Refraction characteristics measuring device

Abstract

To provide a refractive inspection device for measuring refractive characteristics by making first light and second light enter an eye through two openings, capable of improving accuracy of inspection and efficiency.SOLUTION: There is provided a refractive characteristic measuring device (1) for measuring refractive characteristics of an eye (25), comprising: a light emission part (20); an opening member (10) having a first opening (11) and a second opening (12) which are provided between the eye and the light emission part, and through which light which is emitted by the light emission part passes after narrowing the light; a first optical element (13) for transmitting light in a first wavelength band and provided on the first opening; a second optical element (14) for transmitting the light in a second wavelength band and provided on the second opening. The light emission part has: a background part (23) emitting white light; a first target part (21) for emitting first light (L1) whose color is a complementary color to the color of the light in the first wavelength band; and a second target part (22) for emitting second light (L2) whose color is a complementary color to the color of the light in the second wavelength band.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a refractive characteristic measuring device for measuring the refractive characteristics of an eye. [Background technology]

[0002] When prescribing glasses or contact lenses, a refraction test is performed to measure the refractive characteristics of the eye. There are two types of refraction test: a subjective test in which the examinee identifies how a presented target or light appears, and an objective test in which a light beam is projected onto the eyeball and observed from the outside.

[0003] Patent Document 1 proposes a device and method for easily performing a subjective eye refraction test. This device and method utilize Scheiner's principle, in which a measuring disk placed in front of the eye is provided with two apertures through which light passes, and the refraction characteristics of the eye are measured based on the appearance of the first and second light beams that pass through the two apertures and reach the retina (the positional relationship between the two images). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-103743 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the refraction examination device and refraction examination method of Patent Document 1, the two openings are given different transmission characteristics, and the first light and the second light are set to pass through only one of the corresponding openings. In order to perform an accurate examination, it is necessary to set the position and orientation of the eye relative to the measurement disk so that the first light and the second light that have passed through each opening enter the pupil at the appropriate position and reach the retina. This setting is performed based on how the visual field areas corresponding to the two openings look, so in order to achieve accurate setting, it is important that the visual field areas are easily visible to the subject.

[0006] Furthermore, to test the refractive characteristics of the eye with high accuracy, it is necessary for the subject to be able to easily distinguish the positional relationship between the image created by the first light and the image created by the second light.

[0007] In order to meet the above requirements, the present invention aims to improve the accuracy and efficiency of testing in a refraction testing device that measures refractive characteristics by introducing a first light and a second light into an eye through two openings. [Means for solving the problem]

[0008] One aspect of the present invention is a refractive characteristic measuring device for measuring the refractive characteristics of an eye, comprising: a light emitting unit; an aperture member located between the light emitting unit and the eye, the aperture member having a first aperture and a second aperture for narrowing and passing light emitted by the light emitting unit; a first optical element provided at the first aperture, transmitting light of a first wavelength band and blocking the transmission of light of a second wavelength band; and a second optical element provided at the second aperture, transmitting light of the second wavelength band and blocking the transmission of light of the first wavelength band, wherein the light emitting unit comprises a background unit that emits white light, a first visual target unit that emits first light that is a complementary color to the light of the first wavelength band, and a second visual target unit that emits second light that is a complementary color to the light of the second wavelength band.

[0009] It is preferable that the light of the first wavelength band is green light, the light of the second wavelength band is red light, the first light emitted by the first visual target portion is magenta light, and the second light emitted by the second visual target portion is cyan light.

[0010] As an example, it is preferable that the background portion emits the white light by combining a blue component light having a maximum intensity in the wavelength band of 440 nm to 475 nm, a green component light having a maximum intensity in the wavelength band of 520 nm to 550 nm, and a red component light having a maximum intensity in the wavelength band of 600 nm to 650 nm, the first visual target portion emits the first light by combining the blue component light and the red component light, and the second visual target portion emits the second light by combining the blue component light and the green component light.

[0011] It is preferable that the first optical element satisfies the following conditions (1) and (2). (1)T B1 / T G1 <1 / 10 (2)T R1 / T G1 <1 / 10 T G1 : The transmittance of the first optical element at a wavelength corresponding to the maximum intensity of the green component of the second light. T B1 : The transmittance of the first optical element at a wavelength corresponding to the maximum intensity of the blue component of the first light. T R1 : The transmittance of the first optical element at a wavelength corresponding to the maximum intensity of the red component of the first light.

[0012] It is preferable that the second optical element satisfy the following conditions (3) and (4). (3) T B2 / T R2 <1 / 10 (4) T G2 / T R2 <1 / 10 T R2 : The transmittance of the second optical element at a wavelength corresponding to the maximum intensity of the red component of the first light. T B2 : The transmittance of the second optical element at a wavelength corresponding to the maximum intensity of the blue component of the second light. T G2 : The transmittance of the second optical element at a wavelength corresponding to the maximum intensity of the green component of the second light.

[0013] It is preferable that the first opening and the second opening are circular and have the same diameter, and that a first optotype image having a shape corresponding to the first optotype portion and a second optotype image having a shape corresponding to the second optotype portion are observed in an overlapping area where a first visual field area observed through the first opening and a second visual field area observed through the second opening overlap. Effect of the Invention

[0014] According to the present invention, in a refraction examination device that measures refractive characteristics by allowing a first light and a second light to enter an eye through two openings, the visual field area and image observed by the subject become easier to see, improving the accuracy and efficiency of the examination. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of a refraction characteristic measuring device. [Diagram 2] FIG. 2 is a diagram showing the position of the eye relative to a refractive characteristic measuring device. [Diagram 3] 1 is a diagram showing the visual field area and target image observed by a subject during an examination using a refraction characteristic measuring device. [Figure 4] 4A to 4C are diagrams showing examples of how a first target image and a second target image appear depending on the refractive characteristics of the eye. [Diagram 5] 1 is a diagram showing the visual field area and optotype image observed by a subject during an examination using a refraction characteristic measuring device of a comparative example. [Figure 6] 1 is a graph showing the relative luminosity of visible light. [Figure 7] 6 is a diagram showing the visual field area and the visual target image observed by the subject when the background part of the light emitting device is changed to white from the comparative example of FIG. 5. [Figure 8] 2 is a diagram showing the appearance of the first visual field area and the second visual field area observed by a subject in the refraction characteristics measuring device of the present embodiment. FIG. [Figure 9] 2 is a diagram showing the visual field area and optotype image observed by a subject during an examination using the refraction characteristic measuring device of the present embodiment. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] An outline of eye refraction testing (measurement of refraction characteristics) using the refraction characteristics measuring device 1 will be described with reference to Figures 1 to 4. This measurement of refraction characteristics utilizes Scheiner's principle, in which light passing through two different apertures is refracted by a lens, intersects at the focal position and becomes one, and separates into two at a position away from the focal position.

[0017] The refraction characteristic measuring device 1 has a measurement disk (aperture member) 10 and a light emitting device (light emitting section) 20, and the measurement disk 10 is placed between the light emitting device 20 and the subject's eye 25 (FIG. 2).

[0018] The measurement disk 10 is flat and has a first opening 11 and a second opening 12. The first opening 11 and the second opening 12 are circular openings that function as pinholes that narrow the light emitted by the light emitting device 20 and allow it to pass through. The first opening 11 and the second opening 12 have the same size (diameter). The sizes and center-to-center distances of the first opening 11 and the second opening 12 are set to such an extent that Scheiner's principle is expressed. The direction in which the first opening 11 and the second opening 12 are lined up (the direction connecting the centers of the first opening 11 and the second opening 12) is defined as the opening arrangement direction.

[0019] The light emitting device 20 has a flat emission surface parallel to the measurement disc 10, and emits a first light L1 and a second light L2 from the emission surface toward the measurement disc 10 at the same distance. The light emitting device 20 has two rectangular optotypes, a first optotype section 21 and a second optotype section 22, on the emission surface, and the first light L1 is emitted from the first optotype section 21, and the second light L2 is emitted from the second optotype section 22. Although details will be described later, the first light L1 and the second light L2 have different colors. The emission surface of the light emitting device 20 has a background section 23 other than the first optotype section 21 and the second optotype section 22, and light can be emitted from the background section 23 as well.

[0020] In the light emitting device 20, it is possible to change the relative positions of the first optotype portion 21 and the second optotype portion 22 along the direction of the arrangement of the openings of the measurement disk 10. In addition, it is possible to change the angular positions of the first optotype portion 21 and the second optotype portion 22 around an axis perpendicular to the emission surface (an axis passing through the boundary between the first optotype portion 21 and the second optotype portion 22). On a background portion 23 around the first optotype portion 21 and the second optotype portion 22, radial directional indicators 24 are formed to serve as a guide for the angular positions.

[0021] Various forms of light distribution by the light emitting device 20 can be selected. For example, a transmissive surface light source (display) that emits light in different colors in the first optotype portion 21, the second optotype portion 22, and the background portion 23 can be used. Alternatively, the first optotype portion 21, the second optotype portion 22, and the background portion 23 can be light reflecting portions, and light reflected by the first optotype portion 21, the second optotype portion 22, and the background portion 23 can be distributed.

[0022] The first opening 11 is provided with a first optical element 13, and the second opening 12 is provided with a second optical element 14. Although details will be described later, the first optical element 13 and the second optical element 14 each have selective transmittance (spectral characteristics) that transmit only light of different colors (wavelength bands). The first optical element 13 transmits light of a first wavelength band and blocks the transmission of light of a second wavelength band. The second optical element 14 transmits light of a second wavelength band and blocks the transmission of light of the first wavelength band. By utilizing this selective transmittance, a shape corresponding to the first visual target portion 21 is identified through the first opening 11, and a shape corresponding to the second visual target portion 22 is identified through the second opening 12.

[0023] 2, the measurement disk 10 is disposed between the light emitting device 20 and the subject's eye 25 so that the visual axis Q (an imaginary axis line passing through the center of the pupil 26) of the subject's eye 25 passes through the middle between the first opening 11 and the second opening 12. With this arrangement, the first light L1 passing through the first opening 11 and the second light L2 passing through the second opening 12 enter the pupil 26 of the subject's eye 25 and reach the retina 27.

[0024] Fig. 3 shows the visual field and image observed by the subject when the first light L1 is distributed from the first target portion 21 and the second light L2 is distributed from the second target portion 22 under the above-mentioned configuration and conditions. Note that in the embodiments and comparative examples of the present invention described below, the visual field and images are each colored, but here we will omit mentioning the differences in color and will explain the outline of the measurement of the refractive characteristics of the eye, assuming that the subject can distinguish between the visual field and the image.

[0025] 3, a substantially circular first visual field area 30 observed through the first opening 11 and a substantially circular second visual field area 31 observed through the second opening 12 overlap at a central overlap area 32. A portion corresponding to the first visual target portion 21 appears as a first visual target image 33, and a portion corresponding to the second visual target portion 22 appears as a second visual target image 34.

[0026] When the subject's eye 25 is in a proper position relative to the measurement disk 10 and the light emitting device 20, the first optotype image 33 and the second optotype image 34 are seen positioned on the overlapping region 32 as shown in FIG.

[0027] When the refractive characteristic of the eye 25 is appropriate, the position where the first light L1 that has passed through the first opening 11 reaches the retina 27 and the position where the second light L2 that has passed through the second opening 12 reaches the retina 27 coincide with the position in the opening arrangement direction of the first opening 11 and the second opening 12. In this case, the subject sees the first optotype image 33 and the second optotype image 34 overlapping in the opening arrangement direction. That is, when the first optotype portion 21 and the second optotype portion 22, each of which is rectangular, are arranged in a straight line on the light emitting device 20 side, the first optotype image 33 and the second optotype image 34, each of which is rectangular, are seen arranged in a straight line as shown in FIG. 4(A).

[0028] On the other hand, when the refractive power of the eye 25 is large relative to the appropriate refractive power of the eye, the first light L1 passing through the first opening 11 and the second light L2 passing through the second opening 12 cross each other before reaching the retina 27. Conversely, when the refractive power of the eye 25 is small relative to the appropriate refractive power of the eye, the first light L1 passing through the first opening 11 and the second light L2 passing through the second opening 12 do not cross each other on the retina 27 and do not cross each other before reaching the retina 27, and reach the retina 27 (the position where the first light L1 and the second light L2 cross each other is behind the retina 27). Therefore, in these cases, the subject sees the first target image 33 and the second target image 34 shifted in the aperture arrangement direction. In other words, when the rectangular first and second optotype portions 21 and 22 are aligned in a straight line on the light emitting device 20 side, the rectangular first and second optotype images 33 and 34 do not appear to be aligned in a straight line. Fig. 4(B) shows an example of how things look when the refractive power of the eye 25 is greater than appropriate, and Fig. 4(C) shows an example of how things look when the refractive power of the eye 25 is less than appropriate.

[0029] Based on the appearance of the first and second target images 33 and 34, information on the refractive characteristics of the eye 25 can be obtained. However, it is difficult for the subject to quantitatively identify the deviation between the two images and derive the refractive characteristics. Therefore, the light emitting device 20 changes the positional relationship between the first and second target images 21 and 22 along the aperture arrangement direction to create a matching state in which the first and second target images 33 and 34 appear to overlap in the aperture arrangement direction (the first and second target images 33 and 34 appear to be aligned in a straight line), and calculates the refractive power of the eye 25 from the positional relationship (amount of deviation and direction of deviation) between the first and second target images 21 and 22 in the matching state.

[0030] The processing unit 2 constituting the refractive characteristic measuring device 1 is composed of a computer or the like, and controls the change in position of the first visual target unit 21 and the second visual target unit 22 along the aperture arrangement direction. For example, the positions of the first visual target unit 21 and the second visual target unit 22 are changed according to the input operation of the subject or the measurer to an input device such as a keyboard or a touch panel. The processing unit 2 also acquires distance information between the emission surface of the light emitting device 20 and the measurement disk 10 from a distance sensor or the like. The processing unit 2 then calculates the refractive power of the eye 25 based on the positional deviation amount of the first visual target unit 21 and the second visual target unit 22 along the aperture arrangement direction when the first visual target image 33 and the second visual target image 34 are in the above-mentioned matching state on the retina 27. The refractive power of the eye 25 can be calculated using the formula described in the above-mentioned Patent Document 1 (JP Patent Publication No. 2020-103743).

[0031] According to the above-described refraction characteristics measuring device 1, the refractive power of the eye 25 can be measured with high accuracy simply by having the subject recognize the matching state of the first optotype image 33 and the second optotype image 34. Since there is no need for complex light emission control in the light emitting device 20 or for the subject or the measurer to memorize the amount of deviation between the first optotype image 33 and the second optotype image 34, the structure and control of the refraction characteristics measuring device 1 can be simplified and the effort required for measurement is reduced.

[0032] Since the refractive characteristics of the eye are azimuth-dependent, in an actual refraction test, it is necessary to measure the refractive characteristics described above in a plurality of azimuths. Specifically, it is desirable to set the aperture arrangement direction of the first aperture 11 and the second aperture 12 to three or more directions, namely, the horizontal direction, the vertical direction, and an intermediate direction between the horizontal direction and the vertical direction, and to perform measurements in each of them.

[0033] In the refraction characteristic measuring device 1, the first opening 11 and the second opening 12 are given selective light transmission, so that only a shape corresponding to the first optotype portion 21 is observed through the first opening 11, and only a shape corresponding to the second optotype portion 22 is observed through the second opening 12. As a result, only two images, the first optotype image 33 and the second optotype image 34, are simultaneously projected onto the retina 27, making it easier for the subject to accurately determine whether or not there is a positional misalignment between the first optotype image 33 and the second optotype image 34.

[0034] In order to provide the first opening 11 and the second opening 12 with such light selective transmittance, the first opening 11 is provided with a first optical element 13, and the second opening 12 is provided with a second optical element 14. The first optical element 13 and the second optical element 14 are optical filters that transmit light of different wavelength bands within the visible light wavelength range.

[0035] Incidentally, in the refraction characteristic measuring device 1 for subjective testing, the accuracy and efficiency of the test can be improved by making it easier for the subject to distinguish the first visual field area 30, the second visual field area 31, the overlapping area 32, the first optotype image 33, and the second optotype image 34 shown in Fig. 3. The present invention was made based on the discovery that the visibility during observation by the subject is significantly improved by establishing a predetermined relationship between the color of light emitted by each part of the light emitting device 20 and the spectral characteristics at the first opening 11 (first optical element 13) and the second opening 12 (second optical element 14) of the measurement disk 10, and the details thereof will be described below.

[0036] Note that Figures 5, 7, and 9 show cases where the two target images are aligned in the aperture arrangement direction, but this is just one example, and depending on the refractive characteristics of eye 25, the two target images may appear misaligned in the aperture arrangement direction, as shown in Figures 4(B) and 4(C).

[0037] First, a comparative example in which conditions are set differently from the present invention will be described. For example, in conventional subjective eye tests, there are known ones that use green or red observation targets, and following this, the first light L1 emitted from the first target section 21 of the light emitting device 20 is green light, and the second light L2 emitted from the second target section 22 is red light. The background section 23 of the light emitting device 20 is black. That is, in the comparative example, the light emitting device 20 includes the first target section 21 that emits green light, the second target section 22 that emits red light, and the black background section 23 (see the "Comparative Example" section in FIG. 1).

[0038] An optical filter that transmits green light and blocks red light is used as the first optical element 13. An optical filter that transmits red light and blocks green light is used as the second optical element 14. That is, in the comparative example, the wavelength band of light transmitted by the first optical element 13 is approximately the same as the wavelength band of the first light L1 (green light) emitted from the first visual target portion 21, and the wavelength band of light transmitted by the second optical element 14 is approximately the same as the wavelength band of the second light L2 (red light) emitted from the second visual target portion 22.

[0039] By the action of the first optical element 13 and the second optical element 14, the first light L1 which is green light passes only through the first opening 11 to reach the retina 27 of the eye 25, and the second light L2 which is red light passes only through the second opening 12 to reach the retina 27 of the eye 25. Since the background portion 23 is black, only the information of the first visual target portion 21 passes through the first opening 11, and only the information of the second visual target portion 22 passes through the second opening 12.

[0040] The visual field and the image seen by the subject in this case will be described with reference to Fig. 5. The first visual field 30GD, which is substantially circular and corresponds to the first aperture 11, is obtained by observing the black background 23 through the first optical element 13 that transmits green light, and appears dark green (low-luminance green) due to the influence of ambient light. The second visual field 31RD, which is substantially circular and corresponds to the second aperture 12, is obtained by observing the black background 23 through the second optical element 14 that transmits red light, and appears dark red (low-luminance red) due to the influence of ambient light. The overlapping region 32YD appears dark yellow (low-luminance yellow) due to the synthesis (additive color mixing) of the dark green of the first visual field 30GD and the dark red of the second visual field 31RD.

[0041] The green light emitted by the first target portion 21 is prevented from passing through the second opening 12 by the second optical element 14, passes only through the first opening 11 equipped with the first optical element 13, and appears as a green first target image 33G on the overlapping region 32. The red light emitted by the second target portion 22 is prevented from passing through the first opening 11 by the first optical element 13, passes only through the second opening 12 equipped with the second optical element 14, and appears as a red second target image 34R on the overlapping region 32.

[0042] When the subject's eye 25 is in the correct position relative to the measurement disk 10 and the light emission device 20, the first visual field area 30GD and the second visual field area 31RD appear to overlap evenly with each other, and the first visual target image 33G and the second visual target image 34R are located on the overlapping area 32YD, as shown in Figure 5.

[0043] During a refraction test, the position and orientation of the subject's face must be set so that the subject can see properly as described above. However, if the first field of view 30GD and the second field of view 31RD are dark green and dark red, respectively, against the black background of the background portion 23, the fields of view are dark and difficult for the subject to distinguish.

[0044] The relative luminosity of visible light is shown in Fig. 6. As can be seen from the graph in Fig. 6, red light (for example, light in a wavelength band around 610nm to 640nm) has a lower relative luminosity than green light (for example, light in a wavelength band around 530nm to 540nm). Therefore, of the dark green first visual field region 30GD and the dark red second visual field region 31RD in Fig. 5, the subject tends to have a hard time seeing the second visual field region 30RD in particular.

[0045] In addition, as long as the condition that two optotype images are observed separately by the light passing through the first opening 11 and the light passing through the second opening 12 is satisfied, it is possible to perform a refraction test even if the two lights incident on the subject's eye are not green light and red light. For example, it is also possible for the first optotype unit 21 to emit blue light (for example, light in a wavelength band around 450 nm to 465 nm) and for the first optical element 13 to use an optical filter that transmits blue light. However, as can be seen from FIG. 6, blue light has a lower relative luminosity factor than green light, and has the same problem as red light in that the visual field area seen through the first opening 11 is easily difficult to see.

[0046] Here, the inventor of the present invention has noticed that by emitting white light from the background portion 23 of the light emitting device 20 instead of making the background portion 23 black, the brightness of the visual field areas corresponding to the first opening 11 and the second opening 12 is increased, making them easier to distinguish. With reference to Fig. 7, a description will be given of how the visual field areas and images are seen by the subject when the background portion 23 is changed to emit white light in comparison to the above-mentioned comparative example.

[0047] The first field of view region 30GL, which is substantially circular and corresponds to the first opening 11, appears bright green (high brightness green) due to the green component of the white light when the white light emitted from the background portion 23 is observed through the first optical element 13 that transmits green light. The second field of view region 31RL, which is substantially circular and corresponds to the second opening 12, appears bright red (high brightness red) when the white light emitted from the background portion 23 is observed through the second optical element 14 that transmits red light. The overlapping region 32YL appears bright yellow (high brightness yellow) due to the synthesis (additive color mixing) of the bright green of the first field of view region 30GL and the bright red of the second field of view region 31RL. Therefore, the subject can easily distinguish the first field of view region 30GL, the second field of view region 31RL, and the overlapping region 32YL, compared to when the background portion 23 is black (FIG. 5).

[0048] However, in the light emitting device 20, when the first target unit 21 that emits green light and the second target unit 22 that emits red light are arranged on the background unit 23 that emits white light, the following problem occurs.

[0049] Not only the first light L1 (green light) emitted from the first target portion 21 but also components of a predetermined wavelength band near green in the white light emitted from the background portion 23 are transmitted through the first opening 11 equipped with the first optical element 13. Then, due to a refractive error between the light from the first target portion 21 and the light from the background portion 23, the corresponding portion of the first target portion 21 may not be a single color of green, but may appear as a first target image 33X that is a double image in which different color portions are mixed.

[0050] Not only the second light L2 (red light) emitted from the second optotype portion 22 but also components of a predetermined wavelength band near red in the white light emitted from the background portion 23 are transmitted through the second opening 12 equipped with the second optical element 14. Then, due to a refractive error between the light from the second optotype portion 22 and the light from the background portion 23, the corresponding portion of the second optotype portion 22 may not be monochromatic red, but may appear as a second optotype image 34X that is a double image in which portions of different colors are mixed.

[0051] There is a problem that the first optotype image 33X and the second optotype image 34X, which are seen as double images, make it difficult for the subject to grasp the positional relationship in the aperture arrangement direction. In this way, while maintaining the relationship in which the first optotype portion 21 and the second optotype portion 22 emit light of the same color as the light of the color transmitted by the first optical element 13 and the second optical element 14, only by making a change such that the background portion 23 emits white light, the visual field regions (30GL, 31RL) corresponding to the first aperture 11 and the second aperture 12 become easier to see, but there is a risk that it becomes difficult to distinguish the positional relationship between the first optotype image 33X and the second optotype image 34X corresponding to the first optotype portion 21 and the second optotype portion 22, respectively.

[0052] As a result of research, the inventors of the present invention have found that the above problem can be solved by making the colors of light emitted from the first visual target portion 21 and the second visual target portion 22 in the light emitting device 20 complementary to the color of light in the first wavelength band transmitted by the first optical element 13 and the color of light in the second wavelength band transmitted by the second optical element 14.

[0053] As a specific example, the first light L1 emitted by the first target unit 21 is magenta light, which is a complementary color of the green light (light of the first wavelength band) transmitted by the first optical element 13. In other words, the magenta color of the first light L1 is a color obtained by subtracting the green light (first wavelength band) component from white light.

[0054] The second light L2 emitted by the second target portion 22 is cyan light, which is a complementary color of the red light (light of the second wavelength band) transmitted by the second optical element 14. In other words, the cyan color of the second light L2 is a color obtained by subtracting the red light (second wavelength band) component from white light.

[0055] In other words, in the refraction characteristic measuring device 1 of an embodiment to which the present invention is applied, the light emitting device 20 includes a first target section 21 that emits magenta light as the first light L1, a second target section 22 that emits cyan light as the second light L2, and a background section 23 that emits white light (see the section marked "This embodiment" in Figure 1).

[0056] 8(A) shows the appearance of the first visual field region 30GG corresponding to the first aperture 11 when the background portion 23 emits white light, the first visual target portion 21 emits magenta first light L1, and the first optical element 13 is an optical filter that transmits only the wavelength band of green light. When observing only the visual field of the first aperture 11 by blocking the second aperture 12, for example, the appearance is as shown in FIG. 8(A).

[0057] In Fig. 8(A), the entire first visual field 30GG appears bright green (high brightness green) due to the green component of the white light when the background 23 emitting white light is observed through the first optical element 13, similarly to the first visual field 30GL of Fig. 7 described above. Since magenta is a color obtained by removing the green component from white (a complementary color to green), when the first visual target portion 21 emits the first light L1 of magenta, the figure presented by the first visual target portion 21 becomes a shadow (black due to subtraction of complementary colors) against the transmitted color (green) of the first optical element 13. As a result, the area of ​​the first visual field 30GG corresponding to the first visual target portion 21 becomes a first shadow portion 35 in which the shape of the first visual target portion 21 is not colored.

[0058] 8(B) shows the appearance of the second visual field region 31RR corresponding to the second opening 12 when the background portion 23 emits white light, the second visual target portion 22 emits cyan second light L2, and the second optical element 14 is an optical filter that transmits only the wavelength band of red light. When observing only the visual field of the second opening 12 by blocking the first opening 11, it appears as shown in FIG. 8(B).

[0059] In Fig. 8(B), the second visual field region 31RR as a whole appears bright red (high brightness red) due to the red component of the white light when the background portion 23 emitting white light is observed through the second optical element 14, similarly to the second visual field region 31RL of Fig. 7 described above. Since cyan is a color obtained by removing the red component from white (complementary color to red), when the second visual target portion 22 emits the second light L2 of cyan color, the figure presented by the second visual target portion 22 becomes a shadow (black due to subtraction of complementary colors) against the transmitted color (red) of the second optical element 14. As a result, the area of ​​the second visual field region 31RR corresponding to the second visual target portion 22 becomes a second shadow portion 36 in which the shape of the second visual target portion 22 is not colored.

[0060] When the first visual target portion 21 emitting the first magenta light L1 is viewed in the field of view of the second opening 12, the action of the second optical element 14 makes it impossible to distinguish between the red component in the white background of the background portion 23 and the magenta color, so that the first visual target portion 21 is buried in the background portion 23 and the subject is unable to recognize the shape of the first visual target portion 21.

[0061] Furthermore, when the second visual target portion 22 emitting the second light L2 of cyan color is viewed in the field of view of the first opening 11, due to the action of the first optical element 13, the green component in the white background of the background portion 23 cannot be distinguished from the cyan color, so that the second visual target portion 22 is buried in the background portion 23 and the subject cannot recognize the shape of the second visual target portion 22.

[0062] Therefore, the shape corresponding to the first target portion 21 is observed as a first shadow portion 35 only in the field of view of the first opening 11 (first field area 30GG). Also, the shape corresponding to the second target portion 22 is observed as a second shadow portion 36 only in the field of view of the second opening 12 (second field area 31RR).

[0063] Fig. 9 shows the visual field area and image observed by a subject using the refractive characteristic measuring device 1 of this embodiment, combining the first visual field area 30GG in Fig. 8(A) and the second visual field area 31RR in Fig. 8(B). When the subject's eye 25 is in the appropriate position relative to the measurement disc 10 as shown in Fig. 2, the first visual field area 30GG and the second visual field area 31RR overlap at the central overlap area 32YY.

[0064] As described above, the first field of view region 30GG and the second field of view region 31RR appear bright and are easy to distinguish by observing the white light emitted by the background portion 23 through the first optical element 13 and the second optical element 14. Also, like the overlapping region 32YL in Fig. 7 described above, the overlapping region 32YY in Fig. 9 appears bright yellow due to the combination (additive color mixing) of the bright green of the first field of view region 30GG and the bright red of the second field of view region 31RR, making it easy for the subject to distinguish.

[0065] The portion corresponding to the first shadow portion 35 is located in the overlapping region 32YL. Then, the portion corresponding to the first shadow portion 35 is seen as a rectangular first optotype image 33RR by the red component light (contained in the second visual field region 31RR) transmitted through the second opening 12 (second optical element 14) out of the white light emitted by the background portion 23. That is, the shape corresponding to the first optotype portion 21 that emits the magenta first light L1 in the light emitting device 20 is observed as a red first optotype image 33RR.

[0066] The portion corresponding to the second shadow portion 36 is located in the overlapping region 32YL. Then, the portion corresponding to the second shadow portion 36 is seen as a rectangular second optotype image 34GG by the green component light (included in the first visual field region 30GG) transmitted through the first opening 11 (first optical element 13) out of the white light emitted by the background portion 23. That is, the shape corresponding to the second optotype portion 22 that emits cyan light in the light emitting device 20 is observed as a green second optotype image 34GG.

[0067] In this way, the color of the first light L1 and the color of the second light L2 are set so that the area corresponding to the first optotype 21 in the first visual field region 30GG becomes the first shadow area 35, and the area corresponding to the second optotype 22 in the second visual field region 31RR becomes the second shadow area 36. In a state where the first visual field region 30GG and the second visual field region 31RR overlap in the overlap area 32YY, the area of ​​the first shadow area 35 becomes the first optotype image 33RR of a single color (red), and the area of ​​the second shadow area 36 becomes the second optotype image 34GG of a single color (green). As a result, the first optotype image 33RR and the second optotype image 34GG do not become images in which a plurality of colors are mixed, as in the first optotype image 33X and the second optotype image 34X shown in FIG. 7, and are easy for the subject to distinguish.

[0068] Therefore, the first visual field area 30GG, the second visual field area 31RR, the overlapping area 32YY, the first optotype image 33RR, and the second optotype image 34GG shown in FIG. 9 are all observed as being high in brightness and easy to distinguish colors, improving the visibility by the subject. More specifically, since the first visual field area 30GG, the second visual field area 31RR, and the overlapping area 32YY can be clearly identified, adjustments for positioning the first optotype image 33RR and the second optotype image 34GG on the overlapping area 32YY are easy to make in the preparation stage for measurement, and it becomes easy to properly align the eye 25 with respect to the refraction characteristic measuring device 1. In addition, since the first optotype image 33RR and the second optotype image 34GG are clearly seen as simple rectangular shapes of single colors of red and green, respectively, it becomes easy to judge the matching state of the first optotype image 33RR and the second optotype image 34GG in the aperture arrangement direction. As a result, the accuracy and efficiency of the test can be improved.

[0069] In the explanation of Fig. 9, the first visual field region 30GG is expressed as light green, the second visual field region 31RR as light red, the first optotype image 33RR as red, and the second optotype image 34GG as green, but this does not mean that the first visual field region 30GG and the second visual field region 31RR always look brighter than the first optotype image 33RR and the second optotype image 34GG. The expressions light green and light red are used to mean that the first visual field region 30GG and the second visual field region 31RR have better visibility than the dark green of the first visual field region 30GD and the dark red of the second visual field region 30RD in the comparative example (Fig. 5).

[0070] The first optotype image 33RR can be easily distinguished and clearly observed in the overlapping region 32YY because the red component contained in the white light of the background portion 23 is placed in the first shadow portion 35. The second optotype image 34GG can be easily distinguished and clearly observed in the overlapping region 32YY because the green component contained in the white light of the background portion 23 is placed in the second shadow portion 36. Therefore, high visibility can be obtained not only for the first visual field region 30GG and the second visual field region 31RR, but also for the first optotype image 33RR and the second optotype image 34GG.

[0071] As described above, the first and second optotypes 21 and 22 are seen in different colors when viewed in the field of view of the first opening 11 (FIG. 8(A)), the second opening 12 (FIG. 8(B)), and the overlapping region of the two fields (overlapping region 32YY) (FIG. 9). For example, if the subject's eye 25 is not in the correct position with respect to the measurement disk 10, the first shadow 35 and the second shadow 36 may not be colored and may not be seen as the red first optotype image 33RR and the green second optotype image 34GG. Therefore, whether or not the subject's eye 25 is in the correct position can be determined based on the appearance of the colors of the parts corresponding to the first and second optotypes 21 and 22, in addition to the appearance of the positional relationship between the first and second visual fields 30GG, 31RR, and the overlapping region 32YY.

[0072] The above effects are obtained by the first opening 11 (first optical element 13) and the second opening 12 (second optical element 14) transmitting light in the green wavelength band and light in the red wavelength band, respectively, the first target portion 21 and the second target portion 22 emitting magenta light and cyan light, which are complementary colors of these two colors, and the background portion 23 emitting white light. Since it is characterized by the spectral characteristics imparted to the first optical element 13 and the second optical element 14 and the color settings of the light emitted from each region of the emission surface of the light emitting device 20, it is excellent in that it does not require a complex structure or control in the refraction characteristic measuring device 1 and can be realized at low cost.

[0073] As mentioned above, green has a high relative luminosity, so by using green as the color of the first visual field region 30GG and the second optotype image 34GG, these parts can be more easily distinguished. Also, by using red as the color of the second visual field region 31RR and the first optotype image 33RR, it becomes easier to visually distinguish them from the first visual field region 30GG and the second optotype image 34GG, which are both green.

[0074] Next, a specific example of condition settings that realize the above-described features will be described in the refraction characteristic measurement apparatus 1. First, the light emitting device 20 will be described.

[0075] It is preferable that the light emitted from the background unit 23 of the light emitting device 20 is white light obtained by combining the following color components a1, b1, and c1. a1: Blue component with maximum intensity at wavelengths between 440nm and 475nm. a2: Green component with maximum intensity at wavelengths of 520mm to 550nm. a3: Red component with maximum intensity at wavelengths of 600 to 650 nm.

[0076] It is preferable that the first light L1 emitted from the first visual target unit 21 of the light emitting device 20 is magenta light obtained by combining the following color components a1 and a3. a1: Blue component with maximum intensity at wavelengths between 440nm and 475nm. a3: Red component with maximum intensity at wavelengths of 600 to 650 nm.

[0077] It is preferable that the second light L2 emitted from the second target unit 22 of the light emitting device 20 is cyan light obtained by combining the following color components a1 and a2. a1: Blue component with maximum intensity at wavelengths between 440nm and 475nm. a2: Green component with maximum intensity at wavelengths of 520mm to 550nm.

[0078] When a transmissive surface light source capable of emitting light in different colors in the first target portion 21, the second target portion 22, and the background portion 23 is used as the light emitting device 20, an LED backlight type or laser backlight type liquid crystal display is suitable in terms of availability and ease of light emission control. In the three primary colors of light emitted by such liquid crystal displays, the central wavelength of the blue component is often in the range of 450nm to 465nm, the central wavelength of the green component is in the range of 530nm to 540nm, and the central wavelength of the red component is in the range of 610nm to 640nm. In consideration of the variation in color development due to individual differences in products and temperature dependency, the values ​​of a1, a2, and a3 are set with a margin of about ±10nm for each range.

[0079] Next, suitable conditions for the spectral characteristics of the first aperture 11 and the second aperture 12 will be described.

[0080] The first optical element 13 provided in the first opening 11 is an optical filter that suppresses the transmission of the first light L1 (magenta color) and transmits the green component of the white light of the background portion 23 that has a maximum intensity at a wavelength of 520 nm to 550 nm, and preferably satisfies the following conditions (1) and (2). (1)T B1 / T G1 <1 / 10 (2)T R1 / T G1 <1 / 10 T G1 : The wavelength λ corresponding to the maximum intensity of the green component (520 nm to 550 nm) of the second light L2 (cyan color) G2 Transmittance at. T B1 : A wavelength λ corresponding to the maximum intensity of the blue component (440 nm to 475 nm) of the first light L1 (magenta color) B1 Transmittance at. T R1 : A wavelength λ corresponding to the maximum intensity of the red component (600 nm to 650 nm) of the first light L1 (magenta color) R1 Transmittance at.

[0081] By satisfying condition (1), the effect of suppressing the transmission of the blue component of the first light L1, which is magenta, can be obtained, thereby reducing crosstalk. By satisfying condition (2), the effect of suppressing the transmission of the red component of the first light L1, which is magenta, can be obtained, thereby reducing crosstalk. Therefore, by using the first optical element 13 that satisfies conditions (1) and (2), it is possible to sufficiently suppress the transmission of the first light L1 and sufficiently transmit the green component of the second light L2.

[0082] The second optical element 14 provided in the second opening 12 is an optical filter that suppresses the transmission of the second light L2 (cyan color) and transmits the red component of the white light of the background portion 23 that has a maximum intensity at a wavelength of 600 nm to 650 nm, and preferably satisfies the following conditions (3) and (4). (3) T B2 / T R2 <1 / 10 (4) T G2 / T R2 <1 / 10 T R2 : A wavelength λ corresponding to the maximum intensity of the red component (600 nm to 650 nm) of the first light L1 (magenta color) R1 Transmittance at. T B2 : The wavelength λ corresponding to the maximum intensity of the blue component (440 nm to 475 nm) of the second light L2 (cyan color) B2 Transmittance at. T G2 : The wavelength λ corresponding to the maximum intensity of the green component (520 nm to 550 nm) of the second light L2 (cyan color) G2 Transmittance at.

[0083] By satisfying condition (3), the effect of suppressing the transmission of the blue component of the second light L2, which is cyan, and reducing crosstalk can be obtained. By satisfying condition (4), the effect of suppressing the transmission of the green component of the second light L2, which is cyan, and reducing crosstalk can be obtained. Therefore, by using the second optical element 14 that satisfies conditions (3) and (4), it is possible to sufficiently suppress the transmission of the second light L2 and sufficiently transmit the red component of the first light L1.

[0084] Next, examples of the light emitting device 20, the first optical element 13, and the second optical element 14 configured using sample products will be shown.

[0085] <Example 1> Light emitting device 20 (LCD display with LED backlight) λ B1 =450nm λ G2 =540nm λ R1 =610nm First optical element 13 (a bandpass filter having a transmittance peak at a wavelength of about 530 nm) T B1 =0.00 T G1 =0.54 T R1 =0.03 T B1 / T G1 =0.00 T R1 / T G1 ≒0.06

[0086] <Example 2> Light emitting device 20 (LCD display with LED backlight) λ B2 =450nm λ G2 =540nm λ R1 =610nm Second optical element 14 (a long-pass filter with a transmission limit wavelength of around 600 nm) T B2 =0.00 T G2 =0.00 T R2 =0.65 T B2 / T G2 =0.00 T R2 / T G2 =0.00

[0087] <Example 3> Light emitting device 20 (liquid crystal display with laser backlight) λ B1 =450nm λ G2 =540nm λ R1 =610nm First optical element 13 (a bandpass filter having a transmittance peak at a wavelength of about 535 nm) T B1 =0.00 T G1 =0.63 T R1 =0.03 T B1 / T G1 =0.00 T R1 / T G1 ≒0.05

[0088] <Example 4> Light emitting device 20 (liquid crystal display with laser backlight) λ B2 =465nm λ G2 =530nm λ R1 =639nm Second optical element 14 (a long-pass filter with a transmission limit wavelength of around 575 nm) T B2 =0.00 T G2 =0.00 T R2 =0.88 T B2 / T G2 =0.00 T R2 / T G2 =0.00

[0089] From the above, the first optical element 13 of each of Examples 1 and 3 satisfies the conditions (1) and (2). In addition, the second optical element 14 of each of Examples 2 and 4 satisfies the conditions (3) and (4). The bandpass filters and longpass filters with the spectral characteristics exemplified in each of the Examples are widely available for use in color correction and color separation in optical instruments, and are highly available.

[0090] Although the above description is based on the illustrated embodiment, the present invention is not limited to the embodiment, and various modifications and changes are possible without departing from the gist of the invention.

[0091] In the above embodiment, the light of the first wavelength band transmitted by the first optical element 13 is green light, and the light of the second wavelength band transmitted by the second optical element 14 is red light, and the first optotype portion 21 emits the first light L1 of magenta color (complementary color of green), and the second optotype portion 22 emits the second light L2 of cyan color (complementary color of red). With this setting, the two visual field areas (first visual field area 30GG, second visual field area 31RR) and two optotype images (first optotype image 33RR, second optotype image 34GG) observed by the subject through the first opening 11 and the second opening 12 are green with high relative luminosity and red close to the psychological complementary color relationship with green, and the visibility by the subject can be improved.

[0092] However, it is also possible to change the color settings from those of the above-described embodiment with respect to the light in the wavelength bands transmitted by the first optical element 13 and the second optical element 14, respectively, the first light L1 emitted by the first visual target portion 21, and the second light L2 emitted by the second visual target portion 22.

[0093] The detailed configuration of the refraction characteristic measuring device may be different from that of the refraction characteristic measuring device 1 of the above-described embodiment. For example, it is possible to select a shape other than a circle as the shape of the first opening 11 and the second opening 12 provided in the measurement disk 10. In addition, the shapes of the first target portion 21 and the second target portion 22 may be a shape other than a rectangle. [Explanation of symbols]

[0094] 1: Refraction characteristic measuring device 10: Measuring disc (opening material) 11: First opening 12: Second opening 13: First optical element 14: Second optical element 20:Light emission device (light emission part) 21:First optotype section 22:Second visual target section 23: Background part 24:Direction indicator 25:Eye 26: Pupil 27: Retina 30GG: 1st visual field 31RR: 2nd visual field 32YY: Overlapping area 33RR: 1st visual target image 34GG: 2nd visual target image 35: 1st shadow part 36:Second shadow part L1: First light L2: Second Light Q: Visual axis

Claims

1. A refractive characteristic measuring device for measuring refractive characteristics of an eye, comprising: A light emitting portion; an aperture member having a first aperture and a second aperture, the aperture member being positioned between the light emitting portion and the eye and configured to narrow and pass the light emitted by the light emitting portion; a first optical element provided in the first opening, the first optical element transmitting light of a first wavelength band and blocking transmission of light of a second wavelength band; a second optical element provided in the second opening, the second optical element transmitting light in the second wavelength band and blocking transmission of light in the first wavelength band; A refraction characteristic measuring device characterized in that the light emitting unit comprises a background unit that emits white light, a first visual target unit that emits a first light that is a complementary color to the light of the first wavelength band, and a second visual target unit that emits a second light that is a complementary color to the light of the second wavelength band.

2. The refraction characteristic measuring device of claim 1, characterized in that the light of the first wavelength band is green light, the light of the second wavelength band is red light, the first light emitted by the first visual target portion is magenta light, and the second light emitted by the second visual target portion is cyan light.

3. the background portion emits the white light by combining a blue component light having a maximum intensity in a wavelength band of 440 nm to 475 nm, a green component light having a maximum intensity in a wavelength band of 520 nm to 550 nm, and a red component light having a maximum intensity in a wavelength band of 600 nm to 650 nm; the first target unit emits the first light by combining the blue light component and the red light component; 3. The refraction characteristic measuring device according to claim 2, wherein the second target unit emits the second light by combining the blue light component and the green light component.

4. 4. The refraction characteristics measuring apparatus according to claim 3, wherein the first optical element satisfies the following conditions (1) and (2): (1)T Ｂ１ / T Ｇ１ <1 / 10 (2)T Ｒ１ / T Ｇ１ <1 / 10 T Ｇ１ : The transmittance of the first optical element at a wavelength corresponding to the maximum intensity of the green component of the second light. T Ｂ１ : The transmittance of the first optical element at a wavelength corresponding to the maximum intensity of the blue component of the first light. T Ｒ１ : The transmittance of the first optical element at a wavelength corresponding to the maximum intensity of the red component of the first light.

5. 4. The refraction characteristics measuring apparatus according to claim 3, wherein the second optical element satisfies the following conditions (3) and (4): (3)T Ｂ２ / T Ｒ２ <1 / 10 (4)T Ｇ２ / T Ｒ２ <1 / 10 T Ｒ２ : The transmittance of the second optical element at a wavelength corresponding to the maximum intensity of the red component of the first light. T Ｂ２ : The transmittance of the second optical element at a wavelength corresponding to the maximum intensity of the blue component of the second light. T Ｇ２ : The transmittance of the second optical element at a wavelength corresponding to the maximum intensity of the green component of the second light.

6. The first opening and the second opening are circular with the same diameter, A refraction characteristic measuring device as described in any one of claims 1 to 5, characterized in that a first optotype image having a shape corresponding to the first optotype portion and a second optotype image having a shape corresponding to the second optotype portion are observed in an overlapping area where a first field of view area observed through the first opening and a second field of view area observed through the second opening overlap.

Images