JP2009204734A - Method for adjusting light distribution, illuminator and imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide: a method for adjusting light distribution; an illuminator; and an imaging apparatus. <P>SOLUTION: Before regular light emission by a strobe light source 14, preliminary light emission is performed in a state that maximum transmittance is set to all the liquid crystal elements forming a light distribution changing part 15, and an illumination range under the preliminary light emission is image-picked up by an imaging part 17. The picked-up image under the preliminary light emission is divided into a plurality of partial areas corresponding to a plurality of liquid crystal elements forming the light distribution changing part 15 arranged in a matrix, so as to acquire the luminance of each of the partial areas. Based on the acquired luminance, emitted light quantity in the regular light emission is set and also low transmittance is set to a light distribution control part 16 as the transmittance of part of the plurality of liquid crystal elements forming the light distribution changing part 15 corresponding to the partial area having the luminance exceeding saturation luminance, whereby part of the strobe light in the regular light emission is dimmed. The strobe light emitted from the strobe light source 14 by the regular light emission is radiated to an object to be illuminated after light distribution is adjusted by the light distribution changing part 15. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a light distribution adjustment method for adjusting the light distribution of illumination light in accordance with an object to be illuminated located in an illumination range, an illumination device that emits illumination light with adjusted light distribution, and an imaging device including the illumination device. .

  Conventionally, an illuminating device provided in an imaging device or the like uses a lens and a reflector to irradiate the illumination light with a uniform light intensity distribution on a plane substantially parallel to the illumination light exit surface. The light distribution is adjusted. However, generally, a plurality of objects to be illuminated having different distances from the illumination device are often located in the illumination range of the illumination device. In such a case, the illumination object located at a short distance from the illumination device is illuminated brightly by the illumination light, and the illumination object located at a long distance is illuminated darkly. Therefore, when the imaging device captures a plurality of objects to be illuminated that are located in the illumination range under illumination light, the objects to be illuminated at a short distance and a long distance are overexposed and underexposed, respectively. Only proper exposure is often obtained.

Therefore, in order to suppress a difference in brightness generated in a plurality of objects to be illuminated under illumination light, Patent Document 1 discloses that a liquid crystal plate is arranged in the peripheral portion of the front surface of the light source, and a transmittance of a part of the liquid crystal plate. An illuminating device that reduces a part of the illumination light that illuminates an object to be illuminated located at a short distance from the illuminating device is described. Patent Document 2 discloses an illumination in which the distance to an object to be illuminated is measured by a distance measuring unit, and the light emission amount is adjusted in accordance with the distance to the object to be illuminated in synchronization with the direction of slit exposure of the imaging device. An apparatus is described. Further, in Patent Document 3, a shielding plate having a rotation mechanism is arranged on the front side of the light source, and a part of the illumination light is shielded, thereby illuminating based on the distance to the illuminated object measured by the distance measuring means. An illumination device for adjusting the light distribution is described.
Japanese Patent Publication No. 61-19021 JP 9-325388 A JP 2003-140234 A

  However, the illumination device described in Patent Document 1 only reduces a part of the amount of illumination light that passes through the peripheral portion of the front surface of the light source, and illuminates an object to be illuminated located in the peripheral portion of the illumination range. There was a limitation that only the amount of light can be adjusted. The illumination device described in Patent Document 2 adjusts the amount of illumination light only for a one-dimensional distribution parallel to the advancing direction of slit exposure with respect to a plane substantially parallel to the exit surface of the illumination light. There is a problem that the distribution cannot be adjusted according to the position of each of the plurality of objects to be illuminated.

  In the illumination device described in Patent Document 2, the amount of light emission is adjusted in synchronization with the speed in the direction of slit exposure by the focal plane shutter, that is, the shutter speed. Therefore, the illumination device is illuminated in the imaging device including the illumination device. When the optimum light emission amount according to the object is set, there is also a problem that it is impossible to change to the optimum shutter speed, that is, the exposure time in order to prevent camera shake. The illumination device described in Patent Document 3 has a problem that it is difficult to finely adjust the light distribution of illumination light by accumulating a large number of light shielding plates provided with a rotation mechanism.

  The present invention has been made in view of such circumstances, and obtains luminances of a plurality of partial regions corresponding to a plurality of light distribution change elements forming a light distribution change unit from a captured image of an illumination range under illumination light. Then, by controlling the optical parameters of each of the plurality of light distribution changing elements based on the respective luminances, it is possible to prevent the objects to be illuminated located at a short distance and a long distance from the lighting device from being excessively bright and insufficient. An object of the present invention is to provide a light distribution adjusting method and an illumination device, and an imaging device including the illumination device that prevents an object to be imaged located at a short distance and a long distance from the illumination device from being overexposed and underexposed. To do.

  The light distribution adjustment method according to the present invention includes a light source and a plurality of light distribution change elements arranged two-dimensionally, a light distribution change unit that changes the light distribution of the illumination light emitted from the light source, and the illumination light In the light distribution adjustment method of illumination light emitted by an illumination device including an imaging unit that images an illumination range, the illumination range of the illumination light is imaged by the imaging unit, and a captured image is obtained. The present invention is characterized in that the luminance of a plurality of partial areas corresponding to each of the plurality of light distribution changing elements is acquired, and the optical parameter of each of the plurality of light distribution changing elements is controlled based on the luminance.

  The light distribution adjustment method according to the present invention includes a light source and a plurality of light distribution change elements arranged two-dimensionally, a light distribution change unit that changes the light distribution of the illumination light emitted from the light source, and the illumination light In a light distribution adjustment method of illumination light emitted by an illumination device including a distance measuring unit that measures a distance to an object to be illuminated located in the illumination range, the distance from the light source to the object to be illuminated is determined. It is measured by the distance measuring unit, and the optical parameter of each of the plurality of light distribution changing elements is changed based on the distance.

  The light distribution adjustment method according to the present invention includes a light source and a plurality of light distribution change elements arranged two-dimensionally, a light distribution change unit that changes the light distribution of the illumination light emitted from the light source, and the illumination light A distance measuring unit that measures a distance to an object to be illuminated located in the illumination range, a luminance acquisition unit that acquires the luminance of the illumination range of the illumination light, and an imaging unit that images the illumination range of the illumination light In the light distribution adjustment method of illumination light emitted by the illumination device, the distance from the light source to the object to be illuminated located in the illumination range is measured by the distance measuring unit, and the light emission amount of the light source based on the luminance and the distance, respectively. In addition, each of the optical parameters of each of the plurality of light distribution changing elements is changed.

  The light distribution adjusting method according to the present invention includes a light source composed of a plurality of light emitting elements arranged two-dimensionally and a plurality of light distribution changing elements corresponding to the plurality of light emitting elements, and the light emitted from the light source. In the light distribution adjustment method of illumination light irradiated by an illumination device including a light distribution change unit that changes the light distribution and an imaging unit that images the illumination range of the illumination light, the illumination range of the illumination light is The captured image is captured by the imaging unit, the brightness of the plurality of partial regions corresponding to the plurality of light emitting elements is acquired from the captured image, and the optical characteristics of the plurality of light distribution changing elements are obtained based on the brightness. It is characterized by changing parameters.

  The light distribution adjustment method according to the present invention is characterized in that the light emission amount of the light source is changed based on the luminance.

  The light distribution adjustment method according to the present invention is characterized in that the light emission amount of each of the plurality of light emitting elements is changed based on the luminance.

  An illumination device according to the present invention includes a light source and a light distribution changing unit that is disposed on a front side of the light source and changes a light distribution of illumination light incident on a rear surface from the light source, and the light distribution of the illumination light In the illumination device that adjusts and irradiates, the light distribution change unit includes a plurality of light distribution change elements arranged two-dimensionally, an image pickup unit that picks up an illumination range of the illumination light, and the image pickup unit A luminance acquisition unit that acquires the luminance of a plurality of partial regions corresponding to each of the plurality of light distribution change elements from the captured image, and each of the plurality of light distribution change elements based on the respective luminances acquired by the luminance acquisition unit And a light distribution control unit that controls the optical parameters.

  The illumination device according to the present invention further includes a high luminance region detection unit that has a threshold value and detects a high luminance region having a luminance exceeding the threshold value from the captured image, and the light distribution control unit includes the plurality of light distribution control units. Among these light distribution changing elements, the optical parameter of each of the light distribution changing elements corresponding to the high luminance region is controlled.

  In the illumination device according to the present invention, the light distribution changing element is composed of a liquid crystal element having variable transmittance, and the light distribution control unit is configured to control the transmittance of each of the plurality of liquid crystal elements. Features.

  In the illumination device according to the present invention, the light distribution changing element is formed of a liquid crystal lens having a variable irradiation angle, and the light distribution control unit is configured to control an irradiation angle of each of the plurality of liquid crystal lenses. Features.

In the illumination device according to the present invention, the light distribution changing element is a liquid lens having a variable focal length,
The light distribution control unit is configured to control a focal length of each of the plurality of liquid lenses.

  An imaging device according to the present invention includes the above-described illumination device.

  In the first invention and the seventh invention, pre (preliminary) light emission is performed before the main light emission of the illumination light, and the illumination range of the illumination light by the pre-light emission is imaged by the imaging unit. The captured image of the illumination range is divided into a plurality of partial areas corresponding to the plurality of light distribution changing elements arranged in two dimensions that form the light distribution changing unit, and the respective luminances are acquired. After the optical parameter of each of the plurality of light distribution changing elements forming the light distribution changing unit is controlled so as to reduce part of the illumination light corresponding to the partial area having high luminance, the main emission of the illumination light is performed.

  In the second invention, before the main emission of the illumination light is performed, each distance from the illumination device to the plurality of objects to be illuminated located in the illumination range is measured. After the optical parameters of each of the plurality of light distribution changing elements forming the light distribution changing unit are dimmed to reduce a part of the illumination light that illuminates the object to be illuminated at a short distance from the illumination device, the main emission of the illumination light is performed. Done.

  In the third invention, the captured image of the illumination range under pre-emission imaged by the imaging unit is divided into a plurality of partial areas to acquire the respective luminances, and the luminance acquisition unit determines the luminance of the illumination range. To be acquired. The optical parameters of each of the plurality of light distribution changing elements are controlled so as to reduce part of the illumination light corresponding to the partial area having high luminance, and an insufficiently bright area may be generated in the illumination range under the main light emission. After the light emission amount of the light source is controlled based on the luminance acquired by the luminance acquisition unit, the main emission of the illumination light is performed.

  In the fourth aspect of the invention, pre-emission is performed before the main emission of the illumination light is performed, and the illumination range of the illumination light by the pre-emission is imaged by the imaging unit. The captured image of the illumination range is divided into partial areas corresponding to the plurality of light-emitting elements that are two-dimensionally arranged as a light source, and respective luminances are acquired. After the optical parameter of each of the plurality of light distribution changing elements forming the light distribution changing unit is controlled so as to reduce part of the illumination light corresponding to the partial area having high luminance, the main emission of the illumination light is performed.

  In the fifth invention, the captured image of the illumination range under pre-emission imaged by the imaging unit is divided into a plurality of partial areas, and the respective luminances are acquired. The optical parameters of each of the plurality of light distribution change elements are controlled so as to reduce part of the illumination light corresponding to the partial area having high luminance, and an insufficiently bright area does not occur in the illumination range in the main emission. After the light emission amount of the light source is controlled based on the acquired brightness, the main light emission of the illumination light is performed.

  In the sixth invention, the captured image of the illumination range under pre-emission imaged by the imaging unit is divided into a plurality of partial areas, and the respective luminances are acquired. The optical parameters of each of the plurality of light distribution changing elements are controlled so as to diminish a part of the illumination light corresponding to the partial area having high brightness, and a part of the illumination light corresponding to the partial area having low brightness is controlled. After the amount of light emitted from each of the plurality of light emitting elements forming the light source is controlled to increase, the main light emission of the illumination light is performed.

  In the eighth invention, a saturated region (high luminance region), which is a partial region having a luminance exceeding a preset threshold by being divided from a captured image acquired by imaging an illumination range under pre-light emission, is detected. The The light distribution control unit controls the optical parameters of the light distribution change element corresponding to the saturation region among the plurality of light distribution change elements forming the light distribution change unit so as to reduce part of the illumination light corresponding to the saturation region. Is done.

  In the ninth aspect of the invention, pre-emission is performed before the main emission of illumination light is performed, and the illumination range under pre-emission is imaged by the imaging unit. The captured image of the illumination range is divided into a plurality of partial areas corresponding to the plurality of liquid crystal elements forming the light distribution changing unit, and the respective luminances are acquired. The light distribution control unit reduces the transmittance of the corresponding liquid crystal element among the plurality of liquid crystal elements forming the light distribution changing unit so as to reduce a part of the illumination light corresponding to the partial region having high luminance. After being controlled, the main emission of the illumination light is performed.

  In the tenth invention, pre-emission is performed before the light source performs the main emission, and the illumination range under the pre-emission is imaged by the imaging unit. The captured image of the illumination range is divided into a plurality of partial areas corresponding to the plurality of liquid crystal lenses forming the light distribution changing unit, and the respective luminances are acquired. A saturated region and a low luminance region are extracted from the plurality of partial regions. The irradiation angle of the liquid crystal lens corresponding to the saturation region among the plurality of liquid crystal lenses forming the light distribution change unit is controlled by the light distribution control unit so that a part of the illumination light illuminating the saturation region is directed to the low luminance region. Thereafter, the main emission of the illumination light is performed.

  In the eleventh aspect of the invention, pre-emission is performed before the light source performs the main emission, and the illumination range under the pre-emission is imaged by the imaging unit. The captured image of the illumination range is divided into a plurality of partial areas corresponding to the plurality of liquid lenses constituting the light distribution changing unit, and the respective luminances are acquired. The liquid corresponding to the saturation region among the plurality of liquid lenses forming the light distribution changing unit so as to diffuse and reduce part of the illumination light irradiated to the object located in the saturation region by the light distribution control unit After the focal length of the lens is controlled, the main emission of the illumination light is performed.

  In the twelfth aspect of the invention, illumination light whose light distribution is adjusted according to the object to be imaged that is located in the imaging range by the illumination device described above is irradiated, and the object to be imaged under the illumination light is imaged.

  In the present invention, the brightness of a plurality of partial areas corresponding to each of a plurality of light distribution change elements forming a light distribution change unit is acquired from a captured image of an illumination range under illumination light, and based on each brightness By controlling the optical parameters of each of the plurality of light distribution changing elements, it becomes possible to irradiate the illumination light that is not excessively bright and insufficient in brightness to be illuminated at a short distance and a long distance from the illumination device. In the present invention, it is possible to obtain a captured image that does not cause overexposure and underexposure by capturing an image of an object to be captured under illumination light with adjusted light distribution.

Embodiment 1
Hereinafter, the present invention will be described in detail with reference to the drawings showing embodiments thereof. FIG. 1 is a block diagram showing an internal hardware configuration of the strobe lighting device according to the first embodiment. The white arrow in the figure indicates the direction of light emitted from the strobe light source 14 and directed to the rear surface of the light distribution changing unit 15. In the figure, reference numeral 1 denotes a strobe lighting device. The strobe lighting device 1 has a strobe light source 14 that emits strobe light emitted from a xenon lamp, which will be described later, and an arrangement that changes the light distribution of the strobe light emitted from the strobe light source 14. The light changer 15 and the light distribution controller 16 that controls each of the plurality of liquid crystal elements (light distribution changer) constituting the light distribution changer 15 to have a set transmittance (optical parameter).

  In this embodiment, an example in which the present invention is applied to a strobe lighting device having a strobe light source will be described by replacing the lighting device and the light source with the strobe lighting device 1 and the strobe light source 14, respectively. However, the present invention is not limited to this. A light source that emits steady light such as a lamp may be provided, and the light source may be applied to an illumination device that emits steady light as illumination light.

  The strobe lighting device 1 has a driving power supply 13 including a lighting circuit and a power supply circuit (not shown) for driving the strobe light source 14, and a light emission amount of strobe light emitted from the strobe light source 14 via the driving power supply 13 to a set light emission amount. A light emission amount control unit 12 to be controlled, an image capturing unit 17 that captures an illumination range of strobe light that is transmitted through the light distribution changing unit 15 and emitted toward the object to be illuminated, and an operation receiving unit 18 that receives an operation by a user , A CPU (Central Processing Unit) 11 as a control unit, a RAM (Random Access Memory) 19, and a ROM 20 for storing each determination table described later including a strobe control program 201. The imaging unit 17 is configured by a CCD (Charge Coupled Device) image sensor or the like.

  The light emission amount control unit 12 is configured based on a light emission time control method in which the light emission amount is controlled based on the light emission time, determines the light emission time based on the set light emission amount, and instructs the drive power supply 13. The drive power supply 13 supplies power to the strobe light source 14 according to the instructed emission time and a preset strobe voltage. The light distribution control unit 16 is configured to control the transmittance of each liquid crystal element by determining and applying a voltage to be applied to each of the plurality of liquid crystal elements forming the light distribution changing unit 15 from the set transmittance. ing. The ROM 20 stores a light emission amount determination table 202 and a light distribution determination table 203, which will be described later, together with a strobe control program 201.

  The CPU 11 is connected to each hardware part of the strobe lighting device 1 via the bus 21, controls each hardware part, and reads the strobe control program 201 stored in the ROM 20 into the RAM 19 and executes it. Various software processes are executed. The strobe light source 14 and the light distribution changing unit 15 constitute a strobe light emitting unit 22. In addition, the CPU 11 functions as a luminance acquisition unit by performing multi-photometry processing that divides a captured image under non-light emission and pre-light emission, which will be described later, into a plurality of partial areas in accordance with the strobe control program 201 and acquires respective luminances. In addition, it is also configured to function as a saturation region detection unit (high luminance region detection unit) that extracts a saturation region (high luminance region) described later based on the acquired luminance or the like.

  2 and 3 are a schematic perspective view showing the strobe light emitting portion 22 and a schematic structural sectional view taken along line III-III in FIG. The strobe light source 14 has a rectangular tube-shaped xenon lamp 142 that emits strobe light inside a rectangular housing 141 having a rectangular opening, and strobe light emitted by the xenon lamp 142 is directed toward the opening surface of the case 141. And a bowl-shaped reflecting portion 143 that reflects the light. The bottom of the bowl-shaped reflecting portion 143 is fixed to the bottom surface of the casing 141 so as to extend along the long side of the rectangular opening of the casing 141. Both ends of the xenon lamp 142 are fixed to the inner side surface of the casing 141 so that the axial direction is parallel to the long side of the rectangular opening of the casing 141.

  The light distribution changing unit 15 includes a flat part 141a provided at the periphery of the rectangular opening of the housing 141 and a holding part 151 having a substantially L-shaped cross section so that the buffer member 152, 152 whose outer peripheral part is frame-shaped. The rectangular opening of the housing 141 is covered by being sandwiched therebetween. The holding part 151 is fixed to the flat part 141a with screws or the like. The strobe light emitted from the xenon lamp 142 is incident on each of a plurality of liquid crystal elements that are two-dimensionally arranged in a matrix that forms the light distribution changing unit 15, and is attenuated according to the transmittance set in each liquid crystal element. Is adjusted.

  The example of the light distribution changing unit 15 shown in FIG. 2 includes 96 liquid crystal elements arranged in a matrix of 12 horizontal and 8 vertical. When the operation accepting unit 18 accepts an operation for instructing the emission of strobe light by the user, the strobe lighting device 1 emits strobe light according to the operation, that is, before performing main light emission, under no light emission and pre-light emission. The captured image obtained by imaging the illumination range of the strobe light below is divided into multiple partial areas, and multi-photometry is performed to acquire the respective brightness, followed by the main flash amount setting and strobe light distribution After making the change, perform the main flash. Here, multi-photometry will be described.

  The strobe lighting device 1 images the illumination range under no light emission by the imaging unit 17. The captured image under no light emission is divided into a plurality of partial regions corresponding to the plurality of liquid crystal elements constituting the light distribution changing unit 15, and the luminance Bn of each partial region is obtained. The luminance of the partial area may be the luminance of the partial area obtained by calculating an average value of a plurality of luminance data included in the image data in the partial area. The luminance Bn of each partial region under no light emission corresponds to the luminance of the object illuminated by natural light. The maximum transmittance is set in the light distribution control unit 16 as the transmittance of all the liquid crystal elements constituting the light distribution changing unit 15, and the maximum light emission (full light emission) of the strobe light source 14 to suppress power consumption during pre-emission. The pre-emission amount Ip that is equal to or less than the emission amount at the time and set in advance is set in the emission amount control unit 12.

  The strobe lighting device 1 has a uniform light distribution and irradiates strobe light with a small amount of light to the illumination range by pre-emission, and images the illumination range under pre-emission by the imaging unit 17. The captured image under the pre-light emission is divided into a plurality of partial areas corresponding to the plurality of liquid crystal elements forming the light distribution changing unit 15 in the same manner as the captured image under the non-light emission, and the luminance Bp of each partial area is acquired. The The luminance Bp of each partial region under pre-emission corresponds to the luminance of the object illuminated by natural light and strobe light during pre-emission.

  FIG. 4 is a schematic diagram illustrating an example of a captured image and a divided captured image under pre-emission according to the first embodiment. FIG. 4 shows the pre-emission captured image captured by the imaging unit 17 and the captured image divided into a plurality of partial areas, arranged in the order of (a) and (b). A captured image 171 under pre-light emission shown in FIG. 4A includes a region 171a in which a person located at a short distance from the front side, that is, the strobe lighting device 1, and a far side, that is, a long distance from the strobe lighting device 1. A region 171b in which the background located at is darkly illuminated by strobe light is imaged. In the example shown in FIG. 4B, the captured image 171 is divided into 96 partial areas that correspond one-to-one with each of the 96 liquid crystal elements arranged in a matrix that forms the light distribution changing unit 15. Next, the actual light emission amount setting will be described.

The strobe lighting device 1 extracts the lowest brightness BLp having the lowest brightness from the brightness Bp of each partial area under pre-emission, and extracts the partial area having the lowest brightness BLp as the lowest brightness area. The strobe lighting device 1 extracts the brightness BLn of the partial area corresponding to the lowest brightness area from the brightness Bn of each partial area under no light emission. The strobe lighting device 1 reads the lower limit luminance Bt under pre-emission stored in advance in the ROM 20 and calculates the ratio Ra using the following equation.
Ra = (Bt−BLp) / (BLp−BLn) (1)

  FIG. 5 is a table showing a data example of the light emission amount determination table. The light emission amount determination table 202 stores a plurality of light emission amounts associated with a plurality of values of the ratio Ra, and the light emission amount is shown as a ratio with the luminance at full light emission being 100%. In the example shown in FIG. 5, the light emission amount 50% to the light emission amount 100% are stored in association with the values Ra to 1 of the ratio Ra. As the value of the ratio Ra is increased, the minimum luminance BLp is significantly lower than the lower limit luminance Bt. Therefore, the ratio Ra and the light emission amount are stored in the main light emission amount determination table 202 so that the light emission amount is increased. The ratio Ra and the light emission amount may be obtained empirically in advance and stored in the light emission amount determination table 202. The strobe lighting device 1 reads the light emission amount corresponding to the ratio Ra from the light emission amount determination table 202 and sets it in the light emission amount control unit 12 as the main light emission amount If.

  When the value of the ratio Ra is stored in the light emission amount determination table 202 and is between two consecutive values, the value of the ratio Ra before and after and the light emission amount associated with each value are based on a predetermined function. The amount of light emission may be obtained by complementation. For the ratio Ra less than the minimum value and greater than or equal to the maximum value Ra stored in the light emission amount determination table 202, it is preferable to set the light emission amount 50% and 100%, respectively. In accordance with the light emission amount determination table 202, the main light emission amount If is set so that the luminance of the lowest luminance region corresponding to the object located at the farthest distance is not less than the lower limit luminance Bt. Next, the change in the light distribution of the strobe light will be described.

The strobe lighting device 1 calculates the luminance Bf of each partial region predicted when the strobe light having the main light emission amount If is irradiated with all the liquid crystal elements forming the light distribution changing unit 15 being set to have the maximum transmittance. Calculated by
Bf = k1 · (Bp−Bn) · (If / Ip) + Bn (2)
Here, k1 represents a proportionality constant, and is preferably obtained in advance and stored in the ROM 20 in advance. The strobe lighting device 1 reads out the saturated luminance (threshold value) Bs stored in advance in the ROM 20 among the partial regions, and calculates the partial region where the luminance Bf exceeding the luminance Bs is calculated, that is, the saturated region (high luminance region). Extract. The strobe lighting device 1 extracts the luminance Bn of the partial region corresponding to the saturated region from the luminance Bn of each partial region under no light emission, and extracts the saturated luminance Bs, the luminance Bf exceeding the saturated luminance Bs, and the extracted luminance Bn. Based on the above, the ratio Rb is calculated using the following equation.
Rb = (Bs−Bn) / (Bf−Bn) (3)

  FIG. 6 is a table showing a data example of the light distribution determination table 203 according to the first embodiment. The light distribution determination table 203 stores a plurality of transmittances associated with a plurality of values of the ratio Rb. In the example shown in FIG. 6, the transmittances from 100% to 20% are stored in association with the values of the ratio Rb from 1 to 0.2. When the luminance Bf of the saturation region is much higher than the saturation luminance Bs, the value of the ratio Rb is small. Therefore, the ratio Rb and the transmittance are displayed in the light distribution determination table 203 so that the transmittance is reduced to reduce the strobe light. It is remembered. The ratio Rb and the transmittance may be obtained empirically in advance and stored in the light distribution determination table 203. The strobe lighting device 1 reads from the light distribution determination table 203 the transmittance corresponding to the ratio Rb calculated for each partial region. The strobe lighting device 1 includes the light distribution control unit 16 so that the transmittance of the liquid crystal elements corresponding to the saturation region among the plurality of liquid crystal elements constituting the light distribution changing unit 15 becomes the transmittance read from the light distribution determination table 203. Set to.

  When the value of the ratio Rb is stored in the light distribution determination table 203 and is between two consecutive values, the value of the ratio Rb before and after and the transmittance associated with each value are based on a predetermined function. It is better to obtain the transmittance by complementing. By changing the transmittance of the liquid crystal element corresponding to the saturation region, the transmittance of the corresponding liquid crystal element is reduced so that the luminance of the object to be illuminated located at a short distance does not exceed the saturation luminance Bs. While part of the light is dimmed, the transmittance of other liquid crystal elements is maintained at 100% so that sufficient luminance can be obtained for other objects to be illuminated. The strobe lighting device 1 causes the light emission amount control unit 12 to supply power to the strobe light source 14 via the drive power supply 13 to cause the strobe light source 14 to emit light. The strobe light emitted from the strobe light source 14 by the main light emission is transmitted through each liquid crystal element forming the light distribution changing unit 15 whose transmittance is controlled, the light distribution is changed, and the object to be illuminated in the illumination range is irradiated.

  FIG. 7 is a flowchart showing a procedure of light emission processing executed by the strobe lighting device 1 according to the first embodiment. The CPU 11 determines whether or not the operation reception unit 18 has received a light emission operation instructing to emit strobe light (step S11). When it is determined that the light emission operation has not been received (NO in step S11), the CPU 11 returns the process to step S11 for determining whether or not the light emission operation has been received. If the CPU 11 determines that the light emission operation has been received (YES in step S11), the illumination range under no light emission and pre-light emission is imaged, and each of the captured images is divided into a plurality of partial areas. A multi-photometry process (described later) for obtaining each Bp is executed (step S12).

  The CPU 11 executes a later-described main light emission amount setting process for determining the main light emission amount based on the luminance Bn, the luminance Bp, and the like of each partial area acquired by the multi-photometry processing and setting the light emission amount control unit 12 (step S13). . The CPU 11 determines the transmittance of each of the plurality of liquid crystal elements constituting the light distribution changing unit 15 based on the luminance Bn and the luminance Bp of each partial area acquired by the multi-photometry processing, and sets the transmittance in the light distribution control unit 16. A light distribution change process described later for changing the light distribution of the strobe light is executed (step S14). The CPU 11 causes the light emission amount control unit 12 to perform main light emission through the drive power supply 13 (step S15).

  The CPU 11 determines whether or not the power is turned off by detecting a power off signal that is output when a power switch (not shown) provided in the strobe lighting device 1 is disconnected (step S16). When determining that the power is not turned off (NO in step S16), the CPU 11 returns the process to step S11 for determining whether or not the light emission operation is accepted. If the CPU 11 determines that the power has been turned off (YES in step S16), the light emission process ends.

  FIG. 8 is a flowchart showing the procedure of the multi-photometry process. CPU11 images the illumination range under no light emission by image pick-up part 17 (Step S21). The CPU 11 divides the captured image of the illumination range under no light emission into a plurality of partial areas corresponding to the plurality of liquid crystal elements two-dimensionally arranged in a matrix of the light distribution changing unit 15 (step S22). The CPU 11 acquires the luminance Bn under no light emission of each of the plurality of partial areas (step S23). The CPU 11 reads the pre-emission amount Ip stored in advance in the ROM 20 and sets it in the emission amount control unit 12 (step S24). The CPU 11 sets substantially the same maximum transmittance as the transmittance of all the liquid crystal elements constituting the light distribution changing unit 15 in the light distribution control unit 16 (step S25).

  The CPU 11 causes the light emission amount control unit 12 to pre-emit the strobe light source 14 via the drive power supply 13, and images the illumination range under pre-emission using the imaging unit 17 (step S26). The CPU 11 divides the captured image of the illumination range under the pre-light emission into a plurality of partial areas corresponding to the plurality of liquid crystal elements two-dimensionally arranged in a matrix of the light distribution changing unit 15 (step S27). The CPU 11 acquires the luminance Bp under the pre-light emission of each of the plurality of partial areas (step S28), and ends the multi-photometry process.

  FIG. 9 is a flowchart showing a procedure of the main light emission amount setting process according to the first embodiment. The CPU 11 extracts the minimum luminance region having the minimum luminance BLp and the minimum luminance BLp, which are minimum, from among the plurality of pre-light-emitting luminance Bp and the plurality of partial regions acquired by the multi-photometry processing described above (step S31). . The CPU 11 extracts the brightness BLn of the non-light-emitting partial area corresponding to the minimum brightness area from the plurality of non-light-emitting brightness Bn acquired by the multi-photometry process (step S32). The CPU 11 reads the lower limit luminance Bt stored in advance in the ROM 20 (step S33). CPU11 calculates ratio Ra using Formula (1) (step S34). The CPU 11 reads the light emission amount associated with the ratio Ra in the light emission amount determination table 202 stored in the ROM 20 (step S35). The CPU 11 sets the read light emission amount as the main light emission amount If in the light emission amount control unit 12 (step S36), and ends the main light emission amount setting process.

  FIG. 10 is a flowchart showing the procedure of the light distribution change process according to the first embodiment. CPU11 calculates the brightness | luminance Bf of each partial area estimated under this light emission using Formula (2) (step S41). The CPU 11 reads the saturated luminance Bs stored in the ROM 20 (step S42). The CPU 11 extracts a partial area where the luminance Bf exceeding the saturated luminance Bs is calculated, that is, a saturated area, from among the plurality of partial areas where the luminance Bf is calculated (step S43). The CPU 11 extracts the brightness Bn acquired from the non-light-emitting partial area corresponding to the saturation area among the plurality of non-light-emitting brightness Bn acquired by the multi-photometry process (step S44).

  The CPU 11 calculates the ratio Rb of each partial region using Expression (3) (Step S45). CPU11 reads the transmittance | permeability matched with ratio Rb in the light distribution determination table 203 memorize | stored in ROM20 (step S46). The CPU 11 sets the light transmission control unit 16 so that the read transmittance becomes the transmittance of the liquid crystal element corresponding to the saturation region among the plurality of liquid crystal elements forming the light distribution changing unit 15 (step S47). The light change process is terminated.

  In the first embodiment, the case where the light distribution changing unit 15 includes 96 liquid crystal elements arranged in a matrix of 12 horizontal and 8 vertical is shown. However, the present invention is not limited to this, and the number is less than 96. The light distribution changing unit 15 may be composed of 97 or more liquid crystal elements. In the multi-photometry processing, the case where the captured image is divided into partial areas corresponding to the plurality of liquid crystal elements forming the light distribution changing unit 15 on a one-to-one basis is shown. It may be divided into partial regions composed of a plurality of liquid crystal elements. In this case, the plurality of liquid crystal elements forming the light distribution changing unit 15 are two-dimensionally arranged in a matrix, and divided into a plurality of light distribution changing areas each formed of a plurality of liquid crystal elements, and a captured image is obtained in multi-photometry processing. It is good to divide | segment into the some partial area corresponding to each of several light distribution change area | regions one to one. Further, the light distribution control unit 16 is configured to set the transmittance for each of the plurality of light distribution change regions, and to set substantially the same transmittance as the transmittance of the plurality of liquid crystal elements forming the light distribution change region. Good.

  In the first embodiment, the light emission amount control unit 12 is configured based on the light emission time control method. However, the present invention is not limited to this, and a voltage control method for controlling the light emission amount with a strobe voltage is used. You may comprise based. In this case, the drive power supply 13 is instructed by the light emission amount control unit 12 with the strobe voltage determined and instructed based on the set light emission amount, and applied to the strobe light source 14 according to the instructed strobe voltage and a preset light emission time. It may be configured to supply power. In addition, since the strobe voltage or the light emission time is related to the power consumption at the time of strobe light emission, a plurality of types are set in the drive power supply 13 and selected based on the remaining capacity of a battery (not shown) connected to the drive power supply 13. You may comprise.

Embodiment 2
FIG. 11 is a block diagram showing an internal hardware configuration of the strobe lighting device according to the second embodiment. In the present embodiment, light distribution adjustment is performed based on the distance from the strobe lighting device to the object to be illuminated, whereas light distribution adjustment is performed based on the luminance of each partial area acquired by multi-photometry in the first embodiment. Is configured to do. In the figure, reference numeral 3 denotes a strobe lighting device, which includes a light receiving sensor 31 that acquires the luminance of the illumination range and a distance measuring sensor 32 that acquires the distance to the object to be illuminated located in the illumination range. The distance measuring sensor 32 includes a distance image sensor that simultaneously detects distances and images to a plurality of objects to be illuminated located in the illumination range and acquires a distance distribution image. The strobe lighting device 3 performs photometry to obtain the brightness of the strobe light illumination range, set the strobe light emission amount, measure the distance, and change the strobe light distribution before executing the main flash. It is configured to adjust the light distribution of the strobe light.

The strobe lighting device 3 acquires the luminance Bn and luminance Bp under non-light emission and pre-light emission, respectively, measured by the light receiving sensor 31 by a photometric process described later. The strobe lighting device 3 reads the lower limit luminance Bt under pre-emission stored in advance in the ROM 20, calculates the ratio Ra using the following equation, and reads out the emission amount corresponding to the ratio Ra from the emission amount determination table 202. The actual light emission amount If is set in the light emission amount control unit 12.
Ra = (Bt−Bp) / (Bp−Bn) (4)

The strobe lighting device 3 divides the distance distribution image acquired by the distance measuring sensor 32 into a plurality of matrix-like partial areas corresponding to the plurality of liquid crystal elements constituting the light distribution changing unit 15 and is located in each partial area. A distance D to the object to be illuminated is acquired. When there are a plurality of distance data in one partial area, the average value of the plurality of distance data may be the distance D of the partial area. Moreover, it is good also considering the minimum distance or the maximum distance as the distance D which the said partial area has among several distance D which exists in one partial area. The minimum distance Dmin and the maximum distance Dmax are extracted from the acquired distances D of the plurality of partial areas, and the ratio Rc in each partial area is calculated based on the following equation.
Rc = (D−Dmin) / (Dmax−Dmin) (5)

  FIG. 12 is a table showing a data example of the light distribution determination table 203 according to the second embodiment. The light distribution determination table 203 stores a plurality of transmittances associated with a plurality of values of the ratio Rc. In the example shown in FIG. 12, the transmittance from 100% to 10% is stored in association with each value of the ratio Rc from 1 to 0.3. As the value of the ratio Rc decreases, the light distribution determination table 203 stores the ratio Rc and the transmittance so that the transmittance decreases to reduce the strobe light because the position is closer to the strobe lighting device 3. . The ratio Rc and the transmittance may be obtained in advance by experience and stored in the light distribution determination table 203. The strobe lighting device 3 reads out the transmittance corresponding to the ratio Rc calculated for each partial region from the light distribution determination table 203. The strobe lighting device 3 sets the light distribution control unit 16 so that the transmittance of the liquid crystal element corresponding to each partial region becomes the transmittance read from the light distribution determination table 203.

  When the value of the ratio Rc is stored in the light distribution determination table 203 and is between two consecutive values, the ratio Rc is determined based on a predetermined function from the previous and subsequent ratio Rc values and the transmittance associated with each. It is better to obtain the transmittance by complementing. For the ratio Rc stored in the light distribution determination table 203 that is less than the minimum value and greater than or equal to the maximum value, the transmittances 100% and 10% may be set, respectively. Accordingly, a part of the strobe light is dimmed by controlling the transmittance of the corresponding liquid crystal element to be reduced so that the luminance of the object to be illuminated located at a short distance does not become excessive. The strobe lighting device 3 causes the light emission amount control unit 12 to supply power to the strobe light source 14 via the drive power supply 13 to cause the strobe light source 14 to perform main light emission. The strobe light emitted from the strobe light source 14 by the main light emission is transmitted through each liquid crystal element forming the light distribution changing unit 15 in which the transmittance is controlled, the light distribution is changed, and the illuminated object is irradiated in the illumination range.

  FIG. 13 is a flowchart illustrating a procedure of light emission processing executed by the strobe lighting device 3 according to the second embodiment. The CPU 11 determines whether or not the operation reception unit 18 has received a light emission operation instructing to emit strobe light (step S51). When determining that the light emission operation has not been received (NO in step S51), the CPU 11 returns the process to step S51 for determining whether the light emission operation has been received. If the CPU 11 determines that the light emission operation has been accepted (YES in step S51), the CPU 11 executes a photometry process described later for acquiring the respective luminance Bn and luminance Bp in the illumination range under no light emission and under pre-light emission (step S52). . The CPU 11 determines a main light emission amount based on the luminance Bn, Bp, etc. acquired by the photometry process, and executes a later-described main light emission amount setting process set in the light emission amount control unit 12 (step S53). CPU11 performs the below-mentioned ranging process which acquires the distance to the to-be-illuminated object located in an illumination range (step S54).

  The CPU 11 determines the transmittance based on the distance acquired by the distance measurement process, sets it in the light distribution control unit 16, and executes a light distribution change process described later to change the light distribution of the strobe light (step S55). The CPU 11 causes the light emission amount control unit 12 to perform main light emission through the drive power supply 13 (step S56). The CPU 11 determines whether or not the power is turned off by detecting a power-off signal that is output when a power switch (not shown) provided in the strobe lighting device is disconnected (step S57). When determining that the power is not turned off (NO in step S57), the CPU 11 returns the process to step S51 for determining whether or not the light emission operation is accepted. If the CPU 11 determines that the power has been turned off (YES in step S57), the light emission process ends.

  FIG. 14 is a flowchart showing the procedure of photometry processing. CPU11 acquires the brightness | luminance Bn in the illumination range under no light emission from the light receiving sensor 31 (step S61). The CPU 11 reads the pre-light emission amount Ip stored in advance in the ROM 20 and sets it in the light emission amount control unit 12 (step S62). The CPU 11 sets the substantially same maximum transmittance as the transmittance of all the liquid crystal elements constituting the light distribution changing unit 15 in the light distribution control unit 16 (step S63). The CPU 11 causes the light emission amount control unit 12 to pre-emit the strobe light source 14 via the drive power supply 13 and obtains the luminance Bp in the illumination range under pre-emission from the light receiving sensor 31 (step S64), and ends the photometric process. To do.

  FIG. 15 is a flowchart showing a procedure of the main light emission amount setting process according to the second embodiment. The CPU 11 reads the lower limit luminance Bt stored in advance in the ROM 20 (step S71). CPU11 calculates ratio Ra using the brightness | luminance Bn and brightness | luminance Bp which were acquired by the above-mentioned multi-photometry process, and Formula (4) (step S72). The CPU 11 reads the light emission amount associated with the ratio Ra in the light emission amount determination table 202 stored in the ROM 20 (step S73). The CPU 11 sets the read light emission amount as the main light emission amount If in the light emission amount control unit 12 (step S74), and ends the main light emission amount setting process.

  FIG. 16 is a flowchart showing the procedure of distance measurement processing. The CPU 11 acquires a distance distribution image from the distance measuring sensor 32 (step S81). The CPU 11 divides the distance distribution image into a plurality of partial areas corresponding to the plurality of liquid crystal elements two-dimensionally arranged in a matrix of the light distribution changing unit 15 (step S82). CPU11 acquires distance D of each of a plurality of partial fields (Step S83), and ends distance measurement processing.

  FIG. 17 is a flowchart illustrating a procedure of light distribution change processing according to the second embodiment. The CPU 11 extracts the minimum minimum distance Dmin and the maximum maximum distance Dmax from among the plurality of distances D of the partial areas acquired by the distance measurement process (step S91). CPU11 calculates ratio Rc of each partial area using Formula (5) (Step S92). CPU11 reads the transmittance | permeability matched with ratio Rc in the light distribution determination table 203 memorize | stored in ROM20 (step S93). The CPU 11 sets in the light distribution control unit 16 so that the read transmittance becomes the transmittance of the liquid crystal element corresponding to each partial region among the plurality of liquid crystal elements constituting the light distribution changing unit 15 (step S94). The light distribution change process is terminated.

  The second embodiment is configured as described above, and other configurations and operations are the same as those of the first embodiment. Therefore, corresponding parts are denoted by the same reference numerals, and detailed description thereof is omitted.

Embodiment 3
In the present embodiment, the light distribution changing unit 15 is configured from a plurality of liquid crystal elements and the light distribution adjustment is performed by controlling the transmittance of each of the plurality of liquid crystal elements. The light distribution changing unit 15 is configured from the lens, and the light distribution adjustment is performed by controlling the irradiation angle of each of the plurality of liquid crystal lenses. The light distribution control unit 16 is configured to change the voltage applied to each of the plurality of liquid crystal lenses forming the light distribution change unit 15 based on the set irradiation angle, and to control the irradiation angle of the light beam passing through each liquid crystal lens. Has been. The strobe lighting device 1 is configured to adjust the light distribution of the strobe light by performing multi-photometry processing, changing the light distribution of the strobe light, and setting the main light emission amount of the strobe light before executing the main light emission.

  In the multi-photometry process according to the first embodiment, substantially the same maximum transmittance is set in the light distribution control unit 16 for all of the plurality of liquid crystal elements forming the light distribution changing unit 15, but the multi-photometry process according to the present embodiment is performed. In the photometric process, the light distribution control unit 16 sets substantially the same irradiation angle that is perpendicular to the light distribution change unit 15 to all of the plurality of liquid crystal lenses constituting the light distribution change unit 15. The strobe lighting device 1 acquires the respective luminance Bn and luminance Bp under no light emission and under pre-light emission by multi-photometry processing. Next, the light distribution adjustment of strobe light by controlling the irradiation angle of each liquid crystal lens will be described.

  FIG. 18 is a schematic diagram illustrating divided captured images and strobe light fluxes according to the third embodiment. FIG. 18 shows the captured image under pre-emission divided into a plurality of partial areas and the strobe light flux whose irradiation angle has been changed by the liquid crystal lens, arranged in the order of (a) and (b). A white arrow in FIG. 18B indicates a vertical direction with respect to the front surface of the light distribution changing unit 15. L1c and L2c in FIG. 18B indicate the irradiation directions before and after changing the irradiation angle of the strobe light that passes through one liquid crystal lens 15c among the plurality of liquid crystal lenses forming the light distribution changing unit 15. The light beam L1 and the light beam L2 are emitted according to the directions L1c and L2c, respectively. The irradiation angle θ indicates an angle formed by the irradiation directions L1c and L2c. The horizontal width of the light distribution changing unit 15 is shown to correspond to the horizontal width of the captured image 172, and the human image captured in the captured image 172 corresponds to the illuminated object 102. A light beam L1 that passes through the liquid crystal lens 15c before the irradiation angle and a light beam (not shown) that passes through the liquid crystal lens 15d illuminate a saturation region 172a and an unsaturated region 172b, which will be described later, respectively.

  In the example of the captured image under pre-emission shown in FIG. 18A, the image is divided into 40 partial areas corresponding to the 40 liquid crystal lenses forming the light distribution changing unit 15. The saturated region (high luminance region) 172a is a region where a person located at a short distance from the strobe lighting device 1 is brightly illuminated, and indicates a partial region having a luminance Bp exceeding the saturated luminance (threshold value) Bs. The unsaturated region (low luminance region) 172b is a region in which an object located at a long distance from the strobe lighting device 1 is illuminated darkly, and indicates a partial region having a luminance Bp equal to or lower than the saturated luminance Bs. The strobe lighting device 1 extracts a saturated region exceeding the saturated luminance Bs and an unsaturated region below the saturated luminance Bs from a plurality of partial regions, respectively, and a saturated luminance region list and an unsaturated region arranged in descending order and ascending order of the luminance Bp, respectively. Create each list.

  When the total number of saturated regions included in the saturated region list is smaller than the total number of unsaturated regions included in the unsaturated region list, the plurality of unsaturated regions included in the unsaturated region list so that the total number is the same. , An unsaturated region having a low luminance Bp is added to the end of the unsaturated region list. The position of each of the saturated area and the unsaturated area is the partial area located in the lower left of the captured image among the partial areas divided in a matrix, and the origin (1, 1) is the origin, and the X and Y coordinates are the origin. To XY coordinates expressed in the order of partial areas arranged in the horizontal direction and the order of partial areas arranged in the vertical direction. For example, the coordinates of the saturated region 172a and the unsaturated region 172b shown in FIG. 18A are the coordinates (4, 2) and the coordinates (1, 4), respectively.

The strobe lighting device 1 associates each saturated region included in the saturated region list with each unsaturated region included in the unsaturated region list on a one-to-one basis according to the order in the list. Relative coordinates (Xr, Yr) of the coordinates (X2, Y2) of the unsaturated region with the coordinates (X1, Y1) of the saturated region as the reference coordinates in each of the associated saturated region and unsaturated region pair are as follows: Is calculated using
(Xr, Yr) = (X2-X1, Y2-Y1) (6)
When the saturated region 172a and the unsaturated region 172b are associated with each other in the example shown in FIG. 18A, relative coordinates (4, 2) and (1, 4) from the coordinates (4, 2) and (1, 4) of the saturated region 172a and the unsaturated region 172b, respectively. −3, +2) is calculated.

  FIG. 19 is a table showing a data example of the light distribution determination table 203 according to the third embodiment. In the light distribution determination table 203, the X direction component and the Y direction component of the irradiation angle θ associated with the X coordinate Xr and the Y coordinate Yr of the relative coordinates (Xr, Yr), respectively, the angle component θx and the angle component θy, respectively. Is remembered. In the example shown in FIG. 19, in the light distribution changing unit 15 composed of a total of 40 liquid crystal lenses of 8 horizontal and 5 vertical, the X coordinate Xr has a value from −6 to +6 and the Y coordinate Yr has −4 to +4. The value of the angle component θx from −30 ° to + 30 ° and the value of the angle component θy from −20 ° to + 20 ° are stored in association with each of the above values. The light distribution determination table 203 may be obtained in advance by the configuration of the light distribution changing unit 15 and stored in the ROM 20.

  The strobe lighting device 1 reads the angle component θx and the angle component θy corresponding to the relative coordinates (Xr, Yr) from the light distribution determination table 203. The strobe lighting device 1 sets the light distribution control unit 16 so that the irradiation angle θ of the liquid crystal lens corresponding to the saturation region becomes the angle component θx and the angle component θy read from the light distribution determination table 203. The light distribution control unit 16 applies a voltage so that the irradiation angle of the corresponding liquid crystal lens among the plurality of liquid crystal lenses forming the light distribution change unit 15 becomes the set angle component θx and the angle component θy, and distributes the light. change. As a result, the light flux of the strobe light that irradiates the saturated region where the high luminance Bf is calculated in the associated saturated region and unsaturated region pair is equal to or less than the luminance Bs, and the unsaturated region where the low luminance Bf is calculated. The irradiation angle of the liquid crystal lens corresponding to the saturation region is changed so as to go to.

  In the example shown in FIG. 18B, the irradiation direction L1c of the strobe light that passes through the liquid crystal lens 15c and irradiates a part of the illuminated object 102 located in the saturated region 172a in the pre-light emission is directed toward the unsaturated region 172b. The irradiation direction is changed to L2c. Under the main light emission, the unsaturated region 172b is irradiated with a light beam passing through the liquid crystal lens 15c whose irradiation angle is changed and a light beam passing through the liquid crystal lens 15d whose irradiation angle is not changed.

The luminance Bp of the saturated region and the unsaturated region corresponding to the saturated region are updated to the luminance Bp1 and the luminance Bp2 calculated according to the following equations, respectively.
Bp1 = Bn− (Bp−Bn) · k2 (7)
Bp2 = Bn + (Bp−Bn) · k3 (8)
Here, k2 and k3 are proportional constants, and may be obtained and stored in advance based on the optical characteristics of a plurality of liquid crystal lenses forming the light distribution changing unit 15. The strobe lighting device 1 executes the main light emission setting process based on the luminance Bn under no light emission and the luminance Bp under the pre-light emission including the luminance Bp1 and Bp2 updated by the light distribution change processing, and emits the main light emission amount If. Set in the quantity control unit 12.

  FIG. 20 is a flowchart illustrating a procedure of light emission processing executed by the strobe lighting device 1 according to the third embodiment. The CPU 11 determines whether or not the operation reception unit 18 has received a light emission operation instructing to emit strobe light (step S101). When it is determined that the light emission operation has not been accepted (NO in step S101), the CPU 11 returns the process to step S101 for determining whether or not the light emission operation has been accepted. If the CPU 11 determines that the light emission operation has been accepted (YES in step S101), the CPU 11 executes multi-photometry processing (step S102). The CPU 11 executes an after-mentioned light distribution changing process for changing the light distribution of the strobe light by determining the irradiation angle of each of the plurality of liquid crystal lenses forming the light distribution changing unit 15 and setting the irradiation angle in the light distribution control unit 16 (step). S103).

  The CPU 11 performs a main light emission amount setting process in which the main light emission amount is determined based on the luminance Bn and the luminance Bp of each partial region updated from the irradiation angle set by the light distribution changing process and set in the light emission amount control unit 12. Execute (Step S104). The CPU 11 causes the light emission amount control unit 12 to perform main light emission from the strobe light source 14 via the drive power supply 13 (step S105). The CPU 11 determines whether or not the power has been turned off by detecting a power off signal that is output when a power switch (not shown) provided in the strobe lighting device is disconnected (step S106). If the CPU 11 determines that the power is not turned off (NO in step S106), the CPU 11 returns the process to step S101 for determining whether or not a light emission operation has been accepted. If the CPU 11 determines that the power has been turned off (YES in step S106), the light emission process ends.

  FIGS. 21 and 22 are flowcharts showing the procedure of the light distribution change process according to the third embodiment. The CPU 11 reads the saturated luminance Bs stored in the ROM 20 (step S111). CPU11 extracts the saturation area | region which has the brightness | luminance Bp exceeding the saturation brightness | luminance Bs (step S112). The CPU 11 creates a saturated region list in which the extracted saturated regions are arranged in descending order of the luminance Bp (step S113). CPU11 extracts the unsaturated area | region which has the brightness | luminance Bp below the saturation brightness | luminance Bs (step S114). The CPU 11 creates an unsaturated area list in which the extracted unsaturated areas are arranged in ascending order of the luminance Bp (step S115). The CPU 11 determines whether or not the total number of extracted saturated regions is larger than the total number of extracted unsaturated regions (step S116).

  If the CPU 11 determines that there are many (YES in step S116), an unsaturated region having a low luminance Bp positioned higher in the unsaturated region list so as to be equal to the total number of saturated regions is placed at the end of the unsaturated region list. It adds (step S117). The CPU 11 sets 1 to the counter C (step S118). The CPU 11 calculates the relative coordinates (Xr, Yr) of the C-th unsaturated region in the unsaturated region list with respect to the C-th saturated region in the saturated region list using Equation (6) (step S119). The CPU 11 reads the irradiation angle (θx, θy) corresponding to the calculated relative coordinates (Xr, Yr) from the light distribution determination table 203 (step S120). The CPU 11 controls the light distribution control unit 16 so that the irradiation angle of the liquid crystal lens corresponding to the C-th saturation region among the plurality of liquid crystal lenses constituting the light distribution changing unit 15 becomes the read irradiation angle (θx, θy). Setting is performed (step S121).

  The CPU 11 updates the brightness Bp of each of the Cth saturated region and the Cth unsaturated region to the values of the brightness Bp1 and the brightness Bp2 calculated using the expressions (7) and (8), respectively (step S122). . The CPU 11 increments the counter C (step S123). The CPU 11 determines whether or not the counter C exceeds the total number of saturated areas included in the saturated area list (step S124). If the CPU 11 determines that it does not exceed (NO in step S124), the relative coordinate (Xr, Yr) of the Cth unsaturated region in the unsaturated region list with respect to the Cth saturated region in the saturated region list is expressed by the equation (6). The processing is returned to step S119 calculated by (1). If the CPU 11 determines that it has exceeded (YES in step S124), it ends the light distribution change process. If the CPU 11 determines in step S116 that it is determined whether or not the total number of extracted saturated regions is larger than the total number of extracted unsaturated regions (NO in step S116), the CPU 11 sets 1 to the counter C. The process moves to step S118.

  The strobe illuminating device 1 changes the light distribution from a saturated region extracted in pre-emission of strobe light to an unsaturated region, and assigns a part of the strobe light that illuminates the saturated region to an unsaturated region with low luminance, thereby providing a strobe light source. The light distribution is adjusted without causing any loss in the strobe light emitted by the light source 14. In the present embodiment, the case where the plurality of liquid crystal lenses forming the light distribution changing unit 15 is arranged in a matrix, that is, a tetragonal lattice shape is shown, but a hexagonal lattice shape or the like may be used. . Moreover, although the case where it changed so that the light beam which goes to a saturation area may go to an unsaturated area was shown, not only this but the light beam which goes to the high-intensity area | region which has the brightness | luminance exceeding a preset upper limit threshold value is set to the preset lower limit You may make it change so that it may go to the low-intensity area | region which has the brightness | luminance below a threshold value.

  In the third embodiment, the case where the light distribution changing unit 15 is composed of 40 liquid crystal lenses arranged in a matrix of 8 horizontal and 5 vertical is shown. However, the present invention is not limited to this and is less than 40. The light distribution changing unit 15 may be composed of 40 or more liquid crystal lenses.

  The third embodiment is configured as described above, and the other configurations and operations are the same as those of the first embodiment. Therefore, the corresponding parts are denoted by the same reference numerals and processing names, and detailed description thereof is omitted. To do.

Embodiment 4
In the present embodiment, the light distribution changing unit 15 is configured from a plurality of liquid crystal elements and the light distribution adjustment is performed by controlling the transmittance of each of the plurality of liquid crystal elements. The light distribution changing unit 15 is configured from the lens, and the light distribution adjustment is performed by controlling the focal length of each of the plurality of liquid lenses. The light distribution control unit 16 changes the voltage applied to each of the plurality of liquid lenses constituting the light distribution changing unit 15 based on the set focal length, and controls the focal length of each liquid lens to adjust the light distribution. It is configured as follows. The strobe lighting device 1 is configured to adjust the light distribution of the strobe light by performing multi-photometry processing, setting the main light emission of the strobe light, and changing the light distribution of the strobe light before executing the main light emission.

  In the multi-photometry process according to the first embodiment, substantially the same maximum transmittance is set in the light distribution control unit 16 for all of the plurality of liquid crystal elements forming the light distribution changing unit 15, but the multi-photometry process according to the present embodiment is performed. In the photometric process, a predetermined focal length substantially the same for all of the plurality of liquid lenses constituting the light distribution changing unit 15 is set in the light distribution control unit 16. Luminance Bn and luminance Bp under non-light emission and pre-light emission are acquired by multi-photometry processing. The strobe lighting device 1 reads the lower limit luminance Bt under pre-emission stored in advance in the ROM 20, reads out the emission amount corresponding to the ratio Ra calculated using the equation (1) from the emission amount determination table 202, and performs the main emission. The amount If is set in the light emission amount control unit 12. Next, the light distribution adjustment of strobe light by controlling the focal length of the liquid lens will be described.

  FIG. 23 is a schematic diagram illustrating divided captured images and strobe light fluxes according to the fourth embodiment. FIG. 23 shows the captured image under pre-emission divided into a plurality of partial regions and the strobe light flux whose focal length is changed by the liquid lens, arranged in the order of (a) and (b). A white arrow in FIG. 23B indicates a vertical direction with respect to the front surface of the light distribution changing unit 15. L3 and L4 in FIG. 23B indicate light beams before and after changing the focal length of the strobe light that passes through one liquid lens 15e among the plurality of liquid lenses forming the light distribution changing unit 15. The horizontal width of the light distribution changing unit 15 is shown to correspond to the horizontal width of the captured image 173, and the human image captured in the captured image 173 corresponds to the illuminated object 103. The light beam L3 passing through the liquid lens 15e illuminates the saturation region 173a.

  In the example shown in FIG. 23A, the captured image 173 has 40 partial areas corresponding to 40 liquid lenses arranged in a matrix of 8 horizontal and 5 vertical that form the light distribution changing unit 15. Is divided. The stroboscopic illumination device 1 predicts the brightness of each partial region when the stroboscopic light having the main light emission amount If is applied to all the liquid lenses constituting the light distribution changing unit 15 with substantially the same predetermined focal length set. Bf is calculated by equation (2). The strobe lighting device 1 extracts a saturated region in which a luminance Bf that is equal to or higher than the saturated luminance Bs is calculated. The strobe lighting device 1 extracts the luminance Bn of the partial region corresponding to the saturated region, and uses the equation (3) to calculate the ratio Rb based on the saturated luminance Bs, the luminance Bf that is equal to or higher than the saturated luminance Bs, and the extracted luminance Bn. calculate.

  The strobe lighting device 1 reads the focal length associated with the ratio Rb in the light distribution determination table 203, and among the plurality of liquid lenses forming the light distribution changing unit 15, the focal length of the liquid lens corresponding to the saturation region. Is set in the light distribution control unit 16 so as to be the focal length read from the light distribution determination table 203. In the example shown in FIG. 23B, the strobe light beam L3 that passes through the liquid lens 15e in the pre-light emission and irradiates a part of the illuminated object 103 located in the saturation region 173a is the focal length of the liquid lens 15e. Has been changed to a light beam L4 in which the light flux is spread by being displaced by ΔZ and the light intensity density on the irradiated surface is reduced. The strobe lighting device 1 adjusts the light distribution without causing any loss in the strobe light emitted from the strobe light source 14 by changing the focal length and controlling the light amount density of the strobe light that irradiates the saturated region.

  FIG. 24 is a table illustrating a data example of the light distribution determination table 203 according to the fourth embodiment. The light distribution determination table 203 stores displacement amounts ΔZ of a plurality of focal lengths respectively associated with a plurality of values of the ratio Rb. In the example shown in FIG. 24, the displacement amount ΔZ of the focal length from 0 m to 0.6 m is stored in association with each value of the ratio Rb from 1 to 0.2. As the value of the ratio Rb decreases, the luminance Bp of the saturation region greatly exceeds the saturation luminance Bs. Therefore, the focal length displacement amount ΔZ is set so as to widen the strobe light by setting a long focal length and reduce the light amount density. The ratio Rb and the focal length displacement ΔZ are stored in the light distribution determination table 203 so as to increase. The ratio Rb and the displacement ΔZ of the focal distance may be obtained empirically in advance and stored in the light distribution determination table 203. The strobe lighting device 1 reads from the light distribution determination table 203 the focal length displacement amount ΔZ corresponding to the ratio Rb calculated for each partial region. The strobe lighting device 1 changes the focal length of the liquid lens corresponding to the saturation region among the plurality of liquid lenses forming the light distribution changing unit 15 according to the focal length displacement amount ΔZ read from the light distribution determination table 203. Set in the light distribution control unit 16.

  When the same value as the ratio Rb is not recorded in the light distribution determination table 203, the displacement of the focal length is complemented based on a predetermined function from the focal length displacement amount ΔZ respectively associated with the preceding and succeeding values. The amount ΔZ may be obtained. After adjusting the light distribution by setting the main light emission amount and the focal length, the strobe lighting device 1 causes the light emission amount control unit 12 to supply power to the strobe light source 14 via the drive power supply 13 to cause the strobe light source to perform main light emission. . The strobe light emitted from the strobe light source 14 by the main light emission passes through each liquid lens forming the light distribution changing unit 15 whose focal length is controlled, the light distribution is adjusted, and the illuminated object is irradiated in the illumination range.

  FIG. 25 is a flowchart illustrating a procedure of light distribution change processing according to the fourth embodiment. The CPU 11 calculates the luminance Bf of each partial region predicted under the main light emission using the equation (2) (step S131). The CPU 11 reads the saturated luminance Bs stored in the ROM 20 (step S132). The CPU 11 extracts a partial region where the luminance Bf exceeding the saturated luminance Bs is calculated, that is, a saturated region, from among the partial regions where the luminance Bf is calculated (step S133). CPU11 extracts the brightness | luminance Bn acquired from the partial area | region corresponding to a saturation area | region among the some brightness | luminance Bn under non-light-emission acquired by the multiphotometry process (step S134).

  The CPU 11 calculates the ratio Rb of each partial region using Expression (3) (Step S135). The CPU 11 reads the displacement ΔZ of the focal length associated with the ratio Rb in the light distribution determination table 203 stored in the ROM 20 (Step S136). The CPU 11 sets the focal length at which the liquid lens corresponding to the saturation region among the plurality of liquid lenses constituting the light distribution changing unit 15 becomes the read focal length displacement amount ΔZ in the light distribution control unit 16 (step S137). ), The light distribution of the strobe light is changed, and the light distribution change process is terminated.

  In the present embodiment, the case where the light distribution adjustment is performed by controlling the focal length of each of the plurality of liquid lenses that form the light distribution changing unit 15 is described, but the light distribution changing unit 15 is configured from a plurality of liquid crystal lenses, Light distribution adjustment may be performed by controlling the focal length of each of the plurality of liquid crystal lenses. Moreover, although the case where the light distribution changing unit 15 is composed of 40 liquid lenses arranged in a matrix of 8 horizontal and 5 vertical is shown, the present invention is not limited to this, and less than 40 and 40 or more liquids are shown. The light distribution changing unit 15 may be a lens.

  The fourth embodiment is configured as described above, and the other configurations and operations are the same as those of the first embodiment. Therefore, the same reference numerals and processing names are assigned to the corresponding parts, and detailed description thereof is omitted. To do.

Embodiment 5
26 and 27 are a schematic perspective view showing the appearance of the strobe light emitting portion according to the fifth embodiment, and a structural sectional view taken along the line XXVII-XXVII in FIG. In the present embodiment, the strobe light emitting unit 22 according to the first embodiment adjusts the light distribution of the strobe light emitted from the xenon lamp, whereas the strobe light emitted from a plurality of LEDs arranged in a two-dimensional matrix. It is configured to adjust the light distribution. The strobe light source 14 is arranged in a matrix within a rectangular parallelepiped housing 141 having a rectangular opening, and a plurality of LEDs 144, 144,... That emit strobe light and LEDs 144, 144,. The substrate 145 includes a heat sink 146 provided on the back surface of the substrate 145.

  The light distribution changing unit 15 includes a plurality of liquid crystal elements corresponding to the plurality of LEDs 144, 144,... Arranged in a matrix. The heat generated by the LED 144 is radiated to the atmosphere by the heat radiating plate 146 through the substrate 145. The strobe light emitted from the LEDs 144, 144,... Is incident on each of a plurality of two-dimensionally arranged liquid crystal elements forming the light distribution changing unit 15, and is attenuated according to the transmittance set for each liquid crystal element. The light distribution is adjusted. When the operation accepting unit 18 accepts an adjustment operation instructing the adjustment of the strobe light by the user, the strobe lighting device 1 performs the multi-photometry processing before executing the main light emission of the strobe light, and then performs the main light of the strobe light. Adjust the light distribution by setting the flash output and changing the flash light. The strobe lighting device 1 is configured to repeat the light distribution adjustment of the strobe light until the operation receiving unit 18 receives a main light emission operation instructing the main light emission of the strobe light whose light distribution has been adjusted.

  FIG. 28 is a flowchart showing a procedure of light emission processing executed by the strobe lighting device according to the fifth embodiment. The CPU 11 determines whether or not the operation receiving unit 18 has received an adjustment operation for instructing the light distribution adjustment of the strobe light (step S141). When it is determined that the adjustment operation has not been received (NO in step S141), the CPU 11 returns the process to step S141 for determining whether the adjustment operation has been received. If it is determined that the adjustment operation has been received (YES in step S141), the CPU 11 executes multi-photometry processing for acquiring the luminance Bn and the luminance Bp (step S142). The CPU 11 executes a main light emission amount setting process that determines the main light emission amount based on the acquired luminance Bn, luminance Bp, and the like and sets the light emission amount control unit 12 (step S143). The CPU 11 determines the transmittance based on the luminance Bn, the luminance Bp, and the like, sets the transmittance in the light distribution control unit 16, and executes a light distribution changing process for changing the light distribution of the strobe light (step S144).

  The CPU 11 determines whether or not a main light emission operation instructing the main light emission of the strobe light source 14 has been received (step S145). If it is determined that the main light emission operation has not been accepted (NO in step S145), the CPU 11 returns the process to step S142 in which the multi-photometry process is executed. When the CPU 11 determines that the main light emission operation has been received (YES in step S145), the light emission amount control unit 12 causes the flash light source 14 to perform main light emission via the drive power supply 13 (step S146). The CPU 11 determines whether or not the power is turned off by detecting a power-off signal output when a power switch (not shown) provided in the strobe lighting device 1 is disconnected (step S147). When determining that the power is not turned off (NO in step S147), the CPU 11 returns the process to step S141 for determining whether or not the light emission operation is accepted. If the CPU 11 determines that the power has been turned off (YES in step S147), the light emission process ends.

  In the present embodiment, the case where the light distribution changing unit 15 includes a plurality of liquid crystal elements corresponding to the LEDs 144, 144,... Is not limited to this, and the light distribution changing unit 15 is not limited to the LED 144, 144,... Are divided into a plurality of light distribution change areas each made up of a plurality of liquid crystal elements, and a plurality of images corresponding to the plurality of light distribution change areas in one-to-one correspondence in the multi-light measurement process. It may be divided into partial areas. In this case, the light distribution control unit 16 sets the transmittance for each of the plurality of light distribution change regions, and sets substantially the same transmittance as the transmittance of the plurality of liquid crystal elements forming the light distribution change region. Configure. Moreover, although the case where the light distribution change part 15 consists of a some liquid crystal element was shown, the case where it consists of a some liquid crystal lens or liquid lens corresponding to each of LED144,144, ... may be sufficient.

  The fifth embodiment is configured as described above, and the other configurations and operations are the same as those of the first to fourth embodiments. Therefore, the same reference numerals and processing names are assigned to corresponding parts. Detailed description thereof is omitted.

Embodiment 6
FIG. 29 is a flowchart showing a procedure of the main light emission amount setting process according to the sixth embodiment. In the present embodiment, each of the plurality of LEDs according to the fifth embodiment is adjusted to approximately the same light emission amount, whereas the light emission amount of each of the plurality of LEDs is adjusted. The light emission amount control unit 12 is configured to control the plurality of LEDs 144, 144,... Constituting the strobe light source 14 via the drive power supply 13 so that the light emission amount is set to each.

  The CPU 11 extracts the luminance Bp under the pre-light emission of each partial area acquired by the above-described multi-photometry process (step S151). The CPU 11 extracts the luminance Bn under no light emission of each partial area acquired by the multi-photometry process (step S152). The CPU 11 reads the lower limit luminance Bt stored in advance in the ROM 20 (step S153). The CPU 11 calculates the ratio Ra of each partial region using Expression (1) (step S154). The CPU 11 reads out the light emission amounts associated with the ratio Ra of each partial area in the light emission amount determination table 202 stored in the ROM 20 (step S155). The CPU 11 sets the light emission amount read in correspondence with the ratio Ra of each partial region to the light emission amount control unit 12 as the main light emission amount If of each of the LEDs 144, 144,... Corresponding to each partial region (step S156). The light emission amount setting process ends.

  The sixth embodiment has the above-described configuration, and the other configurations and operations are the same as those in the first to fifth embodiments. Therefore, corresponding parts are denoted by the same reference numerals and processing names. Detailed description thereof is omitted.

Embodiment 7
FIG. 30 is a block diagram illustrating an internal hardware configuration of an imaging apparatus including the strobe lighting device according to the seventh embodiment. In the figure, reference numeral 4 denotes an image pickup apparatus. The image pickup unit 47 picks up an image pickup object illuminated by strobe light, and the storage medium writing unit 42 writes the picked-up image picked up by the image pickup unit 47 into a storage medium (not shown). And an operation accepting unit 48 that accepts an operation on the imaging device by a user, an imaging control unit 41 as a control unit, and a ROM 40 that stores various data including an imaging control program 401. The imaging control unit 41 is connected to each hardware unit of the imaging device 4 via the bus 21, controls each hardware unit, and reads and executes the imaging control program 401 stored in the ROM 40 in the RAM 19. Then, various software processes are executed. The imaging unit 47 is configured to capture an illumination range under no light emission and under pre-light emission when the imaging device 4 adjusts the light distribution of the strobe light.

  When the operation accepting unit 48 accepts an imaging operation for instructing imaging of an object to be imaged under the strobe light illumination light, the imaging control unit 41 reads out the flash control program 201 stored in the ROM 40 to the RAM 19 and executes it. An object to be imaged is captured under the main emission of strobe light with adjusted light. This prevents the occurrence of an overexposed portion that exceeds saturation luminance and an underexposed portion that has insufficient luminance in a captured image obtained by capturing an image of an object under strobe light. In addition, since the luminance distribution in the captured image is within a certain range, an inexpensive element having a narrow dynamic range can be used as the image receiving element such as a CCD used in the imaging unit 47.

  The seventh embodiment has the above-described configuration, and the other configurations and operations are the same as those in the first to sixth embodiments. Therefore, corresponding parts are denoted by the same reference numerals and detailed description thereof is omitted. Description is omitted.

3 is a block diagram showing an internal hardware configuration of the strobe lighting device according to Embodiment 1. FIG. It is a typical perspective view which shows a strobe light emission part. It is typical structure sectional drawing in the III-III line of FIG. 6 is a schematic diagram illustrating an example of a captured image under pre-emission and a divided captured image according to Embodiment 1. FIG. It is a table | surface which shows the example of data of the light emission amount determination table | surface. 4 is a table illustrating an example of data of a light distribution determination table according to Embodiment 1. 4 is a flowchart showing a procedure of light emission processing executed by the strobe lighting device according to the first embodiment. It is a flowchart which shows the procedure of a multiphotometry process. 3 is a flowchart showing a procedure of a main light emission amount setting process according to the first embodiment. 4 is a flowchart illustrating a procedure of light distribution change processing according to the first embodiment. 6 is a block diagram showing an internal hardware configuration of a strobe lighting device according to Embodiment 2. FIG. 6 is a table showing an example of data of a light distribution determination table according to Embodiment 2. 6 is a flowchart showing a procedure of light emission processing executed by the strobe lighting device according to the second embodiment. It is a flowchart which shows the procedure of a photometry process. 10 is a flowchart showing a procedure of main light emission amount setting processing according to the second embodiment. It is a flowchart which shows the procedure of a ranging process. 10 is a flowchart illustrating a procedure of light distribution change processing according to the second embodiment. FIG. 10 is a schematic diagram illustrating divided captured images and strobe light fluxes according to Embodiment 3. 10 is a table illustrating an example of data of a light distribution determination table according to Embodiment 3. 12 is a flowchart illustrating a procedure of light emission processing executed by the strobe lighting device according to the third embodiment. 10 is a flowchart illustrating a procedure of light distribution change processing according to the third embodiment. 10 is a flowchart illustrating a procedure of light distribution change processing according to the third embodiment. FIG. 10 is a schematic diagram illustrating divided captured images and strobe light fluxes according to Embodiment 4. 10 is a table illustrating an example of data of a light distribution determination table according to Embodiment 4. 14 is a flowchart illustrating a procedure of light distribution change processing according to the fourth embodiment. FIG. 10 is a schematic perspective view showing an appearance of a strobe light emitting unit according to a fifth embodiment. FIG. 27 is a structural cross-sectional view taken along line XXVII-XXVII in FIG. 26. 10 is a flowchart showing a procedure of light emission processing executed by the strobe lighting device according to the fifth embodiment. 18 is a flowchart illustrating a procedure of main light emission amount setting processing according to the sixth embodiment. FIG. 20 is a block diagram illustrating an internal hardware configuration of an imaging apparatus including a strobe lighting device according to a seventh embodiment.

Explanation of symbols

1 Strobe lighting device 11 CPU
DESCRIPTION OF SYMBOLS 12 Light emission amount control part 13 Drive power supply 14 Strobe light source 15 Light distribution change part 15c, 15d Liquid crystal lens 15e Liquid lens 16 Light distribution control part 17 Imaging part 18 Operation reception part 19 RAM
20 ROM
21 Bus 31 Light receiving sensor 32 Distance sensor 47 Imaging unit 201 Strobe control program 202 Light emission amount determination table 203 Light distribution determination table 401 Imaging control program

Claims (12)

Comprising a light source, a plurality of light distribution changing elements arranged two-dimensionally, a light distribution changing unit for changing the light distribution of the illumination light emitted from the light source, and an imaging unit for imaging the illumination range of the illumination light In the light distribution adjustment method of the illumination light emitted by the illumination device,
The imaging range of the illumination light is captured by the imaging unit to obtain a captured image,
Obtaining brightness of a plurality of partial areas corresponding to each of the plurality of light distribution change elements from the captured image;
A light distribution adjustment method, wherein an optical parameter of each of the plurality of light distribution change elements is controlled based on the luminance. A light source and a plurality of light distribution changing elements arranged two-dimensionally, a light distribution changing unit for changing the light distribution of the illumination light emitted from the light source, and an object to be illuminated located in the illumination range of the illumination light In the light distribution adjustment method of the illumination light emitted by the illumination device including the distance measuring unit for measuring the distance,
The distance from the light source to the object to be illuminated located in the illumination range is measured by the distance measuring unit,
A light distribution adjustment method, wherein the optical parameter of each of the plurality of light distribution changing elements is changed based on the distance. A light source and a plurality of light distribution changing elements arranged two-dimensionally, a light distribution changing unit for changing the light distribution of the illumination light emitted from the light source, and an object to be illuminated located in the illumination range of the illumination light Distribution of illumination light emitted by an illumination device including a distance measuring unit that measures a distance, a luminance acquisition unit that acquires the luminance of the illumination range of the illumination light, and an imaging unit that images the illumination range of the illumination light In the adjustment method,
The distance from the light source to the object to be illuminated located in the illumination range is measured by the distance measuring unit,
The light distribution adjustment method, wherein the light emission amount of the light source and the optical parameters of each of the plurality of light distribution changing elements are changed based on the luminance and the distance, respectively. A light source change comprising a light source composed of a plurality of light emitting elements arranged two-dimensionally and a plurality of light distribution changing elements corresponding to the plurality of light emitting elements, and changing the light distribution of illumination light emitted from the light source In the light distribution adjustment method of the illumination light irradiated by the illumination device including the imaging unit that images the illumination range of the illumination light, and
The imaging range of the illumination light is captured by the imaging unit to obtain a captured image,
Obtaining brightness of a plurality of partial areas corresponding to each of the plurality of light emitting elements from the captured image;
A light distribution adjustment method, wherein an optical parameter of each of the plurality of light distribution change elements is changed based on the luminance.   The light distribution adjustment method according to claim 1, wherein the light emission amount of the light source is changed based on the luminance.   The light distribution adjustment method according to claim 4, wherein the light emission amount of each of the plurality of light emitting elements is changed based on the luminance. An illumination device that includes a light source and a light distribution changing unit that is disposed on a front side of the light source and changes a light distribution of illumination light incident on a rear surface from the light source, and adjusts and distributes the light distribution of the illumination light In
The light distribution change unit is composed of a plurality of light distribution change elements arranged two-dimensionally,
An imaging unit for imaging an illumination range of the illumination light;
A luminance acquisition unit that acquires luminance of a plurality of partial areas corresponding to each of the plurality of light distribution change elements from a captured image captured by the imaging unit;
An illumination device, comprising: a light distribution control unit that controls an optical parameter of each of the plurality of light distribution change elements based on the respective luminances acquired by the luminance acquisition unit. A high-intensity area detection unit that detects a high-intensity area that has a threshold value and has a luminance that exceeds the threshold value from the captured image;
The said light distribution control part is comprised so that the optical parameter of each light distribution change element corresponding to the said high-intensity area | region among these light distribution change elements may be controlled. Lighting equipment. The light distribution changing element is a liquid crystal element with variable transmittance,
The lighting device according to claim 7 or 8, wherein the light distribution control unit is configured to control transmittance of each of the plurality of liquid crystal elements. The light distribution changing element is composed of a liquid crystal lens with variable irradiation angle,
The lighting device according to claim 7 or 8, wherein the light distribution control unit is configured to control an irradiation angle of each of the plurality of liquid crystal lenses. The light distribution changing element is composed of a variable focal length liquid lens,
The lighting device according to claim 7 or 8, wherein the light distribution control unit is configured to control a focal length of each of the plurality of liquid lenses.   An imaging apparatus comprising the illumination device according to any one of claims 7 to 11.

Images