JP2019056687A - Glare evaluation device and glare evaluation method - Google Patents

Abstract

To propose a glare evaluation device that can quantitatively evaluate glaring of a display part of a display device having anti-glare processing applied by a simple method.SOLUTION: A glare evaluation device, which evaluates glare in a display part of a display device having anti-glare processing applied, comprises: an imaging device that photographs a display image displayed on a display part to obtain photographing data; an adjustment unit that adjusts a photographing size of the display image to be photographed per one pixel of an image pick-up element of the imaging device; and a glare measurement unit that obtains fluctuations of luminance, in the display image, correlating with a size of glare as a glare value indicative of the size of the glare on the basis of photographing data obtained by photographing the display image with the imaging device in a state with the photographing size adjusted by the adjustment unit. The adjustment unit is configured to make an adjustment in the photographing data so that the photographing size to be photographed per one pixel of the image pick-up element of the imaging device is equal to or more than 0.7 times a size of one pixel of the display image.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a glare evaluation apparatus and a glare evaluation method for quantitatively evaluating glare of a display unit included in a display device subjected to antiglare processing.

  In order to prevent external light from being reflected on the display unit, an antiglare film for mounting on the display unit has been developed. An anti-glare film is a film in which, for example, a surface of a transparent resin film is roughened to form a fine uneven surface, and external light is scattered and reflected on the uneven surface to reflect external light. Can be prevented. For example, a resin such as polyethylene terephthalate can be used as the base of the antiglare film. Moreover, as a formation method of an uneven surface, surface processing methods, such as a coating system, a sandblasting system, an embossing system, an etching system, are mentioned, for example.

  By the way, with the recent increase in the definition of pixels in a display unit, so-called glare, in which an image becomes difficult to see on a display unit equipped with an antiglare film, has been generated. The following two points can be considered as main causes of the occurrence of glare. First, the first point is that the light from the backlight is refracted by the uneven surface of the antiglare film and is visually recognized. The second point is that the pixel of the display unit is enlarged and visually recognized by the lens effect by the uneven surface of the antiglare film.

  Conventionally, the evaluation of glare in a display unit equipped with an antiglare film has generally been evaluated visually by an inspector. In such a subjective evaluation method by visual observation, there are problems that individual differences occur and quantitative evaluation is difficult.

  Thus, for example, Patent Documents 1 and 2 propose a glare evaluation apparatus that quantitatively evaluates the magnitude (glare value) of glare that occurs due to the wearing of an antiglare film. More specifically, the glare evaluation apparatus disclosed in Patent Documents 1 and 2 captures an image displayed on the display unit by an imaging unit, and after Fourier transforming the obtained image data, the structure unique to the display apparatus The periodic luminance unevenness derived from is removed, and the inverse Fourier transform is performed. And the glare evaluation apparatus disclosed by patent document 1, 2 performs the data process of an inverse Fourier transform image, and evaluates the dispersion | variation in the brightness | luminance by glare quantitatively.

Japanese Patent No. 3766342 JP 2009-175041 A

  However, the conventional techniques disclosed in Patent Documents 1 and 2 as described above have problems that the evaluation method is complicated and the evaluation is not performed in consideration of the combination of the antiglare film and the display device.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a glare evaluation apparatus capable of quantitatively evaluating the glare of a display unit included in a display device that has been subjected to anti-glare processing by a simple method. It is to provide a method for evaluating glare.

  A glare evaluation apparatus according to the present invention is a glare evaluation apparatus that evaluates glare in a display unit of a display device that has been subjected to anti-glare processing in order to solve the above-described problem, and the display displayed on the display unit An imaging device that captures image data by capturing an image, an adjustment unit that adjusts the imaging size of the display image that is captured per pixel of the imaging element of the imaging device, and the imaging size that has been adjusted by the adjustment unit A glare measuring unit for obtaining a variation in luminance in the display image correlated with the magnitude of the glare as a glare value indicating the magnitude of the glare, based on imaging data obtained by capturing the display image with the imaging device in a state; The adjustment unit is configured such that, in the imaging data, an imaging size captured per pixel of an imaging element of the imaging device is the display image. Adjusted to be 1 pixel size of 0.7 times or more.

  According to the above configuration, since the imaging apparatus and the glare measuring unit are provided, it is possible to obtain the luminance variation in the display image displayed on the display unit, which correlates with the magnitude of the glare. That is, glare can be evaluated quantitatively. In addition, as a method of obtaining the variation in luminance, for example, a method of obtaining a standard deviation of the luminance distribution, a method of obtaining by a differential product sum of the luminance distribution, or the like can be cited.

  In addition, since the adjustment unit is provided, in the imaging data, it is possible to adjust the imaging size captured per pixel of the imaging device of the imaging apparatus so that it is 0.7 times or more the size of one pixel of the display image. it can. For this reason, it is possible to adjust the imaging data so that the bright spot (brightness unevenness) of the pixel of the display image is not visible, or even if the bright spot of the pixel is visible, the glare evaluation is not affected. .

  Therefore, it is not necessary to perform the Fourier transform on the imaged data as in the prior art, remove the masked bright points caused by the pixels of the display image, and perform data processing on the inverse Fourier transform image obtained by performing the inverse Fourier transform. . That is, glare can be evaluated by a simple method compared to the prior art, and measurement processing related to the evaluation can be performed quickly. Moreover, since a measurement process can be performed quickly, it can be applied to, for example, in-line measurement.

  In addition, since the bright spot generated by the pixel of the display image is not removed from the captured image data by masking unlike the prior art, it is possible to prevent the information that causes glare together with the bright spot from being removed together. The glare evaluation is performed in consideration of, for example, the difference in the arrangement pattern of subpixels, which differs depending on the type of display device. For this reason, for example, when anti-glare processing is performed on the display unit by mounting the anti-glare film on the display unit, the evaluation is a glare considering a combination with a display device on which the anti-glare film is mounted. .

  In addition, the smaller the glare in the display image is, the lower the glare is, and the above-described method of the related art increases the proportion of missing information related to the size of the glare, and also regards the information related to the size of the glare as noise. There is a high possibility that it will end. For this reason, the evaluation accuracy of glare can be improved compared with the prior art.

  In addition, when the display unit to be evaluated for glare is a large display screen, the size of each pixel of the display image is increased, and the shape may be complicated for improving the visibility. In such a case, it is difficult to efficiently remove the bright spots generated by the pixels of the display image by the method using the Fourier transform as in the prior art. However, unlike the method of the prior art, the present application does not perform Fourier transform and the like, so that such a problem does not occur and can be applied to glare evaluation for a large display screen.

  Therefore, the glare evaluation apparatus according to the present invention has an effect that it is possible to quantitatively evaluate the glare of the display unit of the display device that has been antiglare processed by a simple method.

  Further, in the above-described configuration, the glare evaluation apparatus according to the present invention holds the imaging device movably so that the adjustment unit changes a relative distance between the display unit and the imaging device. And at least one of a display device pedestal that movably supports the display device so as to change a relative distance between the display unit and the imaging device. It may be a configuration.

  According to the above configuration, the adjustment unit includes at least one of an imaging device holding unit and a display device mount. For this reason, by changing the relative distance between the display unit of the display device and the imaging device, in the imaging data, the shooting size is 0.7 times or more the size of one pixel of the display image. Can be adjusted.

  Further, in the above-described configuration, the glare evaluation apparatus according to the present invention may be configured such that the adjustment unit includes a zoom lens that can change a focal length of the imaging apparatus.

  According to the above configuration, since the adjustment unit includes the zoom lens, by changing the focal length of the imaging device, the size of one pixel of the imaging data in the imaging data is 0 of the size of one pixel of the display image. It can be adjusted to be 7 times or more.

  Further, the glare evaluation apparatus according to the present invention has the above-described configuration, the imaging apparatus setting unit that sets the exposure time of the imaging apparatus, and the imaging apparatus that captures an image with the imaging size adjusted by the adjustment unit. A luminance determination unit that determines a luminance average value of the captured image data and determines whether or not the luminance average value matches a predetermined value, wherein the luminance determination unit sets the luminance average value to a predetermined value. If it is determined that they do not match, the correspondence between the brightness average value of the imaging data and the exposure time is obtained, and the exposure time is set so that the brightness average value of the imaging data matches a predetermined value. It may be configured.

  Here, the average luminance value of the imaging data is a value that is an average of the luminance of each pixel in the imaging data. The luminance is brightness information in a gray scale image in which one pixel is represented by 8 bits.

  According to the above configuration, since the luminance determination unit is provided, it is possible to determine whether or not the average luminance value of the imaging data matches a predetermined value. In addition, since the imaging device setting unit is provided, when the luminance average value does not match the predetermined value, the setting of the exposure time of the imaging device can be changed to set the luminance average value of the imaging data to the predetermined value.

  Therefore, in the glare evaluation apparatus according to the present invention, when evaluating the glare in the display unit, it is possible to adjust the luminance average of the captured image data captured by the imaging apparatus to be a predetermined value.

  Here, the luminance average of the imaging data and the magnitude of the luminance variation (glare value) show a positive correlation. For this reason, the glare evaluation apparatus according to the present invention can prevent the glare value from fluctuating due to the difference in the luminance average value in the imaging data when evaluating the glare in the display unit.

  A glare evaluation method according to the present invention is a glare evaluation method for evaluating glare in a display unit of a display device subjected to anti-glare processing, and is obtained by capturing a display image displayed on the display unit with an imaging device. First step of adjusting the captured image size of the display image captured per pixel of the image sensor of the image capturing device to be 0.7 times or more the size of one pixel of the display image in the captured image data And a second step of setting a measurement area that is an area for evaluating glare on the display unit, and the measurement area set in the second step in a state where the shooting size is adjusted in the first step. A third step of capturing a display image by the imaging device to obtain imaging data, and glare from the imaging data obtained in the third step. As glare value indicating the magnitude correlates to the size of the glare, and a fourth step of obtaining a variation in luminance of the display image of the measurement area.

  According to the above method, the variation in luminance of the display image in the measurement area, which correlates with the size of the glare in the measurement area, can be obtained as the glare value. That is, the glare in the measurement area can be quantitatively evaluated as the glare value. In addition, as a method of obtaining the variation in luminance, for example, a method of obtaining a standard deviation of the luminance distribution, a method of obtaining by a differential product sum of the luminance distribution, or the like can be cited.

  Further, in the imaging data, the size of the imaging data can be adjusted to be 0.7 times or more the size of one pixel of the display image. For this reason, it is possible to adjust the imaging data so that the bright spot (brightness unevenness) of the pixel of the display image is not visible, or even if the bright spot of the pixel is visible, the glare evaluation is not affected. .

  Therefore, it is not necessary to perform the Fourier transform on the imaged data as in the prior art, remove the masked bright points caused by the pixels of the display image, and perform data processing on the inverse Fourier transform image obtained by performing the inverse Fourier transform. . That is, glare can be evaluated by a simple method compared to the prior art, and measurement processing related to the evaluation can be performed quickly. Moreover, since a measurement process can be performed quickly, it can be applied to, for example, in-line measurement.

  In addition, since the bright spot generated by the pixel of the display image is not removed from the captured image data by masking unlike the prior art, it is possible to prevent the information that causes glare together with the bright spot from being removed together. The glare evaluation is performed in consideration of, for example, the difference in the arrangement pattern of subpixels, which differs depending on the type of display device. For this reason, for example, when anti-glare processing is performed on the display unit by mounting the anti-glare film on the display unit, the evaluation is a glare considering a combination with a display device on which the anti-glare film is mounted. .

  In addition, the smaller the glare in the display image is, the lower the glare is, and the above-described method of the related art increases the proportion of missing information related to the size of the glare, and also regards the information related to the size of the glare as noise. There is a high possibility that it will end. For this reason, the evaluation accuracy of glare can be improved compared with the prior art.

  In addition, when the display unit to be evaluated for glare is a large display screen, the size of each pixel of the display image is increased, and the shape may be complicated for improving the visibility. In such a case, it is difficult to efficiently remove the bright spots generated by the pixels of the display image by the method using the Fourier transform as in the prior art. However, unlike the method of the prior art, the present application does not perform Fourier transform or the like, and thus can be applied to a glare evaluation for a large display screen without causing such a problem.

  Therefore, the glare evaluation method according to the present invention has an effect that it is possible to quantitatively evaluate the glare of the display unit of the display device that has been antiglare processed by a simple method.

  Further, the glare evaluation method according to the present invention is the above-described method, in which the display image of the measurement area is captured by the imaging device after performing the second step and before performing the third step. The average brightness value is obtained from the obtained imaging data, the exposure time setting of the imaging device is changed so that the average brightness value matches a predetermined value, and the average brightness value of the imaging data is adjusted. A fifth step may be further included.

  Here, the average luminance value of the imaging data is a value that is an average of the luminance of each pixel in the imaging data. The luminance is brightness information in a gray scale image in which one pixel is represented by 8 bits.

  According to the above method, the setting of the exposure time of the imaging apparatus can be changed to adjust the brightness average value of the imaging data. For this reason, the brightness average value of the imaging data can be set to a predetermined value.

  Here, the luminance average value of the imaging data and the magnitude of the luminance variation (glare value) show a positive correlation. For this reason, the glare evaluation method according to the present invention can prevent the glare value from fluctuating due to the difference in the luminance average value in the imaging data when evaluating the glare in the display unit.

  According to the present invention, it is possible to quantitatively evaluate the glare of the display unit of the display device that has been antiglare processed by a simple method.

It is a figure which shows an example of schematic structure of the glare evaluation apparatus which concerns on embodiment of this invention. It is a figure which shows typically the relationship between the imaging size of 1 pixel of imaging data, and the size of 1 pixel of a display image in imaging data. In imaging data, when a bright spot (luminance unevenness) due to a pixel of a display image is visible (or not visible), the shooting size per pixel of the imaging data and the size of one pixel of the display image (one pixel pitch) ). It is a figure which shows an example of the imaging data imaged with the imaging device which concerns on embodiment of this invention, The figure (a) is the imaging | photography size per pixel of imaging data being 0 of the size of 1 pixel of a display image. .B shows the imaging data when the imaging size per pixel of the imaging data is 0.74 times the size of one pixel of the display image. . It is a graph which shows an example of the relationship between the ratio of the size of 1 pixel of imaging data, and the size of 1 pixel of a display image, and the luminance distribution in imaging data. It is a flowchart which shows an example of the glare evaluation method implemented using the glare evaluation apparatus shown in FIG. It is a graph which shows an example of the correspondence of the value of the average brightness of the imaging data imaged with the imaging device of the glare evaluation apparatus concerning the embodiment of the present invention, and the size of glare. It is a graph which shows an example of the correspondence of the brightness average value of the imaged data imaged by the imaging device of the glare evaluation device concerning the embodiment of the present invention, and the exposure time of the imaging device. It is a flowchart which shows an example of the luminance adjustment process in the glare evaluation apparatus which concerns on embodiment of this invention. It is a bar graph which shows the correspondence of the value of the standard deviation regarding the luminance distribution of the image displayed on the display part equipped with the anti-glare film in Example 1 of this invention, and a sample from which sensory evaluation results differ, respectively. In Example 2 of this invention, it is a bar graph which shows the correspondence of the value of the standard deviation regarding the luminance distribution of the image displayed on the two types of display parts equipped with the anti-glare film, and the samples with different sensory evaluation results. . In Example 3 of the present invention, the value of the standard deviation regarding the luminance distribution of the image displayed on the display unit when the antiglare film is mounted via the double-sided tape and when the double-sided tape is not used, and sensory evaluation Is a bar graph showing the correspondence with different samples. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram used for explaining a process leading to an embodiment of the present invention, and FIGS. 2A and 2B are diagrams illustrating an example of an array pattern of subpixels in a display unit.

(Background to obtaining one embodiment of the present invention)
The present inventors diligently studied about the evaluation of glare in a display portion that has been subjected to antiglare processing. In particular, the evaluation of the glare in the display portion equipped with the antiglare film was examined. For example, the anti-glare film has a different uneven pitch depending on its type. On the other hand, as shown in FIGS. 13A and 13B, the display units included in the display device have different subpixel arrangement patterns depending on the model of the display device. Therefore, the glare degree is influenced by the difference in the arrangement pattern of the subpixels in the display portion and the difference in the uneven shape of the antiglare film. For this reason, the present inventors have noticed that it becomes possible to correlate with visual glare evaluation for the first time by evaluating the glare by combining the display portion and the antiglare film. And both about the case where the anti-glare film having different uneven shapes is attached to the display portion of the same type of display device and the case where the same anti-glare film is attached to each of the display portions of the plurality of types of display devices It has been found that it is preferable that glare can be evaluated by the same evaluation method. FIGS. 13A and 13B are diagrams used for explaining the process of obtaining one embodiment of the present invention, and FIGS. 13A and 13B are diagrams showing an example of an array pattern of subpixels in a display unit. is there. A combination of R, G, and B sub-pixels is defined as one pixel of the display image.

  Here, the glare evaluation apparatus disclosed in Patent Documents 1 and 2 (hereinafter referred to as a conventional glare evaluation apparatus) captures a display image displayed on the display unit by an imaging unit, and Fourier-transforms the obtained imaging data. Thereafter, periodic luminance unevenness (bright spots) caused by the pixels of the display image is removed by masking, and inverse Fourier transform is performed. And it was the structure which evaluates glare by data-processing an inverse Fourier-transform image. By this structure, the conventional glare evaluation apparatus can evaluate the glare resulting from the uneven | corrugated shape which an anti-glare film has.

  However, as described above, the conventional glare evaluation apparatus is configured to remove periodic luminance unevenness caused by pixels of a display image from captured image data. For this reason, in the conventional glare evaluation apparatus, for example, the evaluation result does not take into consideration the difference for each model of the display device such as the difference in the arrangement pattern of the subpixels. In addition, the bright spot masked in the Fourier transform image includes information that causes glare. For this reason, when the inverse Fourier transform is performed while masking the bright spot, information that causes glare is also removed. Therefore, this method cannot essentially perform accurate glare evaluation. Therefore, it is considered that the evaluation results of Patent Documents 1 and 2 do not correlate with the result of visual sensory evaluation of glare for various types of display devices to which an antiglare film is attached.

  Accordingly, the present inventors have studied a glare evaluation apparatus that can quantitatively evaluate glare and obtain an evaluation result correlating with sensory evaluation against glare, and as a result, has reached the present invention.

  Hereinafter, a glare evaluation apparatus according to an embodiment of the present invention will be described with reference to the drawings. In the following description, the same or corresponding elements are denoted by the same reference symbols throughout all the drawings, and redundant description thereof is omitted.

(Configuration of glare evaluation device)
First, with reference to FIG. 1, the principal part structure of the glare evaluation apparatus 1 which concerns on embodiment of this invention is demonstrated. FIG. 1 is a diagram illustrating an example of a schematic configuration of a glare evaluation apparatus 1 according to an embodiment of the present invention. The glare evaluation device 1 is an evaluation device that evaluates glare in the display unit of the display device 7 that has been subjected to antiglare processing. Examples of the display unit of the display device 7 that has been subjected to anti-glare processing include an aspect in which the display screen of the display unit is formed of AG glass, an aspect in which an anti-glare film is attached to the display unit, and the like. In the embodiment of the present invention, a method for evaluating glare in the display unit of the display device 7 that has been subjected to anti-glare processing will be described by taking an example in which an anti-glare film is attached to the display unit.

  As shown in FIG. 1, the glare evaluation device 1 includes a housing 2, an imaging device 3, an imaging device holding unit (adjustment unit) 4, an imaging device platform 5, a display device platform (adjustment unit) 6, and a display device 7. , And a main control unit 8.

  The housing 2 is for forming a dark room as an inspection space for performing glare evaluation, and has a hollow rectangular parallelepiped shape. In the housing 2, an imaging device 3, an imaging device holding unit 4, an imaging device gantry 5, a display device gantry 6, and a display device 7 are accommodated. In addition, the housing | casing 2 should just be formed from the material which has the intensity | strength required in order to accommodate these each part, and can prevent the entrance of the light into the housing | casing 2 from the exterior.

  The imaging device 3 is an area camera having a lens 3 a and an imaging device for capturing an image displayed on the display unit of the display device 7, and the captured imaging data is provided outside the housing 2. It is transmitted to the main control unit 8. The imaging device 3 is positioned directly above the display device 7 and is held by the imaging device holding unit 4 so that the lens 3a and the display unit of the display device 7 face each other.

  The imaging device holding unit 4 holds the imaging device 3 movably in the vertical direction (vertical direction) on the paper surface of FIG. 1 so as to change the relative distance between the display device 7 and the imaging device 3. It has a bar shape extending in the vertical direction. The imaging device 3 is held on the distal end side of the imaging device holding unit 4, while the proximal end side is fixed by the imaging device mount 5. Thus, since the imaging device 3 can be moved in the vertical direction by the imaging device holding unit 4, the relative positional relationship between the imaging device 3 and the display unit of the display device 7 is adjusted. can do. The movement of the imaging device 3 by the imaging device holding unit 4 may be configured to be performed by driving a motor or the like, or may be configured to be performed manually. Note that the adjustment unit of the present invention can be realized by the imaging device holding unit 4 and the display device mount 6 described later. The distance between the imaging device 3 and the display device 7 is preferably set in consideration of the actual use environment of the display device 7.

  In the embodiment of the present invention, as shown in FIG. 1, since the imaging device 3 is disposed directly above the display device 7, the moving direction of the imaging device 3 by the imaging device holding unit 4 is the vertical direction. It has become. However, depending on the positional relationship between the display device 7 and the imaging device 3, the moving direction of the imaging device 3 is different. For example, when the imaging device 3 and the display device 7 are arranged so as to face each other in the horizontal direction (the left-right direction in the drawing of FIG. 1), the moving direction of the imaging device 3 is the horizontal direction. That is, the imaging device holding unit 4 can move in a direction in which the imaging device 3 is brought closer to the display device 7 or away from the display device 7 so that a distance between the imaging device 3 and the display device 7 is variable. It only has to be.

  Further, the imaging device holding unit 4 not only moves in the vertical direction so that the distance between the imaging device 3 and the display device 7 is variable, but also includes a measurement area and an imaging device for evaluating glare in the display device 7. The imaging apparatus 3 may be configured to be movable in the horizontal direction so that the position 3 faces the position 3.

  The display device 7 is an object to be evaluated for glare evaluation, and although not shown, an anti-glare film is attached to the display unit of the display device 7. The display device 7 is placed on the upper surface of the display device mount 6.

  The display device stand 6 supports the display device 7 so that the main surface (the surface on which the display unit is provided) faces the imaging device 3 and is in a horizontal plane, and moves the display device 7 in the vertical direction. Can be made. The display device stand 6 may be configured to move by driving a motor or the like, or may be configured to move manually. The moving direction of the display device 7 by the display device mount 6 is also determined by the positional relationship between the display unit and the imaging device 3 in the same manner as the moving direction of the imaging device 3 by the imaging device holding unit 4 described above.

  Further, the display device stand 6 not only moves in the vertical direction so that the distance between the image pickup device 3 and the display device 7 is variable, but also includes a measurement area and an image pickup device for evaluating glare in the display device 7. The display device 7 may be configured to be movable in the horizontal direction such that the display device 7 faces the position 3.

  As described above, in the glare evaluation apparatus 1, the imaging device 3 and the display are displayed by the movement of the imaging device 3 by the imaging device holding unit 4 (adjustment unit) and the movement of the display device 7 by the display device mount 6 (adjustment unit). The relative distance from the display unit of the device 7, that is, the relative positional relationship between the two can be adjusted with high accuracy. Then, by adjusting the relative distance between the imaging device 3 and the display unit of the display device 7 by the adjustment unit described above, the display image (display) displayed on the display unit by the imaging device 3 (imaging element) is displayed. The size of the image (pixel) is adjusted. In other words, by adjusting the relative distance between the imaging device 3 and the display unit of the display device 7 by the adjustment unit, the shooting size that is the size of the display image captured by the imaging device 3 is adjusted. Specifically, in the imaging data captured by the imaging device 3, imaging that is captured per pixel of the imaging element of the imaging device 3 so that bright spots (luminance unevenness) due to the pixels of the display image do not appear. The size of the target (display image) (photographing size per pixel of the imaging data) is adjusted to be 0.7 times or more the size of one pixel of the display image.

  As shown in FIG. 2, the shooting size (size Y) per pixel of the imaging data means the size of the captured display image corresponding to the size of one side of one pixel of the imaging data. . On the other hand, the size of one pixel (size X) of the display image means the size of one side of one pixel of the display image. When one pixel of the imaging data and one pixel of the display image are not square, each size may be the size of one side in each horizontal direction or vertical direction. FIG. 2 is a diagram schematically illustrating the relationship between the imaging size per pixel of the imaging data and the size of one pixel of the display image in the imaging data. In the glare evaluation apparatus 1 according to the embodiment of the present invention, the shooting size (size Y) per pixel of the captured image data is 0.7 times or more, preferably 0.8 times the size (size X) of one pixel of the display image. It is adjusted to be 75 times or more, more preferably 0.8 times or more, particularly preferably 1.0 times or more.

  Alternatively, the photographing size (size Y) per pixel of the imaging data in the horizontal direction and the vertical direction is 0.7 times or more the size (size X) of one pixel of the display image in the horizontal direction and the vertical direction, preferably May be adjusted to be 0.75 times or more, more preferably 0.8 times or more, and particularly preferably 1.0 times or more.

  Further, the adjustment of the ratio between the shooting size per pixel of the imaging data and the size of one pixel of the display image can be performed as follows, for example. First, a grid-like sheet in which a plurality of saddles each having a side of 1 cm is arranged on the display unit. Then, the display unit is imaged by the imaging device 3, and in the obtained imaging data, one pixel of the imaging data is obtained by determining how many pixels in the imaging data corresponds to one side (1 cm) of each imaged image. The per shot size (size Y) can be calculated. For example, when one side (1 cm) of each captured eyelid corresponds to 200 pixels in the imaging data, the size Y = 50 μm (= 1 cm / 200) can be calculated.

  Here, the size of one pixel of the display image displayed on the display unit is known in advance by the display device. Therefore, in the glare evaluation apparatus 1, the per-pixel image data is set so that the image-capturing size (size Y) per pixel of the image data is 0.7 times or more the size (size X) of one pixel of the display image. Adjust the ratio between the shooting size and the size of each cell of the checkered sheet.

  As described above, in the glare evaluation apparatus 1 according to the embodiment of the present invention, the imaging size (size Y) per pixel of the imaging data and the size (size X) of one pixel of the display image in the imaging data. The ratio can be adjusted. Note that this adjustment is not limited to the method described above, and in the imaging data, the shooting size per pixel of the imaging data and the size of one pixel of the display image have the desired relationship described above. There is no particular limitation as long as it can be adjusted. Further, in the imaging data, a detailed description on the basis for setting the imaging size per pixel of the imaging data to 0.7 times or more the size of one pixel of the display image will be described later.

  The main control unit 8 performs various controls of each unit included in the glare evaluation apparatus 1, and includes a glare measurement unit 10, a luminance determination unit 11, an imaging device setting unit 12, and a storage unit 13.

  The glare measurement unit 10 obtains the value of the standard deviation of the luminance of the display image of the captured display unit based on the imaging data obtained by the imaging device 3. Note that the glare measurement unit 10 may further obtain a value (glaring rate) obtained by dividing the obtained standard deviation value by the luminance average (gradation). The glare rate calculated | required here is represented as inclination of the graph shown in FIG. 7 mentioned later. Based on the glare rate, it is possible to obtain an index of the ease of occurrence of glare in the combination of the display unit of the display device 7 and the antiglare film attached to the display unit. For this reason, when it is set as the structure which the glare measuring part 10 calculates | requires a glare rate further, the evaluation of the pros and cons of the combination of an anti-glare film and the display part of the display apparatus 7 can be performed regarding the ease of generating glare. Moreover, when the display device 7 is specified, it is possible to evaluate the glare performance (ease of glare) of the antiglare film attached to the display unit of the display device 7.

  The luminance determination unit 11 obtains a luminance average value of the display image of the captured display unit based on the imaging data, and determines whether or not the luminance average value matches a predetermined value. If the average brightness value does not match the predetermined value in this determination, the brightness determination unit 11 instructs the imaging device setting unit 12 to change the exposure time setting of the imaging device 3. The luminance average value is a value that is an average of the luminance of each pixel in the imaging data. The luminance is brightness information in a grace scale image in which one pixel is represented by 8 bits.

  The imaging device setting unit 12 controls various settings of the imaging device 3. For example, when an instruction regarding the setting of the exposure time is received from the luminance determination unit 11, the setting of the exposure time of the imaging device 3 is changed.

  The storage unit 13 is a data readable / writable recording medium in which data necessary for the main control unit 8 to control the glare evaluation apparatus 1 is recorded. The storage unit 13 also records exposure time adjustment data described later.

  Although not particularly shown in FIG. 1, the main control unit 8 outputs an input unit to which imaging data captured by the imaging device 3 is input, and processing results for the imaging data to a display device or a printing device (not illustrated). An output unit or the like may be provided.

  As described above, the glare evaluation apparatus 1 according to the embodiment includes the imaging device holding unit 4 and the display device mount 6 as the adjustment unit of the present invention, and the relative relationship between the imaging device 3 and the display unit of the display device 7. The correct distance. Then, by adjusting the relative distance between the imaging device 3 and the display unit of the display device 7, the relationship (ratio) between the imaging size per pixel of the imaging data and the size of one pixel of the display image is adjusted. Was configured.

  However, when the relative distance between the imaging device 3 and the display unit of the display device 7 can be adjusted to an appropriate distance only by the imaging device holding unit 4, the imaging device holding unit is used as the adjustment unit of the present invention. 4 may be provided. Alternatively, when the relative distance between the imaging device 3 and the display unit of the display device 7 can be adjusted to be an appropriate distance using only the display device stand 6, the display device stand is used as the adjustment unit of the present invention. 6 may be provided.

  Further, the adjustment of the ratio between the imaging size per pixel of the imaging data and the size of one pixel of the display image is a method of changing the relative distance between the imaging device 3 and the display unit of the display device 7. It is not limited. For example, when the lens 3 a included in the imaging device 3 is a zoom lens, the adjustment may be made by changing the focal length of the imaging device 3. In the case of this configuration, the adjustment unit of the present invention is realized by the lens 3a.

  In the embodiment of the present invention, a display of a smartphone is described as an example of the display unit of the display device 7 to be evaluated for glare evaluation, but the display device 7 is not limited to a smartphone. For example, the display unit of the display device 7 may be a liquid crystal display such as a computer or a television, a plasma display, an organic EL display, or the like.

(Presence or absence of luminance unevenness due to display image pixels)
Here, the present inventors diligently studied whether or not bright spots (luminance unevenness) due to the pixels of the display image appear and do not appear in the imaging data captured by the imaging device 3. As a result, as shown in FIG. 3, when the ratio of the shooting size (size Y) per pixel of the imaging data to the size (size X) of one pixel of the display image is set to a value within a predetermined range, the imaging data In other words, the inventors have found that no bright spots (luminance unevenness) due to the pixels of the display image appear. Specifically, when the value of size Y / size X is adjusted to a value in the range of 0.7 or more, the knowledge that bright spots (luminance unevenness) due to the pixels of the display image do not appear in the imaging data Got. In addition, the upper limit of the range of values that can be taken by size Y / size X at this time can be 11. This upper limit value can be set as the size of one pixel of the display image when the resolution becomes higher in the future, the resolution of the imaging device 3, and the distance between the imaging device 3 and the display unit of the display device 7. It can be set as appropriate depending on the range. For example, when the display unit of the display device 7 is, for example, a smartphone having a screen size of 4 inches and a resolution of 300 ppi or more as in the embodiment of the present invention, as described above, the value that the size Y / size X can take. The upper limit value of the range can be 11. On the other hand, when the display unit of the display device 7 is, for example, a tablet PC having a screen size of 9.7 inches and a resolution of 200 ppi to 300 ppi, the upper limit of the range of values that the size Y / size X can take is 5. can do. Further, when the display unit of the display device 7 is a 4K television having a screen size of 40 inches and a resolution of 100 ppi or less, for example, the upper limit of the range of values that the size Y / size X can take is 1.5. Good.

  Note that FIG. 3 shows the captured size (μm) per pixel of the image data and the display image when the bright spot (luminance unevenness) due to the pixel of the display image is visible (or not visible) in the image data. It is a graph which shows the relationship with the size (1 pixel pitch) (micrometer) of 1 pixel. In FIG. 3, “◯” indicates a case in which bright spots (luminance unevenness) due to pixels of the display image do not appear in the imaging data, and “×” indicates a bright spot (luminance) due to the pixels of the display image. This shows the case where unevenness appears. In FIG. 3, the vertical axis indicates the shooting size (μm) per pixel of the imaging data. In other words, the size (μm) of the display image captured per pixel of the image sensor of the imaging device 3 is shown. The horizontal axis indicates the pixel pitch of the display image (distance between the centers of adjacent pixels in the display image), in other words, the size of one pixel of the display image.

  That is, when the size of one pixel of the display image is an arbitrary size, the size of the display image captured per pixel of the image sensor (per pixel of the imaging data) with respect to the size of one pixel of the display image. The relative distance between the display unit of the display device 7 and the imaging device 3 is adjusted so that the (photographing size) gradually increases or decreases, and the relative distance between the display unit and the imaging device 3 is different. The presence or absence of bright spots (luminance unevenness) at each point was confirmed visually. As a result, when the photographing size value per pixel of the imaging data is within a certain range, a bright spot (luminance unevenness) appears in the imaging data, and when it exceeds the range, the bright spot (luminance unevenness) does not appear. I understood. As a result of performing this operation for each display image having a different size of one pixel, the relationship between the shooting size (Y) per pixel of the captured image data and the size (X) of one pixel of the display image is Y = 0.7X. It has been found that the time when the condition is satisfied is a threshold value for discriminating whether or not a bright spot (luminance unevenness) due to the pixel of the display image appears.

  For example, as shown in FIG. 4A, when the shooting size per pixel of the imaging data is 0.52 times the size of one pixel of the display image (that is, smaller than 0.7 times). In the image data, periodic bright spots (luminance unevenness) appeared. On the other hand, as shown in FIG. 4B, when the shooting size per pixel of the imaging data is 0.74 times the size of one pixel of the display image (that is, 0.7 times or more). , Periodic bright spots (brightness unevenness) did not appear in the imaging data. FIG. 4 is a diagram illustrating an example of imaging data captured by the imaging device 3 according to the embodiment of the present invention. FIG. 4A illustrates that the imaging size per pixel of the imaging data is 1 of the display image. The imaging data when the pixel size is 0.52 times is shown, and FIG. 5B shows when the imaging size per pixel of the imaging data is 0.74 times the size of one pixel of the display image. The imaging data of is shown.

  Further, as shown in FIG. 5, the luminance distribution in the imaging data was examined by changing the ratio between the imaging size per pixel of the imaging data and the size of one pixel of the display image. FIG. 5 is a graph showing an example of the relationship between the ratio between the shooting size per pixel of the imaging data and the size of one pixel of the display image and the luminance distribution in the imaging data. In FIG. 5, the horizontal axis indicates luminance (8-bit gradation), and the vertical axis indicates frequency.

  That is, as shown in FIG. 5, when the shooting size per pixel of the imaging data is 0.52 times the size of one pixel of the display image, when it becomes 0.58 times, it becomes 0.65 times. When it becomes 0.71 times and 0.74 times, the luminance distribution was examined for each. At this time, two peaks appeared in the luminance distribution when the imaging size per pixel of the imaging data is 0.52, 0.58, and 0.65 times the size of one pixel of the display image. However, only one peak appeared in the luminance distribution when 0.71 and 0.74 times. This is because when the shooting size per pixel of the imaging data is smaller than 0.7 times the size of one pixel of the display image, the bright spots (brightness unevenness) appearing periodically become dominant, and the luminance distribution is 2 One peak appears to have appeared. On the other hand, when the shooting size per pixel of the imaging data is 0.7 times or more the size of one pixel of the display image, the display image is not affected by the bright spot (brightness unevenness), and the luminance caused by glare It can be judged that it is only.

  In FIG. 3 described above, when an organic EL display is used as the display unit of the display device 7 to be imaged, when a bright spot (luminance unevenness) due to a pixel of the display image is visible (or not visible). ) Was evaluated. In addition, it evaluated also about the case where the liquid crystal display from which the arrangement pattern of a sub pixel differs from an above-mentioned organic EL display as a display part of the display apparatus 7 was used. As a result, as in the case where the display unit of the display device 7 is an organic EL display, the shooting size (Y) per pixel of the imaging data and the size (X) of one pixel of the display image are Y = 0.7X. It has been found that the time when the relationship is satisfied is a threshold value that makes it possible to discriminate whether or not bright spots (luminance unevenness) due to the pixels of the display image appear. That is, an evaluation result similar to the evaluation shown in FIG. 3 was obtained. As a result, regardless of the difference in display form and subpixel arrangement, the above-described threshold value Y is used as a threshold value for discriminating whether or not bright spots (luminance unevenness) due to the pixels of the display image appear in the imaging data. = 0.7X relationship was established.

  As described above, in the glare evaluation apparatus 1 according to the embodiment of the present invention, the imaging apparatus 3 and the display are displayed so that the imaging size per pixel of the imaging data is 0.7 times or more the size of one pixel of the display image. It turned out that glare can be evaluated appropriately by adjusting the relative distance with the display part of the apparatus 7. FIG.

  In addition, since the size of one pixel of the display image is too large or too small, in the lens 3a provided as a default in the imaging device 3, the shooting size per pixel of the imaging data is the size of one pixel of the display image. It is also conceivable that the adjustment cannot be made to be 0.7 times or more. In such a case, the glare evaluation apparatus 1 may be configured such that the lens 3a can be replaced with another lens having a different magnification.

(Glare evaluation method)
Next, with reference to FIG. 6, the glare evaluation method by the glare evaluation apparatus 1 which has an above-described structure is demonstrated. FIG. 6 is a flowchart showing an example of the glare evaluation method performed using the glare evaluation apparatus 1 shown in FIG. In this glare evaluation method, a smartphone equipped with an antiglare film is used as the display device 7, and the display on the display device 7 displays the light emitting surface uniformly for convenience of evaluation, for example, a green color display and the like. To do. Note that the display on the display unit is not limited to this one-color display, and may be configured to display another color such as white.

  First, in the imaging data captured by the imaging device of the imaging device 3, the imaging size per pixel of the imaging data is adjusted to be a predetermined size with respect to the size of one pixel of the display image (step S11). . That is, the relative distance between the imaging device 3 and the display unit of the display device 7 is adjusted, and the display image displayed on the display unit of the display device 7 in the imaging data captured by the imaging device of the imaging device 3 Adjustment is made so that a bright spot (brightness unevenness) due to the pixel is not visible or even if the brightness unevenness is visible, the glare evaluation is not affected.

  As described above, when the present inventors examined through an experiment, in the imaging data, the imaging device so that the imaging size per pixel of the imaging data is 0.7 times or more the size of one pixel of the display image. It has been found that the relative distance between 3 and the display unit of the display device 7 may be adjusted. Therefore, in step S11, the imaging data is adjusted so that the imaging size per pixel of the imaging data is 0.7 times or more the size of one pixel of the display image.

  In step S11, after adjusting the imaging size per pixel of the imaging data to be 0.7 times or more the size of one pixel of the display image, a measurement area is set (step S12). The measurement area is an area where glare is evaluated in the display unit, and is appropriately set according to the size of the display unit of the display device 7 to be evaluated.

  Next, a display image in the measurement area is imaged by the imaging device 3 (step S13), and the obtained imaging data is input to the glare measurement unit 10 included in the main control unit 8. The glare measurement unit 10 obtains the variation in luminance of the display image displayed in the measurement area from the input imaging data (step S14). The variation in luminance can be quantified by, for example, obtaining a standard deviation of the luminance distribution. Further, the relationship between the luminance variation degree and the glare value indicating the glare degree of the display image on the display unit is such that the smaller the standard deviation value, the smaller the glare value. The variation in luminance is not limited to the method for obtaining the standard deviation of the luminance distribution. For example, the product-sum operation (differential product) that obtains the differential value of the luminance in each pixel and calculates the sum of the differential values of all the pixels. The sum may be obtained. In addition to the standard deviation of the luminance distribution, the glare measuring unit 10 may further obtain a value (glaring rate) obtained by dividing the standard deviation value by the luminance average (gradation). Based on the glare rate, it is possible to obtain an index of the ease of occurrence of glare in the combination of the display unit of the display device 7 and the antiglare film attached to the display unit. For this reason, it is possible to evaluate the pros and cons of the combination of the antiglare film and the display unit of the display device 7 with regard to the ease of glare. Moreover, when the display device 7 is specified, it is possible to evaluate the glare performance (ease of glare) of the antiglare film attached to the display unit of the display device 7.

  By the way, the inventors of the present invention have shown that the magnitude of the luminance of the image data of the display image taken by the imaging device 3 (the magnitude of the luminance average value) and the standard deviation (glare value) of the luminance distribution are as shown in FIG. It was found that there is a positive correlation as shown in FIG. FIG. 7 is a graph showing an example of the correspondence relationship between the average brightness value and the glare value of the image data captured by the imaging device 3 of the glare evaluation apparatus 1 according to the embodiment of the present invention. In the graph of FIG. 7, the horizontal axis indicates the average luminance value (8-bit gradation), and the vertical axis indicates the standard deviation (glare value) of the luminance distribution of the display image.

  For this reason, when comparing the size of the glare for each of the display images displayed on the plurality of types of display devices 7, it is necessary to make the size of the luminance average value of the imaging data captured by the imaging device 3 constant. I found out. Further, as shown in FIG. 8, the present inventors have found that the exposure time (μ seconds) in the imaging device 3 and the luminance average value have a positive correlation, and the exposure time of the imaging device 3 is determined. It has been found that the brightness average value can be adjusted by adjusting. FIG. 8 is a graph illustrating an example of a correspondence relationship between the average brightness value of the image data captured by the imaging device 3 of the glare evaluation device 1 according to the embodiment of the present invention and the exposure time of the imaging device 3.

  Based on these findings, the inventors adjust the setting of the exposure time of the imaging device 3 so that the luminance average value of the imaging data becomes a predetermined value when evaluating the glare in the display unit of the display device 7. It came to the idea that it was suitable to be the structure which can be performed.

  Specifically, the main control unit 8 stores in the storage unit 13 data (exposure time adjustment data) indicating a correspondence relationship between the average brightness value of the imaging data illustrated in FIG. 8 and the exposure time of the imaging device 3. Keep it. The correspondence relationship between the average brightness value of the imaging data and the exposure time of the imaging device 3 differs for each display unit of the display device 7 to be imaged. For this reason, the storage unit 13 stores exposure time adjustment data for each display device 7 to be evaluated for glare in advance. And it is good also as a structure which implements the luminance adjustment process shown in FIG. 9 after step S12 and before step S13. Hereinafter, the brightness adjustment processing will be described with reference to FIG. FIG. 9 is a flowchart showing an example of the brightness adjustment process in the glare evaluation apparatus 1 according to the embodiment of the present invention.

  First, after setting the measurement area in step S12, the image pickup data of the measurement area is experimentally acquired by the image pickup apparatus 3 (step S21). Then, the luminance determination unit 11 obtains a luminance average value from the imaging data (step S22), and determines whether the obtained luminance average value matches a predetermined value (step S23). Here, when the luminance determination unit 11 determines that the obtained average luminance value does not match the predetermined value (“YES” in step S23), the exposure time adjustment stored in the storage unit 13 by the imaging device setting unit 12 Based on the data, the exposure time set in the imaging device 3 is changed (step S24). Specifically, the imaging device setting unit 12 refers to the exposure time adjustment data, and changes the exposure time setting so that the average brightness value of the imaging data matches a predetermined value. As described above, the glare evaluation apparatus 1 according to the embodiment of the present invention performs the luminance adjustment process (fifth step of the present invention) so that the average luminance value of the imaged data matches a predetermined value. The glare of the display unit of the display device 7 may be evaluated by each step after step S13.

  In the above description, in step S24, the imaging device setting unit 12 is configured to change the exposure time set in the imaging device 3 based on the exposure time adjustment data stored in the storage unit 13. The time setting change is not limited to this configuration. For example, the imaging device setting unit 12 arbitrarily sets the exposure time of the imaging device 3 and instructs the luminance determination unit 11 to obtain the average luminance value at that time. In response to this instruction, the luminance determination unit 11 obtains a luminance average value. This operation is performed again by changing the exposure time setting. From the result obtained by performing the above operation, the imaging device setting unit 12 obtains a correspondence relationship between the brightness average value of the imaging data and the exposure time of the imaging device 3, and is set in the imaging device 3 based on the obtained correspondence relationship. The exposure time may be changed.

  Below, the Example which performed the glare evaluation using the above-mentioned glare evaluation apparatus 1 is described. An area camera with 5 million pixels was prepared as the imaging device 3.

Example 1
In Example 1, the glare evaluation when different types of anti-glare films were respectively attached to the display unit of the display device 7 was performed using the glare evaluation device 1 by performing the above-described glare evaluation method. In the first embodiment, the relative size between the imaging device 3 and the display unit of the display device 7 is set so that the shooting size per pixel of the imaging data is 0.75 times the size of one pixel of the display image. The glare was evaluated by adjusting the positional relationship.

  First, a display device A was prepared as the display device 7 to be evaluated. The display unit of the display device A is an organic EL display (“Galaxy (registered trademark) S3” manufactured by Samsung Electronics Co., Ltd.) having a resolution of 306 ppi. In addition, five types of samples α, β, γ, δ, and ε with different glare sensory evaluation results were prepared as antiglare films to be attached to the display unit of the display device A. The sensory evaluation is evaluated in five stages, and the higher the numerical value, the smaller the degree of glare. Sample α has a sensory evaluation result of 3.0, sample β has a sensory evaluation result of 3.5, sample γ has a sensory evaluation result of 4.0, sample δ has a sensory evaluation result of 4.5, sample ε has a sensory evaluation result Was 5.0. Therefore, in the sensory evaluation results, the sample ε is the antiglare film with the smallest glare.

  Next, the above-described five types of anti-glare films were respectively attached to the display unit of the display device A, and the above-described glitter evaluation method was performed using the glitter evaluation device 1. Then, for each of samples α, β, γ, δ, and ε attached to the display unit, the value of each standard deviation was obtained, and the value was used as the glare value. The correspondence between the standard deviation value and the sensory evaluation results is as shown in FIG. FIG. 10 is a bar graph showing the correspondence between the standard deviation value regarding the luminance distribution of the image displayed on the display unit equipped with the antiglare film and the samples with different sensory evaluation results in Example 1 of the present invention. is there. In FIG. 10, samples α, β, γ, δ, and ε with different sensory evaluations are shown on the horizontal axis, and standard deviation values (glare values) are shown on the vertical axis. As shown in FIG. 10, it can be seen that the magnitude relationship between the standard deviation values (glare values) corresponds to the quality of the sensory evaluation results.

(Example 2)
Next, as Example 2, glare evaluation was performed when an antiglare film was attached to the display portion of a different type of display device 7. Two types of display devices A and B were prepared as display devices 7 to be evaluated. Note that the glare evaluation for the display device A of Example 2 is that the imaging size of the imaging device 3 and the display device 7 is such that the imaging size per pixel of the imaging data is 0.76 times the size of one pixel of the display image. The relative positional relationship with the display unit was adjusted. On the other hand, the glare evaluation for the display device B of Example 2 is that the imaging size per pixel of the image data is 0.81 times the size of one pixel of the display image. The relative positional relationship with the display unit was adjusted.

  The display device A is the same as the display device used in the first embodiment. The display unit of the display device B is a liquid crystal display (“iPhone (registered trademark) 4S” manufactured by Apple Inc.) having a resolution of 326 ppi. Further, five types of samples α, β, γ, δ, and ε were prepared as anti-glare films to be mounted on the display portions of the display devices A and B, as in Example 1.

  First, the above-mentioned five types of anti-glare films are respectively attached to the display unit of the display device A, and the above-described glare evaluation method is performed using the glare evaluation device 1 to obtain respective standard deviation values (glare values). It was. Next, the above-mentioned five types of anti-glare films were mounted on the display device B, respectively, and the above-described glare evaluation method was performed using the glare evaluation device 1 to obtain the standard deviation values (glare values). The correspondence between the standard deviation value and the sensory evaluation results is as shown in FIG. FIG. 11 shows the correspondence between the standard deviation values relating to the luminance distribution of the images displayed on the two types of display units equipped with the antiglare film and the samples with different sensory evaluation results in Example 2 of the present invention. It is a bar graph to show. In FIG. 11, samples α, β, γ, δ, and ε having different sensory evaluations are shown on the horizontal axis, and standard deviation values (glare values) are shown on the vertical axis. As shown in FIG. 11, the magnitude relation of the standard deviation value (glare value) of the display device A corresponds to the quality of the sensory evaluation result. Moreover, it turns out that the magnitude relationship of the value (glare value) of the standard deviation of the display apparatus B and the quality of the sensory evaluation result correspond. Further, even when the same antiglare film is attached, the display device A and the display device B have different standard deviation values, and the display device B has a smaller standard deviation value than the display device A. I understand that That is, it can be seen that the display device B has less glare when the antiglare film is attached than the display device A.

(Example 3)
Next, using the glare evaluation apparatus 1 according to the embodiment of the present invention, as Example 3, glare evaluation was performed when an antiglare film was attached to the display device 7. In particular, the evaluation of glare is divided into the case where a double-sided tape containing silicon is used as a binder for attaching the anti-glare film to the display part and the case where the anti-glare film is directly placed on the display part without the double-sided tape. went. Examples of the double-sided tape include a first release film layer, a strong adhesive (optical adhesive sheet; OCA (Optically Clear Adhesive)) layer, a support substrate (polyethylene terephthalate), a silicon adhesive. A so-called AB tape composed of a layer and a second release film layer can be exemplified. For double-sided tapes, the first release film layer is peeled off and bonded to the non-concave surface of the antiglare film, and the second release film layer is peeled off and bonded to the display portion of the display device 7 to attach the antiglare film to the display portion. Can be made.

  For example, when an anti-glare film is purchased separately and attached to the display device 7 as a retrofit, it may be possible to attach the anti-glare film to the display device 7 via a double-sided tape. In this case, the distance between the antiglare film and the display unit is larger than when a double-sided tape is not sandwiched between the antiglare film and the display unit of the display device 7. Here, it is empirically known that the sensory evaluation is such that the greater the distance between the antiglare film and the display portion, the greater the degree of glare.

  Thus, in Example 3, the above-described glare evaluation method using the glare evaluation apparatus 1 according to the embodiment of the present invention provides a result correlated with the sensory evaluation regarding the difference in the glare degree that changes due to the presence or absence of the double-sided tape. I checked if it was possible.

  First, a display device C was prepared as the display device 7 to be evaluated. The display unit of the display device C is an organic EL display (“Galaxy S4” manufactured by Samsung Electronics Co., Ltd.) having a resolution of 441 ppi. In addition, five types of samples α, β, γ, δ, and ε having different glare sensory evaluation results similar to Example 1 were prepared as anti-glare films to be attached to the display unit of the display device C. Then, the above-described five types of anti-glare films were attached to the display unit of the display device C using double-sided tape, and the above-described glitter evaluation method was performed using the glitter evaluation apparatus 1. Note that the glare evaluation for the display device C of Example 3 is that the imaging device 3 and the display device 7 have a shooting size per pixel of the imaging data of 0.95 times the size of one pixel of the display image. The glare evaluation was performed by adjusting the relative positional relationship with the display unit.

  Next, each of the five types of anti-glare films described above was directly placed on the display unit of the display device C, and the above-described glitter evaluation method was performed using the glitter evaluation device 1. Then, the correspondence relationship between the obtained standard deviation value (glare value) and the sensory evaluation results is as shown in FIG. FIG. 12 shows the value of the standard deviation regarding the luminance distribution of the image displayed on the display unit when the antiglare film is attached via the double-sided tape and when the double-sided tape is not used in Example 3 of the present invention. And a bar graph showing a correspondence relationship between samples having different sensory evaluations. In FIG. 12, samples α, β, γ, δ, and ε having different sensory evaluations are shown on the horizontal axis, and standard deviation values (glare values) are shown on the vertical axis.

  As a result of performing the above-described glare evaluation method using the glare evaluation apparatus 1, as shown in FIG. 12, it is possible to evaluate the difference in the degree of glare between when the double-sided tape is used as a binder and when the double-sided tape is not used. I understood. In other words, as a result of the above-described glare evaluation method, the standard deviation value (glare value) is greater when a double-sided tape is used as a binder than when a double-sided tape is not used for any sample. The results correlated with the evaluation.

  The standard deviation values differ depending on whether the double-sided tape is used as a binder or not. In both cases, the standard corresponding to the sensory evaluation of each of the samples α, β, γ, δ, ε. A deviation value (glare value) was obtained.

  Therefore, the glare evaluation apparatus 1 according to the embodiment of the present invention can quantitatively indicate the sensory difference in the degree of glare between when the double-sided tape is used as the binder and when the double-sided tape is not used. In addition, a quantitative evaluation value corresponding to the sensory evaluation for each of the samples α, β, γ, δ, and ε can be obtained.

  From the foregoing description, many modifications and other embodiments of the present invention are obvious to one skilled in the art. Accordingly, the foregoing description should be construed as illustrative only and is provided for the purpose of teaching those skilled in the art the best mode of carrying out the invention. The details of the structure and / or function may be substantially changed without departing from the spirit of the invention.

  INDUSTRIAL APPLICABILITY The present invention can be widely used for evaluating glare that occurs when an antiglare film is attached to a display device that employs various types of display units such as a smartphone.

DESCRIPTION OF SYMBOLS 1 Glare evaluation apparatus 2 Case 3 Imaging device 3a Lens 4 Imaging device holding part 5 Imaging device stand 6 Display device stand 7 Display device 8 Main control part 10 Glitter measurement part 11 Brightness determination part 12 Imaging apparatus setting part 13 Storage part

Claims (6)

A glare evaluation device that evaluates glare in a display unit of a display device that has undergone antiglare processing,
An imaging device that captures a display image displayed on the display unit to obtain imaging data;
An adjustment unit that adjusts the shooting size of the display image captured per pixel of the image sensor of the imaging device;
The display that correlates with the magnitude of the glare as a glare value indicating the magnitude of the glare, based on imaging data obtained by capturing the display image with the imaging device in a state in which the shooting size is adjusted by the adjustment unit. A glare measuring unit for determining variations in luminance in the image,
The glare evaluation device that adjusts the image capturing data so that a captured size captured per pixel of the image sensor of the image capturing device is 0.7 times or more the size of one pixel of the display image in the image capturing data. .   The adjustment unit includes an imaging device holding unit that movably holds the imaging device so as to change a relative distance between the display unit and the imaging device, and the display unit and the imaging device. The glare evaluation apparatus according to claim 1, further comprising at least one of a display device pedestal that movably supports the display device so as to change a relative distance therebetween.   The glare evaluation apparatus according to claim 1, wherein the adjustment unit includes a zoom lens that can change a focal length of the imaging apparatus. An imaging device setting unit for setting an exposure time of the imaging device;
A luminance determination unit that obtains a luminance average value of imaging data captured by the imaging device in a state where the imaging size is adjusted by the adjustment unit, and determines whether the luminance average value matches a predetermined value; With
When the brightness determination unit determines that the average brightness value does not match a predetermined value, a correspondence relationship between the average brightness value of the imaging data and the exposure time is obtained, and the average brightness value of the imaging data is predetermined. The glare evaluation apparatus according to any one of claims 1 to 3, wherein the exposure time is set so as to coincide with a value. A glare evaluation method for evaluating glare in a display unit of a display device subjected to anti-glare processing,
In imaging data obtained by imaging a display image displayed on the display unit with an imaging device, a shooting size of the display image captured per pixel of an imaging element of the imaging device is one pixel of the display image. A first step of adjusting to be 0.7 times or more of the size of
A second step of setting a measurement area which is an area for evaluating glare on the display unit;
A third step of obtaining the image data by imaging the display image of the measurement area set in the second step by the imaging device in a state where the imaging size is adjusted in the first step;
A fourth step of obtaining a variation in luminance of the display image in the measurement area, which correlates with the magnitude of the glare, as a glare value indicating the magnitude of the glare from the imaging data obtained in the third step. Glare evaluation method.   After performing the second step and before performing the third step, a luminance average value is obtained from imaging data obtained by imaging the display image of the measurement area with the imaging device, and the luminance average The glare evaluation method according to claim 5, further comprising a fifth step of changing an exposure time setting of the imaging apparatus so as to match a predetermined value and adjusting a luminance average value of the imaging data. .