cam plates 103 and 113 to be changed, and the aperture diameter (light intensity) of the first and second apertures to be adjusted, as shown in Figures 5(b) and (c).

[0062] Figures 13(a) and (b) illustrate the effect of adjusting the light intensity of the second aperture to match that of the first aperture. Figures 13(a) and (b) show the relationship between the drive amount of the aperture motor 105 (number of drive pulses from open to closed = steps) and the light intensity. The horizontal axis represents the drive amount, and the vertical axis represents the light intensity.

[0063] Figure 13(a) shows the state before adjusting the light intensity of the second aperture. At this time, there is a difference in the light intensity of the first and second apertures due to variations in manufacturing and assembly tolerances, as well as the difference in transmittance between the first and second optical systems 201 and 301, respectively. In contrast, Figure 13(b) shows the state after adjusting the light intensity of the second aperture to match the light intensity of the brighter first aperture. By adjusting the light intensity of the second aperture while comparing the light intensity passing through the first aperture and the light intensity passing through the second aperture, the difference in light intensity between the first and second apertures can be reduced. Alternatively, the light intensity of the first aperture may be adjusted to match the light intensity of the second aperture.

[0064] The adjustment mechanisms described in Embodiments 1 to 3 above are configured to adjust the phase of the cam plates (103, 113) relative to the drive rings (102, 112) which are rotating members, by rotating the cam plates (103, 113) which are holding members. Alternatively, an adjustment mechanism may be provided that adjusts the phase of the drive ring relative to the cam plates by rotating the drive ring. For example, an adjustment mechanism may be adopted in which the pinion gear (106) of the aperture motor (105) disengages from the drive ring to be adjusted, the drive ring is rotated to change the phase relative to the corresponding cam plate, and then the engagement is returned after the change. Alternatively, an idler gear may be provided between the pinion gear and the drive ring, and an adjustment mechanism may be adopted in which the idler gear disengages from the pinion gear or drive ring, the drive ring is rotated to change the phase relative to the corresponding cam plate, and then the engagement is returned after the change. Furthermore, the main body portion of the drive ring that holds the rotation pin (104a) of the aperture blades and the gear portion (102b, 112b) provided on the outer circumference of the main body portion are configured as separate parts. Furthermore, an adjustment mechanism may be employed to change the phase of the drive ring (main body) relative to the cam plate by rotating the main body relative to the gear while the gear is engaged with the pin-on gear, and then fixing the main body and gear after the change.

[0065] Furthermore, although the above embodiments described a case where two apertures are driven by a single drive source, the two apertures may also be driven by two drive sources (a first drive source and a second drive source) provided for each aperture. In this case, an adjustment mechanism can be provided that allows the amount of light passing through at least one of the first aperture and the second aperture to be adjusted independently of the amount of light passing through the other, without relying on the first and second drive sources.

[0066] The above embodiments include the following configuration.

[0067] (Composition 1) A light intensity control device that controls the amount of light in a first optical system and a second optical system arranged in parallel, A single power source, A first aperture, driven by the aforementioned drive source, which changes the amount of light in the first optical system, A second aperture, driven by the aforementioned drive source, which changes the amount of light in the second optical system, A light intensity control device characterized by having an adjustment mechanism that allows the amount of light passing through at least one of the first aperture and the second aperture to be adjusted independently of the amount of light passing through the other, without relying on the aforementioned drive source. (Configuration 2) The first aperture and the second aperture are each composed of a plurality of aperture blades, a holding member that holds the plurality of aperture blades, and a rotating member that drives the plurality of aperture blades by being rotated relative to the holding member by the drive source. The light intensity control device according to configuration 1, characterized in that the adjustment mechanism changes the relative phase between the holding member and the rotating member in at least one of the first aperture and the second aperture. (Composition 3) The light intensity control device according to configuration 2, characterized in that the adjustment mechanism changes the relative phase by receiving an operation from outside the light intensity control device. (Composition 4) The light intensity control device according to configuration 3, characterized in that the adjustment mechanism changes the phase of the holding member with respect to the rotating member by the operation of an eccentric member having an eccentric surface eccentric with respect to the rotation center. (Composition 5) The light intensity control device according to configuration 2, characterized in that the adjustment mechanism changes the phase of the holding member with respect to the rotating member by rotating the holding member via an operating member that receives the operation. (Composition 6) The aforementioned operating member is a member that is rotated, The light intensity control device according to configuration 5, characterized in that the operating member reduces its rotation and transmits it to the holding member. (Composition 7) The aforementioned operating member is a lever that rotates around a pivot point. The light intensity control device according to configuration 5, characterized in that the length from the pivot point to the part that transmits rotational force to the holding member is shorter than the length from the operating part to the pivot point of the lever. (Composition 8) A light intensity control device that controls the amount of light in a first optical system and a second optical system arranged in parallel, First drive source and The second power source and A first aperture driven by the first drive source to change the light intensity of the first optical system, A second aperture, driven by the aforementioned second drive source, which changes the amount of light in the aforementioned second optical system, A light intensity control device characterized by having an adjustment mechanism that allows the amount of light passing through at least one of the first aperture and the second aperture to be adjusted independently of the amount of light passing through the other, without relying on the first and second drive sources. (Composition 9) A light intensity control device described in any one of configurations 1 to 8, An optical instrument characterized by having the first and second optical systems described above. (Composition 10) The optical device according to configuration 9, characterized in that the optical device has an opening for operating the adjustment mechanism from the outside.

[0068] The embodiments described above are merely representative examples, and various modifications and changes can be made to each embodiment when implementing the present invention. [Explanation of Symbols]

[0069] 20 Stereo Optical Units 100 Light intensity control device 102,112 drive ring 103,113 Cam plate 107,117 Phase adjustment member 108,118 Adjustment Gear 109,119 Adjustment lever

Claims

1. A light intensity control device that controls the amount of light in a first optical system and a second optical system arranged in parallel, A single power source, A first aperture driven by the aforementioned drive source to change the amount of light in the first optical system, A second aperture, driven by the aforementioned drive source, which changes the amount of light in the second optical system, A light intensity control device characterized by having an adjustment mechanism that allows the amount of light passing through at least one of the first aperture and the second aperture to be adjusted independently of the amount of light passing through the other, without relying on the aforementioned drive source.

2. The first aperture and the second aperture are each composed of a plurality of aperture blades, a holding member that holds the plurality of aperture blades, and a rotating member that drives the plurality of aperture blades by being rotated relative to the holding member by the drive source. The light intensity control device according to claim 1, characterized in that the adjustment mechanism changes the relative phase between the holding member and the rotating member in at least one of the first aperture and the second aperture.

3. The light intensity control device according to claim 2, characterized in that the adjustment mechanism changes the relative phase by receiving an operation from outside the light intensity control device.

4. The light intensity control device according to claim 3, characterized in that the adjustment mechanism changes the phase of the holding member with respect to the rotating member by the operation of an eccentric member having an eccentric surface eccentric with respect to the rotation center.

5. The light intensity control device according to claim 2, characterized in that the adjustment mechanism changes the phase of the holding member with respect to the rotating member by rotating the holding member via the operating member that receives the operation.

6. The aforementioned operating member is a member that is rotated, The light intensity control device according to claim 5, characterized in that the operating member reduces its rotation and transmits it to the holding member.

7. The aforementioned operating member is a lever that rotates around a pivot point. The light intensity control device according to claim 5, characterized in that the length from the pivot point to the part that transmits rotational force to the holding member is shorter than the length from the operating part to the pivot point of the lever.

8. A light intensity control device that controls the amount of light in a first optical system and a second optical system arranged in parallel, First drive source and The second drive source and A first aperture driven by the first drive source to change the light intensity of the first optical system, A second aperture, driven by the second drive source, which changes the amount of light in the second optical system, A light intensity control device characterized by having an adjustment mechanism that allows the amount of light passing through at least one of the first aperture and the second aperture to be adjusted independently of the amount of light passing through the other, without relying on the first and second drive sources.

9. A light intensity control device according to any one of claims 1 to 8, An optical instrument characterized by having the first and second optical systems described above.

10. The optical device according to claim 9, characterized in that the optical device has an opening for operating the adjustment mechanism from the outside.

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