Light control device

Abstract

To provide an optical control device that can change an irradiation direction of light with which an object is irradiated without changing the position of an optical system.SOLUTION: An optical control device comprises: a light source; a light condensing unit; and an optical route control unit. The light source emits light. The light condensing unit condenses the light the light source emits to irradiate an object with the condensed light. The optical route control unit is arranged between the light source and the light condensing unit, and changes an irradiation direction of the light relative to the object by changing the position of a portion where the light passes in a plane vertical to an optical axis of the light.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a technique for irradiating an object with light. [Background technology]

[0002] A subject may be photographed using a camera while illuminating the subject through a transparent or translucent medium such as glass. In this case, the direct reflection of the illumination light from the surface of the transparent object enters the camera, resulting in the captured image containing not only the reflected light from the subject but also the reflected light from the transparent object's surface. If the direct reflection of the illumination light from the surface of the transparent object enters the camera, the pixel values ​​of the captured image become saturated, making it impossible to accurately observe the reflectance and shape of the subject. Therefore, to photograph a subject without pixel value saturation due to direct reflection from the surface of the transparent object, a camera with a wide dynamic range must be used, or the relative positions of the illumination light, camera, and transparent object must be changed depending on the shape of the transparent object so that the direct reflection of the illumination light does not enter the camera. However, cameras with a wide dynamic range that do not saturate even with the direct reflection of the illumination light do not generally exist. Therefore, to prevent saturation in the captured image, it is necessary to control the direction of light illumination on the transparent object and the subject.

[0003] Patent document 1 describes a method for changing the angle of the optical axis of illumination light focused on a sample by adjusting the position of an aperture included in an illumination optical system in an observation device that irradiates illumination light onto a sample. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-147739 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the technique of Patent Document 1 has a structure in which the diaphragm is moved in the direction of the optical axis of the illumination light, and therefore requires securing an area for moving the diaphragm, which results in the problem of an increased size of the device.

[0006] An object of the present invention is to provide a light control device that can change the direction of light irradiated onto an object without changing the position of the optical system. [Means for solving the problem]

[0007] In one aspect of the present invention, a light control device includes: A half-moon shaped opening is provided as a light blocking means for blocking part of the path of light emitted from the light source. The half-moon shaped openings are disposed at positions facing each other, and the openings form a portion through which light passes. a focusing means having a first plate and a second plate, which focuses the light that has passed through the light blocking means and irradiates the light onto an object; an optical path control means for changing the light blocking range of the light and the irradiation direction of the light with respect to the object by moving the first plate and the second plate so as to change the position of the portion of the light blocking means through which the light passes within a plane perpendicular to the optical axis of the light; Equipped with. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a light control device that can change the direction of light that is irradiated onto an object without changing the position of the optical system. [Brief explanation of the drawings]

[0009] [Figure 1] 1 shows the configuration of a light control device according to a first embodiment. [Figure 2] 1 shows an example of a light blocking portion. [Figure 3] 3 shows the direction of light irradiation by the light-shielding part in FIG. 2. [Figure 4] 10 shows another example of the light blocking portion. [Figure 5] 4 shows the direction of light irradiation by the light-shielding part in FIG. 3. [Figure 6] 10 is a flowchart showing the operation of the light control device. [Figure 7] 1 shows the configuration of a first modified example of the light control device. [Figure 8] 10 shows the configuration of a second modified example of the light control device. [Figure 9] 10 is a flowchart of the operation of a light control device according to a second modified example. [Figure 10] 1 shows the configuration of an imaging device to which a light control device is applied. [Figure 11] An example in which reflected light is directly incident on the imaging device is shown. [Figure 12] The configuration of a 3D shape estimation device that uses a light control device is shown. [Figure 13] 10 shows the configuration of a light control device according to a fourth embodiment. [Figure 14] 10 shows the configuration of a light blocking section according to Modification 1. [Figure 15] 10 shows the configuration of a light blocking section according to Modification 2. [Figure 16] 13 shows the configuration of a light blocking section according to Modification 3. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. [First embodiment] FIG. 1(A) shows the configuration of a light control device according to a first embodiment of the present invention. As shown in the figure, the light control device 10 includes a light source 11, a condenser 12, a light blocking unit 13, and a light path control unit 19. The light source 11 emits light toward the condenser 12. The light source 11 may be a point light source, a surface light source, a ring-shaped light source, or a parallel light source, and is not limited to a specific light source shape. In the example of FIG. 1(A), the light source 11 emits light L in the direction of the condenser 12.

[0011] The light collecting unit 12 collects the light L emitted from the light source 11 and irradiates the object X with the collected light as illumination light. The light collecting unit 12 is configured with a lens and has a light path control function using the light blocking unit 13. The light path control function controls the irradiation direction of the light irradiated onto the object X by blocking part of the path of the light L when the light collecting unit 12 collects the light L. Specifically, the light path control function is realized by the light path control unit 19. For example, the light path control unit 19 drives a motor that controls the lens aperture, which is an example of the light blocking unit 13, by having the processor execute a computer program. As a result, part of the path of the light from the light source 11 is blocked by the light blocking unit 13, and the path of the light changes.

[0012] The position where the light blocking unit 13 blocks the path of the light L may be the position of the aperture of the light collecting unit 12, which is a lens, or the light entrance or exit portion of the light collecting unit 12. The light blocking unit 13 may block the path of the light L by using the aperture of the light collecting unit 12, or by using a light blocking plate or film with an opening. In the example of FIG. 1(A), the light L emitted from the light source 11 is collected by the light collecting unit 12 and irradiated onto the object X. At this time, the light path control unit 19 controls the light blocking unit 13 so that the light L can be irradiated onto the object X from an irradiation direction D1 or an irradiation direction D2. Note that while two light beams L are shown in FIG. 1(A), this does not mean that the two light beams L pass through the light collecting unit 12 simultaneously; rather, it merely illustrates the manner in which the light blocking unit 13, which is movable in a plane perpendicular to the optical axis, passes the light L at different positions.

[0013] FIG. 1B shows the light control device 10 housed in a housing. The light source 11 and the condenser 12 of the light control device 10 are fixed inside the housing 14. In the example of FIG. 1B, the light source 11 is fixed to the housing 14 by a support 15, and the condenser 12 is fixed to the housing 14 by a support 16. The condenser 12 and the shading 13 are fixedly disposed, and their relative positions to the light source 11 are fixed. As described above, the light control device 10 changes the irradiation direction of light irradiated onto the object X by changing the path of light L using the light path control function using the shading 13. Therefore, there is no need to change the positions of the light source 11 and the condenser 12 themselves, and therefore the light source 11 and the condenser 12 can be fixedly disposed in the housing 14, as shown in FIG. 1A, thereby reducing the overall size of the device. In the above example, the light-collecting unit 12 and the light-shielding unit 13 are fixedly arranged, but if the light-shielding unit 13, which is controlled by the optical path control function, is configured to change the light passage position within a plane perpendicular to the optical axis of the light, the light-collecting unit 12 and the light-shielding unit 13 do not need to be fixedly arranged.

[0014] Next, a method for changing the illumination direction by blocking the light path with the light blocking unit 13 will be specifically described. In the following example, a lens is used as the light collecting unit 12, and the lens aperture is used as the light blocking unit 13. FIG. 2 shows the shape of the aperture when a typical lens aperture is narrowed. When a typical lens is used as the light collecting unit 12 and the light path is blocked using the lens aperture as the light blocking unit 13a, the direction of light irradiation onto the object X, i.e., the virtual light source direction as seen from the object X, is toward the center of the lens, and light is irradiated from the center of the lens to the object X, as shown by arrow D3 in FIG. 3.

[0015] On the other hand, when a lens aperture as shown in FIG. 4 is used as the light blocking unit 13b to block the light path, the virtual light source direction is located higher than in the case of FIG. 3, and light is irradiated from the top of the lens to the object X, as indicated by arrow D4 in FIG. 5. Therefore, by controlling the lens aperture as the light blocking unit 13b, the direction of light irradiated to the object X, i.e., the virtual light source direction, can be changed. Furthermore, if a lens aperture as shown in FIG. 4 is used as the light blocking unit 13b and the lens is made rotatable in the circumferential direction as indicated by arrow 71 in FIG. 4, the opening 13x formed by the aperture can be positioned at any position in the circumferential direction of the lens. This allows light to be irradiated to the object X from directions offset up, down, left, or right with respect to the optical axis direction that passes through the center of the lens and reaches the object X. Note that the function of rotating the lens in the circumferential direction can be achieved by, for example, configuring the support unit 16 shown in FIG. 1(B) to support the lens, which is the light collecting unit 12, so that it can rotate around its central axis. In this way, when a lens is used as the light collecting unit 12 and its aperture is used as the light blocking unit 13, the position of the light passing through the light collecting unit 12 can be changed by adjusting the position of the lens aperture. Also, the shape of the light passing through the light collecting unit 12 can be changed by adjusting the aperture of the lens, i.e., the shape of the opening 13x.

[0016] As the light-shielding unit 13, in addition to using a lens diaphragm as described above, a light-shielding plate or film with an opening can be used. In this case, the position through which light passes can be changed by moving the light-shielding plate or film with the opening to change the position of the opening. For example, as in the example of the diaphragm shown in FIG. 4, if an opening is provided in part of a disk-shaped light-shielding plate or film and the light-shielding plate or film is rotated in the circumferential direction, the position of the opening, i.e., the position through which light passes, moves in the circumferential direction relative to the optical axis. This allows the direction of light irradiation on the object X to be changed.

[0017] Furthermore, a liquid crystal (Liquid Crystal Display) element, a digital micromirror device, or the like can be used as the light blocking unit 13. In this case, the liquid crystal element or the digital micromirror device controls the path of the light by changing the polarization direction or path of the light emitted from the light source 11. This makes it possible to change the irradiation direction of the light on the object X.

[0018] 6 is a flowchart showing the operation of the light control device 10 of the first embodiment. First, as a light source light emission process, the light control device 10 causes the light source 11 to emit light and causes the light to enter the light collecting unit 12 (step S11). Next, as a light refraction process, the light collecting unit 12 refracts the light that has entered the light collecting unit 12 from the light source 11 toward the light blocking unit 13 (step S12).

[0019] Next, as an optical path control process, the position and shape of the light blocking unit 13 provided in the light collecting unit 12, specifically, the aperture provided in the lens, is changed to block light that passes through a specific path among the light that has entered the light blocking unit 13 (step S13). Light whose path is not blocked by the light blocking unit 13 passes directly through the light collecting unit 12. Note that, for convenience of explanation, an example in which a lens aperture is used as the light blocking unit 13 is shown here, but instead, a light blocking plate or film with an opening, a liquid crystal element, a digital micromirror device, or the like may be used as the light blocking unit 13.

[0020] Next, as a light collection process, the light collecting unit 12 collects the light that has passed through without being blocked by the light blocking unit 13 onto the focal plane of the light collecting unit 12, and irradiates the light onto the object X (step S14). As a result, the light is irradiated onto the object X in a direction from the position where the light blocking unit 13 has passed the light toward the object X.

[0021] According to the light control device 10, the light path control function can virtually change the light source position by controlling the light path within the lens that collects the light, without physically changing the position of the light source. This eliminates the need to install multiple lights to avoid the effect of direct reflection of the irradiated light on the surface of the object, and allows for the miniaturization of an imaging device using the light control device as lighting. Furthermore, even in cases where it is necessary to photograph an object by irradiating it with light from different light source directions, such as in photometric stereo, a single light source can be used to irradiate the object with light from different directions without changing the position of the light source, allowing for the miniaturization of an imaging device.

[0022] (First Modification of Light Control Device) 7 shows the configuration of a first modified example of the light control device. In the light control device 10x according to the first modified example, the condensing unit 12 is configured with two lenses 12a and 12b, with the shading unit 13 provided between them. As described above, the shading unit 13 can be a light-shielding plate or film with an opening, a liquid crystal element, a digital micromirror device, or the like. Furthermore, the light control device 10x is configured such that a relay lens 17 is provided after the condensing unit 12 to extend the optical path of the light irradiating the object X.

[0023] (Second Modification of Light Control Device) Fig. 8 shows the configuration of a second modified example of the light control device. The light control device 10y according to the second modified example includes a light reflecting unit 18 in addition to the configuration of the light control device 10 shown in Fig. 1(A). Note that the configuration of the light control device 10y is the same as that of the light control device 10 shown in Fig. 1 except for the light reflecting unit 18.

[0024] The light reflecting unit 18 reflects the light emitted by the light source 11 toward the light collecting unit 12. The light reflecting unit 18 is configured with a mirror, a digital micromirror device, or a combination of these. By using a digital micromirror device, even if the light source 11 itself cannot emit light with a spatial pattern, the light reflecting unit 18 can reflect the light with a spatial pattern, and the object X can be irradiated with the light with a spatial pattern. Note that there are no particular limitations on the method of reflecting light by the light reflecting unit 18, and the light may be reflected by a flat surface or a curved surface. As a specific example, the light reflecting unit 18 may reflect the reflected light so that it becomes parallel light. Note that in FIG. 8, the light collecting unit 12 and the light blocking unit 13 are integrated, but the light blocking unit 13 may be independent from the light collecting unit 12. Specifically, the light blocking unit 13 may be located either behind or in front of the light collecting unit 12 as viewed from the object X.

[0025] 9 is a flowchart of the operation of the light control device 10y according to the second modified example. First, the light control device 10y causes the light source 11 to emit light as a light source light emission process, causing the light to enter the light reflecting unit 18 (step S21). As a light reflection process, the light reflecting unit 18 reflects the light emitted by the light source 11 and causes the light to enter the light collecting unit 12 (step S22). Next, as a light refraction process, the light collecting unit 12 refracts the light that has entered the light collecting unit 12 from the light reflecting unit 18 toward the light blocking unit 13 (step S23).

[0026] Next, as a light path control process, the position and shape of an aperture serving as the light blocking unit 13 provided in the light collecting unit 12 are changed to block light that passes through a specific path among the light that has entered the light blocking unit 13 (step S24). Light whose path is not blocked by the light blocking unit 13 passes through the light collecting unit 12 as is. Then, as a light collecting process, the light collecting unit 12 collects the light that has passed through without being blocked by the light blocking unit 13 onto the focal plane of the light collecting unit 12, and irradiates the light onto the object X (step S25). As a result, the light is irradiated onto the object X in a direction from the position where the light blocking unit 13 transmitted the light toward the object X.

[0027] [Second embodiment] Next, a second embodiment to which the light control device of the first embodiment is applied will be described. In the second embodiment, the light control device is applied to an imaging device that captures an image of a subject. FIG. 10 shows the configuration of an imaging device to which the light control device 10 of the first embodiment is applied. In addition to the light control device 10, the imaging device 20 includes an image capture device 21 and a reflection determination unit 22. When capturing an image of a subject 50 through a semitransparent reflective object 51, the imaging device 20 prevents saturation of pixel values ​​of the captured image caused by light from the light source 11 being reflected by the semitransparent reflective object 51.

[0028] Generally, when photographing a subject 50 through a semitransparent reflective object 51, such as glass, through which light is partially transmitted, a portion of the light emitted from the light source 11 is reflected by the surface of the semitransparent reflective object 51. In this specification, an object that transmits and reflects a portion of light, such as glass, is referred to as a "semitransparent reflective object." As shown in FIG. 11 , if the imaging device 21 is located in the direction of the light reflected by the semitransparent reflective object 51, the reflected light directly enters the imaging device 21, resulting in saturation of the brightness value of the reflected light area in the captured image (also referred to as "overexposed highlights"). Therefore, in the second embodiment, the direction of light irradiated toward the semitransparent reflective object 51 is changed by the light blocking unit 13, thereby preventing the reflected light from the semitransparent reflective object 51 from directly entering the imaging device 21. This prevents overexposed highlights in the image captured by the imaging device 21, which are caused by the direct incidence of reflected light.

[0029] 10, when the light control device 10 irradiates the subject 50 with light L along irradiation direction D1, the light L is reflected by the semitransparent reflective object 51, and the reflected light travels along path R1 and directly enters the imaging device 21. On the other hand, when the light control device 10 irradiates the subject 50 with light L along irradiation direction D2, the light L is reflected by the semitransparent reflective object 51, but the reflected light travels along path R2 and does not directly enter the imaging device 21. Therefore, the light control device 10 controls the light path control unit 19 so that the reflected light does not directly enter the imaging device 21.

[0030] Specifically, the photographing device 20 operates as follows. The light control device 10 focuses light emitted from the light source 11 using the focusing unit 12 and irradiates the light onto the subject 50. The photographing device 21 captures an image of the subject 50 through a semi-transparent reflective object 51 and outputs the captured image to the reflection determination unit 22. The reflection determination unit 22 determines whether or not the input photographed image has undergone overexposure due to the reflection of light from the light source. For example, the reflection determination unit 22 compares the brightness value of each pixel in the photographed image with a predetermined threshold, and determines that overexposure has occurred in pixels whose brightness value is equal to or greater than the predetermined threshold. If overexposure has not occurred, the reflection determination unit 22 outputs the photographed image to the outside.

[0031] On the other hand, if blown-out highlights have occurred in the captured image, the reflection determination unit 22 controls the light path control unit 19 to change the path of light from the light source. For example, if the light blocking unit 13 is a lens diaphragm as described above, the light path control unit 19 controls the light blocking unit 13 to change the position of the opening of the lens diaphragm. This changes the direction in which light emitted from the light control device 10 is irradiated onto the subject 50. In this way, when the reflection determination unit 22 determines that blown-out highlights have occurred in the captured image, a captured image without blown-out highlights can be obtained by changing the direction in which light is irradiated onto the subject.

[0032] 10, as described above, when the light control device 10 emits light L along irradiation direction D1, the light reflected by the semi-transparent reflective object 51 directly enters the image capture device 21. Therefore, when the reflection determination unit 22 determines that blown-out highlights have occurred in the captured image input from the image capture device 21, it instructs the light control device 10 to change the path of the light. The light control device 10 controls the light path control unit 19 so that the light L is emitted along irradiation direction D2. In this way, the light reflected by the semi-transparent reflective object 51 will not directly enter the image capture device 21, and therefore blown-out highlights will not occur in the image captured by the image capture device 21.

[0033] Generally, to prevent overexposure in a captured image illuminated by light from a light source, it is necessary to change the position of at least one of the light source and the image capture device so that reflected light does not directly enter the image capture device. However, providing an image capture device with a mechanism for adjusting the position of the light source or the image capture device has the disadvantage of increasing the system size. In contrast, the image capture device 20 of the second embodiment can virtually change the light source position by changing the direction of light irradiation on the subject without physically moving the light control device 10 or the image capture device 21, thereby enabling the image capture device to be made more compact.

[0034] In the example of the photographing device 20 shown in FIG. 10, the light control device 10 of the first embodiment is used, but instead, the light control device 10x according to the first modified example or the light control device 10y according to the second modified example described above may be used.

[0035] [Third embodiment] Next, a third embodiment will be described, in which the light control device of the first embodiment is applied. In the third embodiment, the light control device is applied to a three-dimensional shape estimation device that estimates the three-dimensional shape of a subject. FIG. 12 shows the configuration of a three-dimensional shape estimation device that applies the light control device 10 of the first embodiment. The three-dimensional shape estimation device 30 includes a light source direction counting unit 31, an imaging device 32, and a three-dimensional shape estimation unit 33 in addition to the light control device 10 of the first embodiment.

[0036] Photometric stereo is a known method for estimating the three-dimensional shape of a subject using images captured from a single viewpoint by illuminating the subject with light from multiple different directions. This method allows the three-dimensional shape of the subject to be estimated based on images captured from a single viewpoint by changing the direction of the light source illuminating the subject. The three-dimensional shape estimation device 30 of the third embodiment uses the light control device 10 of the first embodiment to estimate the three-dimensional shape of the subject without changing the positions of either the imaging device or the light source.

[0037] The operation of the three-dimensional shape estimation device 30 will be described with reference to FIG. 12. In FIG. 12, the imaging device 32 receives the light source direction count number from the light source direction count unit 31 and compares the light source direction count number with a predetermined number N. Here, the "light source direction" refers to the direction of light emitted by the light control device 10 onto the subject 50, and the "light source direction count number" refers to the number of different illumination directions. The predetermined number "N" is the number of light source directions required to estimate the three-dimensional shape of the subject in photometric stereo. It is generally three or more when the light source direction is known and six or more when the light source direction is unknown. However, the method for estimating the three-dimensional shape of the subject is not limited to a specific photometric stereo method. Accordingly, the predetermined number N of the light source direction count number also varies depending on the three-dimensional shape estimation method.

[0038] When the count number of light source directions is less than the predetermined number N, the imaging device 32 photographs the subject 50 and stores the photographed image, and outputs a notification indicating that the image has been photographed (hereinafter also referred to as a "photography completion notification") to the light source direction counting unit 31. Here, the method for storing the photographed image is not limited to a specific method, and for example, the photographed image may be saved in an external storage medium. On the other hand, when the count number of light source directions is equal to or greater than the predetermined number N, the required number of photographs have been taken, so the imaging device 32 outputs all of the images previously photographed to the 3D shape estimation unit 33.

[0039] The light source direction counting unit 31 increments the light source direction count number by 1 each time an image capture completion notification is input from the imaging device 32, and outputs the light source direction count number to the imaging device 32. Furthermore, if the light source direction count number is less than a predetermined number N, the light source direction counting unit 31 outputs an instruction to change the light path to the light path control unit 19 of the light control device 10. As a result, the light path control unit 19 controls the light blocking unit 13 to change the irradiation direction of the light irradiated onto the subject, i.e., the light source direction.

[0040] For example, if the preset number N of light source direction counts is "3," light source direction counting unit 31 photographs the subject while changing the light source direction until the light source direction count reaches "3." As a result, photographs are taken of subject 50 with light irradiated from three different light source directions. Then, once the imaging device 32 has obtained photographed images corresponding to the three different light source directions, it supplies these to three-dimensional shape estimation unit 33. 3D shape estimation unit 33 estimates the three-dimensional shape of subject 50 using these photographed images and outputs a three-dimensional shape estimation map.

[0041] There is no particular limitation on the communication method between the light source direction counting unit 31 and the imaging device 32. Furthermore, there is no particular limitation on the communication method between the light source direction counting unit 31 and the light path control unit 19.

[0042] Photometric stereo estimates the 3D shape of an object based on images captured from a single viewpoint by changing the direction of a light source illuminating the object. This typically requires capturing images of the object while changing the light source direction, which requires either using multiple light sources or physically changing the light source's position. Using multiple light sources or changing the light source's position increases the size of the imaging device. Furthermore, physically moving the light source increases the imaging time by the time required for the movement. In this regard, the 3D shape estimation device 30 of the third embodiment uses a single light source to illuminate the object from multiple different directions, without physically moving the light source, and can estimate the 3D shape of the object from multiple images captured from a single viewpoint.

[0043] In the example of the photographing device 20 shown in FIG. 10, the light control device 10 of the first embodiment is used, but instead, the light control device 10x according to the first modified example or the light control device 10y according to the second modified example described above may be used.

[0044] [Fourth embodiment] Next, a fourth embodiment of the present invention will be described. Fig. 13 shows the configuration of a light control device according to the fourth embodiment. The light control device 60 includes a light source 61, a light collecting unit 62, and a light path control unit 63. The light source 61 emits light. The light collecting unit 62 collects the light emitted by the light source and irradiates the light onto an object. The light path control unit 63 is disposed between the light source 61 and the light collecting unit 62, and changes the position of the portion through which the light passes within a plane perpendicular to the optical axis, thereby changing the direction of irradiation of the light onto the object.

[0045] [Variations] The light blocking section controlled by the light path control section may be configured as in the following modified example. (Variation 1) FIG. 14 shows the configuration of the light blocking unit 70 according to the first modification. FIG. 14 is a plan view of the light blocking unit 70 as viewed from the light source side. The light blocking unit 70 is configured by a pair of crescent-shaped cutout plates 71a and 71b facing each other. The plates 71a and 71b are movable in the directions of the arrows, and the movement of the plates 71a and 71b is controlled by the light path control unit 19. FIG. 14(A) shows a state in which the plates 71a and 71b do not overlap. The crescent-shaped cutout portions of the plates 71a and 71b form openings 72 through which light passes. FIG. 14(B) shows a state in which the plates 71a and 71b have each moved in the directions of the arrows. As the plates 71a and 71b move in the directions of the arrows, the openings 72 become smaller, and the area through which light passes through the light blocking unit 70 becomes narrower. In the example of Fig. 14, the two plates 71a and 71b are arranged side by side in the left-right direction, but they may also be arranged side by side in the vertical direction and configured so that each plate can move up and down. Also, in the example of Fig. 14, the half-moon-shaped notches of plates 71a and 71b are located in the center in the vertical direction, but if the half-moon-shaped notches are formed to be shifted in the vertical direction in the figure, the position through which light passes can be shifted in the vertical direction.

[0046] (Variation 2) FIG. 15 shows the configuration of a light-shielding unit 80 according to Modification 2. FIG. 15 is a plan view of the light-shielding unit 80 as viewed from the light source side. The light-shielding unit 80 has a roll-shaped member 82 with a slit 82x formed therein. By winding the roll-shaped member 82 with a pair of winding units 81a and 81b, the position of the slit 82x moves, and the portion that transmits light moves. The winding of the roll-shaped member 82 is controlled by the light path control unit 19. The roll-shaped member 82 is made of paper, film, or the like. The slit 82x may be an opening or a transparent film, for example.

[0047] (Variation 3) FIG. 16 shows the configuration of a light blocking unit 90 according to Modification 3. FIG. 16 is a plan view of the light blocking unit 90 as viewed from the light source side. The light blocking unit 90 is configured by forming a plurality of holes 92 in a plate-like member 91 and providing shutter mechanisms at the locations of the holes 92. The shutter mechanism opens and closes in the direction of arrow 93. Light passes through the positions of the holes 92 when the shutter mechanism is in the open state. In the example of FIG. 16, only hole 92x is open. The position through which light passes is changed by controlling the positions of the holes 92 that the light path control unit 19 opens. Note that instead of the shutter mechanism, a light blocking member may be disposed on the back side of the holes 92, and the holes 92 may be opened and closed by moving the position of the light blocking member relative to the holes 92.

[0048] Some or all of the above-described embodiments can be described as, but are not limited to, the following supplementary notes.

[0049] (Appendix 1) A light source that emits light; a light collecting unit that collects light emitted from the light source and irradiates the light onto an object; a light path control unit that is disposed between the light source and the light collecting unit and that changes the position of a portion through which the light passes within a plane perpendicular to an optical axis of the light, thereby changing the irradiation direction of the light with respect to the object; A light control device comprising:

[0050] (Appendix 2) 2. The light control device according to claim 1, wherein the light path control section changes the shape of a portion through which the light passes.

[0051] (Appendix 3) 3. The light control device according to claim 1, wherein the light collecting unit is a lens, and the light path control unit controls an aperture of the lens.

[0052] (Appendix 4) 3. The light control device according to claim 1, wherein the light condensing unit is a lens, and the light path control unit controls a liquid crystal element or a micromirror device through which the light passes.

[0053] (Appendix 5) 5. The light control device according to claim 1, wherein the light source and the light collecting unit are fixed inside a housing.

[0054] (Appendix 6) A light control device according to any one of Supplementary Notes 1 to 5; an imaging device that captures an image of the object; a determination unit that changes the irradiation direction of the light using the light path control unit when saturation of pixel values ​​occurs in the image captured by the imaging device; An imaging device comprising:

[0055] (Appendix 7) A light control device according to any one of Supplementary Notes 1 to 5; a counting unit that counts the number of different irradiation directions of light onto the object; an imaging device that photographs the object while changing the irradiation direction of the light until the number of different irradiation directions of the light reaches a predetermined number; an estimation unit that acquires captured images corresponding to the predetermined number from the imaging device and estimates a three-dimensional shape of the object based on the captured images; A three-dimensional shape estimation device comprising:

[0056] (Appendix 8) Light is emitted from the light source, A light control method in which the position of the part through which the light passes is changed in a plane perpendicular to the optical axis of the light at a position between the light source and the focusing unit, thereby focusing the light and irradiating it onto the object while changing the irradiation direction toward the object.

[0057] (Appendix 9) A light control device that is arranged between a light source and a focusing unit and changes the direction of light irradiation onto an object by changing the position of the part through which the light passes within a plane perpendicular to the optical axis of the light.

[0058] Although the present invention has been described above with reference to the embodiments and examples, the present invention is not limited to the above-described embodiments and examples. Various modifications that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention. [Explanation of symbols]

[0059] 10, 10x, 10y light control device 11 Light source 12 Light collecting part 13 Light blocking section 18 Light reflecting part 19 Optical path control unit 20 Imaging equipment 21 Imaging device 22 Reflection judgment section 30 3D shape estimation device 31 Light source direction counting unit 32 Imaging device 33 3D shape estimation section

Claims

1. a light-blocking means for blocking a part of the path of light emitted from the light source, the light-blocking means including a first plate and a second plate having a crescent-shaped opening and being disposed at positions where the crescent-shaped opening faces each other, the first plate and the second plate forming a part through which the light passes by the opening, the light-blocking means for collecting the light that has passed through the light-blocking means and irradiating the object with the light; an optical path control means for changing the light blocking range of the light and the irradiation direction of the light with respect to the object by moving the first plate and the second plate so as to change the position of the portion of the light blocking means through which the light passes within a plane perpendicular to the optical axis of the light; A light control device comprising:

2. Further having a housing, 2. The light control device according to claim 1, wherein the light source, the light condensing means, and the light path control means are provided inside the housing.

3. The light control device according to claim 2 , wherein the light source and the light collecting means are fixed inside the housing.

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