Ophthalmologic apparatus and ophthalmologic program

Abstract

To provide an ophthalmologic apparatus capable of easily determining ametropia of a subject eye, and an ophthalmologic program.SOLUTION: The ophthalmologic apparatus for objectively measuring the eye refractive power of a subject eye comprises: acquisition means for acquiring at least a spherical refractive power and a cylindrical refractive power as the eye refractive power of the subject eye, the acquisition means acquiring a first cylindrical refractive power of a plus code and a first spherical refractive power corresponding to the first cylindrical refractive power and acquiring a second cylindrical refractive power of a minus code and a second spherical refractive power corresponding to the second cylindrical refractive power; determination means which determines ametropia based on the first spherical refractive power or the second spherical refractive power with a maximum absolute value, and a predetermined threshold value being a determination reference of ametropia for the subject eye; and control means which outputs a result of the determination by the determination means.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an ophthalmic apparatus and an ophthalmic program for objectively measuring the ocular refractive power of a subject's eye. [Background technology]

[0002] As an ophthalmic device, for example, an eye refractive power measuring device is known. For example, as an eye refractive power measuring device, there is known a device that projects a measuring light beam onto the fundus of the examinee's eye and receives the reflected light beam from the fundus with a light receiving element to objectively measure the eye refractive power of the examinee's eye (see Patent Document 1). In addition, as an eye refractive power measuring device, for example, there is known an objective type eye examination device of a photorefraction type that objectively measures the eye refractive power of the examinee's eye from the proportion of the reflected light from the fundus of the examinee's eye at the pupil (see Patent Document 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-147570 A [Patent Document 2] Patent Publication No. 2021-153882 Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned eye refractive power measuring device, the eye refractive power of the test eye can be obtained in two patterns, a positive reading in which the cylindrical refractive power is represented by a positive sign, and a negative reading in which the cylindrical refractive power is represented by a negative sign, but the measurement result is often output in one of the two readings. For example, the examiner judges whether the test eye has a refractive error (for example, myopia, hyperopia, etc.) based on the measurement result of the test eye, but the refractive error may be overlooked depending on the measurement result and the reading. In particular, screening tests and the like are performed on young children such as 3-year-olds in order to detect refractive errors early, but overlooking such refractive errors may be problematic.

[0005] In view of the above problems, the present disclosure has as its technical object to provide an ophthalmic apparatus and an ophthalmic program that can easily determine the refractive error of a subject's eye. [Means for solving the problem]

[0006] In order to solve the above problems, the present invention is characterized by having the following configuration. (1) An ophthalmic apparatus according to a first aspect of the present disclosure is an ophthalmic apparatus for objectively measuring an ocular refractive power of a test eye, characterized in comprising: an acquisition means for acquiring at least a spherical refractive power and a cylindrical refractive power as the ocular refractive power of the test eye, the acquisition means acquiring a first cylindrical refractive power with a positive sign and a first spherical refractive power corresponding to the first cylindrical refractive power, and acquiring a second cylindrical refractive power with a negative sign and a second spherical refractive power corresponding to the second cylindrical refractive power; a determination means for determining the refractive error based on the spherical refractive power with the largest absolute value among the first spherical refractive power and the second spherical refractive power, and a predetermined threshold value which is a criterion for determining a refractive error for the test eye; and a control means for outputting a determination result by the determination means. (2) An ophthalmic apparatus according to a second aspect of the present disclosure is an ophthalmic apparatus for objectively measuring the ocular refractive power of a test eye, characterized in comprising: an acquisition means for acquiring at least a spherical refractive power and a cylindrical refractive power as the ocular refractive power of the test eye, the acquisition means acquiring a first cylindrical refractive power with a positive sign and a first spherical refractive power corresponding to the first cylindrical refractive power, and acquiring a second cylindrical refractive power with a negative sign and a second spherical refractive power corresponding to the second cylindrical refractive power; and a control means for outputting the ocular refractive power of the test eye, the control means outputting the spherical refractive power with the largest absolute value among the first spherical refractive power and the second spherical refractive power. (3) An ophthalmologic program according to a third aspect of the present disclosure is characterized in that it causes a processor to execute an acquisition step of acquiring at least spherical refractive power and cylindrical refractive power as ocular refractive power of a test eye, in which a first cylindrical refractive power with a positive sign and a first spherical refractive power corresponding to the first cylindrical refractive power are acquired, and a second cylindrical refractive power with a negative sign and a second spherical refractive power corresponding to the second cylindrical refractive power; a determination step of determining the refractive error based on the spherical refractive power with the largest absolute value among the first spherical refractive power and the second spherical refractive power, and a predetermined threshold value which is a criterion for determining refractive error for the test eye; and a control step of outputting a determination result obtained by the determination step. (4) An ophthalmologic program according to a fourth aspect of the present disclosure is characterized in that it causes a processor to execute an acquisition step of acquiring at least a spherical refractive power and a cylindrical refractive power as an ocular refractive power of a test eye, in which a first cylindrical refractive power with a positive sign and a first spherical refractive power corresponding to the first cylindrical refractive power are acquired, and a second cylindrical refractive power with a negative sign and a second spherical refractive power corresponding to the second cylindrical refractive power; and a control step of outputting the ocular refractive power of the test eye, in which the spherical refractive power with the largest absolute value is output among the first spherical refractive power and the second spherical refractive power. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram illustrating a configuration of an ophthalmologic apparatus. [Diagram 2] 1 shows a front view of a measurement light source. [Diagram 3] FIG. 1 is a diagram illustrating a photorefraction method. [Figure 4] FIG. 2 is a schematic diagram illustrating a control system in the ophthalmic apparatus. [Diagram 5] FIG. 4 is a diagram illustrating lighting of a measurement light source. [Figure 6] 1 is an example of a display screen. [Figure 7] 13 is an example of a display screen when the subject's eye has no refractive error. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] <Summary> An overview of the ophthalmologic apparatus according to this embodiment will be described. The items classified in <> below can be used independently or in conjunction with each other.

[0009] The ophthalmic apparatus of the present embodiment is an ophthalmic apparatus that objectively measures the ocular refractive power of the subject's eye. For example, at least the spherical refractive power (S) and the cylindrical refractive power (C) may be measured as the ocular refractive power of the subject's eye. Of course, in addition to the spherical refractive power and the cylindrical refractive power, the astigmatism axis angle (A) may be measured as the ocular refractive power of the subject's eye. Furthermore, for example, the equivalent spherical refractive power (SE) based on the spherical refractive power and the cylindrical refractive power may be measured.

[0010] The ophthalmic apparatus of the present embodiment may include a measuring means for objectively measuring the ocular refractive power of the subject's eye. For example, the ophthalmic apparatus may include a measuring means for measuring the ocular refractive power of the subject's eye by a method other than the photorefraction method. In this case, the measuring means may have a configuration for projecting a patterned index as measurement light onto the fundus of the subject's eye, and detecting the reflected light of the measurement light reflected by the fundus with a detector. As an example, the reflected light may be detected as a ring image. As another example, the reflected light may be detected by a Shack-Hartmann sensor. As another example, the ophthalmic apparatus may include a measuring means for measuring the ocular refractive power of the subject's eye by the photorefraction method. In this case, the measuring means may have a configuration for projecting a non-patterned index as measurement light onto the fundus of the subject's eye, and detecting the reflected light of the measurement light reflected by the fundus with a detector. As an example, the state of the light flux at the pupil of the subject's eye (the ratio of the light flux at the pupil, etc.) may be detected.

[0011] For example, the photorefraction type measuring means may have a light projecting optical system (for example, the light projecting optical system 10) and a light receiving optical system (for example, the light receiving optical system 20). For example, the light projecting optical system and the light receiving optical system may be configured with different optical members, or may be configured to share at least some optical members.

[0012] For example, the light projection optical system may have at least a measurement light source. For example, the light projection optical system may have a plurality of measurement light sources (e.g., measurement light source 13) arranged in a meridian direction (radial direction) with respect to the optical axis center, and may irradiate the measurement light beams emitted from the plurality of measurement light sources to the fundus of the subject's eye. For example, the plurality of measurement light sources may be independently controlled. For example, the turning on and off of each measurement light source, the adjustment of the light amount, etc. may be independently controlled. Also, the plurality of measurement light sources may be arranged separately from each other with respect to at least three meridian directions with respect to the optical axis center. For example, by arranging the measurement light sources in at least three meridian directions, it is possible to measure the ocular refractive power including the spherical refractive power, the cylindrical refractive power, the astigmatism axis angle, etc. The meridian direction in which the measurement light sources are arranged may be any number of meridian directions (e.g., the first meridian direction, the second meridian direction, the third meridian direction, the fourth meridian direction, etc.). Also, it is sufficient that at least one measurement light source is arranged in each meridian direction.

[0013] For example, the light receiving optical system may have at least a detector. For example, the light receiving optical system may detect the reflected light of the measurement light reflected by the fundus of the subject's eye with a detector (for example, detector 21).

[0014] <Acquisition method> The ophthalmologic apparatus of the present embodiment may include an acquisition means (e.g., a control unit 80). For example, the acquisition means is an acquisition means for acquiring at least a spherical refractive power and a cylindrical refractive power as the ocular refractive power of the subject's eye, and acquires a first cylindrical refractive power with a plus sign and a first spherical refractive power corresponding to the first cylindrical refractive power, and acquires a second cylindrical refractive power with a minus sign and a second spherical refractive power corresponding to the second cylindrical refractive power. For example, in the ocular refractive power of the subject's eye, the cylindrical refractive power can be acquired in two patterns, that is, when it is expressed by a plus sign (in other words, when it is read as a plus sign) and when it is expressed by a minus sign (in other words, when it is read as a minus sign). For example, the spherical refractive power corresponding to the cylindrical refractive power changes depending on whether the cylindrical refractive power is read as a plus sign or a minus sign. Therefore, for example, the first spherical refractive power corresponding to the first cylindrical refractive power with a plus sign and the second spherical refractive power corresponding to the second cylindrical refractive power with a minus sign are expressed by values ​​different from each other.

[0015] For example, the positive and negative readings of the cylindrical refractive power of the subject's eye are determined by the refractive power of the subject's eye in the meridian direction. More specifically, the cylindrical refractive power of the subject's eye is obtained in two patterns, positive and negative, depending on which meridian direction the cylindrical refractive power of the subject's eye is represented by, for example, the meridian direction in which the subject's eye has the strongest refractive power (principal meridian) and the meridian direction in which the subject's eye has the weakest refractive power (principal meridian).

[0016] For example, the acquisition unit may acquire at least the spherical refractive power and the cylindrical refractive power by receiving a measurement result measured using an ophthalmic device other than that of the present embodiment, which is capable of objectively measuring the ocular refractive power of the subject's eye. In other words, the ophthalmic device of the present embodiment may function as an information analysis device. Of course, the ophthalmic device of the present embodiment may include the above-mentioned measuring unit. In this case, for example, the acquisition unit may acquire at least the spherical refractive power and the cylindrical refractive power based on the measurement result by the measuring unit.

[0017] <Judgment means> The ophthalmologic apparatus of the present embodiment may include a determination means (for example, a control unit 80). For example, the determination means determines the refractive error based on the spherical refractive power with the maximum absolute value among the first spherical refractive power corresponding to the first cylindrical refractive power with a plus sign and the second spherical refractive power corresponding to the second cylindrical refractive power with a minus sign, and a predetermined threshold value that is a determination criterion for refractive error for the eye to be examined. At this time, for example, the spherical refractive power with the maximum absolute value may be used to determine the refractive error based on the first spherical refractive power corresponding to the first cylindrical refractive power with a plus sign and the second spherical refractive power corresponding to the second cylindrical refractive power with a minus sign. For example, the determination means may determine that there is a refractive error when the spherical refractive power with the maximum absolute value exceeds a predetermined threshold value. Also, for example, the determination means may determine that there is no refractive error when the spherical refractive power with the maximum absolute value does not exceed a predetermined threshold value. For example, by using the spherical refractive power with the largest absolute value, refractive error can be easily determined even in cases where the spherical refractive power corresponding to one cylindrical power reading does not exceed a predetermined threshold value, but the spherical refractive power corresponding to the other cylindrical power reading exceeds a predetermined threshold value.

[0018] For example, the determination means may determine refractive error by comparing only the spherical power having the maximum absolute value among the first spherical power and the second spherical power with a predetermined threshold value.

[0019] For example, when the determining means compares only the spherical power with the maximum absolute value with the threshold value, the spherical power with the maximum absolute value may be obtained by directly comparing the first spherical power with the second spherical power.As an example, when the first spherical power is -2.50D and the second spherical power is -1.50D, the second spherical power with the maximum absolute value may be obtained by comparing them with each other.

[0020] Also, for example, when the determination means compares only the spherical refractive power with the threshold value, the spherical refractive power with the maximum absolute value may be acquired based on the sign of the first equivalent spherical refractive power by the first spherical refractive power and the first cylindrical refractive power. Alternatively, the spherical refractive power with the maximum absolute value may be acquired based on the sign of the second equivalent spherical refractive power by the second spherical refractive power and the second cylindrical refractive power. Note that, for example, the first equivalent spherical refractive power and the second equivalent spherical refractive power have the same value, so either one may be used. As an example, if the equivalent spherical refractive power has a negative sign, the first spherical refractive power corresponding to the cylindrical refractive power with a positive sign may be acquired as the spherical refractive power with the maximum absolute value. As an example, if the equivalent spherical refractive power has a positive sign, the second spherical refractive power corresponding to the cylindrical refractive power with a negative sign may be acquired as the spherical refractive power with the maximum absolute value. For example, the determination means may obtain a spherical refractive power corresponding to a cylindrical refractive power reading that has a sign opposite to that of the equivalent spherical refractive power, thereby obtaining the spherical refractive power with the maximum absolute value.

[0021] For example, the judgment means may judge refractive error by comparing both the first spherical power and the second spherical power with a predetermined threshold. As an example, the judgment means may compare both the first spherical power and the second spherical power with a predetermined threshold, and judge refractive error when at least one of the first spherical power and the second spherical power exceeds the predetermined threshold. Note that either the first spherical power or the second spherical power corresponds to the spherical power with the maximum absolute value, and by comparing both of them with a threshold, refractive error can be easily judged.

[0022] For example, the predetermined threshold may be a criterion set for determining at least one of myopia and hyperopia as a refractive error. For example, the predetermined threshold may be at least one or more specific values, a specific tolerance range, or the like.

[0023] For example, the predetermined threshold may be a fixed value set in advance. For example, in this case, the predetermined threshold may be a value set in advance based on an experiment or a simulation. Also, for example, the predetermined threshold may be an arbitrary value set based on an operation signal. For example, in this case, the examiner may operate an operation means (for example, the controller 81) to output an operation signal. Also, for example, in this case, an external storage means (for example, an SD card, a USB memory, a server, a cloud, etc.) may be used to read data stored in the external storage means to output an operation signal.

[0024] <Settings> The ophthalmologic apparatus of the present embodiment may include a setting means (e.g., a control unit 80). For example, the setting means sets which of a first cylindrical refractive power with a plus sign and a second cylindrical refractive power with a minus sign is to be output as the cylindrical refractive power of the eye refractive power of the subject eye. For example, since the cylindrical refractive power of the subject eye can be obtained in two patterns, a plus reading and a minus reading, the output method may be set so that one of the readings is given priority.

[0025] For example, the setting means may set which of the first and second cylindrical powers to be output based on a selection signal of either the first or second cylindrical power input by the examiner operating the operating means. Also, for example, the setting means may automatically set which of the first and second cylindrical powers to be output based on a judgment result of the judging means described later.

[0026] <Control means> The ophthalmologic apparatus of this embodiment may include a control means (e.g., a control unit 80). For example, the control means outputs the judgment result of the judgment means. For example, the judgment result may be one that can inform the examiner of the refractive error of the examinee's eye. For example, the judgment result may directly or indirectly indicate that there is a refractive error, or may directly or indirectly indicate that there is no refractive error. Of course, for example, the judgment result may include both an indication of the presence of a refractive error and an indication of the absence of a refractive error. This allows the examiner to easily judge the refractive error, and as a result, it is possible to reduce overlooking the refractive error of the examinee's eye.

[0027] For example, the control means may directly output the judgment result of the judgment means. In this case, the judgment result may be that the first spherical refractive power or the second spherical refractive power of the subject eye (in other words, the spherical refractive power with the maximum absolute value) exceeds or does not exceed a predetermined threshold value that is a criterion for judging refractive error.

[0028] Also, for example, the control means may output various information based on the judgment result as the judgment result of the judgment means. In this case, the judgment result may be output as notification information for notifying the examiner of the presence or absence of refractive error. As an example, the notification information may be at least one of information indicating the presence or absence of refractive error, information indicating the degree of refractive error (e.g., a numerical value or an evaluation index), etc. Also, in this case, the judgment result may be output as guidance information for guiding the examiner. As an example, the guidance information may be at least one of information indicating the end of the examination of the subject's eye, information indicating the examiner's next action, information indicating instructions to the subject, etc.

[0029] For example, the control means may control a display means and cause the display means to display the determination result. Also, for example, the control means may control a sound generation means (for example, a speaker) and cause the sound generation means to generate the determination result as sound. Also, for example, the control means may control an informing means (for example, a lamp) and cause the informing means to light up or blink to indicate the determination result. Also, for example, the control means may control a printing means (for example, a printer) and cause the printing means to print the determination result. Also, for example, the control means may control an external storage means (for example, a memory or a server) and transmit the determination result to the external storage means. Of course, for example, the control means may execute a combination of these controls, or may execute a different control from these controls.

[0030] For example, when the control means controls the display means, the determination result may be displayed on the display means as a message. Also, for example, the determination result may be displayed by highlighting the screen on the display means. One example may be at least one of reversing or changing the color of the screen, blinking the screen, changing the display size, etc. Also, for example, the determination result may be displayed by displaying a sign (for example, at least one of a window, a mark, an icon, letters, numbers, symbols, etc.) on the display means. Of course, the determination result may be displayed, for example, by further highlighting such a sign.

[0031] In this embodiment, the control means may output the eye refractive power of the subject's eye. In this case, the control means may output the spherical refractive power with the maximum absolute value among the first spherical refractive power corresponding to the first cylindrical refractive power with a plus sign and the second spherical refractive power corresponding to the second cylindrical refractive power with a minus sign. At this time, for example, the spherical refractive power with the maximum absolute value may be used for output based on the first spherical refractive power corresponding to the first cylindrical refractive power with a plus sign and the second spherical refractive power corresponding to the second cylindrical refractive power with a minus sign. That is, the spherical refractive power with the larger absolute value among the first spherical refractive power and the second spherical refractive power may be used for output. In this case, the spherical refractive power with the maximum absolute value can be confirmed as the spherical refractive power of the subject's eye, so that it is easy to determine whether the subject's eye has a refractive error and it is possible to reduce overlooking of refractive errors. Of course, the control means may output, in addition to the spherical power having the maximum absolute value, the corresponding cylindrical power, equivalent spherical power, cylinder axis angle, etc.

[0032] In the present embodiment, the control means may output the ocular refractive power of the subject's eye together with the judgment result. In this case, the control means for outputting the ocular refractive power of the subject's eye and the control means for outputting the judgment result of the subject's eye may be combined or may be provided separately.

[0033] For example, when the determination means determines that the spherical refractive power with the maximum absolute value is less than a predetermined threshold value, the control means may output the cylindrical refractive power with the sign set by the setting means and the spherical refractive power corresponding to the cylindrical refractive power with the sign set by the setting means as the ocular refractive power. In other words, the ocular refractive power may be output according to either the positive or negative reading of the cylindrical refractive power set by the setting means. Also, for example, when the determination means determines that the spherical refractive power with the maximum absolute value is equal to or greater than a predetermined threshold value, the control means may output the spherical refractive power with the maximum absolute value and the cylindrical refractive power corresponding to the spherical refractive power with the maximum absolute value as the ocular refractive power, regardless of the sign set by the setting means. In other words, regardless of the positive or negative reading of the cylindrical refractive power set by the setting means, the ocular refractive power may be output in the reading of the spherical refractive power with the maximum absolute value and the cylindrical refractive power corresponding to this spherical refractive power. This makes it easier for the examiner to grasp whether the spherical refractive power of the subject's eye exceeds the standard, and allows the examiner to easily determine the refractive error of the subject's eye.

[0034] The present disclosure is not limited to the device described in the present embodiment. For example, the terminal control software (program) that performs the functions of the above embodiment can be supplied to a system or device via a network or various storage media, and the control device (e.g., CPU, etc.) of the system or device can read and execute the program.

[0035] For example, such terminal control software may cause a processor to execute the following steps: an acquisition step of acquiring at least spherical refractive power and cylindrical refractive power as the ocular refractive power of the test eye, where a first cylindrical refractive power with a positive sign and a first spherical refractive power corresponding to the first cylindrical refractive power are acquired, and a second cylindrical refractive power with a negative sign and a second spherical refractive power corresponding to the second cylindrical refractive power are acquired; a determination step of determining refractive error based on the spherical refractive power with the largest absolute value among the first spherical refractive power and the second spherical refractive power, and a predetermined threshold value that is a criterion for determining refractive error for the test eye; and a control step of outputting the determination result by the determination step. As an example, the terminal control software may be executed by a processor mounted on an ophthalmic device.

[0036] Also, for example, such terminal control software may cause a processor to execute the following: an acquisition step of acquiring at least spherical refractive power and cylindrical refractive power as the ocular refractive power of the test eye, where the acquisition step acquires a first cylindrical refractive power with a positive sign and a first spherical refractive power corresponding to the first cylindrical refractive power, and acquires a second cylindrical refractive power with a negative sign and a second spherical refractive power corresponding to the second cylindrical refractive power; and a control step of outputting the ocular refractive power of the test eye, where the control step outputs the spherical refractive power with the largest absolute value among the first spherical refractive power and the second spherical refractive power. As an example, the terminal control software may be executed by a processor mounted on an ophthalmic device.

[0037] <Example> An embodiment of the ophthalmic apparatus in this embodiment will be described below. For example, Fig. 1 is a diagram for explaining the configuration of the ophthalmic apparatus. In this embodiment, a configuration in which the light projecting optical system and the light receiving optical system are used in both left and right measurements of the subject eye will be described as an example. In other words, a case in which the left and right measurements of the subject eye are performed by one light projecting optical system and one light receiving optical system will be described as an example.

[0038] <Apparatus appearance> For example, the ophthalmic apparatus 1 objectively measures the ocular refractive power of the subject's eye by a photorefraction method. For example, a configuration for objectively measuring the ocular refractive power of the subject's eye by a photorefraction method refers to a configuration for objectively measuring the ocular refractive power of the subject's eye from the ratio of reflected light from the fundus of the subject's eye to the pupil. For example, in this embodiment, the ophthalmic apparatus 1 includes a housing 2. For example, the housing 2 houses therein an optical system (e.g., a light projecting optical system 10, a light receiving optical system 20) for objectively measuring the ocular refractive power of the subject's eye by a photorefraction method.

[0039] <Measurement optical system> For example, the ophthalmic apparatus 1 includes a light projecting optical system 10 and a light receiving optical system 20. In this embodiment, for example, the light projecting optical system 10 includes a measurement light source 13. Of course, for example, the light projecting optical system 10 may be composed of only the measurement light source 13. For example, the light receiving optical system 20 includes a detector 21 (for example, a CCD or the like) and a light receiving objective optical system 25.

[0040] For example, the presentation window 3 transmits the measurement light emitted from the measurement light source 13 in the light projection optical system 10. Therefore, the subject's eye E is irradiated with the measurement light through the presentation window 3. For example, the presentation window 3 is covered with a transparent panel to prevent the intrusion of dust and the like. For example, the transparent panel can be made of a transparent material such as an acrylic resin or a glass plate.

[0041] 2 shows the measurement light source 13 as viewed from the front (optical axis direction) (when the subject views the measurement light source 13). For example, a red LED (light emitting diode) that emits near-infrared light is used as the measurement light source 13. Of course, a different type of light source may be used.

[0042] For example, in this embodiment, the measurement light source 13 also serves as an anterior eye illumination light source that illuminates the anterior eye of the subject's eye. Of course, a separate dedicated anterior eye illumination light source for illuminating the anterior eye image may be provided. Also, for example, in this embodiment, the detector 21 also serves as a detector that captures the anterior eye image illuminated by the anterior eye illumination light source. Of course, a separate dedicated detector for capturing the anterior eye image may be provided. For example, the captured anterior eye image is displayed on the display 11.

[0043] For example, in this embodiment, the measurement light source 13 also serves as a fixation light for fixing the subject's eye. Of course, a separate fixation light dedicated to fixing the subject's eye may be provided. For example, when a fixation light is provided, it may be provided on the optical axis or in the vicinity of the optical axis.

[0044] For example, a plurality of measurement light sources may be provided as the measurement light source 13, and each measurement light source may be arranged separately from each other in at least three meridian directions. Of course, the meridian directions in which the measurement light sources are arranged may be any number of meridian directions (for example, one meridian direction, two meridian directions, four meridian directions, etc.). In this embodiment, a case where the measurement light sources are arranged in four meridian directions will be described as an example. Also, in this embodiment, a case where the measurement light sources 13 are arranged in order on a virtual straight line extending in the meridian directions with the optical axis center as a reference will be described as an example.

[0045] In this embodiment, a configuration in which two sets of measurement light sources are arranged symmetrically with respect to the optical axis center O1 of the objective lens 26 in one meridian direction will be described as an example. Of course, a configuration in which measurement light sources are not arranged symmetrically with respect to the optical axis center O1 of the objective lens 26 in one meridian direction may be used. That is, a configuration in which measurement light sources are arranged only on one side of the optical axis center O1 of the objective lens 26 in one meridian direction may be used. In this embodiment, for example, eight sets of measurement light sources (measurement light source 13a, measurement light source 13b, measurement light source 13c, measurement light source 13d, measurement light source 13e, measurement light source 13f, measurement light source 13g, measurement light source 13h) are arranged in four meridian directions as the measurement light source 13.

[0046] For example, eight sets of measurement light sources, measurement light sources 13a to 13h, are arranged at 45° intervals on a concentric circle outside the outer circumferential circle of the objective lens 26. Of course, the arrangement position of each measurement light source can be any position. For example, the measurement light source 13 is fixed to the base 14. Also, for example, the objective lens 26 is fixed to the base 14.

[0047] For example, each of the eight sets of measurement light sources, 13a to 13h, has three measurement light sources. For example, the three light sources (for example, the three light sources 13a1, 13a2, and 13a3 in the measurement light source 13a) are sequentially arranged at a predetermined interval in the meridian direction (radial direction) with respect to the optical axis center O1 of the objective lens 26. For example, each measurement light source can be controlled independently. For example, the lighting, adjustment of the light amount, etc. of each measurement light source can be controlled independently.

[0048] In this embodiment, for example, the measurement light source 13 has eight sets of measurement light sources, but is not limited to this. For example, the measurement light source 13 can have any set (for example, three sets, four sets, five sets, six sets, etc.) of measurement light sources. In this embodiment, the eight sets of measurement light sources 13a to 13h are described as having three measurement light sources each, but are not limited to this. Each set of measurement light sources can have any number of measurement light sources (for example, two, four, five, etc.).

[0049] For example, the measurement light source 13 is arranged concentrically outside the outer circumferential circle of the objective lens 26 as described above.

[0050] For example, the detector 21 is in a conjugate relationship with the pupil of the subject's eye. For example, the output from the detector 21 is input to the control unit 80. In this embodiment, for example, the optical axis L2 of the light receiving optical system 20 and the optical axis L1 of the light projecting optical system 10 are coaxial.

[0051] In the above configuration, the measurement light emitted from the measurement light source 13 proceeds toward the subject's eye E. For example, the measurement light is irradiated onto the fundus of the subject's eye E through the presentation window 3. That is, the measurement light is irradiated onto the subject's eye E along the optical axis L1 of the light projection optical system 10. In this embodiment, the measurement light is irradiated onto the left and right subject's eyes (left and right eyes).

[0052] For example, the measurement light irradiated onto the fundus of the subject's eye E is reflected and scattered, exits the subject's eye E, and is collected by the objective lens 26. The reflected light collected by the objective lens 26 is detected by the detector 21. In this embodiment, the reflected light reflected by each of the left and right eyes is detected by the detector 21.

[0053] In this embodiment, for example, the measurement light source 13 is turned on in sequence. For example, the control unit 80 turns on the measurement light source 13a1. At this time, the other measurement light sources are turned off. For example, the measurement light emitted from the measurement light source 13a1 is irradiated to the test eye E, and the reflected light reflected by the test eye E is detected by the detector 21. For example, when the control unit 80 obtains a detection result by turning on the measurement light source 13a1, it turns on the next measurement light source 13a2 and turns off the measurement light source 13a1, and obtains a detection result by turning on the measurement light source 13a2. For example, when the control unit 80 obtains a detection result by turning on the measurement light source 13a2, it turns on the next measurement light source 13a3 and turns off the measurement light source 13a2, and obtains a detection result by turning on the measurement light source 13a3.

[0054] For example, when the control unit 80 obtains the detection results by the three light sources of the measurement light source 13a, it performs measurement by the next set of measurement light sources. For example, the control unit 80 obtains the detection results by the three light sources of the measurement light source 13b. In this case, the measurement light source 13b1 is turned on, and the other measurement light sources are turned off. Next, similar to the measurement of the measurement light source 13a described above, the control unit 80 sequentially obtains the detection results by each measurement light source. For example, when the control unit 80 obtains the detection results by the three light sources of the measurement light source 13a, it performs measurement by the next set of measurement light sources. For example, the control unit 80 sequentially performs measurements by each set of measurement light sources.

[0055] In this embodiment, the measurement light sources are turned on as described above, but the present invention is not limited to this. The measurement light sources can be turned on in any order.

[0056] <Photorefraction method> Next, for example, the photorefraction method will be described. Fig. 3 is a diagram for explaining the photorefraction method. In this embodiment, for example, the control unit 80 detects the reflected light from the fundus passing through the pupil with the detector 21, detects the ratio of the dimension of the bright crescent in the pupil in the pupil radial direction to the pupil diameter, and obtains the eye refractive power by the following formula 1 (for example, see JP 2006-149501 A).

[0057]

number

[0058] Here, R indicates the dimensional ratio (B / 2r) of the bright crescent K in the pupil to the pupil diameter. For example, B is the length of the bright crescent K in the pupil radial direction. For example, r is the pupil radius of the test eye. For example, A is the ocular refractive power of the test eye. For example, e is the distance from the end 26a of the objective lens 26 to the measurement light source 13 (in FIG. 3, measurement light source 13a1 in measurement light source 13 is exemplified). For example, L is the reciprocal of the separation distance (measurement distance) S between the test eye E and the objective lens 26 (L=1 / S).

[0059] As described above, for example, the proportion R of the bright crescent B, assuming other conditions are constant, varies depending on the ocular refractive power A of the test eye. In other words, the ocular refractive power A of the test eye is calculated from the proportion R of the bright crescent measured under constant conditions by the following Equation 2.

[0060]

number

[0061] In this manner, the ocular refractive power of the subject's eye is calculated by the photorefraction method.

[0062] In this embodiment, for example, the projection optical system 10 and the receiving optical system 20 in Fig. 1 may be arranged in any manner. As an example, the projection optical system 10 and the receiving optical system 20 may be arranged in different positions and measurements may be performed with different optical axes.

[0063] <Control Unit> 4 is a schematic configuration diagram of a control system in the ophthalmologic apparatus 1. For example, a display (monitor) 11, a measurement light source 13, a detector 21, a controller 81, a non-volatile memory 82, and the like are connected to a control unit 80.

[0064] For example, the control unit 80 includes a CPU (processor), a RAM, a ROM, etc. For example, the CPU controls each component in the ophthalmic apparatus 1. For example, the RAM temporarily stores various information. For example, the ROM stores various programs for controlling the operation of the ophthalmic apparatus 1. Note that the control unit 80 may be configured with multiple control units (i.e., multiple processors).

[0065] For example, the controller 81 is used to switch the display on the display 11 or to start measurement by turning on the measurement light source 13. For example, a signal input from the controller 81 is input to the control unit 80 via a cable. Note that in this embodiment, the signal from the controller 81 may be input to the control unit 80 via wireless communication such as infrared. For example, the controller 81 may be at least one of a mouse, a joystick, a keyboard, a touch panel, and the like.

[0066] For example, in this embodiment, the controller 81 is provided in the housing 2. More specifically, the controller 81 is provided in the periphery of the display 11. Of course, the controller 81 can be disposed in any position, and may be provided as a configuration different from the housing 2.

[0067] For example, the display 11 may be a display mounted on the main body of the ophthalmic device 1, or may be a display connected to the main body of the ophthalmic device 1. A display of a personal computer (hereinafter referred to as "PC") may be used. A plurality of displays may be used in combination. Furthermore, the display 11 may be a touch panel. When the display 11 is a touch panel, the display 11 functions as a controller. An image of the examinee's eye, etc., is displayed on the display 11.

[0068] For example, the non-volatile memory 82 is a non-transient storage medium that can retain stored contents even if the power supply is cut off. For example, a hard disk drive, a flash ROM, a USB memory, etc. can be used as the non-volatile memory (hereinafter, referred to as memory) 82. For example, the memory 82 stores a measurement processing program.

[0069] <Control action> A control operation in the ophthalmic apparatus 1 having the above-mentioned configuration will be described. In this embodiment, a case where a screening test is performed on a child, such as a three-year-old child, using the ophthalmic apparatus 1 will be described as an example. For example, a photorefraction type measurement such as that of the ophthalmic apparatus 1 does not necessarily require strict (severe) alignment, and measurement results can be obtained simply and efficiently. For this reason, it is often used for the purpose of screening refractive errors (myopia and hyperopia, for example) of the examined eye, particularly for children who have difficulty in maintaining fixation on the test target.

[0070] <Obtaining objective refractive power of the test eye> For example, an examiner uses the ophthalmologic apparatus 1 to obtain the objective refractive power of the subject's eye. In this embodiment, measurements of the left and right eyes are performed simultaneously. Of course, the measurements of the left and right eyes may be performed at different times. For example, after the measurement of one subject's eye is completed, the measurement of the other subject's eye may be started.

[0071] For example, the examiner instructs the subject to observe the measurement light source 13 of the ophthalmic device 1. For example, the measurement light source 13 illuminates the anterior eye including the pupil of the subject, and the anterior eye image illuminated by the measurement light source 13 is detected by the detector 21. For example, the control unit 80 displays the anterior eye image detected by the detector 21 on the display 11. For example, the examiner adjusts the position of the ophthalmic device 1 so that the left and right test eyes of the subject are displayed on the display 11 of the ophthalmic device 1. For example, the control unit 80 may display on the display 11 that the alignment is complete when the left and right test eyes of the subject are displayed on the display 11. Of course, the examiner may confirm that the left and right test eyes of the subject are displayed on the display 11 of the ophthalmic device 1 and recognize that the alignment is complete.

[0072] For example, when the alignment is completed, the examiner operates the controller 81 and selects a switch for starting the measurement. For example, the control unit 80 issues a measurement start trigger signal (hereinafter, referred to as a trigger signal) for starting the measurement based on the output of an operation signal from the controller 81. For example, when the trigger signal for starting the measurement is issued, the control unit 80 emits measurement light from the measurement light source 13 of the light projecting optical system 10. For example, the measurement light emitted from the measurement light source 13 is projected onto the fundus of the subject's eye E. In this embodiment, the measurement light is irradiated onto the fundus of the left and right eyes. The reflected light of the measurement light reflected from the fundus is detected by the detector 21 of the light receiving optical system 20.

[0073] For example, the control unit 80 turns on each measurement light source of the measurement light source 13 in sequence, and detects the reflected light from the subject's eye by each measurement light source with the detector 21. For example, the output signal from the detector 21 is stored as image data (measurement image) in the memory 82. In this embodiment, image data of the left and right eyes are respectively acquired, and the image data (measurement image) of the left and right eyes are stored in the memory 82. Thereafter, the control unit 80 analyzes the images stored in the memory 82 to obtain values ​​of the first ocular refractive power of the left and right eyes.

[0074] A more detailed description will be given. For example, the control unit 80 calculates spherical information (spherical refractive power) in the direction in which the measurement light source 13a is arranged based on the detection result detected by turning on the measurement light source 13a (three measurement light sources 13a1 to 13a3). For example, when calculating the spherical information in the direction in which the measurement light source 13a is arranged, the control unit 80 acquires the spherical information in the arrangement direction of the measurement light source 13a based on at least one of the measurement results acquired by turning on the three measurement light sources 13a1 to 13a3. In this case, for example, the control unit 80 may acquire the average value of the spherical information acquired from each of the three measurement light sources 13a1 to 13a3 as the spherical information in the arrangement direction of the measurement light source 13a. In addition, in this case, for example, the control unit 80 may select one piece of spherical information from the three measurement light sources 13a1 to 13a3 and acquire it as the spherical information in the arrangement direction of the measurement light source 13a.

[0075] For example, when the spherical information in the arrangement direction of the measurement light source 13a is acquired as described above, the control unit 80 then acquires spherical information in each arrangement direction of the other measurement light sources 13b to 13h in the same manner as described above.

[0076] Fig. 5 is a diagram for explaining the lighting of the measurement light source 13. In Fig. 5, the measurement light source used in the normal measurement mode among the measurement light source (plurality of measurement light sources) 13 is shown hatched (filled in). As described above, each measurement light source in the measurement light source 13 is turned on in sequence, and as a result, all light sources of the measurement light source 13 are turned on in sequence to perform measurement (all measurement light sources are shown as hatched areas).

[0077] In this embodiment, spherical refractive power, cylindrical refractive power, and cylindrical axis angle are acquired as the ocular refractive power. For example, when the spherical information in each direction is acquired, the control unit 80 acquires the spherical refractive power based on the spherical information in each direction. For example, the average value of the spherical refractive power acquired in each direction may be set as the spherical refractive power. Of course, the spherical refractive power may be acquired based on at least one or more of the spherical refractive powers in each direction. Also, for example, the control unit 80 acquires the cylindrical refractive power and the cylindrical axis angle based on the spherical refractive power (spherical refractive power distribution) in each direction. That is, for example, the control unit 80 acquires the ocular refractive power of the spherical refractive power (S), the cylindrical refractive power (C), and the cylindrical axis angle (A).

[0078] Here, for example, the eye refractive power of the subject eye is acquired in two patterns, the first eye refractive power and the second eye refractive power. For example, the first eye refractive power may include a first spherical refractive power, a first cylindrical refractive power, and a first cylindrical axis angle. Also, for example, the second eye refractive power may include a second spherical refractive power, a second cylindrical refractive power, and a second cylindrical axis angle. For example, in the first eye refractive power, the first cylindrical refractive power is a cylindrical refractive power represented by a plus sign (that is, a cylindrical refractive power with a plus reading). Also, for example, the first spherical refractive power is a spherical refractive power corresponding to such a cylindrical refractive power represented by a plus sign. Similarly, for example, in the second eye refractive power, the second cylindrical refractive power is a cylindrical refractive power represented by a minus sign (that is, a cylindrical refractive power with a minus reading). Also, for example, the second spherical power is a spherical power corresponding to such a cylindrical power expressed with a minus sign.

[0079] In this embodiment, the first and second refractive powers of the left eye and the first and second refractive powers of the right eye are acquired. For example, for the left eye, the first refractive power is acquired as the first refractive power, with a first spherical refractive power of -1.50D, a first cylindrical refractive power of +0.50D, and a first cylindrical axis angle of 180°. Also, for the second refractive power, the second spherical refractive power of -1.00D, a second cylindrical refractive power of -0.50D, and a second cylindrical axis angle of 90° are acquired. For example, for the right eye, the first refractive power is acquired as the first refractive power, with a first spherical refractive power of -2.50D, a first cylindrical refractive power of +1.50D, and a first cylindrical axis angle of 180°. In addition, the second spherical refractive power is −1.00D, the second cylindrical refractive power is −1.50D, and the second cylindrical axis angle is 90° as the second refractive power. In the left eye and the right eye, the first cylindrical refractive power is a positive reading, and the second cylindrical refractive power is a negative reading, so that the signs are reversed. In addition, depending on how the first cylindrical refractive power and the second cylindrical refractive power are read, the corresponding first spherical refractive power and the second spherical refractive power have different values. For example, the first refractive power and the second refractive power of the left eye and the right eye are stored in the memory 82.

[0080] <Selection of screening value> For example, when the control unit 80 acquires the first and second refractive powers of the subject's eye, the control unit 80 selects the spherical refractive power with the maximum absolute value from the first spherical refractive power corresponding to the first cylindrical refractive power with a plus sign (plus reading) and the second spherical refractive power corresponding to the second cylindrical refractive power with a minus sign (minus reading) as a screening value for determining refractive error of the subject's eye. More specifically, for example, the control unit 80 compares the first and second spherical refractive powers to select the spherical refractive power with the maximum absolute value as a screening value.

[0081] First, the left eye will be described. For example, the first spherical power corresponding to the positive reading of the left eye is -1.50D, and the second spherical power corresponding to the negative reading of the left eye is -1.00D. For this reason, for example, the control unit 80 obtains the absolute values ​​of the first spherical power -1.50D and the second spherical power -1.00D, and further compares the absolute values ​​of each other to select the spherical power with the larger absolute value as the screening value. For example, here, the second spherical power corresponding to the negative reading is selected as the screening value.

[0082] Next, the right eye will be described. For example, the first spherical power corresponding to the positive reading of the right eye is -2.50D, and the second spherical power corresponding to the negative reading of the right eye is -1.00D. Therefore, for example, the control unit 80 obtains the absolute values ​​of the first spherical power -2.50D and the second spherical power -1.00D, and further compares the absolute values ​​of each other to select the spherical power with the larger absolute value as the screening value. For example, here, the first spherical power corresponding to the positive reading is selected as the screening value.

[0083] <Assessment of refractive errors> For example, when the control unit 80 selects a spherical refractive power corresponding to a positive or negative reading of the subject's eye as a screening value, the control unit 80 judges whether or not the screening value exceeds a predetermined threshold value which is a criterion for judging the refractive error of the subject's eye. For example, the control unit 80 judges whether or not the screening value exceeds a first threshold value which is a criterion for judging myopia and whether or not it exceeds a second threshold value which is a criterion for judging hyperopia.

[0084] For example, in this embodiment, a first threshold value and a second threshold value for a screening test for infants are set in advance. For example, the first threshold value for myopia is set to -2.00D. Also, for example, the second threshold value for hyperopia is set to +2.00D. Therefore, for example, if the screening value of the subject's eye falls within the allowable range from -2.00D to +2.00D, the control unit 80 determines that the subject's eye has no refractive error. Also, for example, if the screening value of the subject's eye does not fall within the allowable range from -2.00D to +2.00D, the control unit 80 determines that the subject's eye has a refractive error.

[0085] Furthermore, for example, when the control unit 80 determines that the eye to be examined has a refractive error, it determines whether the screening value of the eye to be examined exceeds the first threshold value or the second threshold value. For example, when the screening value of the eye to be examined has a negative sign, it determines that the screening value exceeds the first threshold value (-2.00D) set in the negative direction with 0.00D as a reference. For example, the control unit 80 determines that the eye to be examined is suspected of being myopic. Also, for example, when the screening value of the eye to be examined has a positive sign, it determines that the screening value exceeds the second threshold value (+2.00D) set in the positive direction with 0.00D as a reference. For example, the control unit 80 determines that the eye to be examined is suspected of being hyperopic. Note that the examiner may be able to arbitrarily change the settings of such first and second threshold values. For example, the result of the determination of refractive error by the control unit 80 is stored in the memory 82.

[0086] First, the left eye will be described. For example, the screening value of the left eye is a first spherical refractive power of −1.50 D, which corresponds to a negative reading. For example, the control unit 80 compares this screening value with a predetermined threshold value (allowable range of ±2.00 D). As an example, it may be possible to determine whether the screening value is equal to or lower than the upper limit of the allowable range and equal to or higher than the lower limit of the allowable range. For example, in this case, since the screening value of the left eye falls within the allowable range, it is determined that the left eye has no refractive error.

[0087] Next, the right eye will be described. For example, the screening value of the right eye is a first spherical refractive power of -2.50D corresponding to a positive reading. For example, the control unit 80 compares the screening value with a predetermined threshold (allowable range of ±2.00D) in the same manner as the left eye. For example, here, the screening value of the right eye does not fall within the allowable range, and it is determined that the right eye has a refractive error. Furthermore, since the screening value of the right eye has a negative sign, it is determined that it exceeds the first threshold (-2.00D), and the right eye is determined to be suspected of being myopic.

[0088] <Output of the eye refractive power of the test eye and screening results> For example, the control unit 80 outputs the measurement result of the eye refractive power acquired by the photorefraction method measurement of the eye to be examined and the screening result based on the judgment result of the refractive error of the eye to be examined. For example, in this embodiment, it is preset to output the second eye refractive power of the first eye refractive power and the second eye refractive power as the measurement result of the eye refractive power of the eye to be examined. Therefore, for example, as the measurement result of the eye refractive power of the eye to be examined, the second cylindrical refractive power represented by a minus sign, the second spherical refractive power corresponding to the second cylindrical refractive power, and the second astigmatic axis angle are output. Also, for example, in this embodiment, the measurement result of the eye refractive power of the eye to be examined and the screening result are displayed on the display 11. For example, the screening result of the eye to be examined is displayed as a message encouraging the eye to be examined for a detailed examination.

[0089] Fig. 6 is an example of a display screen 100 of the display 11. Fig. 6(a) is an initial screen displayed when the subject's eye is suspected of being myopic. Fig. 6(b) is a screen displayed when the display format of the measurement results of the eye refractive power is changed by operating an S.MAX display button 103 described later. For example, the display screen 100 displays a screening result 101 of the subject's eye, a measurement result 102 of the eye refractive power of the subject's eye, an S.MAX display button 103, an alert mark 104, and the like.

[0090] For example, the screening result 101 is a message displayed based on the result of the judgment of the refractive error of the subject eye. As an example, if at least one of the left and right eyes has a refractive error, "COMPLETE EYE EXAM RECOMMENDED" is displayed. As another example, if neither the left nor right eye has a refractive error, "SCREENING COMPLETE" is displayed. Note that the content of the message is not limited to this, and it is sufficient if the content allows the examiner to understand whether the subject eye has a refractive error or not. In this embodiment, the left eye is judged to have no refractive error, and the right eye is judged to be suspected of being myopic, so the screening result 101 is "COMPLETE EYE EXAM RECOMMENDED".

[0091] For example, the measurement result 102 is a measurement result of the eye refractive power of the subject eye. For example, the measurement result 102 displays the second eye refractive power including the second cylindrical power with a minus sign. In this embodiment, the second spherical refractive power of -1.00D, the second cylindrical refractive power of -0.50D, and the second cylindrical axis angle of 90°, which are the second eye refractive powers of the left eye, are displayed. In addition, the second spherical refractive power of -1.00D, the second cylindrical refractive power of -1.50D, and the second cylindrical axis angle of 90°, which are the second eye refractive powers of the right eye, are displayed.

[0092] For example, the S.MAX display button 103 is a button for displaying, as the measurement result 102, an eye refractive power including a spherical refractive power (first spherical refractive power or second spherical refractive power) having the maximum absolute value among the first eye refractive power and the second eye refractive power in the measurement result of the eye refractive power of the examinee's eye. For example, the S.MAX display button 103 displays, as the measurement result 102, an eye refractive power including a spherical refractive power having the maximum absolute value, regardless of the setting of the ophthalmic apparatus 1 to display the second eye refractive power as the measurement result (in other words, regardless of the setting of the cylindrical refractive power sign to be preferentially displayed).

[0093] The alert mark 104 is a mark indicating that the screening value (i.e., the first or second spherical refractive power with the maximum absolute value) used to determine the refractive error of the subject's eye does not fall within a predetermined threshold. For example, in this embodiment, when the screening value of the subject's eye exceeds either the first threshold, which is a criterion for determining myopia, or the second threshold, which is a criterion for determining hyperopia, the alert mark 104 is displayed on the S.MAX display button 103. For example, the alert mark 104 may be displayed as an asterisk. Of course, the content of the alert mark is not limited to this, and may be any content that allows the examiner to understand whether the subject's eye has a refractive error.

[0094] For example, in this embodiment, when the measurement of the eye refractive power of the subject eye and the judgment of the refractive error are completed, the control unit 80 displays the screen shown in Fig. 6(a) on the display 11. For example, in this embodiment, the second eye refractive power corresponding to the negative reading of the subject eye is displayed as the measurement result 102, but the message of the screening result 101 is selected based on the absolute value of the spherical refractive power (first spherical refractive power and second spherical refractive power) corresponding to the cylindrical refractive power of both the negative reading and the positive reading, so that the possibility of overlooking the refractive error of the subject eye is extremely low. Therefore, for example, the examiner can easily determine whether or not the subject eye has a refractive error by checking the message of the screening result 101.

[0095] For example, when the examiner checks the measurement result 102 to check the degree of refractive error of the subject eye, whether the refractive error is in the left or right eye, etc., it may be difficult to grasp the details because the second spherical refractive power of the left eye, −1.00 D, and the second spherical refractive power of the right eye, −1.00 D, do not exceed the allowable range of ±2.00 D. For this reason, in this embodiment, the examiner can press the S.MAX display button 103 to switch the display of the measurement result 102 to the display of the measurement result based on the spherical refractive power with the maximum absolute value.

[0096] For example, the control unit 80 may change the screen displayed on the display 11 from the screen illustrated in FIG. 6(a) to the screen illustrated in FIG. 6(b) based on an operation signal from the S.MAX display button 103. For example, in the measurement result 102 in FIG. 6(b), the first spherical refractive power of −2.50D selected as the screening value for the right eye, the first cylindrical refractive power of +1.50D corresponding to the first spherical refractive power, and the first cylindrical axis angle of 180° are displayed. More specifically, for example, the measurement result 102 in FIG. 6(b) switches from the display of the second eye refractive power corresponding to a negative reading to the display of the first eye refractive power corresponding to a positive reading. In addition, an alert mark 104 is displayed for the first spherical refractive power. This allows the examiner to easily determine that the first spherical refractive power of the left eye, −1.50D, is within the allowable range of ±2.00D and that there is no refractive error in the left eye. In addition, the examiner can easily determine that the first spherical refractive power of the right eye, −2.50 D, is not within the allowable range of ±2.00 D and that the right eye has a refractive error (here, the right eye is suspected of being myopic).

[0097] In the above, the display screen 100 in the case where the left eye of the subject has no refractive error and the right eye is suspected of being myopic has been taken as an example, but the display screen 100 in the case where neither the left nor right eye of the subject has any refractive error will also be described. Fig. 7 is an example of the display screen 100 in the case where the subject has no refractive error. Note that the screening result 101, the measurement result 102, the S.MAX display button 103, the alert mark 104, etc. in Fig. 7 are the same as those in the display screen 100 in Fig. 6, and therefore detailed description thereof will be omitted.

[0098] For example, when the measurement of the ocular refractive power of the subject eye and the judgment of the refractive error are completed, the control unit 80 causes the display 11 to display the measurement results stored in the memory 82 and the screening results based on the judgment result of the refractive error. For example, since the screening result of the subject eye shows that there is no refractive error in either the left or right eye, the message "SCREENING COMPLETE" is displayed. For example, the examiner can easily determine from the message of the screening result 101 that there is no refractive error in either the left or right eye.

[0099] As described above, for example, the ophthalmic apparatus of the present embodiment includes an acquisition means for acquiring at least spherical refractive power and cylindrical refractive power as the ocular refractive power of the test eye, which acquires a first cylindrical refractive power with a positive sign and a first spherical refractive power corresponding to the first cylindrical refractive power, and acquires a second cylindrical refractive power with a negative sign and a second spherical refractive power corresponding to the second cylindrical refractive power, a determination means for determining refractive error based on the spherical refractive power with the largest absolute value among the first spherical refractive power and the second spherical refractive power, and a predetermined threshold value that is a criterion for determining refractive error for the test eye, and a control means for outputting the determination result by the determination means. For example, the ocular refractive power of the test eye can be expressed in two ways: a positive reading in which the cylindrical refractive power is represented by a positive sign, and a negative reading in which the cylindrical refractive power is represented by a negative sign. The spherical refractive power corresponding to the cylindrical refractive power changes depending on whether the cylindrical refractive power is read by a positive reading or a negative reading. Therefore, for example, in one cylindrical power reading, the spherical power does not exceed the standard for determining refractive error, but in the other cylindrical power reading, the spherical power may exceed the standard for determining refractive error. For example, in such a case, the refractive error of the subject eye may be overlooked, and the examiner cannot easily determine the refractive error. However, for example, in this embodiment, the spherical power with the maximum absolute value among the spherical powers according to each cylindrical power reading is used to determine the refractive error, so that the refractive error can be easily determined. As a result, the overlooking of the refractive error of the subject eye can be reduced.

[0100] Also, for example, in the ophthalmic device of the present embodiment, the control means outputs the eye refractive power of the subject eye together with the judgment result, and includes a setting means for setting whether to output the first cylindrical refractive power with a positive sign or the second cylindrical refractive power with a negative sign as the cylindrical refractive power of the eye refractive power of the subject eye, and when the judgment means judges that the spherical refractive power with the maximum absolute value is less than a predetermined threshold, the control means outputs the cylindrical refractive power with the sign set by the setting means and the spherical refractive power corresponding to the cylindrical refractive power with the sign set by the setting means as the eye refractive power, and when the judgment means judges that the spherical refractive power with the maximum absolute value is equal to or greater than a predetermined threshold, the control means outputs the spherical refractive power with the maximum absolute value and the cylindrical refractive power corresponding to the spherical refractive power with the maximum absolute value as the eye refractive power, regardless of the sign set by the setting means. For example, in the ophthalmic device, when the eye refractive power of the subject eye is output, the cylindrical refractive power may be set to be output as either a positive reading or a negative reading. For example, in this case, the cylindrical refractive power of the eye to be examined is outputted in a reading based on the setting, so it may be difficult to grasp whether the spherical refractive power corresponding to this cylindrical refractive power exceeds the standard for determining refractive error.Therefore, for example, in this embodiment, among the spherical refractive powers corresponding to the positive reading and the negative reading of the cylindrical refractive power, when the spherical refractive power with the maximum absolute value exceeds the standard, the eye refractive power of the eye to be examined is outputted in the reading of the cylindrical refractive power that obtains the spherical refractive power with the maximum absolute value.This allows the examiner to easily determine the refractive error of the eye to be examined.

[0101] For example, the ophthalmic device of the present embodiment includes a measuring means for objectively measuring the ocular refractive power of the subject's eye by a photorefraction method, the measuring means having a plurality of measurement light sources arranged in the meridian direction with respect to the optical axis center, a light projecting optical system for irradiating the measurement light emitted from the plurality of measurement light sources onto the fundus of the subject's eye, and a light receiving optical system for detecting the reflected light of the measurement light reflected by the fundus of the subject's eye with a detector, and the acquiring means acquires at least the spherical refractive power and the cylindrical refractive power based on the measurement result by the measuring means. For example, the measurement by the photorefraction method may be used for screening examinations for amblyopia for infants such as 3-year-olds. For example, amblyopia in infants is easily improved by starting treatment early, and early detection by screening examinations is necessary. Therefore, for example, even if the ophthalmic device is an apparatus that performs measurements using the photorefraction method, the possibility of overlooking a refractive error of the examined eye (particularly amblyopia in this case) can be reduced by using the spherical refractive power with the largest absolute value among the spherical refractive powers corresponding to the positive and negative readings of the cylindrical refractive power to determine the refractive error.

[0102] <Example of transformation> In the ophthalmologic apparatus of the present embodiment, the refractive error of the subject eye is determined by determining whether the screening value of the subject eye falls within an allowable range from the first threshold value to the second threshold value, but the present invention is not limited thereto. For example, the refractive error of the subject eye may be determined by determining whether the screening value of the subject eye exceeds the first threshold value of myopia or exceeds the second threshold value of hyperopia. For example, in this case, the determination of which threshold value is to be exceeded may be determined depending on whether the screening value of the subject eye has a minus sign or a plus sign. As an example, when the screening value of the subject eye has a minus sign, only the determination of whether the screening value of the subject eye has a first threshold value of myopia or exceeds the second threshold value may be performed. Also, as an example, when the screening value of the subject eye has a plus sign, only the determination of whether the screening value of the subject eye has a second threshold value of hyperopia or exceeds the first threshold value may be performed. Of course, both the determination of whether the screening value of the subject eye has a minus sign or a plus sign and the determination of whether the screening value of the subject eye has a second threshold value may be performed.

[0103] In the ophthalmic device of the present embodiment, a screening value (i.e., the first spherical refractive power or the second spherical refractive power with the maximum absolute value) for determining the refractive error of the eye to be examined is obtained by comparing the first spherical refractive power when the cylindrical refractive power is expressed in a negative reading and the second spherical refractive power when the cylindrical refractive power is expressed in a positive reading from the eye refractive power of the eye to be examined, but the present embodiment is not limited to this. For example, either the first spherical refractive power or the second spherical refractive power may be obtained as the screening value based on the sign of the equivalent spherical refractive power of the eye to be examined.

[0104] For example, when the spherical equivalent power of the subject's eye is positive, the second spherical power corresponding to the second cylindrical power with a negative sign may be obtained as the screening value. Also, when the spherical equivalent power of the subject's eye is negative, the first spherical power corresponding to the first cylindrical power with a positive sign may be obtained as the screening value.

[0105] As an example, when the first refractive power of the subject eye is acquired as a first spherical refractive power of +1.00D, a first cylindrical refractive power of +1.50D, and a first cylindrical axis angle of 90°, and the second refractive power of the subject eye is acquired as a second spherical refractive power of +2.50D, a first cylindrical refractive power of -1.50D, and a first cylindrical axis angle of 180°, the equivalent spherical refractive power (SE) is calculated as +1.75D for both the first refractive power and the second refractive power. For example, since the equivalent spherical refractive power has a positive sign, the control unit 80 may acquire the second spherical refractive power of +2.50D corresponding to the second cylindrical refractive power with a negative sign as a screening value. For example, by changing the selection of the first spherical power and the second spherical power in accordance with the sign of the equivalent spherical power in this manner, it is possible to obtain the spherical power with the maximum absolute value.

[0106] In the ophthalmologic apparatus of the present embodiment, as a screening value for determining the refractive error of the subject's eye, either the first or second spherical refractive power with the maximum absolute value is acquired, and the refractive error is determined based on whether or not the first or second spherical refractive power exceeds a predetermined threshold value. However, the present invention is not limited to this. For example, the refractive error may be determined by comparing both the first and second spherical refractive powers with a predetermined threshold value. That is, both the first and second spherical refractive powers may be used as screening values ​​for determining the refractive error. For example, in this case, the control unit 80 may compare both the first and second spherical refractive powers with a predetermined threshold value, and determine that there is a refractive error when at least one of the first and second spherical refractive powers exceeds the predetermined threshold value.

[0107] In the ophthalmologic apparatus of the present embodiment, the measurement result 102 on the display screen 100 (see FIG. 6) is preset to display the second eye refractive power including the second cylinder refractive power in a negative reading, but the present invention is not limited to this. For example, the measurement result 102 may be preset to display the first eye refractive power including the first cylinder refractive power in a positive reading. Also, the measurement result 102 may be preset to display the first eye refractive power including the first cylinder refractive power in a positive reading, so that the examiner can change the setting to display either the first eye refractive power or the second eye refractive power at will.

[0108] In the ophthalmic apparatus of the present embodiment, the ocular refractive power including the spherical refractive power (first spherical refractive power or second spherical refractive power) with the maximum absolute value is displayed as the measurement result 102 by pressing the S.MAX display button 103 on the display screen 100 (see FIG. 6 ). However, the present invention is not limited to this. For example, the ophthalmic apparatus may be configured to change which of the first and second refractive powers of the subject eye is displayed as the measurement result 102 based on the result of the refractive error of the subject eye. For example, when the ophthalmic apparatus 1 is set to display the second refractive power corresponding to a negative reading, if the refractive error of the subject eye is not determined, the measurement result 102 may be displayed as the second refractive power. When the refractive error of the subject eye is determined, the measurement result 102 may be displayed as the ocular refractive power including the screening value used for the judgment of the refractive error. Of course, the measurement result 102 may be displayed in advance with both the values ​​of the first and second refractive powers.

[0109] In the ophthalmologic apparatus of the present embodiment, when the examinee's eye has a refractive error, a message is displayed as the screening result 102 and an alert mark 104 is displayed to notify the examiner of the presence or absence of a refractive error. However, the present invention is not limited to this. For example, instead of the message or the alert mark, the apparatus may be configured to execute any of the following controls: color inversion or blinking of the spherical refractive power displayed in the measurement result 102, display of a symbol other than an asterisk, etc. Also, for example, the apparatus may be configured to execute control such as generation of sound or vibration, blinking of a lamp, etc., in addition to displaying the message or the alert mark.

[0110] In the ophthalmic device 1 of the present embodiment, the refractive error is determined by comparing the spherical refractive power (here, a screening value) having the maximum absolute value among the first spherical refractive power corresponding to the first cylindrical refractive power with a plus sign and the second spherical refractive power corresponding to the second cylindrical refractive power with a minus sign with a predetermined threshold value, and the eye refractive power of the subject eye and the screening result are displayed on the display 11. However, the present embodiment is not limited to this. For example, the ophthalmic device 1 may acquire the first spherical refractive power and the second spherical refractive power, and display the spherical refractive power having the maximum absolute value among them on the display 11. In other words, the comparison process between the screening value for determining the refractive error of the subject eye and a predetermined threshold value may not necessarily be performed. Of course, for example, the ophthalmic device 1 may output the cylindrical refractive power, the astigmatism axis angle, the equivalent spherical refractive power, etc. corresponding to the spherical refractive power having the maximum absolute value.

[0111] For example, when the spherical refractive power with a non-maximum absolute value is displayed, the spherical refractive power with a non-maximum absolute value does not exceed the criterion for determining refractive error, but the spherical refractive power with a maximum absolute value may exceed the criterion for determining refractive error, so that the refractive error of the subject eye may be overlooked. However, for example, when the spherical refractive power with a maximum absolute value is displayed, the spherical refractive power as the value farthest from 0.00D is displayed in advance, so that the examiner can easily determine whether or not the criterion for determining refractive error is exceeded by checking the display 11. Therefore, for example, even an examiner with little knowledge is less likely to overlook the refractive error of the subject eye.

[0112] In this way, for example, the ophthalmic device of the present embodiment includes an acquisition means for acquiring at least spherical refractive power and cylindrical refractive power as the ocular refractive power of the test eye, which acquires a first cylindrical refractive power with a positive sign and a first spherical refractive power corresponding to the first cylindrical refractive power, and acquires a second cylindrical refractive power with a negative sign and a second spherical refractive power corresponding to the second cylindrical refractive power, and a control means for outputting the ocular refractive power of the test eye, which outputs the spherical refractive power with the maximum absolute value among the first spherical refractive power and the second spherical refractive power. For example, the examiner can easily determine whether the test eye has a refractive error by checking the spherical refractive power with the maximum absolute value.

[0113] In this embodiment, the ophthalmic apparatus 1 is described as an apparatus that objectively measures the ocular refractive power of the subject's eye by a photorefraction method, but is not limited thereto. For example, the ophthalmic apparatus may be an apparatus that objectively measures the ocular refractive power of the subject's eye by a method other than the photorefraction method. Also, for example, the ophthalmic apparatus may be a subjective ophthalmic examination apparatus that subjectively measures the ocular refractive power of the subject's eye.

[0114] For example, the subjective optometry device may have a correction optical system arranged in the optical path of a light projection optical system that projects a visual target light beam toward the subject's eye, changes the optical characteristics of the visual target light beam, and includes a subjective measuring means that subjectively measures the optical characteristics of the subject's eye. As an example, the correction optical system may be an eye examination unit (phoropter) that switches and arranges optical elements arranged in front of the subject's eye. As another example, the correction optical system may be configured to change the optical characteristics of the visual target light beam by controlling an optical element arranged between an optical member for guiding the visual target light beam toward the subject's eye and a visual target presenting unit for presenting a visual target to the subject's eye. That is, the correction optical system may be a phantom lens refractometer (phantom correction optical system). [Explanation of symbols]

[0115] 1 Ophthalmology equipment 2. Cabinet 3 Presentation window 10. Projection optical system 11 Display 13 Measurement light source 14 Base 20 Light receiving optical system 21 Detector 25 Receiving objective optical system 26 Objective Lens 40 Projection optical system 100 display screens

Claims

1. An ophthalmic apparatus for objectively measuring the ocular refractive power of a subject's eye, comprising: an acquisition means for acquiring at least a spherical refractive power and a cylindrical refractive power as the ocular refractive power of the subject's eye, the acquisition means acquiring a first cylindrical refractive power with a positive sign and a first spherical refractive power corresponding to the first cylindrical refractive power, and acquiring a second cylindrical refractive power with a negative sign and a second spherical refractive power corresponding to the second cylindrical refractive power; a determination means for determining the refractive error based on the spherical refractive power having the largest absolute value among the first spherical refractive power and the second spherical refractive power, and a predetermined threshold value that is a determination criterion for the refractive error of the eye to be examined; a control means for outputting a determination result by the determination means; An ophthalmic apparatus comprising:

2. The ophthalmic apparatus of claim 1, the control means outputs the ocular refractive power of the subject's eye together with the determination result, a setting unit for setting whether to output the first cylindrical refractive power having a plus sign or the second cylindrical refractive power having a minus sign as the cylindrical refractive power of the eye refractive power of the subject's eye, The control means When the determining means determines that the spherical refractive power with the maximum absolute value is less than the predetermined threshold, the cylindrical refractive power with the sign set by the setting means and the spherical refractive power corresponding to the cylindrical refractive power with the sign set by the setting means are output as the ocular refractive power, When the determining means determines that the spherical refractive power at which the absolute value is maximum is equal to or greater than the predetermined threshold value, the ophthalmic device outputs, as the eye refractive power, the spherical refractive power at which the absolute value is maximum and the cylindrical refractive power corresponding to the spherical refractive power at which the absolute value is maximum, regardless of the sign set by the setting means.

3. 3. The ophthalmic apparatus according to claim 1, a measuring means for objectively measuring the ocular refractive power of the subject's eye by a photorefraction method, The measuring means a projection optical system having a plurality of measurement light sources arranged in a meridian direction with respect to the center of an optical axis, and irradiating the measurement light emitted from the plurality of measurement light sources onto the fundus of the subject's eye; a light receiving optical system that detects reflected light of the measurement light reflected by the fundus of the subject's eye with a detector; and The ophthalmic apparatus according to claim 1, wherein the acquisition means acquires at least the spherical refractive power and the cylindrical refractive power based on the measurement results obtained by the measurement means.

4. An ophthalmic apparatus for objectively measuring the ocular refractive power of a subject's eye, comprising: an acquisition means for acquiring at least a spherical refractive power and a cylindrical refractive power as the ocular refractive power of the subject's eye, the acquisition means acquiring a first cylindrical refractive power with a positive sign and a first spherical refractive power corresponding to the first cylindrical refractive power, and acquiring a second cylindrical refractive power with a negative sign and a second spherical refractive power corresponding to the second cylindrical refractive power; a control means for outputting the ocular refractive power of the subject's eye, the control means outputting the spherical refractive power having the largest absolute value among the first spherical refractive power and the second spherical refractive power; An ophthalmic apparatus comprising:

5. 1. An ophthalmology program comprising: an acquiring step of acquiring at least spherical refractive power and cylindrical refractive power as ocular refractive power of the subject's eye, the acquiring step including acquiring a first cylindrical refractive power with a positive sign and a first spherical refractive power corresponding to the first cylindrical refractive power, and acquiring a second cylindrical refractive power with a negative sign and a second spherical refractive power corresponding to the second cylindrical refractive power; a determination step of determining the refractive error based on the spherical refractive power having the largest absolute value among the first spherical refractive power and the second spherical refractive power, and a predetermined threshold value that is a determination criterion for determining the refractive error of the eye to be examined; a control step of outputting a determination result obtained by the determination step; An ophthalmology program characterized by causing a processor to execute the above.

6. 1. An ophthalmology program comprising: an acquiring step of acquiring at least spherical refractive power and cylindrical refractive power as ocular refractive power of the subject's eye, the acquiring step including acquiring a first cylindrical refractive power with a positive sign and a first spherical refractive power corresponding to the first cylindrical refractive power, and acquiring a second cylindrical refractive power with a negative sign and a second spherical refractive power corresponding to the second cylindrical refractive power; a control step of outputting the eye refractive power of the subject's eye, the control step outputting the spherical refractive power having the largest absolute value among the first spherical refractive power and the second spherical refractive power; An ophthalmology program characterized by causing a processor to execute the above.

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