JP2006269293A - Lighting system and lighting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To eliminate irregularity of white balance and irregularity of luminance in an imaged image, in a document presentation device. <P>SOLUTION: In a structure used for imaging a document 106 mounted on a document mounting base 104 of a document presentation device 101 by an imaging device 102 and for projecting the image thereof on a projection screen 123, irregularity of brightness on the document mounting base 104 and irregularity of color of light are previously detected, and a light emission amount distribution and RGB balance of illumination from this lighting system 108 are adjusted based on the detection result thereof. Thus, irregularity of brightness and irregularity of color are prevented from being generated in the imaged image by influence of light from the lighting system 108 and light from a luminaire 124. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an illuminating device used for a material presentation device used when a presentation or education using an image is performed.

  There is a known method of projecting materials such as charts on a screen and giving a presentation while pointing to it. This technique is often used in meetings and classes. In this method, a material presentation device is used as a device for imaging a material.

  The basic function of the material presentation device is to image the set material with an imaging device. The captured image is projected on a screen, and a presentation is performed while showing the projected image to the viewer. Generally, when a presentation is performed, the room is darkened to some extent in order to make the projected image easy to see. However, since the material set in the material presentation device is an object to be imaged, it is necessary to apply a certain amount of light using auxiliary lighting.

  Regarding this technique, for example, the technique described in Patent Document 1 is known. Patent Document 1 describes a technique related to a technique for solving luminance unevenness due to an illumination light source that applies illumination light to a document. Here, a technique for detecting nonuniform luminance from an image obtained by capturing a document and correcting the nonuniform luminance in the image by image processing is described. In addition, a configuration is described in which non-uniform luminance is detected from a captured image and the amount of light emitted from the lighting device is reduced when the luminance unevenness is large.

JP 2004-214714 A

  In general, the venue where presentations are held is not completely dark, but is bright enough for viewers to take notes or view materials. There are also cases where a presentation is given in a situation where there is light entering through a window. In such a case, the brightness of the venue (for example, room lighting) is added to the material to be imaged in addition to the illumination provided in the material presentation device.

  At this time, two problems occur. One of the problems is that uneven brightness occurs in the captured image due to the balance between the lighting in the hall (or the light inserted through the window, etc.) and the lighting provided in the material presentation device.

  Another problem is that uneven color (uneven white balance) occurs in the material to be imaged when the spectral distributions of the illumination in the venue and the illumination of the material presentation device are different.

  For example, this problem occurs when the illumination provided in the material presentation device is white light by an LED and the illumination in the venue is an incandescent lamp (light bulb). In this case, by irradiating irradiation light with different RGB balance, the imaging target partially exhibits different shades, and it is difficult to adjust the white balance of the imaging system. In this case, it is difficult to adjust the white balance uniformly, resulting in a state in which the hue varies depending on the location.

  The technique described in Patent Document 1 is a technique that attempts to correct luminance unevenness in a captured image by image processing. However, correcting image unevenness in addition to luminance unevenness by image processing is a normal image. The current situation is that it is heavy to carry out by processing, and it is difficult to make sufficient corrections.

  Japanese Patent Application Laid-Open No. 2004-228561 describes control for adjusting the light emission amount of the illumination light source in accordance with the unevenness of luminance, but the luminance changes as a whole only by adjusting the light emission amount of the illumination light source. Therefore, it is impossible to fundamentally improve the above-described non-uniform luminance and non-uniform hue.

  It is an object of the present invention to provide a technique capable of effectively improving unevenness in luminance and unevenness in color in a captured image when capturing an image using a material presenting apparatus.

  The illumination device of the present invention includes an illumination unit that irradiates an imaging target with illumination light, an illumination control unit that controls the illumination unit, and an illumination light characteristic analysis that detects RGB balance and luminance distribution in the captured image of the imaging target. And the illumination control means has a function of adjusting an RGB balance of illumination with respect to the imaging target and further partially adjusting a light emission amount of illumination with respect to the imaging target.

  In this specification, luminance refers to the amount of light that is reflected by an object and enters the human eye (or a suitable light detection element). In other words, the luminance refers to the amount of reflected light reflected from the imaging target.

  According to the present invention, since the illumination on the imaging target takes into account the RGB balance and the luminance distribution, it is possible to effectively improve the luminance unevenness and the color unevenness in the captured image. That is, in the present invention, when an imaging target illuminated by illumination (for example, indoor illumination is included in this illumination), white balance unevenness due to location does not occur in the captured image. Adjust the RGB balance of the illumination light. Simultaneously with the adjustment of the RGB balance, the illumination is adjusted to a light emission distribution that cancels the uneven luminance. By doing so, it is possible to suppress uneven white balance and uneven brightness in the captured image.

  In the present invention, the illumination means is an array light source in which three RGB light sources are arranged in a matrix, and the RGB balance is adjusted by individually adjusting the light emission amounts of the three RGB light sources. It is preferable that the light emission amount is partially adjusted by adjusting the light emission distribution.

  In this embodiment, there can be mentioned a structure in which light sources each having a structure in which LEDs for emitting RGB are combined in one package are arranged in one or a plurality of columns. According to this aspect, by independently adjusting the RGB light sources, the distribution state of the emission spectrum can be adjusted, and the RGB balance of the illumination light can be adjusted. Further, the intensity distribution of the illumination light on the irradiated surface can be adjusted by adjusting the light emission intensity distribution of the RGB light sources (a set of RGB light sources is defined as an RGB light source) arranged in an array. That is, it is possible to create irradiation light that is strong and weak depending on a place such that a certain portion of the irradiated surface is strongly irradiated with light and the other portion is irradiated with light weakly.

  By using the illumination means of this aspect, it is possible to apply light that is partially intensified to the imaging target, thereby preventing luminance nonuniformity from occurring in an image obtained by imaging the imaging target. That is, in such an illuminating device, when the illumination is normally applied, if the brightness non-uniformity is seen in the captured image, the irradiation light has a strong and weak distribution that cancels the non-uniformity. Can be intentionally produced.

  It should be noted that the adjustment of the RGB balance is easy to perform simultaneously for all the RGB light sources, but may be performed individually. When the RGB balance is adjusted with an individual RGB light source, the distribution state of the RGB balance on the irradiated surface can be adjusted.

  In the present invention, it is preferable to adjust the white balance in an environment in which the illumination unit is turned off. In this case, the white balance is adjusted based on the image captured in the brightness with the illumination unit turned off. According to this aspect, the RGB balance of the light emitted from the illumination unit is matched to the RGB balance of the brightness of the environment, so that light of different RGB balance is applied to the imaging target, and the color tone of the captured image is partially mottled Such inconvenience is prevented.

  Hereinafter, the operation of this aspect will be specifically described. Here, a case where a presentation is performed using a material presentation device including a lighting device using the present invention will be described as an example. In this case, the material illuminated by the illumination in the venue where the presentation is performed is imaged, and the RGB balance of the light emitted from the illumination unit is adjusted using the captured image.

  In this way, the illumination from the illumination means is matched to the RGB balance of the venue illumination. In this case, since the RGB balance of the lighting in the venue and the RGB balance from the lighting device provided in the material presentation device match (or substantially match), the uneven white balance caused by the mismatch of the RGB balance of the illumination light is suppressed. Can do.

  The lighting device of the present invention is preferably applied to a material presentation device. However, the present invention is not necessarily limited thereto, and the present invention can be widely applied to lighting devices used when imaging an object to be imaged.

  The operation of the lighting device of the present invention can be grasped as an invention of a lighting method. That is, in the illumination method of the present invention, the RGB balance detection step of detecting the RGB balance of the reflected light from the imaging target in a state where the illumination unit is turned off when imaging the imaging target illuminated by the illumination unit. A luminance distribution state detecting step for detecting unevenness of the luminance distribution due to illumination of the imaging target from the captured image of the imaging target; and the detected RGB balance for the imaging target and the unevenness of the luminance distribution. It can be grasped as a procedure including an irradiation step of correction illumination light that irradiates correction illumination light having a light emission amount distribution to be canceled.

  According to the present invention, in the illumination for irradiating the imaging target, adjustment is made so that RGB balance unevenness does not occur on the irradiated surface, and the emission amount distribution is intentionally adjusted so that luminance unevenness does not occur in the captured image. . As a result, the RGB balance unevenness and the brightness unevenness of the light hitting the imaging target can be suppressed. By utilizing this principle, it is possible to effectively improve white balance unevenness and luminance unevenness in a captured image when capturing a material in the material presenting apparatus.

1. Configuration of Embodiment Hereinafter, an example in which the illumination device and the illumination method of the present invention are applied to a material presentation device will be described. FIG. 1 is an image diagram showing an outline of a presentation system using a material presentation device equipped with a lighting device using the present invention.

  This presentation system includes a material presentation device 101, an image projection device 122, and a projection screen 123.

  The material presentation device 101 includes an imaging device 102, an arm 103, a material placement table 104, operation buttons 105, a display 107, and a lighting device 108.

  The imaging device 102 includes an imaging unit 102 a such as a CCD camera and an image processing unit 102 b that detects and adjusts the white balance of the captured image, and has a function of imaging the material 106 placed on the material mounting table 104. . The arm 103 is a support that supports the imaging device 102. The operation button 105 is an operation unit for performing a power switch of the material presentation device 101 and various operations. The display 107 displays the operation content and operation menu of the material presentation device 101. In addition, the display 107 can display an image captured by the imaging device 102.

  The illumination device 108 has a function of auxiliary illumination that illuminates the material 106 placed on the material placement table 104. The lighting device 108 has a structure in which the matrix LED array 110 is supported by an arm 109. The matrix LED array 110 has a structure in which RGB light sources 111 in which RGB LED light sources are integrated are arranged in a matrix of, for example, 7 rows × 14 columns. The matrix LED array 110 is attached to the arm 109 so that the direction of irradiation light can be freely set.

  FIG. 2 is a front view showing an example of the structure of the matrix LED array 110. In the matrix LED array 110, RGB light sources 111 are arranged in an array of 7 columns × 14 rows, for example. The RGB light source 111 has a structure in which an LED 201 that emits red (R) wavelength, an LED 202 that emits green (G) wavelength, and an LED 203 that emits blue (B) wavelength are combined into one package. . The light emission intensity of each of the RGB light sources can be adjusted independently. By making this adjustment, the RGB balance of the light emitted by the RGB light source 111 can be adjusted. Further, by adjusting the light emission intensity of each of the RGB light sources while maintaining the RGB balance, the light emission amount of illumination emitted from the matrix LED array 110 can be adjusted. Further, the adjustment of the light emission amount can be performed partially on the light emitting surface of the matrix LED array 110. Thereby, the distribution of the surface emitting state of the matrix LED array 110 can be adjusted.

  The image projection device 122 shown in FIG. 1 has a function of projecting and displaying an image sent from the material presentation device 101 via the image transmission cable 121 on the projection screen 123. That is, the material 106 placed on the material mounting table 104 is imaged by the imaging device 102, the captured image is sent to the image projection device 122, and the image projection device 122 projects the image on the projection screen 123. Thus, a not-shown presenter (presenter) can make a presentation while presenting the document as an image to the viewer.

  FIG. 1 also shows a lighting fixture 124 that illuminates the venue where the presentation is to be held. Here, an example in which the brightness in the hall is adjusted by the lighting fixture 124 is shown, but a form in which the brightness in the hall is adjusted by incorporating external light into the hall may be used. In addition to illumination by the lighting fixture 124, light entering from outside the venue may affect the brightness in the venue.

  FIG. 3 is a block diagram of the material presentation device 101. As shown in FIG. 3, in the material presentation device 101, image data captured by the imaging device 102 is sent to the illumination light characteristic analysis unit 301 and the data capturing unit 303. The illumination light characteristic analysis unit 301 analyzes luminance and hue in an image captured by the imaging device 102. Based on the result of this analysis, the illumination control unit 302 controls the matrix LED array 110 of the illumination device 108 to suppress uneven luminance and uneven hue in the captured image. Details of operations of the illumination light characteristic analysis unit 301 and the illumination control unit 302 will be described later.

  On the other hand, the data capture unit 303 that captures the captured image sends image data to the image data output unit 304. The data capturing unit 303 has a function of storing image data in a data storage unit (for example, a semiconductor memory or a hard disk device) 305 and a function of reading out image data from the data storage unit 305. The image data sent to the image data output unit 304 is sent to the projection device 122 (see FIG. 1).

  The control button 105 shown in FIG. 1 is used to control the imaging timing of the imaging device 102, control the transmission timing of image data to the projection device 122, and to instruct white balance adjustment processing and luminance distribution adjustment processing described later. It is done by being manipulated.

2. Operation of Embodiment FIG. 4 is a flowchart showing a processing procedure for suppressing luminance unevenness and color unevenness and a procedure for presenting materials.

  Here, an example will be described in which the presenter places a material 106 on the material placing table 104 of the material presenting apparatus 101 and projects the placed material 106 on a screen 123 for presentation.

  First, a calibration reference sheet (for example, white paper) for adjusting white balance and brightness is placed on the material placing table 104 (step S401). Then, in a state in which the illumination device 108 is turned off, the calibration reference sheet placed on the material placement table 104 is imaged using the imaging unit 102a (step S402). This captured image is sent to the image processing unit 102b, and the state of white balance is detected (step S403).

  Then, the RGB components are adjusted (white balance adjustment) so that “white” is substantially reproduced in the image processing unit 102b (step S404), and then the white balance adjustment result obtained in step S404 is illuminated. The light characteristic analysis unit 301 performs analysis. In this analysis, RGB balance values that do not impair the white balance obtained by the light emitted from the lighting fixture 124 are calculated based on the white balance adjustment result obtained in step S404. That is, an analysis is performed to match the RGB balance of the light emitted from the lighting device 108 with the RGB balance of the light emitted from the lighting fixture 124. And the illumination control part 302 controls the illuminating device 108 based on this analysis result.

  That is, the white balance adjustment result obtained in step S404 is analyzed, and based on the analysis result, the RGB intensity of the irradiation light from the illumination device 108 is controlled (step S405). As a result, light having the same RGB balance as that of the lighting fixture 124 in the hall is emitted from the lighting device 108.

  Next, the illumination device 108 is turned on, and RGB balance illumination by the control in step S405 is applied to the calibration reference sheet on the document mounting table 104 (step S406), and the illuminated calibration reference sheet is imaged. An image is captured by the camera 102 (step S407). The captured image obtained by this imaging is sent to the illumination light characteristic analysis unit 301, and uneven brightness in the captured image is detected (step S408). Then, the illumination control unit 302 adjusts the light emission distribution of the matrix LED array 110 so that the illumination is performed with the light emission amount distribution that reduces the luminance unevenness (step S409). That is, the light emission intensity distribution of the matrix LED array 110 is adjusted so as to irradiate illumination light having a light emission amount distribution that cancels unevenness of the luminance distribution in the material mounting table 104.

  In this way, adjustment is performed so that luminance unevenness and color unevenness do not occur in the illuminated state. Once you get this status, you can give an actual presentation.

  When giving a presentation, first, a material to be presented (displayed on the screen 123) is placed on the material mounting table 104 (step S410). Then, the operation button 105 is operated to image the material placed on the material placement table 104 (step S411). An image obtained as a result of imaging is sent to the image projection device 122 via the data capturing unit 303 and the image data output unit 304, and the image projection device 122 projects the image onto the projection screen 123. Then, a presentation is performed using the projected image.

  If it is detected that a new material has been placed, the determination in step S412 is YES, and the processing from step S411 onward is executed again. When a new material is not placed, the process proceeds from step S412 to step S413.

  If the document presentation action is to be ended, the operation button 105 for issuing an instruction to that effect is pressed, the determination in step S413 is YES, and the process ends. If the document presentation action does not end, the process returns from step S413 to step S412 to repeat the determination in step S412.

  In this way, in the projection of the material 106 onto the screen 123, it is possible to suppress unevenness in color and brightness in the projected image. In particular, in the processing in step S405, since the RGB balance of the lighting device 108 is adjusted to match the RGB balance of the lighting in the hall, the projection screen 123 does not matter what the RGB balance of the lighting in the presentation hall is. The white balance of the image projected on the screen is not uneven.

  Further, by adjusting the surface light emission distribution of the matrix LED array 110, the uneven brightness on the surface of the material 106 can be corrected. That is, the luminance in the captured image of the document 106 is adjusted by canceling the unevenness of light (partial strength non-uniformity) that hits the material 106 and adjusting the surface light emission distribution of the matrix LED array 110 so that the uniform light hits as a result. It is possible to prevent unevenness from occurring.

  In particular, in this processing, the influence of lighting of the lighting fixture 124 in the presentation hall is taken into consideration. For this reason, it is possible to effectively suppress uneven white balance and uneven brightness due to the influence of the lighting fixture 124.

3. Color adjustment (Adjustment of RGB balance of lighting device 108)
Hereinafter, adjustment of RGB balance will be described. Here, an example in which white paper is used as the calibration reference paper will be described. Hereinafter, a specific example of the process performed in step S405 of FIG. 4 will be described. FIG. 5 is a flowchart showing a procedure of a specific example of processing for adjusting RGB balance.

  First, in a state where the illumination by the illumination device 108 is turned off, the calibration reference sheet (white paper) placed on the material placement table 104 is imaged (step S501). Next, the illumination light characteristic analysis unit 301 acquires RGB values from the captured image (step S502). That is, the levels of the R component, G component, and B component in an appropriate portion (for example, the central portion) of the captured image of the calibration reference sheet are acquired.

  Then, the illumination light characteristic analysis unit 301 determines whether the R value is within a predetermined range (step S503). If the R value is not within the predetermined range, the process proceeds to step S504, where the R value falls within the predetermined range. If it is within the range, the process proceeds to step S506.

  Here, the predetermined range related to the R value is a level range indicated by the R component in a state where a standard RGB balance is obtained. The predetermined range related to the R value is obtained experimentally in advance and stored in a memory (not shown) in the illumination light characteristic analysis unit 301. A predetermined range related to the G value described later is a level range indicated by the G component in a state where the standard RGB balance is obtained, and a predetermined range related to the B value described later is obtained as a standard RGB balance. The level range indicated by the B component in the

  In step 504, a difference from a predetermined range of the R value (a predetermined range related to the R value determined in step S503) is calculated. Then, the light emission intensity of the LED for R component light emission (reference numeral 201 in FIG. 3) corresponding to the difference is set (step S505). The process in step S504 is performed in the illumination light characteristic analysis unit 301, and the process in step S505 is performed in the illumination control unit 302.

  For example, when the R component acquired in step S502 is smaller than the value of the R component when a predetermined RGB balance is obtained, the missing amount is calculated in step S504, and the emission intensity at a level obtained by subtracting the missing amount Is set in step S505.

  If the determination in step S503 is YES, or if the process in step S505 is performed, the process proceeds to step S506, where it is determined whether the G value is within a predetermined range. If the G value is not within the predetermined range, step S506 is performed. The process proceeds to S507, and if the G value is within the predetermined range, the process proceeds to Step S509.

  In step 507, a difference from a predetermined range of the G value (a predetermined range relating to the G value determined in step S506) is calculated. Then, the light emission intensity of the LED for G component light emission (reference numeral 202 in FIG. 3) corresponding to the difference is set (step S508).

  If the determination in step S506 is YES, or if the process in step S508 is performed, the process proceeds to step S509, where it is determined whether the B value is within a predetermined range. If the B value is not within the predetermined range, step S509 is performed. Proceeding to S510, if the B value is within the predetermined range, the process is terminated.

  In step 510, a difference from a predetermined range of the B value (a predetermined range related to the B value determined in step S509) is calculated. Then, the light emission intensity of the LED for B component light emission (reference numeral 203 in FIG. 3) corresponding to the difference is set (step S511).

  In this way, the RGB balance of the illumination light of the illumination device 108 is adjusted so that the white balance of the captured image when the illumination device 108 is not activated is also reproduced when the illumination device 108 is activated. Thereby, it is possible to prevent uneven white balance in the captured image due to the difference in RGB balance between the illumination from the indoor lighting fixture 124 and the illumination from the illumination device 108.

  Since this method is adjusted in accordance with the RGB balance of the luminaire 124, there is an advantage that optimum adjustment can be performed for each venue where the presentation is performed.

4). Adjustment of luminance unevenness Hereinafter, adjustment of luminance unevenness will be described in detail. Here, an example in which white paper is used as the calibration reference paper will be described. In this case, the field of view of the captured image is divided into m × n (for example, 7 × 14) detection pixels, and the brightness obtained from the center portion of each detection pixel is detected. This brightness is converted into a numerical value (luminance detection value), and the numerical value is used as a comparison target. If there is no unevenness in luminance, the m × n luminance detection values are the same or fall within a predetermined range.

  If there are variations in the m × n luminance detection values, all the luminance detection values match a predetermined numerical value corresponding to an appropriate luminance value (or fall within a predetermined range). ) The emission intensity of each RGB light source constituting the matrix LED array 110 is adjusted.

  Hereinafter, a specific example of the processing in steps S406 to S409 will be described. FIG. 6 is a flowchart showing the procedure of a specific example of the process for adjusting the luminance distribution. First, in a state where the illumination by the illumination device 108 is turned on, the calibration reference paper (white paper) placed on the material placement table 104 is imaged (step S601). Next, a detection pixel is selected from the captured image (step S602). For example, if m × n detection pixels are set, a pixel with m = 1 and n = 1 is selected first (usually, the detection pixel located at the uppermost left end).

  Next, the luminance at the selected detection pixel is acquired (step S603). The luminance is obtained by detecting each value of RGB and adding the three values. For example, the luminance is acquired at the center of the detection pixel.

  Next, the illumination light characteristic analysis unit 301 determines whether or not the acquired luminance is within a predetermined range (step S604). If the luminance value is within the predetermined range, the process proceeds to step S608. If the luminance value is not within the predetermined range, the process proceeds to step S605.

  Here, the predetermined range is a preferable range of luminance to be aimed at. The predetermined range is experimentally obtained in advance and stored in a memory (not shown) in the illumination light characteristic analysis unit 301.

  When the process proceeds to step S605, the illumination light characteristic analysis unit 301 determines whether the luminance value is less than or exceeds the predetermined range used in the determination of step S604. If the luminance value exceeds the predetermined range, the illumination control unit 302 performs a setting process (step S606) to decrease the emission intensity of the corresponding RGB light source by a predetermined amount. Conversely, if the luminance value is less than the predetermined range. For example, the illumination control unit 302 performs setting processing (step S607) for increasing the emission intensity of the corresponding RGB light source by a predetermined amount.

  Here, the corresponding RGB light source refers to an RGB light source (reference numeral 111 in FIG. 3) that mainly affects the luminance of the detection pixel selected in step S602. Here, the number of corresponding RGB light sources may be one or plural. The relationship between the detection pixel and the corresponding RGB light source is experimentally obtained in advance, and a data table indicating the correspondence relationship is stored in a memory (not shown) in the illumination control unit 302.

  If the process of step S606 or S607 is performed, the process returns to the previous stage of step S601, and the processes after step S601 are executed again. If the luminance value acquired in this re-processing is not within the predetermined range, the processing in S606 or S607 is executed again. In this way, adjustment is performed to increase or decrease the emission intensity of the corresponding RGB light source so that the luminance level of the detection pixel in the captured image is within a predetermined range.

  If the determination in step S604 is YES, it is determined whether there is an unprocessed detection pixel (step S608). If there is an unprocessed detection pixel, the next pixel is selected (step S609). In this case, the adjustment process of the intensity of the illumination light with respect to the next detection pixel is performed by executing the process after step S602 again.

  If there is no unprocessed detection pixel, the process is terminated. In this way, the emission intensity is adjusted for each RGB light source of the matrix LED array 110 corresponding to each detection pixel so that the luminance of all the detection pixels falls within a predetermined range. According to this processing, the light emission intensity distribution of the matrix LED array 110 is adjusted so as to irradiate illumination light having a light emission amount distribution that cancels unevenness of the luminance distribution in the material mounting table 104. That is, the light emission intensity distribution in the matrix LED array 110 is adjusted so that luminance unevenness does not occur in the captured image.

5). Advantages of the Embodiments As described above, unevenness in the color of light hitting the document mounting table 104 and unevenness in the luminance distribution are detected in advance, and the light emission amount distribution of the illumination from the illumination device 108 and the RGB balance are detected based on the detection result. Adjust. Thereby, it is possible to suppress the occurrence of uneven coloring or uneven brightness in the captured image due to the influence of the light from the lighting device 108 and the light from the lighting fixture 124.

  In addition, the above-described color adjustment and light emission amount adjustment are performed by adjusting the degree of illumination from the illumination device 108. Therefore, when adjusting a partial color difference or brightness difference by image processing. In comparison, a more reliable effect can be obtained with simpler control.

6). Modification of Embodiment The material presentation device 101 illustrated in FIG. 1 may include a plurality of lighting devices 108. Further, the shape of the matrix LED array 110 of the illumination device 108 is not limited to a quadrangular shape. In addition, a structure integrated with the imaging device 102 or the like can be employed as the lighting device.

  The present invention can be used for a material presentation device that presents materials as images in lectures, seminars, and various classes. Further, the present invention can be applied to an illumination device used when imaging an imaging target.

It is an image figure which shows the outline | summary of the presentation system using the material presentation apparatus using invention. It is a front view which shows an example of the structure of a matrix LED array. It is a block diagram for demonstrating the function of a material presentation apparatus. It is a flowchart which shows the procedure at the time of performing the procedure of a process for suppressing the brightness nonuniformity and the nonuniformity of a hue, and a document. It is a flowchart which shows the example of the specific procedure of the process for adjusting RGB balance. It is a flowchart which shows the example of the specific procedure of the process for adjusting light emission amount distribution.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 101 ... Material presentation apparatus, 102 ... Imaging device, 102a ... Imaging part, 102b ... Image processing part, 103 ... Arm, 104 ... Material mounting base, 105 ... Control button, 106 ... Material, 107 ... Display, 108 ... Illumination device, DESCRIPTION OF SYMBOLS 109 ... Arm, 110 ... Matrix LED array, 111 ... RGB light source, 121 ... Image transmission cable, 122 ... Projection apparatus, 123 ... Projection screen, 124 ... Lighting equipment, 201 ... LED which emits the wavelength of red (R), 202 ... LEDs that emit green (G) wavelengths, 203 ... LEDs that emit blue (B) wavelengths.

Claims (3)

Illuminating means for illuminating the imaging target with illumination light;
Illumination control means for controlling the illumination means;
Illumination light characteristic analysis means for detecting RGB balance and luminance distribution in the captured image of the imaging target,
The illumination control means includes
Adjust the RGB balance of the illumination for the imaging object,
Furthermore, the illuminating device characterized by partially adjusting the light emission amount of the illumination with respect to the imaging target. The illumination means is an array light source in which three RGB light sources are arranged in a matrix,
The RGB balance is adjusted by individually adjusting the light emission amounts of the three RGB light sources,
The lighting device according to claim 1, wherein the light emission amount is partially adjusted by adjusting a light emission distribution in the array light source. When imaging the imaging target illuminated by the illumination means,
An RGB balance detection step for detecting the RGB balance of the reflected light from the imaging target in a state where the illumination means is turned off;
A luminance distribution state detection step for detecting unevenness of luminance distribution due to illumination of the imaging target from a captured image of the imaging target;
An illumination method comprising: irradiating corrected illumination light that irradiates the imaging target with corrected illumination light having the detected RGB balance and having a light emission amount distribution that cancels the unevenness of the luminance distribution. .

Images