JP6057061B2 - Eye refractive power measuring device - Google Patents

Description

  The present invention relates to an eye refractive power measuring apparatus that measures the eye refractive power of a subject's eye.

  Visual acuity measurement of the visual target in the state where the visual target of the visual target presenting optical system is presented at the required near distance, and the addition is added to the corrected state for the distance by the drive control of the correction optical system. 2. Description of the Related Art A subjective eye refractive power measurement apparatus capable of performing the above is known (for example, see Patent Documents 1 and 2). In the subjective eye refractive power measurement device according to the description of Patent Document 1, addition power set in advance according to the age of the subject is automatically added at the start of near vision measurement, and the addition power measurement is efficiently performed. It is possible to do.

  In addition, in the objective eye refractive power measuring apparatus according to the description in Patent Document 2, how much addition is required based on the spherical power obtained by the distance and near objective eye refractive power measurement. It is possible to calculate and measure the addition efficiently.

JP 2010-110388 JP 2004-129711 A

  However, since the participation varies depending on the individual, even if the initial value of the addition is set for each age, there is a possibility that the difference from the actual addition is not small. Further, when measuring the refractive power of the near eye, it is difficult to measure in a state where the accommodation power of the eye to be examined is reliably applied. For this reason, the measurement result may be obtained in a state where the adjusting force is not working, or in order to avoid this, the measurement is performed a plurality of times, and thus the measurement may take time. That is, there is an insufficient point in the method of setting the initial value of the addition based on the spherical power obtained by the distance measurement and the near distance measurement.

  An object of the present invention is to provide an ocular refractive power measuring device capable of smoothly measuring the addition power in view of the above-described problems of the prior art.

  In order to solve the above problems, the present invention is characterized by having the following configuration.

(1) An eye refractive power measuring device for measuring the eye refractive power of an eye to be examined,
A correction optical system that is arranged between the eyesight test target and the eye to be examined and corrects the spherical refractive power of the eye of the subject;
Addition power estimation means for estimating an initial value of the addition power of the eye to be examined;
Control means for driving the correction optical system and adding an addition corresponding to the initial value estimated by the addition estimation means ;
The addition degree estimation means is obtained by presenting the distance vision of the eye to be examined obtained by presenting the eyesight test target from a distance and the eyesight test target from a near distance. When the difference from the near vision of the eye to be examined is large, the initial value is estimated to be larger than when the difference is small .

  According to the present invention, it is possible to perform near vision measurement with added power in a short time.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an external configuration diagram of an objective eye refractive power measurement apparatus according to this embodiment. The objective eye refracting power measuring apparatus 100 moves to the base 1, the face support unit 2 attached to the base 1, the moving base 3 movably provided on the base 1, and the moving base 3. The measuring unit 4 is provided so as to accommodate an optical system described later. The measuring unit 4 is moved in the left-right direction (X direction), the up-down direction (Y direction), and the front-rear direction (Z direction) with respect to the subject eye E by the driving unit 6 provided on the moving table 3. The movable table 3 is moved on the base 1 in the left-right direction and the front-rear direction by operating the joystick 5. Further, the measurement unit 4 is moved in the vertical direction by the drive of the drive unit 6 by the rotation operation of the rotary knob 5a. On the top of the joystick 5, a measurement start switch 5b is provided. A display monitor 7 is provided on the movable table 3.

  FIG. 2 is a schematic configuration diagram of an optical system and a control system of the apparatus. The eye refractive power measurement optical system 10 includes a projection optical system 10a that projects a spot-like measurement index on the fundus oculi Ef through the center of the pupil of the subject eye E, and fundus reflection light reflected from the fundus oculi Ef. And a light receiving optical system 10b that picks up a ring-shaped fundus reflection image on the imaging element of the two-dimensional light receiving element.

  The projection optical system 10 a includes a measurement light source 11, a relay lens 12, a hall mirror 13, and a measurement objective lens 14 disposed on the optical axis L <b> 1 of the measurement optical system 10. The measurement light source 11 is arranged in a positional relationship optically conjugate with the fundus oculi Ef of the normal eye. The opening of the Hall mirror 13 is optically conjugate with the pupil of the subject's eye E.

  In the light receiving optical system 10b, the objective lens 14 and the hall mirror 13 of the projection optical system 10a are shared, and the relay lens 16 and the total reflection mirror 17 disposed on the optical axis L1 in the reflection direction of the hall mirror 13, and the total reflection mirror. 17 includes a light receiving stop 18, a collimator lens 19, a ring lens 20, and an imaging element 22 that is a two-dimensional light receiving element. The light receiving diaphragm 18 and the image sensor 22 are disposed in a positional relationship optically conjugate with the fundus oculi Ef. The ring lens 20 includes a lens portion in which a cylindrical lens is formed in a ring shape on a transparent flat plate, and a light shielding portion where light is shielded except for the ring-shaped lens portion. The ring lens 20 is optically conjugate with the pupil of the eye E through an optical system from the objective lens 14 to the collimator lens 19. An output from the image sensor 22 is input to the control unit 70. Further, the measurement light source 11 of the projection optical system 10a, the collimator lens 19, the ring lens 20, and the image sensor 22 of the light receiving optical system 10b are integrally moved by the moving mechanism 23 in the optical axis direction. As the eye refractive power measuring optical system 10, a well-known one can be used.

  Between the objective lens 14 and the subject eye E, the target luminous flux from the target presentation optical system 30 is guided to the subject eye E, and the reflected light from the anterior eye part of the subject eye E is observed. A dichroic mirror 29 leading to the optical system 50 is disposed. The dichroic mirror 29 transmits the wavelength of the measurement light beam used in the measurement optical system 10.

  An alignment index projection optical system 40 is disposed in front of the anterior segment of the subject's eye E. The alignment index projection optical system 40 includes a ring index projection optical system 41 that projects a ring index on the cornea of the subject's eye E, an index projection optical system 42 that projects an infinite index of two bright spots on the cornea Ec, Is provided. The index projection optical system 42 is arranged symmetrically with respect to the observation optical axis. The ring index projection optical system 41 is also used as anterior segment illumination that illuminates the anterior segment of the subject's eye E.

  The observation optical system 50 includes an imaging lens 51 and a two-dimensional imaging element 52 arranged on the optical axis in the reflection direction of the half mirror 53. An output from the image sensor 52 is input to the control unit 70. As a result, the anterior segment image of the subject's eye E is captured by the two-dimensional image sensor 52 and displayed on the monitor 7. The observation optical system 50 also serves as an optical system that detects an alignment index image formed on the cornea of the eye E by the alignment index projection optical system 40, and is in an alignment state based on the position detection of the alignment index image by the control unit 70. The suitability is determined.

  The optotype presenting optical system 30 shares the objective lens 39 of the observation optical system 50, and includes a light source 31 such as an LED disposed on the optical axis L <b> 2 coaxial with the optical axis L <b> 1 by the dichroic mirror 29, and a target plate 32. , Relay lens 33 and reflecting mirror 36. The optotype presenting optical system 30 is shared with the refractive power correcting optical system for correcting the refractive power of the subject's eye, and the astigmatism correcting optical system 34 is disposed between the reflecting mirror 36 and the relay lens 33. ing.

  The target plate 32 has a plurality of targets 32a including a fixation target for performing clouding on the subject's eye E during objective refractive power measurement and a visual test for visual acuity used during subjective refractive power measurement. They are arranged on concentric circles. As the visual acuity test target, visual targets for each visual acuity value (visual acuity values 0.1, 0.3,..., 1.5) are prepared. The optotype plate 32 is rotated by a motor 37, and the optotype 32a is switched and disposed on the optical axis L2 of the optotype presenting optical system 30. The target luminous flux of the target 32a illuminated by the light source 31 travels toward the subject's eye E via an optical member from the relay lens 33 to the dichroic mirror 29.

  The light source 31 and the target plate 32 (target 32a) are integrally moved in the direction of the optical axis L2 by a drive mechanism 38 including a motor and a slide mechanism. By moving the light source 31 and the target 32a, the target display position (presentation distance) is optically changed from the distance to the near distance. As a result, cloud is applied to the subject eye E during objective refractive power measurement, and the spherical refractive power of the subject's eye is corrected during subjective refractive power measurement. That is, a correction optical system having a spherical power is configured by the movement of the objective lens 39, the relay lens 33, the light source 31, and the target 32a. The correction optical system having a spherical power may be configured by adding a relay lens that can move in the optical axis direction to the visual target presenting optical system.

  The astigmatism correction optical system 34 includes two positive cylindrical lenses 34a and 34b having the same focal length. The cylindrical lenses 34a and 34b are independently rotated about the optical axis L2 by driving the rotation mechanisms 35a and 35b, respectively. The correction optical system may have a configuration in which the correction lens is taken in and out of the optical path of the optotype presenting optical system.

  The control unit 70 is connected to the image sensor 22 and performs a refractive power calculation process based on the output of the image sensor 22. The control unit 70 includes an image sensor 52, a moving mechanism 23, a driving mechanism 38, a motor 37, a light source 31, rotating mechanisms 35a and 35b, a display monitor 7, a switch unit 80 used for various settings, a measurement start switch 5b, and an image. The memory 75, the drive unit 6, the printer 90, and the like are connected.

  FIG. 3 is an explanatory diagram of the switch configuration of the switch unit 80 and the display on the monitor 7. The screen of the monitor 7 in FIG. 3 is an example of the subjective visual acuity measurement screen 200. In the switch unit 80, eight switches 80a to 80h are arranged. The function of each switch signal is switched in accordance with the screen of the monitor 7 that is switched by selecting the measurement mode.

  Next, the measurement operation of the apparatus having the above configuration will be described. When the device is activated, it is set to the objective power measurement mode for distance use. In this case, as the visual target 32a of the visual target presenting optical system 30, a fixation target (for example, a landscape visual target) for applying cloud fog is set in the optical path. The examiner fixes the subject's face to the face support unit 2, and a fixation target arranged in the measurement unit 4 via the measurement window 4 a (see FIG. 1) of the measurement unit 4 is applied to the subject's eyes. Let me fix it.

  When measuring objective refractive power, the anterior segment of the subject's eye E is imaged by the imaging element 52 of the observation optical system 50, and an anterior segment image is displayed on the monitor 7. In addition, the ring index image projected by the ring projection optical system 41 and the index image at infinity projected by the index projection optical system 42 are captured by the image sensor 52. These alignment index images are also displayed on the monitor 7. The examiner observes the anterior segment image, alignment target image, and reticle on the monitor 7, moves the measurement unit 4 and the moving table 3 by operating the joystick 5, etc. Are aligned in a predetermined positional relationship. When the measurement start signal is input from the measurement start switch 5b after the alignment is completed, the refractive power is measured.

  When the automatic alignment mode is set by a switch (not shown), the control unit 70 detects the alignment state based on the alignment index image captured by the image sensor 52. The alignment state in the vertical and horizontal directions is detected by the positional relationship between the center position of the ring index image by the ring projection optical system 41 and the optical axis. The alignment state in the working distance direction is detected by utilizing the characteristic that the infinity index by the index projection optical system 42 does not change even if the working distance changes, and the image interval in the predetermined meridian direction of the ring index changes. (See JP-A-6-46999). Based on the detection results of these alignment index images, the drive unit 6 is driven, and the measurement unit 4 is moved so that the alignment state is appropriate. When the alignment is completed, a trigger for a measurement start signal is automatically issued by the control unit 70, and the distance power measurement is performed.

  The measurement light emitted from the light source 11 is projected onto the fundus oculi Ef via the relay lens 12 to the dichroic mirror 29, and forms a spot-like point light source image on the fundus oculi Ef. The light of the point light source image formed on the fundus oculi Ef is reflected and scattered by the fundus occupying the subject eye E, and the optical system up to the objective lens 14, the hall mirror 13, the relay lens 16 and the total reflection mirror 17. Then, the light is condensed again on the aperture of the light receiving diaphragm 18 and is made into a substantially parallel light beam (in the case of a normal eye) by the collimator lens 19. It is taken out as a ring-shaped light beam by the ring lens 20 and received by the image sensor 22 as a ring image.

  In the measurement of the distance objective eye refractive power, first, preliminary measurement of eye refractive power is performed, and the light source 31 and the fixation target plate 32 are moved in the direction of the optical axis L2 based on the result of the preliminary measurement. The cloud E is applied to the eye E. Thereafter, the main measurement of the eye refractive power is performed on the eye to be inspected with fog. In this measurement, a ring image by the ring lens 20 is picked up by the image pickup device 22, and an output signal from the image pickup device 22 is stored in the image memory 75 as image data (measurement image). Thereafter, the control unit 70 performs image analysis on the ring image stored in the image memory 75 to obtain the value of refractive power in each meridian direction. The control unit 70 obtains objective values of S (spherical power), C (astigmatic power), and A (astigmatic axis angle) of the subject's eye during distance use by performing a predetermined process on the refractive power. . The objective value obtained at the time of distance use is stored in the memory 75.

  The eye refractive power measurement optical system 10 is not limited to the configuration using the ring-shaped index image as described above, and projects the measurement index on the fundus, receives the reflected light beam from the fundus with the light receiving element, and at least 3 Any optical system that obtains the refractive power in the meridian direction can be used, and a known one can be used.

  FIG. 4 is a flowchart showing the measurement procedure. When the objective power measurement for distance use is completed and the switch 80a is pressed, the monitor 7 switches to the subjective distance vision measurement (objective power measurement) mode, and the screen of the monitor 7 is the screen of the objective power measurement mode. (Not shown) is switched to the subjective distance vision measurement screen 200 shown in FIG. The control unit 70 drives the correction optical system based on the refractive power (spherical power S, astigmatism power C, astigmatism shaft angle A) of the subject's eye obtained by measuring the objective refractive power for distance use. Correct the refractive error of the human eye. That is, the light source 31 and the target plate 32 are moved in the direction of the optical axis L2 based on the spherical power S in the distance objective refractive power measurement, so that the refractive power error of the spherical refractive power S is corrected. . Further, the astigmatism correction optical system 34 is driven based on the astigmatism power C and the astigmatism axis angle A, and a correction state in which the refractive power error of astigmatism is corrected is obtained. In addition, the control unit 70 rotates the target plate 32 by controlling the rotation of the motor 37, and arranges the required visual acuity value visual target 32a on the optical axis L2 (for example, a visual target having a visual acuity value of 0.8).

  As described above, when the initial presentation target is presented to the subject's eye, the examiner measures the distance vision of the subject. When the switches 80b and 80c corresponding to the UP and DOWN displays 202a and 202b of the visual acuity value are pressed, the visual acuity value target to be presented is switched. If the examinee's answer is correct, the examiner selects the switch 80b to switch to a visual target having a higher visual acuity value. On the other hand, if the subject's answer is an incorrect answer, the switch 80c is selected to switch to a target with a visual acuity value that is one step lower. The control unit 70 rotates the visual target plate 32 based on a signal input for changing the visual acuity value by the switch 80b or 80c, and switches the visual acuity value visual target 32a on the optical axis of the visual target presenting optical system. The examiner obtains the maximum visual acuity that can be read by the subject by repeating the above procedure.

  When the maximum vision value for distance using the correction power of the objective refractive power measurement result is obtained, the examiner adjusts the spherical power (the weakest power) from the most plus that allows the subject to obtain the highest vision value. The spherical power S is changed by operating the switches 80f and 80g corresponding to the UP / DOWN displays 204a and 204b for changing the spherical power in FIG. When the switch 80f or the switch 80e is selected, the light source 31 and the target plate 32 are moved in the direction of the optical axis L2, and the spherical power is changed. As a result, the weakest spherical power S at which the highest visual acuity is obtained is determined, and a reference value for prescribing the distance correction power such as a spectacle lens or a contact lens is obtained.

  Next, the examiner performs near vision measurement by moving the presented visual target to the near distance. When the switch 80h for inputting a signal for shifting to the near vision measurement mode is pressed, a near vision measurement screen is displayed on the monitor 7. FIG. 5 is a display example of the near vision measurement screen 220. In the near vision measurement screen 220, the “ADD” display 221 corresponds to the switch 80d, and a command signal for adding power is added by the switch 80d when the near vision is measured. The visual acuity value UP / DOWN displays 202a and 202b correspond to the switch 80b and the switch 80c. In addition, UP / DOWN displays 224a and 224b for changing the power of addition correspond to the switches 80f and 80g, respectively. The display field 230 on the screen 220 displays the near distance in the near vision measurement. In the display column 231 in the center of the monitor 7, the added power is displayed. In the measurement result display column 240, the correction power values (S, C, A) for distance use are displayed.

  When switched to the near vision measurement mode by the switch 80h, the light source 31 and the target plate 32 are moved on the optical axis L2 by the drive mechanism 38, and the target display distance by the target plate 32 is required. Moved to the near distance. For example, the visual target is set at a position corresponding to a near distance of 33 cm. A near distance of 33 cm corresponds to −3.0 D (diopter) in terms of refractive power. The control unit 70 is as close as 3.0D (diopter) based on the position of the correction power for distance (the correction power for distance determined by the objective refractive power measurement for distance or the visual acuity measurement for distance). The target plate 32 is moved to a position closer to the direction. That is, it is set to a power obtained by adding a spherical power of −3.0D (diopter) to the correction power for distance use. For example, when the distance spherical power of the subject's eye is -2.0D, -3.0D is added to this, and the power at the near distance of 33 cm is -5.0D. It should be noted that when the switch 80h for shifting to the near vision measurement mode is pressed, there is no addition (0.00D). In the near measurement, the astigmatism refraction error is corrected by driving the astigmatism correction optical system based on the result of the distance objective refractive power measurement. Thus, the subject's eye can check the visual target presented at the near distance without being affected by the astigmatic refraction error.

  The examiner measures the near vision of the subject. When the switches 80b and 80c corresponding to the displays 202a and 202b whose visual acuity values are UP and DOWN are pressed, the presented visual acuity value targets are switched. If the examinee's answer is correct, the examiner selects the switch 80b to switch to a visual target having a higher visual acuity value. On the other hand, if the subject's answer is an incorrect answer, the switch 80c is selected to switch to a target with a visual acuity value that is one step lower. The control unit 70 rotates the visual target plate 32 based on a signal input for changing the visual acuity value by the switch 80b or 80c, and switches the visual acuity value visual target 32a on the optical axis of the visual target presenting optical system. The examiner obtains the maximum visual acuity that can be read by the subject by repeating the above procedure.

  The control unit 70 estimates the initial value of the addition based on the distance vision value and the near vision value. For example, it is assumed that the distance vision value is 1.2. At this time, if the near vision is 0.5, the initial value of the addition is set to + 1.0D, and if it is 0.2, the initial value of the addition is set to + 2.0D. . Note that this is an example, and the value used as the initial value of the addition may be a numerical value based on the relationship between the vision value and the addition obtained experimentally, or the distance vision value and the near vision value Based on the above, the examiner may be able to set empirically. Further, the apparatus itself may automatically calculate from the relationship between the visual acuity value and the addition power. Thus, by calculating the initial value of the addition based on the distance vision value and the near vision value, the addition measurement time can be shortened.

  The examiner determines whether the addition is necessary from the result of the near vision measurement. Compared to distance vision, when near vision decreases, or when the subject remarks that the target set at near distance is difficult to see, Move to the visual acuity measurement step. At this time, when the difference between the distance vision value and the near vision value is small, or when the near vision value is a numerical value that is not a problem in life, the eye adjustment lag (the focus position of the original eye is the depth of focus) In consideration of the depth of the image, the control unit 70 considers that there is a possibility that the addition power may not be necessary in consideration of the phenomenon of moving forward or backward within the focus tolerance. You may make it inform. For example, when the near vision is below a certain value (for example, 1.0), a message indicating that the addition is necessary may be displayed on the screen.

  When the switch 80d corresponding to the “ADD” display 221 is pressed, the control unit 70 drives the drive mechanism 38 to add the addition power to the correction optical system (target presentation optical system 30), and the near distance ( The visual target plate 32 is moved in the direction of the optical axis by an amount corresponding to the addition estimated with reference to the position of 40 cm). As a result, in the addition measurement for near use, an appropriate initial value of the addition is easily set, and the measurement time for addition adjustment is shortened. When the addition is added to the target presentation optical system 30, the value of the addition is displayed on the display 231.

  The examiner confirms the appearance of the presentation target in a state where the addition degree is added to the subject. When the subject answers that the target is easy to see, it is determined that the addition is appropriate. When the switches 80f and 80g are pressed, the addition applied to the correction optical system is increased or decreased in 0.25D steps. As a result, the examiner finely adjusts the addition according to the subject's eyes. The adjusted addition value is displayed in the display field 231. When the addition degree can be adjusted, the examiner switches the visual acuity values of the visual targets presented by the switches 80b and 80c, and measures the near visual acuity value at the limit of the subject's eyes.

  In addition, after the addition is adjusted, every time the switch 80d corresponding to the “ADD” display 221 is pressed, the state in which the addition is added to the target-presenting optical system and the state in which the addition is removed are alternately displayed. Is switched to. The state in which the addition power is removed is a state in which the astigmatism power is corrected and the spherical power is corrected based on the visual acuity confirmation measurement in the distance (or the measurement result of the eye refractive power in the distance). Thereby, the subject can compare the difference in the appearance of the near vision target depending on the presence or absence of the addition, and can know the necessity of the addition. For this reason, the examiner can easily explain the necessity of the addition at the near distance to the subject.

  The measurement results of the refractive power of the objective and the measurement results of the refractive power and addition of the subjective are used as reference values for precise subjective measurement. By obtaining the measurement results of these awareness by the objective refractive power measurement device, it becomes easy to determine the prescription value in the precise awareness measurement.

  In addition, in this embodiment, although it was set as the structure which displays the addition added only at the time of adding addition on a display part, it is not limited to this. When it is necessary to add a degree of addition, the degree of addition estimated based on the visual acuity value may be displayed on the display unit in advance. For example, when a visual acuity with a visual acuity of 0.8 is presented during near vision measurement, the addition added to the correction optical system when a button for adding addition is pressed is displayed on the display unit 231 in advance. May be.

  Subsequently, a modification example of the present embodiment will be described with reference to the drawings. FIG. 6 is an external configuration diagram of an optometry system according to a modification example of the present embodiment. The optometry system 500 is roughly divided into an optometry apparatus 350 for subjectively examining the visual function of the subject's eye, an optotype presenting apparatus 330 for presenting a distance test optotype to the subject's eye, It has. The present invention can also be used for such a subjective eye refractive power measurement device that does not have an objective eye refractive power measurement function. A more specific explanation is added below.

  The optometry apparatus 350 includes a pair of left and right symmetric lens chamber units 352 (left lens chamber unit 352L, right lens chamber unit 352R) and a support unit 353 that supports the lens chamber unit 352 in a suspended manner. -It is fixed to the bull 301. In the lens chamber unit 352, a lens disk in which a large number of optical elements such as a spherical lens, a cylindrical lens, a dispersion prism, and a rotary prism are arranged on the same circumference is rotatably held. Optical elements are switched and arranged in the inspection window 351 (left inspection window 351L, right inspection window 351R) provided in 352. Switching of the optical elements arranged in the inspection window 351 is performed by operating a controller 360 that is an input unit (operation unit).

  The support unit 353 includes a distance adjusting mechanism (including a convergence mechanism) of the lens chamber unit 352 for changing the distance between the left examination window 351L and the right examination window 351R in accordance with the distance between the pupils of the subject. In addition, a near bar 420 that slidably holds a near vision target presentation unit 440 is provided at a substantially central portion of the support unit 353 (in the vicinity between the left lens chamber unit 352L and the right lens chamber unit 352R). It is fixed. The optotype presenting unit 440 is moved within a distance of about 20 to 70 cm from the inspection window 351. In the present embodiment, in the near vision value test or the near binocular visual function test, the optotype presenting unit 440 is placed at a position where the distance from the examination window 351 is 40 cm.

  The optotype presenting apparatus 330 includes a display (target presenting unit) 331 that presents a distance test optotype. The optotype presenting apparatus 330 is connected to the controller 360 via the relay unit 306, and the optotype displayed on the display 331 is switched by the operation of the controller 360. The controller 360 is provided with various switches such as a switch for performing a visual acuity value test and a switch for performing a binocular visual function test. The visual target presenting device 330 displays a display in accordance with the operation of the switch. A distance visual acuity test target or a distance binocular visual function test target is displayed (displayed) at 331. The optotype presenting apparatus 330 is positioned at substantially the same height as the optometry apparatus 350 and is installed so as to be separated from the optometry apparatus 350 by a distance suitable for the examination. In the present embodiment, the distance (inspection distance, installation distance) between the optometry apparatus 350 and the optotype presenting apparatus 330 is set to a distance suitable for a distance inspection, for example, 5 m.

  Next, the controller 360 of this embodiment will be described. FIG. 7 is an external view of the controller 360 as viewed from above. The controller 360 includes a display means (output means) and an input means (operation means) for displaying the presented target, examination contents, examination results, and the like. And a switch panel 362 on which a plurality of various switches as input means (operation means) are arranged. The monitor 361 is a color display having a touch panel function, and is configured such that the apparatus can be operated by an examiner selecting (touching) a displayed target, inspection item, and the like. The switch panel 362 has a dial switch 363 for inputting signals such as numerical value increase / decrease, optical element switching, etc. by turning left and right, spherical power S, astigmatism power C, astigmatism axis angle A, interpupillary distance PD, A mode switch 364 for switching to a mode for changing data, a start / feed switch 365 for program inspection, a menu switch 366 for setting or changing a display mode, and the like are provided. For example, in addition measurement, the spherical power of the spherical lens disposed in the inspection window 351 is increased or decreased by rotating the dial switch 363.

  FIG. 8 is a schematic configuration diagram showing an optometry apparatus 350 according to this modification. The lens chamber unit 352 includes a motor 318 that rotates a lens disk, and a motor 319 that rotates a rotating mechanism of a cylindrical lens, a rotating mechanism of a cross cylinder lens, and the like disposed on the lens disk. The technique disclosed in Japanese Patent Application Laid-Open No. 2007-68574 can be used for the rotating mechanism of the cylindrical lens, the rotating mechanism of the cross cylinder lens, and the like.

  The optotype presenting unit 440 includes a case 441 provided with a presenting window 442, an optotype disc 443, and a holder 444 that holds the case 441. A target disc 443 on which a plurality of types of near targets are displayed (printed) is housed in the case 441 so as to be rotatable around a pin 445 at the center of the case 441. A part of the optotype disc 443 is exposed from the case 441. By rotating the optotype disc 443 while holding the exposed portion, the intended near-use target is arranged in the presentation window 442. The holder 444 has a function for attaching the optotype presenting unit 440 to the near bar 420 and supporting the optotype presenting unit 440 so as to be slidable by the near bar 420 (movable in the axial direction of the near bar 420). have. The target presentation unit 440 may be a target plate on which the near target is simply printed, or may be a thin liquid crystal display that displays the near target.

  Next, a control system of the optometry system 500 will be described. FIG. 9 is a schematic block diagram of a control system of the optometry system 500. A control unit 307 that is a control unit of the relay unit 306 includes a control unit 357 that is a control unit of the optometry apparatus 350, a control unit 337 that is a control unit of the optotype presenting apparatus 330, and a control unit 367 that is a control unit of the controller 360. Is connected. The relay unit 306 is a unit for inputting and outputting data, command signals, and the like in the optometry system 500.

  The control unit 337 is connected to a display 331, a memory 338 that is a storage unit that stores a target (data), and the like. The control unit 337 includes a decoder that decodes a command signal transmitted from the controller 360 (control unit 367).

  The control unit 367 is connected to a monitor 361, a switch panel panel 362 including a dial switch 363, and the like, a memory 368 that is a storage unit that stores an inspection program, an inspection result, and the like. In the present embodiment, the controller 360 (control unit 367) controls and controls the entire optometry system 500.

  Command signals (optical element switching command signal, target switching command signal, etc.) from the monitor 361 and the switch panel 362 are sent from the control unit 367 to the control unit 37. The control unit 307 distributes the received command signal to the control unit 357 and the control unit 337. The control unit 357 drives the motors 318, 319 and the like based on the command signal, and arranges the optical element in the inspection window 351. The control unit 337 reads the target (data thereof) from the memory 371 based on the command signal and displays the target on the display 331.

  The addition power measurement using the subjective eye refractive power measuring apparatus having the above configuration will be described. It is common to perform a distance vision test and a near vision test in a refractive correction state after obtaining the complete correction power before measuring the addition. The technique disclosed in Japanese Patent Application Laid-Open No. 11-19041 can be used for an examination procedure, an examination technique, and the like for obtaining the complete correction power of the eye to be examined.

  When performing a distance vision test in a state of refraction correction, the subject is allowed to look into the examination window 351 and a desired target is displayed on the display 331. The examiner asks the subject whether or not the target can be identified, and measures the maximum distance vision value while switching the target appropriately depending on whether the answer is correct or incorrect.

  When performing a near vision test in a state of refraction correction, the subject is allowed to look into the examination window 351, the target presentation unit 440 is moved in front of the examination window 351, and a required near vision target is presented. The examiner asks the subject whether or not the index can be identified, and measures the highest near vision value while switching the index appropriately depending on whether the answer is correct or incorrect.

  When the visual acuity test is completed, it moves to the measurement of the addition power. In the optometry apparatus of this modification example, the initial value of the addition is calculated based on the distance vision value and the near vision value. As a method, for example, when the difference between the distance vision value and the near vision value is large, a large addition is set as an initial value, and conversely, when the difference between the two is small, a small addition is set as an initial value. To do. Note that the method for calculating the initial value of the addition is not limited to this. Thus, by calculating the initial value of the addition, the measurement time of the addition measurement can be shortened as in the embodiment.

  When measuring the addition, the examiner switches the target of the target presentation unit 440 and presents the cross grid chart to the eye to be examined. In addition, when shifting to the addition measurement mode, a ± 0.5D cross cylinder lens is additionally arranged in the inspection window 351. At this time, the minus axis of the cross cylinder lens is set to 90 °. The examiner adjusts the spherical power by the controller 360 while confirming the appearance of the cross grid with the subject. The addition power when the vertical and horizontal lines of the cross grid appear to be equal is the optimum value of the addition power. The addition measurement is not limited to measurement using a cross grid and a cross cylinder.

  When the addition measurement is completed, the near vision test with the addition is performed, and the highest near vision value with the addition is measured.

  In the above description, the initial value of the add power is calculated based on the distance vision value and the near vision value. However, based on only the near vision value, the initial value of the add power is used as the estimated value. It may be calculated. For example, if the initial value of the addition power is switched corresponding to each near vision value, the configuration of the device is simplified.

  Further, the initial value of the addition power may be calculated based on the near vision value and the near eye refractive power value of the eye to be examined acquired in a state where the visual target is presented at the near distance. . Thereby, even if it is a case where an initial value is calculated for addition power using near eye refractive power, the calculation accuracy of an initial value can be improved. In addition, objective addition measurement results are taken into account.

It is an external appearance block diagram of an objective type eye refractive power measuring apparatus. It is a schematic block diagram of the optical system and control system of an apparatus. It is explanatory drawing of the switch structure of a switch part, and the display of a monitor. It is a flowchart which shows a measurement procedure. It is a display example of a near vision measurement screen. It is a schematic block diagram which shows the example of a change of this embodiment. It is an external appearance block diagram of the controller in a modification example. It is a schematic block diagram of the optometry apparatus in a modification example. It is a schematic block diagram of the control system of the optometry system in a modification example.

DESCRIPTION OF SYMBOLS 10 Eye refractive power measurement optical system 10a Projection optical system 10b Receiving optical system 30 Visual target presentation optical system (correction optical system)
70 Control unit 80 Switch unit 100 Objective eye refractive power measurement device 220 Near vision measurement screen 221 “ADD” display 231 display field 250 Target chart display

Claims (1)

An eye refractive power measuring apparatus for measuring the eye refractive power of a subject eye,
A correction optical system that is arranged between the eyesight test target and the eye to be examined and corrects the spherical refractive power of the eye of the subject;
Addition power estimation means for estimating an initial value of the addition power of the eye to be examined;
Control means for driving the correction optical system and adding an addition corresponding to the initial value estimated by the addition estimation means ;
The addition degree estimation means is obtained by presenting the distance vision of the eye to be examined obtained by presenting the eyesight test target from a distance and the eyesight test target from a near distance. An eye refractive power measurement apparatus characterized in that when the difference from near vision of the subject eye is large, the initial value is estimated to be larger than when the difference is small .

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