JP2005214806A - Light measurement instrument, lighting system, and evaluation system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily measure a light distribution in an actual environment. <P>SOLUTION: This light measuring instrument 1 converges light in a space by an optical system 11, respective photoelectric transfer elements detect the light converged by the optical system 11 to be converted into a detection data by a photoelectric transfer part 21 arranged with the plurality of photoelectric transfer elements. A calculation part 41 calculates a measured light quantity on the basis of the detection data to obtain the light distribution in the space. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a light measurement device, a lighting device, and an evaluation system, and in particular, a light measurement device that measures light distribution in an environment for evaluating a display device, a lighting device that reproduces light distribution in an environment for evaluating a display device, The present invention also relates to an evaluation system for evaluating a display device.

  Display devices are used in various electronic devices such as personal computers, mobile phones, and digital still cameras, and are used in various environments, both indoors and outdoors. For example, indoors, in general environments where lighting devices are installed on the ceiling, such as offices and classrooms, and in special environments where indirect light and spot light sources are installed, such as hotel lobbies, A display device is used. In addition, outside the room, the display device is used in an environment that is sufficiently bright without being blocked by sunlight, or in an environment where the sunlight is blocked and darkened by a building or the like. As described above, the display device is used in various light environments, and image characteristics may be deteriorated due to, for example, flare such as surface reflection.

  In particular, a display device mounted on a portable terminal such as a mobile phone often uses a reflective liquid crystal display device or a combined liquid crystal display device that uses both a reflective type and a transmissive type. Since light is used, the light environment at the time of use has a great influence on the image characteristics.

For this reason, display devices such as reflective and combined liquid crystal display devices have been evaluated for image characteristics using various light sources such as a point light source, a total diffuse light source, a partial diffuse light source, and a ring light source (for example, Non-patent document 1).
Japan Electromechanical Industry Standard ED2523 Reflective LCD module measurement method)

  However, the light environment in which the display device is actually used differs from the case of using a light source such as a point light source, a fully diffusing light source, a partially diffusing light source, or a ring light source. Is affected. For this reason, the evaluation result in the light environment by the point light source, the total diffusion light source, the partial diffusion light source, the ring light source, etc. may be different from the evaluation result in the actually used light environment. It was difficult to grasp the characteristics.

  Therefore, we measured the light distribution in the real environment using an integral illuminometer and tried to reproduce the light environment where the display device was actually used. However, the integral illuminometer entered the light receiving part. In order to measure the amount of energy obtained by integrating all of the light to be transmitted, it is difficult to accurately measure the light incident from various directions, and it is difficult to measure the light distribution.

  Thus, conventionally, since the light distribution in the real environment cannot be easily measured, the light distribution in the real environment cannot be reproduced, and it becomes difficult to grasp the image characteristics of the display device in the real environment. It was. For this reason, it is not easy to improve the image characteristics of the display device.

  Therefore, the present invention provides a light measurement device, a lighting device, and an evaluation system that can easily measure and reproduce a light distribution in a real environment and easily evaluate image characteristics and the like of a display device. For the purpose.

  In order to achieve the above object, a light measurement device according to the present invention is a light measurement device for measuring a light distribution in a space, and includes an optical system for condensing the light in the space, and light collected by the optical system. Photoelectric conversion means in which a plurality of photoelectric conversion elements that detect and convert to detection data are arranged, and calculation means for calculating a photometric quantity based on detection data from the photoelectric conversion elements and obtaining a light distribution in the space.

  As described above, the light measurement device of the present invention collects light in the space by the optical system. Each photoelectric conversion element detects and converts the light collected by the optical system into detection data by a photoelectric conversion means in which a plurality of photoelectric conversion elements are arranged. Then, the photometric quantity is calculated by the calculation means based on the detection data obtained by the photoelectric conversion element to obtain a spatial light distribution.

  In order to achieve the above object, an illuminating device of the present invention is an illuminating device that illuminates an object so as to simulate a spatial light distribution, and inputs measurement data of the spatial light distribution. Means, illumination means for illuminating the object, and control means for controlling the illumination means based on the measurement data input from the input means, wherein the measurement data is collected by an optical system. The data relating to the light distribution generated by the detection data obtained by the photoelectric conversion element.

  As described above, the illuminating device of the present invention inputs measurement data related to the light distribution in the space, which is collected by the detection data obtained by the photoelectric conversion element and collected by the optical system, by the input unit. Based on the measurement data input from the input means, the control means controls the illumination means to illuminate the object.

  In order to achieve the above object, an evaluation system of the present invention is an evaluation system for evaluating an image displayed on a display device, and the illumination device illuminates the display device, and is illuminated by the illumination device. An image measuring device for measuring image characteristics of the display device, wherein the lighting device is input means for inputting measurement data of light distribution in the space, lighting means for illuminating the object, and the input means. Control means for controlling the illuminating means based on the measurement data input from the light, and the measurement data is collected by an optical system and generated by detection data obtained by a photoelectric conversion element. It is data about distribution.

  As described above, in the evaluation system of the present invention, the measurement data related to the light distribution in the space, which is collected by the detection data obtained by the photoelectric conversion element and collected by the optical system, is input by the input unit of the illumination device. Then, based on the measurement data input from the input unit, the control unit of the illumination device controls the illumination unit to illuminate the object. Then, the image characteristic of the display device illuminated by the illumination device is measured by the image measurement device.

  According to the present invention, it is possible to easily measure and reproduce the light distribution in the real environment, and to easily evaluate the image characteristics and the like of the display device.

  An example of an embodiment according to the present invention will be described below.

  FIG. 1 is a configuration diagram illustrating a main part of the light measurement device 1 of the present embodiment.

  As shown in FIG. 1, the optical measurement device 1 of the present embodiment includes an optical system 11, a photoelectric conversion unit 21, an exposure amount control unit 31, a calculation unit 41, a correction unit 42, a storage unit 51, A display unit 61 and an operation unit 71 are provided. Note that the optical system 11 of the present embodiment corresponds to the optical system of the present invention. Further, the photoelectric conversion unit 21 of the present embodiment corresponds to the photoelectric conversion means of the present invention. The exposure amount control unit 31 of this embodiment corresponds to the exposure amount control means of the present invention. Moreover, the calculation part 41 of this embodiment is corresponded to the calculation means of this invention. Further, the correction unit 42 of the present embodiment corresponds to a correction unit of the present invention. The storage unit 51 of the present embodiment corresponds to the storage unit of the present invention. The display unit 61 of this embodiment corresponds to the display unit of the present invention.

  The optical system 11 is provided to collect light in space. The optical system 11 includes a wide-angle lens having a wide viewing angle of 80 ° or more in order to obtain a light distribution in a wide space. In the present embodiment, a fish-eye lens (manufactured by Nikon Corporation, trade name: Nikon Fisheye NIKOR 8 mm F2.8) having a viewing angle of approximately 180 ° is used as the wide-angle lens.

  The photoelectric conversion unit 21 includes a plurality of photoelectric conversion elements that detect the light collected by the optical system 11 and convert it into detection data. Each photoelectric conversion element is two-dimensionally arranged in a matrix. In the present embodiment, a CMOS digital still camera (manufactured by Kodak Company, trade name: DCS Pro14n) is used as the photoelectric conversion unit 21. The detection data obtained by the photoelectric conversion unit 21 is decomposed and detected for each of the three RGB colors, and is output to the calculation unit 41.

The exposure amount control unit 31 is configured by a computer, and controls the amount of light collected by the optical system 11 that is exposed to the photoelectric change element of the photoelectric conversion unit 21. The exposure amount control unit 31 is connected to a digital still camera including the photoelectric conversion unit 21 and controls the exposure amount to the photoelectric conversion element by controlling at least one of the aperture 32 and the exposure time. In the present embodiment, the exposure amount control unit 31 controls the exposure amount so as to satisfy a plurality of conditions. For example, the exposure amount control unit 31 fixes the diaphragm 32 to F5.6 according to a command from the operation unit 71, and sets the exposure time to three exposure conditions of 1/2 second, 1/60 second, and 1/2000 second. Control to be. Although details will be described later, by controlling in this way, for example, it is possible to measure a luminance of 1 to 23000 cd / m ² .

  The calculation unit 41 is configured by, for example, a computer, calculates a photometric amount based on detection data by a photoelectric conversion element of the photoelectric conversion unit 21, and generates a spatial light distribution. In the present embodiment, the calculation unit 41 calculates the luminance as the photometric quantity and obtains the luminance map information as the spatial light distribution. Further, the calculation unit 41 divides the photoelectric conversion elements in the photoelectric conversion unit 21 into a plurality of groups, and calculates the luminance that is a photometric value for each group based on the detection data corresponding to each group. In addition, the calculation unit 41 obtains a spatial light distribution based on the detection data acquired for the exposure amounts under the three plural conditions as described above. Specifically, the calculation unit 41 calculates a relational expression between luminance and gradation in advance based on detection data by the photoelectric conversion element so as to correspond to the exposure amount controlled by the exposure amount control unit 31. The data is stored in the storage unit 51. Then, the calculation unit 41 calculates the gradation of each photoelectric conversion element based on the detection data in the measurement environment under a plurality of exposure amount conditions, and the relational expression stored in the storage unit 51 and the calculated floor. Based on the tone, the luminance corresponding to each photoelectric conversion element is calculated. Then, for example, a 256 × 256 luminance map is generated by mapping the luminance corresponding to each photoelectric conversion element. Furthermore, the calculation unit 41 calculates, for example, an average value of luminances grouped in a region having an azimuth angle of 15 ° and an incident angle of 15 °, and indicates the average luminance of each group. Generate map information. Thus, the calculation unit 41 generates a plurality of pieces of luminance map information.

  The correcting unit 42 corrects the light distribution calculated by the calculating unit 41 based on a photometric value correction coefficient corresponding to the incident angle of light to the optical system 11. The correction unit 42 performs correction by applying the correction coefficient stored corresponding to each incident angle to the photometric value at each incident angle.

  The storage unit 51 is configured by a memory, for example, and stores a relational expression between luminance and gradation so as to correspond to the exposure amount controlled by the exposure amount control unit 31. The storage unit 51 also stores a photometric value correction coefficient corresponding to the incident angle of the light to the optical system 11.

  The display unit 61 is configured by a liquid crystal display device, for example, and displays the light distribution of the space generated by the calculation unit 41. Then, the display unit 61 switches and displays a plurality of pieces of luminance map information in accordance with a command from the operation unit 71. Further, the display unit 61 displays the value of the luminance at the location selected in the displayed luminance map information in accordance with a command from the operation unit 71.

  The operation unit 71 is configured by an input device such as a keyboard and a mouse, for example, and operation information is input by an operator, and an operation signal is output to each unit based on the input operation information. For example, the operation unit 71 receives an exposure condition as a measurement condition, and outputs an operation signal corresponding to the exposure condition to the exposure amount control unit 31. For example, the operation unit 71 receives operation information for switching luminance map information to be displayed on the display unit 61 and outputs an operation signal corresponding to the operation information to the display unit 61.

  Note that the optical system 11 of the light measurement apparatus 1 of the present embodiment corresponds to the optical system of the light measurement apparatus of the present invention. And the photoelectric conversion part 21 of the optical measurement apparatus 1 of this embodiment is corresponded to the photoelectric conversion means of the optical measurement apparatus of this invention. Further, the exposure amount control unit 31 of the light measurement device 1 of the present embodiment corresponds to the exposure amount control means of the light measurement device of the present invention. And the calculation part 41 of the optical measurement apparatus 1 of this embodiment is corresponded to the calculation means of the optical measurement apparatus of this invention. Moreover, the correction | amendment part 42 of the optical measurement apparatus 1 of this embodiment is corresponded to the correction | amendment means of the optical measurement apparatus of this invention. And the memory | storage part 51 of the optical measurement apparatus 1 of this embodiment is corresponded to the memory | storage means of the optical measurement apparatus of this invention. Further, the display unit 61 of the light measurement device 1 of the present embodiment corresponds to the display unit of the light measurement device of the present invention.

  Hereinafter, a measurement method using the light measurement apparatus 1 will be described.

  FIG. 2 is a flowchart of a measurement method for obtaining luminance map information using the light measurement apparatus 1 described above.

  First, prior to performing the measurement as shown in FIG. 2, a spatial image with a plurality of luminance conditions is set by combining a diffused light source having a uniform luminance distribution and an ND filter, and exposure is performed by the light measurement apparatus 1 described above. A spatial image of each luminance condition is taken by sequentially changing the amount, and a relational expression between luminance and gradation is calculated. Then, the calculated relational expression between brightness and gradation is stored in the storage unit 51.

  FIG. 3 is a diagram showing luminance and gradation in correspondence with exposure amounts. In FIG. 3, the horizontal axis indicates luminance with a logarithmic value, and the vertical axis indicates gradation with a logarithmic value. In this embodiment, the diaphragm 32 is fixed to F5.6, and the exposure time is 1/2 second, 1/4 second, 1/8 second, 1/15 second, 1/30 second, 1/60 second. , 1/125 seconds, 1/250 seconds, 1/500 seconds, 1/1000 seconds, 1/2000 seconds, and so on, so that the exposure amount is controlled.

As shown in FIG. 3, by controlling the exposure amount as the exposure time of 1/2 second, 1/60 second, and 1/2000 ^second , luminance in the range of 1 to 23000 cd / m ² can be obtained. For this reason, based on the result of FIG. 3, the relational expression of the brightness | luminance in 1/2 second, 1/60 second, and 1/2000 second is represented by Formula (1), Formula (2), Formula (3). Calculate as follows.

L _1/2 = 10 ^{(log G-log 35.113) / (0.5381)} (1)

L _1/60 = 10 ^{(log G-log 3.1118) / (0.6137)} (2)

L _1/2000 = 10 ^{(log G-log 0.2649) / (0.6674)} (3)

In the above formulas (1), (2), and (3), L _1/2 represents the luminance at an exposure time of 1/2 second, and L _1/60 represents the exposure time at 1/60 second. The luminance indicates luminance, L _1/2 indicates luminance at an exposure time of 1/2 second, and G indicates gradation.

  Further, it is known that the amount of light collected by the wide-angle lens constituting the optical system 11 of the light measuring device 1 decreases as the distance from the center increases. Therefore, the luminance with respect to the incident angle of the light to the wide-angle lens of the optical system 11 is measured, and the luminance correction coefficient is calculated. In the present embodiment, luminance measurement is performed by shifting the light source position by 5 ° from 0 ° to 85 °, which is the center of the lens.

  FIG. 4 is a diagram illustrating a result of luminance with respect to an incident angle of light to the wide-angle lens of the optical system 11. In FIG. 4, the horizontal axis represents the incident angle of light to the wide-angle lens, and the vertical axis represents the relative value of luminance when the luminance at the lens center is 100. As shown in FIG. 4, the luminance decreases as the light source shifts from the lens center to the periphery. Then, the result shown in FIG. 4 is approximated to a cubic polynomial, and a relational expression between the correction coefficient y and the incident angle x is derived as in Expression (4). Then, the luminance correction coefficient corresponding to the incident angle of the light to the optical system 11 is stored in the storage unit 51.

y = −0.0001 · x ³ + 0.006 · x ² + 0.1686 · x + 100.53 (4)

  In this way, the relational expression between the brightness and the gradation is stored in the storage unit 51 in association with the exposure amount, and the brightness correction coefficient corresponding to the incident angle of the light to the optical system 11 is stored in the storage unit 51. .

  Then, as shown in FIG. 2, the light distribution in a desired space is measured. First, the light measurement device 1 is installed in a space for measuring light distribution, and measurement conditions are set (ST11). For example, as an exposure amount condition, the diaphragm 32 is fixed to F5.6, and a command is given to the exposure amount control unit 31 so that three exposure times of 1/2 second, 1/60 second, and 1/2000 second are obtained. input. Other measurement conditions are 1125 × 750 pixels, ISO sensitivity 100, white balance 5000K, digital exposure correction off, storage format JPEG FILE TYPE ERI, and aspect ratio 2: 3.

  Next, aerial image detection data is acquired based on the set measurement conditions (ST21). Specifically, a measurement start command is input, and the exposure amount controller 31 controls the aperture 32 and the shutter speed based on the three exposure amount conditions, and the aerial image under each exposure condition is transmitted via the optical system 11. Then, the photoelectric conversion unit 21 picks up an image to obtain detection data under each exposure condition. Here, the detection data is decomposed and detected for each of the three RGB colors.

  Next, a photometric value is calculated based on the detection data (ST31). First, the detection data is read into the calculation unit 41, and the calculation unit 41 cuts out the detection data corresponding to the measurement area and reduces the data size to 256 × 256 pixels. Here, in the present embodiment, since the light is condensed by the wide-angle lens and captured by the photoelectric conversion unit 21, a spatial image of the measurement target is captured as a circular two-dimensional image. As a reduction method, the nearest neighbor method is used. Thereafter, the calculation unit 41 converts the detection data into a gray scale by taking the average value of the gradations of the three RGB colors in the detection data.

  And the calculation part 41 calculates the brightness | luminance of each pixel of the aerial image in each exposure amount based on the above-mentioned Numerical formula (1), Numerical formula (2), Numerical formula (3). After the luminance calculation, the correction unit 42 corrects the luminance corresponding to the incident angle of the light to the optical system 11 based on the above-described equation (4). Here, correction is performed using each pixel value in the gradation range of 25 to 220 in order to remove noise. In this way, the calculation unit 41 calculates the luminance as the photometric amount.

  Next, by mapping the calculated luminance, luminance map information is generated as a spatial light distribution (ST41). Each calculated luminance value is mapped so as to have a size of 256 × 256, thereby generating luminance map information.

  In addition, the photoelectric conversion elements in the photoelectric conversion unit 21 are divided into groups, and based on the detection data corresponding to the groups, the average luminance that is a photometric value of each group is calculated, and the average luminance is mapped. Thus, luminance map information in units of groups is generated.

  FIG. 5 is a diagram illustrating a state in which the photoelectric conversion elements are divided into groups in the photoelectric conversion unit 21. In the present embodiment, as described above, light is collected by the wide-angle lens and a circular image is picked up by the photoelectric conversion unit 21, and thus the photoelectric conversion elements corresponding to the circular image are divided into groups. For example, the calculation unit 41 divides a region corresponding to the circular image into 144 regions so that the azimuth angle is 15 ° and the incident angle is 15 °, and groups the photoelectric conversion elements in the respective divided regions. . Then, the calculation unit 41 calculates an average value of the pixel values in the group, and calculates the average luminance of each group at each exposure amount based on the above formula (1), formula (2), and formula (3). To do. In this way, the calculation unit 41 calculates the average luminance of each group, and maps the calculated average luminance to generate 144 area luminance map information as a spatial light distribution.

  Next, the display unit 61 displays the luminance map information generated by the calculation unit 41 (ST51). Further, when a desired location is selected in the displayed luminance map information by an operation from the operation unit 71, the display unit 61 displays the brightness value of the selected location. As described above, the spatial light distribution is measured, and the spatial light distribution can be known.

  Below, the evaluation system which evaluates the image which a display apparatus displays using said optical measurement apparatus 1 is demonstrated.

  FIG. 6 is a configuration diagram showing the evaluation system of the present embodiment.

  As shown in FIG. 6, the evaluation system of this embodiment includes a light measurement device 1, a lighting device 2, and an image measurement device 3.

  The light measurement device 1 is provided for measuring the light distribution in space, and is the same as the light measurement device 1 described above. Then, the measurement data of the light distribution in the space measured by the light measurement device 1 is output to the illumination device 2.

  The illumination device 2 is provided to illuminate the display device to be evaluated. As illustrated in FIG. 6, the lighting device 2 includes an input unit 101, a lighting unit 102, and a control unit 103.

  The input unit 101 is provided for inputting measurement data of the light distribution in the space measured by the light measurement device 1. That is, the input unit 101 inputs, as measurement data, data related to the light distribution that is collected by the optical system 11 and generated by the detection data obtained by the photoelectric conversion element. The input unit 101 inputs, for example, luminance map information calculated by the calculation unit 41 of the light measurement device 1 as measurement data.

  The illumination unit 102 is provided to illuminate a display device that is an evaluation target.

  FIG. 7 is a diagram illustrating a main part of the illumination unit 102. 7A is a diagram illustrating a side surface of the illumination unit 102, FIG. 7B is a diagram illustrating a bottom side of the illumination unit 102, and FIG. 7C is a diagram illustrating the illumination unit. 2 is a partially enlarged view of a light source 102a provided in 102. FIG.

  As shown in FIGS. 7A and 7B, the illumination unit 102 has a hemispherical space. The illumination unit 102 accommodates a display device that is an evaluation target in the hemispherical space. The illumination unit 102 has an opening 102a formed at the top of the hemispherical space, and the image measurement device 3 is configured to measure the image characteristics of the display device from the opening 102a. Then, as in the case of the light measuring apparatus 1 described above, the illumination unit 102 includes 120 hemispherical spaces whose inner surfaces are divided into azimuth angles and incident angles by 15 °, as indicated by A1 to E24 in the figure. The light source 102b is arranged for each of the divided areas. In this way, a hemispherical space is formed by arranging the light sources 102b. As shown in FIG. 7C, each light source 102b is provided with an optical fiber 102d so that the light from the main light source 102c is individually introduced, and has a diffusion plate 102e that diffuses and reflects the light of the optical fiber 102d. However, it is configured such that planar light is emitted. In addition, a variable ND filter 102f is provided at the light entrance of the optical fiber 102d, and the amount of light from the light source 102b is adjusted by the variable ND filter 102f. Here, the light source 102b, which is a planar light source using an optical fiber, is shown, but a point light source such as a light bulb may be provided.

  The control unit 103 controls the illumination unit 102 based on the measurement data input from the input unit 101. The control unit 103 controls the light quantity of the light source 102a of the illumination unit 102 by adjusting each variable ND filter 102f based on the luminance map information input by the input unit 101, and the light distribution of the luminance map information. To reproduce.

  In addition, the input part 101 of the illuminating device 2 of this embodiment is corresponded to the input means of the illuminating device of this invention. Moreover, the illumination part 102 of the illuminating device 2 of this embodiment is corresponded to the illumination means of the illuminating device of this invention. And the control part 103 of the illuminating device 2 of this embodiment is corresponded to the control means of the illuminating device of this invention.

  The image measuring device 3 measures the image characteristics of the display device illuminated by the lighting device 2. The image measuring device 3 is composed of a luminance meter, for example. The image measuring device 3 is provided above the opening 102a of the illumination device 2, and measures the image characteristics of the display device from the opening 102a.

  Hereinafter, an evaluation method using the above evaluation system will be described.

  FIG. 8 is a flowchart of a method for measuring and evaluating the image characteristics of the display device using the above evaluation system.

  As shown in FIG. 8, first, the light distribution in a desired space is measured as described above using the light measurement device 1. For example, luminance map information is obtained as measurement data of spatial light distribution (ST111).

  Next, the display device to be evaluated is accommodated in the hemispherical space of the illumination unit 102 in the illumination device 2 (ST121).

  Next, measurement data of the light distribution in the space measured by the light measurement device 1 is input to the input unit 101 of the illumination device 2 to illuminate the display device (ST131). For example, luminance map information is input to the input unit 101 as measurement data. Then, based on the luminance map information input to the input unit 101 of the illumination device 2, the control unit 103 controls each light source 102b of the illumination unit 102, and the light distribution in the space obtained by the light measurement device 1 is reproduced.

  Next, the image characteristic of the display device illuminated by the illumination device 2 is measured using the image measurement device 3 (ST141). For example, the brightness of the display device in the reproduced space is measured using the image measuring device 3.

  As described above, according to the present embodiment, the optical measurement device 1 collects spatial light by the optical system 11, and the optical system 11 is formed by the photoelectric conversion unit 21 in which a plurality of photoelectric conversion elements are arranged. Each of the photoelectric conversion elements detects the collected light and converts it into detection data. Then, in the light measurement device 1, the calculation unit 41 calculates the light quantity based on the detection data to obtain a spatial light distribution. Here, the optical system 11 includes a wide-angle lens, and the calculation unit 41 calculates the luminance as the photometric quantity and obtains the luminance map information as the spatial light distribution. For this reason, this embodiment can easily measure the photometric value of a wide space in various real environments in a short time and easily obtain the light distribution.

  And according to this embodiment, the optical measurement apparatus 1 has the exposure amount control part 31 which controls the exposure amount to the photoelectric change element of the light condensed by the optical system 11. Then, the exposure amount control unit 31 controls the exposure amount to have a plurality of conditions, and the calculation unit 41 obtains a spatial light distribution based on the detection data acquired for the exposure amounts under the plurality of conditions. For this reason, since this embodiment can measure the photometric value of a wide range by controlling the exposure amount to a photoelectric change element, it can easily obtain the light distribution in various real environments.

  Further, according to the present embodiment, in the light measurement device 1, the calculation unit 41 divides the photoelectric conversion elements in the photoelectric conversion unit 21 into groups, and calculates the group photometric values based on the detection data corresponding to the groups. To do. For this reason, since this embodiment can calculate a photometric value in units of groups, even if noise is included in each detection data of the photoelectric conversion element, it is smoothed within the group, so an accurate light distribution Can be easily obtained.

  According to the present embodiment, the light measurement device 1 stores the correction coefficient of the photometric value corresponding to the incident angle of the light to the optical system 11 by the storage unit 51, and the calculation unit 41 stores the correction unit 41 by the storage unit 51. The light distribution is corrected based on the correction coefficient. For this reason, this embodiment respond | corresponds to a wide range space and can acquire an exact light distribution easily.

  Moreover, according to this embodiment, the illuminating device 2 is input from the input unit 101 that inputs measurement data of spatial light distribution, the illuminating unit 102 that illuminates the display device that is the object, and the input unit 101. And a control unit 103 that controls the illumination unit 102 based on the measurement data. Here, the illuminating device 2 collects the detection data obtained by the photoelectric conversion element as the measurement data to the input unit 101, like the data relating to the light distribution obtained by the light measurement device 1, by the optical system 11. Data generated by is used. For this reason, this embodiment can illuminate the object so as to reproduce the light distribution in the space in a pseudo manner.

  Further, according to the present embodiment, the evaluation system includes the light measurement device 1, the illumination device 2, and the image measurement device 3. The evaluation system of the present embodiment obtains measurement data of light distribution in a desired space by the light measurement device 1, reproduces the light distribution of the space by the illumination device 2, and displays the space in which the light distribution is reproduced. Are measured by the image measuring device 3. For this reason, this embodiment can easily measure and reproduce the light distribution in the real environment, and can easily evaluate the image characteristics of the display device.

FIG. 1 is a configuration diagram illustrating a main part of an optical measurement device according to an embodiment of the present invention. FIG. 2 is a flowchart of a measurement method for obtaining luminance map information by the light measurement device according to the embodiment of the present invention. FIG. 3 is a diagram showing luminance and gradation corresponding to the exposure amount in the light measurement apparatus according to the embodiment of the present invention. FIG. 4 is a diagram showing a result of luminance with respect to an incident angle of light to the optical system in the light measurement apparatus according to the embodiment of the present invention. FIG. 5 is a diagram illustrating how the photoelectric conversion elements of the photoelectric conversion unit 21 are divided into groups in the optical measurement device according to the embodiment of the present invention. FIG. 6 is a configuration diagram showing the evaluation system of the embodiment according to the present invention. FIG. 7 is a diagram illustrating a main part of the illumination unit of the illumination device in the evaluation system according to the embodiment of the present invention. FIG. 8 is a flowchart of a method for measuring and evaluating image characteristics of a display device using the evaluation system according to the embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Light measuring device, 2 ... Illuminating device, 3 ... Image measuring device, 11 ... Optical system, 21 ... Photoelectric conversion part, 31 ... Exposure amount control part, 41 ... Calculation part, 42 ... Correction | amendment part, 51 ... Memory | storage part, 61 ... Display unit, 101 ... Input unit, 102 ... Illumination unit, 102a ... Opening portion, 102b ... Light source, 103 ... Control unit

Claims (16)

A light measurement device for measuring light distribution in space,
An optical system for collecting the light in the space;
Photoelectric conversion means in which a plurality of photoelectric conversion elements that detect the light collected by the optical system and convert it into detection data are arranged;
A light measuring apparatus comprising: a calculating unit that calculates a light quantity based on detection data from the photoelectric conversion element to obtain a light distribution in the space. The light measurement apparatus according to claim 1, wherein the optical system includes a wide-angle lens. The light measurement device according to claim 1, wherein the calculation unit calculates a luminance as the light quantity, and obtains luminance map information as a light distribution in the space. The light measurement device according to claim 1, further comprising an exposure amount control unit that controls an exposure amount of the light collected by the optical system to the photoelectric change element. The exposure amount control means controls the exposure amount to be a plurality of conditions,
The light measurement apparatus according to claim 4, wherein the calculation unit obtains a light distribution in the space based on the detection data acquired for the exposure amount under the plurality of conditions. The light measurement apparatus according to claim 1, wherein the calculation unit divides the photoelectric conversion elements in the photoelectric conversion unit into groups and calculates a photometric value of the group based on the detection data corresponding to the group. The light measurement apparatus according to claim 1, further comprising display means for displaying a light distribution in the space generated by the calculation means. Storage means for storing a correction coefficient of a photometric value corresponding to an incident angle of light to the optical system;
The light measurement apparatus according to claim 1, further comprising: a correction unit that corrects the calculated light distribution based on a correction coefficient stored in the storage unit. An illumination device that illuminates an object so as to simulate a spatial light distribution,
Input means for inputting measurement data of the light distribution in the space;
Illumination means for illuminating the object;
Control means for controlling the illumination means based on the measurement data input from the input means,
The measurement data is data regarding the light distribution generated by detection data collected by an optical system and obtained by a photoelectric conversion element. The lighting device according to claim 9, wherein the measurement data is luminance map information in which an average value of luminance in each region divided into predetermined regions is converted into data. The illuminating device according to claim 9, wherein the illuminating unit has a hemispherical space, and a plurality of light sources for irradiating the display device with light are arranged on an inner surface of the hemispherical space. An evaluation system for evaluating an image displayed by a display device,
An illumination device for illuminating the display device;
An image measuring device for measuring image characteristics of the display device illuminated by the lighting device;
With
The lighting device includes:
Input means for inputting measurement data of the light distribution in the space;
Illumination means for illuminating the object;
Control means for controlling the illumination means based on the measurement data input from the input means,
The measurement system is data relating to the light distribution generated by detection data collected by an optical system and obtained by a photoelectric conversion element. An opening is formed in the illumination means,
The evaluation system according to claim 12, wherein the image measurement device measures image characteristics of the display device from an opening of the illumination unit. A light measuring device for measuring the light distribution in the space;
The light measuring device comprises:
An optical system for collecting the light in the space;
Photoelectric conversion means in which a plurality of photoelectric conversion elements that detect the light collected by the optical system and convert it into detection data are arranged;
The evaluation system according to claim 12, further comprising: a calculation unit that calculates a photometric amount based on detection data obtained by the photoelectric conversion element to obtain a light distribution in the space. The evaluation system according to claim 14, wherein the optical system includes a wide-angle lens. The evaluation system according to claim 14, wherein the calculation unit calculates a luminance as the light quantity, and obtains luminance map information as a light distribution in the space.

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