Sight sign prompt device

Abstract

To provide a target presentation device capable of easily changing a background color of a target to a desired hue.SOLUTION: A target presentation device 10 includes a target display part 12a for displaying a target for examining eye characteristics for an eye E to the examined, an operation part 15 for receiving designation of color information on a color of a background for displaying a target, and a control part 14 for setting the background color of the target on the basis of the color information received by the operation part 15.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a visual target presentation device. [Background technology]

[0002] There is known a visual target presenting device that presents visual targets for visual acuity testing to the subject's eye in order to test the visual function of the subject's eye. As such a visual target presenting device, conventionally, there have been devices that present visual targets printed on paper or a panel by illuminating them with a light source such as a tungsten lamp, a halogen lamp, a fluorescent lamp, or an LED, or devices that present the visual targets by projecting them onto a screen using a light source, but recently, devices that display the visual targets on an electronic display device such as a liquid crystal device illuminated by a backlight have been widely used (for example, see Patent Document 1).

[0003] Generally, these optotypes are displayed in black on a white background, but the background of optotypes using tungsten or halogen lamps as light sources has a low color temperature and appears reddish white. In contrast, the background of electronic display devices often has a high color temperature and appears bluish white. Also, fluorescent lights come in a variety of colors, from reddish incandescent light to bluish daylight light, and the color of the illuminated background varies. For this reason, when multiple types of optotype presentation devices with different light sources are used together, the color of the background varies from device to device, which may cause the subject to feel uncomfortable.

[0004] Patent Document 1 discloses that in order to suppress the variation in the brightness of the white background for each device, the amount of light of the backlight that illuminates the background of the display is controlled according to a predetermined adjustment value that is preset for each device, and the brightness of the background is switched. However, the variation in the color of the white background cannot be eliminated by only controlling the amount of light of the backlight. In addition, in the case of an electronic display device, the color can be changed by lowering the brightness of one of the RGB pixels, but simply lowering the brightness of the pixel makes the background dark, which affects the appearance and the results of a visual acuity test. In order to change the color without darkening the background, it is necessary to consider the balance of the three RGB colors, so it is not easy to reproduce the desired color. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2008-206675 A Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been made in consideration of the above-mentioned problems, and has an object to provide an optotype presentation device that can easily change the background color of an optotype to a desired color. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, the optotype presentation device of the present invention comprises an optotype display unit that presents an optotype for testing eye characteristics to a subject's eye, an input unit that accepts designation of color information relating to the color of the background on which the optotype is displayed, and a background color setting unit that sets the background color of the optotype based on the color information accepted by the input unit. Effect of the Invention

[0008] In the optotype presentation device configured in this manner, the background color of the optotype can be easily set to a desired color. [Brief description of the drawings]

[0009] [Figure 1] 1 is a schematic diagram showing an overall configuration of a visual target presentation device according to a first embodiment. [Diagram 2] 3 is a schematic diagram of a background and an optotype displayed in an image display area of ​​the optotype display unit. FIG. [Diagram 3] 1A and 1B are schematic diagrams of an operation unit, in which (1) shows a schematic diagram of the operation unit of a first embodiment, and (2) shows a schematic diagram of the operation unit of a modified example. [Figure 4] This is an explanatory diagram of a table in which color information is associated with the gradation of each RGB color pixel for each piece of color information, where (1) shows the table configuration of the conversion table and (2) shows the table configuration of the gradation value table. [Diagram 5] FIG. 11 is a schematic diagram showing a configuration of a visual target presentation device according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] (First embodiment) Hereinafter, a first embodiment of a visual target presenting device of the present invention will be described with reference to the drawings. First, the configuration of a visual target presenting device 10 according to the first embodiment will be described with reference to Figs.

[0011] The optotype presentation device 10 of the first embodiment is a device that displays an optotype for testing the ocular characteristics of the subject's eye E on a white background and presents it to the subject's eye E, and the color of this background (background color) can be set according to the specification of a user, such as an examiner.

[0012] Here, "setting background color" means setting (changing) the hue of the white background color to a desired hue according to the user's specification. "Hue" refers to the degree of color shading and deviation, and subtle shades. For example, "white" can look different depending on the mixture of light and colors, such as "reddish white" or "bluish white."

[0013] For this reason, in devices capable of presenting a visual target to the subject's eye E, such as a visual target presenting device or an eye examination device having a visual target presenting means, the white color of the visual target may differ for each model depending on the type of light source, such as a backlight, that illuminates the visual target, or the light, such as a fluorescent lamp, that illuminates the room, and when different models of visual target presenting devices are mixed, the subject may feel uncomfortable. To solve this problem, the visual target presenting device 10 according to the first embodiment is configured so that the background color can be set to a desired color.

[0014] As shown in FIG. 1, the visual target presentation device 10 according to the first embodiment includes a main body 1 having a housing 11, a visual target presentation optical system 12, a memory 13 as a storage unit, and a control unit 14 as a background color setting unit, an operation unit 15 as an input unit, and an eye examination table 16 on which the main body 1 is placed.

[0015] The main body 1 includes a housing 11 with a built-in target presenting optical system 12, a memory 13, a control unit 14, etc., and is placed on an eye examination table 16, etc. A window 11a is provided on the front surface (subject P side) of the housing 11 so that the subject P can visually recognize the target.

[0016] The target presenting optical system 12 includes a target display unit 12a, a first reflecting mirror 12b, a lens 12c, and a second reflecting mirror 12d.

[0017] In the first embodiment, the optotype display unit 12a is a liquid crystal display (LCD) device that displays a predetermined optotype on a white background illuminated by a backlight (light source). In addition to a liquid crystal display, the optotype display unit 12a may preferably be an organic electroluminescent display (OLED), but is not limited to these.

[0018] The optotype is not particularly limited as long as it is used in eye examination, and suitable examples include Landolt rings, Snellen optotypes, E charts, etc. In addition, the optotype can be various optotypes such as optotypes consisting of characters such as hiragana or katakana, pictures of animals or fingers, etc., specific figures for binocular vision function eye examination such as a cross optotype, or optotypes consisting of landscape paintings or landscape photographs, etc.

[0019] The target presenting optical system 12 reflects a light beam from the target display unit 12a toward the lens 12c by the first reflecting mirror 12b, and refracts the light by the lens 12c to form a virtual image i of the target at a distance from the subject's eye E. The light beam transmitted through the lens 12c is reflected by the second reflecting mirror 12d to present the target at a distance in front of the subject's eye E. The subject P visually recognizes the target through a window 11a provided in the housing 11.

[0020] 1, the optotype presenting device 10 may include an eye examination unit (refractor head) 17 for correcting the visual function of the subject's eye E between the window 11a and the subject's eye E. The eye examination unit 17 has a plurality of built-in optical members such as a polarizing filter, a spherical lens, a cylindrical lens, and a prism, and these optical members can be selectively arranged in eye examination windows provided corresponding to the left and right subjects' eyes E. The subject P can visually recognize the optotype through the window 11a with the visual function of the subject's eye E corrected by the eye examination unit 17.

[0021] The optotype display unit 12a, which is made up of an electronic display device, has a plurality of pixels including three colors, R (red), G (green), and B (blue), and has a gradation changing function capable of changing the gradation (gradation value) of each color pixel. The optotype display unit 12a can change the color of the optotype by changing the gradation of each color pixel under the control of the control unit 14. Note that the pixel colors are not limited to the three colors of RGB, and may be four or more colors.

[0022] The term "gradation" refers to the number of stages that indicate the density or brightness of a color in stages, and in the first embodiment, it is 8-bit 256 gradations (0 to 255), but is not limited to this. In the optotype display unit 12a, the initial value (default) of the gradation of the background 102 in the image display area 100 shown in FIG. 2 is set to an optimal luminance value (for example, 200 Cd / m 2 ), and the gradation of each R, G, and B pixel is set to the same value. For example, the gradation value is set to 98 gradations (R: 98, G: 98, B: 98) out of a maximum of 255 gradations. Then, based on the color information input from the operation unit 15, the control unit 14 calculates the gradation of each RGB pixel, and based on the calculated gradation, the optotype display unit 12a changes the gradation of each RGB pixel of the background 102. As a result, the background color is set to a desired white color.

[0023] On the other hand, the gradation of the target area 101 forming the target is set to 0 gradation (R:0, G:0, B:0) which is the darkest (lowest transmittance) state (black color), but by changing the gradation of the target area 101, it is possible to change the contrast of the target against the background 102. This makes it possible to perform a contrast test or the like for measuring the contrast sensitivity of the subject's eye E.

[0024] The memory 13 is composed of storage media such as RAM, ROM, semiconductor memory, a hard disk drive, etc. The memory 13 stores in advance programs and various information for the control unit 14 to execute processing, and also stores various information obtained by processing of the control unit 14. The memory 13 also stores a table in which, for each piece of color information relating to the background color, this color information is associated with the gradation of each RGB pixel.

[0025] FIG. 4 shows an example of a table used in this embodiment. (1) in FIG. 4 is an example of a conversion table T1, which is a table in which a correction value for converting the gradation of each pixel of color from an initial value (default) to a value corresponding to color information is set. As shown in this conversion table T1, in the first embodiment, color temperature is used as color information. In the conversion table T1, seven color temperatures are set in increments of 1000 K from 2000 K to 8000 K, and correction values ​​for the luminance value of each color of RGB are set for each color temperature. These correction values ​​are set in consideration of the balance of each pixel of RGB so that the apparent brightness (luminance) of the background 102 does not change even if the color temperature is changed to any of the seven levels.

[0026] That is, if only the color tone is to be changed, it can be achieved by changing the gradation values ​​of each of the R, G, and B pixels individually. For example, when making the background color reddish white, it is possible to simply lower the gradation values ​​of G and B, such as (R:98, G:98, B:98) as compared to the above-mentioned (R:98, G:98, B:98), but it is difficult to control the color tone along the approximate blackbody radiation locus, and the luminance of the background may decrease, which may affect the inspection result. For this reason, it is necessary to adjust each gradation value while considering the balance of RGB, and to change the color tone of the background along the approximate blackbody radiation locus without decreasing the apparent brightness (luminance). To achieve this, in this embodiment, the user or the like sets a correction value of the gradation value for each color of RGB.

[0027] FIG. 4 (2) shows the gradation values ​​obtained by multiplying the initial value (default) of gradation 98 by the correction values ​​of the pixels of each color of RGB obtained from the conversion table T1 in (1) for each color temperature. For example, when the color temperature is 2000K, the conversion table T1 selects R=2.595, G=0.675, and B=0.112 as correction values. By multiplying these correction values ​​by the initial values ​​of the gradation values ​​R=98, G=98, and B=98, the corrected gradation values ​​R=254, G=66, and B=11 are obtained. The initial values ​​(default) of the gradation values ​​of each pixel of RGB are set to values ​​adjusted to the optimal gradation among 256 gradations so that the electronic display device has an appropriate luminance, taking into account the individual differences of the electronic display device that is the optotype display unit 12a and the optotype presenting optical system 12. Also, if the initial value is determined, the result of the multiplication may be stored as a table, as shown in FIG. 4(2), and the gradation value corresponding to the set color temperature may be directly read out.

[0028] The correction values ​​of the conversion table T1 are not limited to the values ​​shown in FIG. 4, but may be set to values ​​based on the spectral characteristic values ​​according to the type of electronic display device, or values ​​based on the spectral characteristic values ​​of each individual electronic display device.

[0029] The color temperatures and correction values ​​of the pixels of each color in the conversion table T1 may be stored unalterably in the memory 13 at the time of manufacture or the like, or may be stored changeably by a user, a maintenance technician or the like via the operation unit 15 or the like. Furthermore, each value in the gradation value table T2 may also be stored unalterably in the memory 13, or may be stored changeably. If changeable, for example, when a user or the like changes the initial value of the gradation value, the control unit 14 may recalculate the luminance of the pixels of each color for each color temperature (or for the color temperature selected via the operation unit 15) based on the initial value after the change and the correction value of the conversion table, and store the recalculated luminance in the gradation value table T2.

[0030] The control unit 14 is composed of a microprocessor such as a CPU, etc. The control unit 14 controls the operation of the entire optotype presentation device 10 according to signals such as operation instructions from the operation unit 15, and also functions as a display control unit for the optotype on the optotype display unit 12a, a drive control unit for the drive mechanism of the first reflecting mirror 12b, a background color setting unit that sets (changes) the background color of the optotype display unit 12a, etc.

[0031] The control unit 14 as a background color setting unit acquires a color temperature from the operation unit 15, searches a table (gradation value table T2) stored in the memory 13 based on the acquired color temperature, and acquires a corrected gradation value of each pixel of RGB corresponding to the color temperature. Then, by controlling the optotype display unit 12a based on the acquired gradation value, the background 102 is displayed in the image display area 100 of the optotype display unit 12a in a background color adjusted to a color corresponding to the selected color temperature.

[0032] The operation unit 15 is a user interface operated by the examiner, who is the user, and has a function as an input unit for inputting information and operation instructions. In this embodiment, the operation unit 15 is a remote controller that the user can remotely operate from a location away from the optotype presentation device 10. The information and operation instructions input via the operation unit 15 are converted into signals and input to the control unit 14.

[0033] The operation unit 15 is not limited to a remote controller, and may include, instead of or in addition to a remote controller, buttons, keys, and control levers provided on the housing 11, and operation devices (mouse, keyboard, track pad, buttons, touch panel, etc.) of a personal computer or mobile terminal capable of communicating with the control unit 14. The operation unit 15 may also include a processor and a computer program for performing operations and inputs based on voice.

[0034] A schematic diagram of the operation unit 15 of this embodiment is shown in FIG. 3(1). As shown in this figure, the operation unit 15 has a display unit 15a on which input information and the like are displayed, various operation buttons 15b for inputting various information and operation instructions, a color selection button 15c for selecting a color temperature as color information, and a color display unit 15d on which the selected color temperature is displayed. The display unit 15a and the color display unit 15d are made of electronic display devices such as LEDs. The color selection button 15c has a button for increasing the color temperature and a button for decreasing the color temperature, and each time these buttons are pressed, the color temperature is switched to a higher or lower value and is displayed digitally on the color display unit 15d. A signal corresponding to the selected color temperature is input from the operation unit 15 to the control unit 14. This input may be performed automatically when a predetermined time (several seconds) has elapsed after the color temperature is selected, or may be performed when a decision button is provided separately from the color selection button 15c and the decision button is pressed.

[0035] The color display unit 15d is not limited to an electronic display device, and may be configured such that a member on which numbers are printed is mechanically switched according to the operation of the color selection button 15c. In addition, in this embodiment, the color temperature is configured to be selectable in increments of 1000K from 2000K to 8000K, but the present invention is not limited to this, and the color temperature may be selected with finer numerical values ​​such as 1K, 10K, 50K, 100K, and so on. In this case, the user or the like sets the values ​​of the conversion table T1 and the gradation value table T2 for each selectable color temperature. The color display unit 15d may be configured to be displayed on the display unit 15a, and the color selection button 15c may use a part of the various operation buttons 15b. In this case, the user or the like switches the mode selection, and the contents of the color display unit 15d are displayed on the display unit 15a, and the functions of some of the various operation buttons 15b function as the color selection button 15c.

[0036] The operation (example of use) of the optotype presentation device 10 according to the first embodiment configured as described above will be described below. In the optotype presentation device 10 according to the first embodiment, in order to set the background color of the background 102 on which the optotype is displayed to a desired color, the examiner first operates the color selection button 15c of the operation unit 15 to select the desired color temperature.

[0037] For example, since the optotype presentation device 10 of the present embodiment is equipped with the optotype display unit 12a made of an LCD or the like, LEDs or the like are used for the backlight, and the background color of the image display area 100 has a high color temperature and appears bluish-white. In contrast, an optotype presentation device that illuminates the optotype with a light source made of a tungsten lamp, a halogen lamp, or the like has a low color temperature of the light source, and therefore the background color appears reddish. Even if an electronic display device is used as the optotype display unit 12a, the hue of the background color may differ if the type is different, such as an LED or an OELD, or if the manufacturer or model is different even if the type is the same.

[0038] In the case of using multiple devices with different background colors in this way, it is desirable to match the background colors of the devices. For example, in order to match the background color of the optotype presentation device 10 of this embodiment to the background color of an optotype presentation device using a tungsten lamp or the like, the user operates the operation unit 15 to select a low color temperature of 2000K or 3000K.

[0039] The operation unit 15 generates a signal corresponding to the selected color temperature and outputs it to the control unit 14. The control unit 14, which receives this signal, searches the gradation value table T2 based on the selected color temperature and acquires the gradation value of each pixel of RGB corresponding to the color temperature. The control unit 14 controls the optotype display unit 12a based on the acquired gradation value, so that the background 102 is displayed in the image display area 100 of the optotype display unit 12a with the background color adjusted to a color corresponding to the selected color temperature. Therefore, in the first embodiment, it is possible to provide an optotype presenting device 10 that can easily change the background color of the optotype to a desired color. As a result, it is possible to unify the background colors of multiple optotype presenting devices to the same color or similar colors.

[0040] After completing the setting of the background color, the examiner operates the operation button 15b of the operation unit 15 to display a predetermined optotype on the optotype presenting device 10 and measure the ocular characteristics of the subject's eye E. The optotype presenting device 10, which receives this operation instruction signal, displays the background 102 in a preset background color in the image display area 100 of the optotype display unit 12a under the control of the control unit 14, and displays the optotype. This allows the subject P to measure the ocular characteristics of the subject's eye E. Since the background colors of the multiple optotype presenting devices are the same, the subject P does not feel uncomfortable even when the test is performed using multiple optotype presenting devices, and the subject P can take the test comfortably.

[0041] If the color information selected by the user and the luminance value of the corresponding pixel of each color are stored in the memory 13, from the next examination onwards, the control unit 14 can control the optotype display unit 12a based on the gradation value of the pixel of each color stored in the memory 13. Therefore, the examiner does not need to select the background color every time an examination is performed, and efficient measurement is possible.

[0042] In the first embodiment, the optotype display unit 12a is an electronic display device having a plurality of pixels including at least three colors of RGB, and capable of color display of optotypes by changing the gradation of each color pixel. The control unit 14, which has the function of a background color setting unit, calculates the gradation of each color pixel corresponding to the background based on the color information, and controls the electronic display device (optotype display unit 12a) based on the calculation result to change the gradation of the pixel, thereby setting the background color. This makes it possible to determine the gradation of each pixel while taking into consideration the balance of the luminance ratio of each color pixel such as RGB, and to set the background color to a desired hue without reducing the apparent brightness of the background.

[0043] In the first embodiment, a storage unit (memory 13) is provided in which a table (conversion table T1, gradation value table T2) is stored in which, for each piece of color information, the color information is associated with the gradation of pixels of each color. A background color setting unit (control unit 14) calculates the gradation of each color pixel corresponding to the background based on the color information received by the input unit (operation unit 15) and the gradation of each color pixel acquired from the table in the storage unit (memory 13). With this configuration, the gradation of each pixel can be determined more appropriately and quickly, and the background color can be set more appropriately and quickly.

[0044] In the first embodiment, the color information is the color temperature of the background color, and the input unit (operation unit 15) is configured to be able to select at least two or more color temperatures. With this configuration, the user can select the color tone of the background color of the optotype presenting device 10 according to the background color of another device or according to the user's preference. In particular, in the first embodiment, since the user can select from seven color temperatures, the number of options for the color tone of the background color is increased, the degree of freedom in setting the color tone of the background color is increased, and the background color can be set more appropriately according to the background color of another device or the user's preference. In addition, even if the color tone of the background color of another device changes due to device replacement or the like, the color tone of the background color of the optotype presenting device 10 can be appropriately changed according to the color tone.

[0045] As a modified example, the color information can be a color name. The color names (light source colors) of light from a light source or the like and the color temperatures corresponding to the color names are defined by the JIS standard (JIS Z 9112:2019) as shown in Table 1 below. For this reason, if the color information can be selected by color name from the operation unit 15, the hue of the background color can be set based on the color temperature corresponding to the color name.

[0046] [Table 1]

[0047] Fig. 3(2) shows a schematic diagram of the operation unit 15 of a modified example that allows selection by color name. As shown in Fig. 3(2), when the user operates the color selection button 15c, the color display unit 15d switches between color names such as "warm white" and displays them. Information on the selected color name is input from the operation unit 15 to the control unit 14 as a signal.

[0048] In the optotype presentation device 10, for example, a table in which color names are associated with optimal color temperatures (for example, the median of the color temperature range shown in Table 1) for each color name is stored in advance in the memory 13. Then, based on the color name input from the operation unit 15, the control unit 14 selects a color temperature from the table, and similarly to the first embodiment, obtains the luminance value of the pixel of each color from the conversion table T1 and the gradation value table T2, and controls the optotype display unit 12a based on the obtained luminance value to set the background color.

[0049] In this way, even if the color information is a color name, the hue of the background color can be set appropriately, and furthermore, compared to when selecting by color temperature, the user can easily imagine the background color by the color name, and can select the hue of the background color more appropriately. By allowing the user to select from at least two color names, and preferably five or more as shown in Table 1, the freedom of hue selection is improved, and the hue of the background color can be set more appropriately.

[0050] Second embodiment Next, the optotype presenting device 10 according to the second embodiment will be described with reference to Fig. 5. The optotype presenting device 10 according to the second embodiment shown in Fig. 5 has the same basic configuration as the optotype presenting device 10 according to the first embodiment shown in Fig. 1, etc., except that it further includes an eye examination unit 17 and a second optotype display unit 19 for near vision eye examination. Therefore, in the following, detailed descriptions of the configuration and operation similar to those of the first embodiment will be omitted, and configurations and operations different from those of the first embodiment will be mainly described.

[0051] The visual target presenting device 10 according to the second embodiment shown in FIG. 5 includes, within a housing 11, a main body 1 incorporating a visual target presenting optical system 12, a memory 13, and a control unit 14, an operation unit 15 as an input unit, an eye examination table 16 (see FIG. 1), an eye examination unit 17, a support unit 18 that supports the eye examination unit 17, and a second visual target display unit 19 for near vision eye examination.

[0052] The optometry unit 17 is provided with a near point rod 17b extending horizontally on the main body 1 side. A second optotype display unit 19 for near vision optometry is suspended at a position at a near vision optometry distance (for example, 300 to 400 mm from the subject's eye E) from the tip or midway of the near point rod 17b. The near point rod 17b is foldable, and when not in use, the near point rod 17b and the second optotype display unit 19 can be stored vertically.

[0053] The eye examination unit 17 further includes a light source 17a on the main body 1 side for illuminating the second optotype display unit 19. The light source 17a may be, for example, an LED capable of adjusting color.

[0054] The second optotype display unit 19 displays an optotype for near vision optometry. The second optotype display unit 19 uses a plate-like member or paper on which an optotype is printed, but an electronic display device such as an LCD can also be used. The second optotype display unit 19 can be moved forward and backward along the near point rod 17b, and the near vision optometry distance can be changed as desired. By performing near vision optometry using the second optotype display unit 19, it is possible to check for changes in the accommodation of the subject's eye E due to aging, etc.

[0055] The optotype presentation device 10 of the second embodiment can change the color of the light source 17a under the control of the control unit 14 based on color information (color temperature, color name) input from the operation unit 15, thereby making it possible to set the background color of the second optotype display unit 19 illuminated by the light source 17a to a desired color. As in the first embodiment, the background color of the optotype display unit 12a of the main body unit 1 can also be set to a desired color under the control of the control unit 14. That is, the color of the background color of either the optotype display unit 12a or the second optotype display unit 19 can be changed to match the color of the other background color, or the color of both background colors can be changed to match the color of the background color of the optotype presentation device other than these.

[0056] In order to set the color of the background color of the second optotype display unit 19, in the second embodiment, for example, a table in which color information and the emission color information of the light source 17a are associated with each other for each color information is stored in advance in the memory 13. Then, based on the color information input from the operation unit 15, the control unit 14 searches the table, acquires the corresponding emission color information, and causes the light source 17a to emit light based on the acquired emission color information. By irradiating light from the light source 17a whose emission color has been adjusted in this way, the background color of the second optotype display unit 19 can be set to the color information (color temperature, color temperature corresponding to the color name) set by the user. Note that, for example, chromaticity such as xy chromaticity can be used as the emission color information. For example, by using an xy chromaticity diagram, the chromaticity of x and y corresponding to the color temperature can be acquired based on the approximate blackbody radiation locus on the xy chromaticity diagram and the selected color temperature.

[0057] As described above, the optotype presenting device 10 of the second embodiment can obtain the same effects as those of the first embodiment. That is, the optotype presenting device 10 of the second embodiment includes an optotype display unit 12a and a second optotype display unit 19 that present optotypes for testing eye characteristics to the subject's eye E, an input unit (operation unit 15) that accepts designation of color information (e.g., color temperature, color name) related to the color of the background on which the optotypes are displayed, and a background color setting unit (control unit 14) that sets the background color of the optotype based on the color information accepted by the input unit. Therefore, the background color of the optotype of the optotype display unit 12a and / or the second optotype display unit 19 can be easily set to a desired color.

[0058] Furthermore, in the second embodiment, the optotype display unit (second optotype display unit 19) includes a light source 17a that illuminates the background. The background color setting unit (control unit 14) controls the light source 17a based on color information received by the input unit (operation unit 15) to change the chromaticity of the light source 17a to set the background color, and therefore the background color of the optotype illuminated by the light from the light source 17a can be set to a desired color.

[0059] Incidentally, the optotype presenting device 10 of the second embodiment includes two optotype display units, an optotype display unit 12a made of an electronic display device provided in the main body unit 1, and a second optotype display unit 19 for near vision examination, and the background color of these optotypes can be set to a desired color, but is not limited to this configuration. For example, the optotype presenting device may include only the second optotype display unit 19 for near vision examination, or may include the second optotype display unit 19 and a paper optotype display unit arranged at a distance for far vision examination (for example, 5 m), or an optotype display unit that projects optotypes onto a screen. The configuration may be such that the background color on which the optotypes are displayed can be changed to a desired color by adjusting the emission color of the light source that illuminates these optotype display units.

[0060] The visual target presentation device 10 of the present invention has been described above based on the embodiments. However, the specific configuration is not limited to these embodiments, and design changes and additions are permitted as long as they do not deviate from the gist of the invention according to each claim in the claims.

[0061] For example, in the optotype presentation device 10 of each of the above-mentioned embodiments, the conversion table T1 and the gradation value table T2 are stored in the memory 13. If these tables are prepared by measuring the spectral characteristic values ​​of the electronic display device and the light source installed in each optotype presentation device 10 during the manufacture of the optotype presentation device 10, calculating appropriate correction values ​​and initial values ​​corresponding to the obtained spectral characteristic values, and setting the tables, the color tone of the background color can be reproduced with higher accuracy.

[0062] In addition, in each of the above embodiments, the conversion table T1 and the gradation value table T2 are used as tables in which color information and the gradation of each color pixel of RGB are associated with each other, but the present invention is not limited to this. For example, only the gradation value table T2 may be used. Also, without using such tables, the control unit 14 may calculate the gradation of each color pixel using a predetermined formula based on color information such as color temperature and the type and optical characteristic values ​​of the optotype display unit 12a and the light source 17a. [Explanation of symbols]

[0063] 10 Visual target presentation device 12a Visual target display section 13 Memory (storage section) 14 Control section (background color setting section) 15 Operation section (input section) 17a light source 102 Background E. Examined eye

Claims

1. an optotype display unit that presents an optotype for testing eye characteristics to a subject's eye; an input unit for receiving designation of color information regarding the color of a background on which the optotype is displayed; a background color setting unit that sets a white color, which is a background color of the optotype, based on the color information received by the input unit; A storage unit, The optotype display unit includes an electronic display device having a plurality of pixels including at least three colors of RGB, and capable of displaying the optotype in color by changing the gradation of the pixels of each color; the storage unit stores a table in which, for each of the color information, the color information, an initial value of a gradation of the pixel of each color, and a correction value for converting the gradation of the pixel of each color from the initial value to a value corresponding to the color information, the correction value being set based on a spectral characteristic of the electronic display device; the background color setting unit obtains a correction value corresponding to the spectral characteristics of the electronic display device from the table in the memory unit based on the color information received by the input unit, calculates a gradation of the pixel of each color corresponding to the background based on the obtained correction value and the initial value, and controls the electronic display device based on the calculation result to change the gradation of the pixel, thereby setting the white color of the background color.

2. The visual target presentation device as described in claim 1, characterized in that the correction value of the gradation of each pixel is set in advance so as to control the color tone approximately along a blackbody radiation locus.

3. The optotype display unit includes a light source that illuminates the background, 3. The visual target presentation device according to claim 1, wherein the background color setting unit sets the background color by controlling the light source to change the chromaticity of the light source based on the color information.

4. The visual target presentation device according to any one of claims 1 to 3, characterized in that the color information is either a color temperature of the background color or a color name corresponding to the color temperature, and the input unit is configured to be able to select at least two or more of the color temperatures and at least two or more of the color names.

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