JP2706248B2 - Eye refractive power measuring device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an eye-refractive-power measuring device that measures the eye refractive power of an eye to be examined.

(Prior art) Some eye refractive power measuring devices that measure eye refractive power share an image receiving element and select a wavelength between a measurement system and an anterior ocular segment observation system using a light splitting material or the like. is there.

(Problems to be Solved by the Invention) In this conventional apparatus, the wavelength of the light of the measurement system is selected by selecting the wavelength of the light of the measurement system and the light of the anterior ocular segment observation system using a light splitting material or the like. And the wavelength of the light of the anterior segment observation system is changed so that the light of the anterior segment observation system does not enter the image receiving element during the measurement of the eye refractive power. If the eye is illuminated and the external light has the same wavelength as the anterior ocular segment illumination light, the anterior ocular segment image leaks into the image receiving element during the measurement, affecting the measurement. There was a disadvantage that it would.

(Object of the Invention) The present invention has been made in view of the above problems, and has as its object to eliminate the influence of external light or the like on the measurement.

(Means for Solving the Problems) In order to achieve the above object, the eye refractive power measuring device according to the present invention cuts the light flux of the anterior ocular segment observation system during the refractive power measurement, so that harmful light for the measurement is removed. This is because a light shielding member is inserted into the anterior ocular segment observation system so as not to enter.

(Operation) In the eye-refractive-power measuring apparatus according to the present invention, even when there is unexpected illumination such as external light, the light of the anterior ocular segment observation system is reliably blocked by the light blocking member, and does not affect the measurement.

(Example) IA. Overall Optical Arrangement FIG. 1 shows an overall optical arrangement of an eye refractive power measuring apparatus according to the present invention. In this eye refractive power measuring apparatus, an objective refractive power measurement system 1 for objectively measuring the refractive power of the eye E, and a fixation of the eye E to fix the visual axis of the eye E during the measurement. A fixation / subjective measurement system 2 for projecting a fixation target to be examined and a target for subjective examination, and a front for performing an anterior segment observation of the eye E to be examined and an alignment between the optical axis of the device and the visual axis of the subject's eye. An eye observation / alignment system 3 is provided.

IB. Objective Refractive Power Measurement System 1 B-1: Pattern Projection System 20 FIG. 2A is an optical path diagram of the pattern projection system 20 shown in FIG. Wavelength 865 nm emitted from light emitting diode 200
Is collected by a condenser lens 201, then refracted by a conical prism 202, and irradiated on a ring pattern 203 for measuring the refractive power. The refractive power measuring light a passing through the ring pattern 203 is transmitted to the relay lens 204 and the mirror 205
(See FIG. 1), ring stop 2 via relay lens 206
Irradiated at 07. After passing through the ring stop 207, the refractive power measurement light a is reflected by the reflection surface 208a of the perforated mirror 208. Thereafter, the refractive power measuring light a is reflected by the mirror 209, passes through the half mirror 112 and 111 as a component of the anterior segment observation and alignment system 3, ring fundus E _R of the eye E by the objective lens 110 Image 203 ′ of pattern 203
(See FIG. 2). Here, the light emitting diode 200 and the ring diaphragm 207 is optically conjugate, and located in an optically conjugate position to the pupil E _P of the ring aperture 207 between the eye E.

B-2: Measurement Optical System 21 FIG. 2 (b) is an optical path diagram of the measurement optical system 21 shown in FIG. Ring pattern image reflected by the fundus E _R of the eye E
The light 203 ′ is collected by the objective lens 110. Then, the light passes through the half mirrors 111 and 112, is reflected by the mirror 209, passes through the opening 208b of the perforated mirror 208, and passes through the stop 210. The refracting power measuring light a passes through the relay lens 211 through the stop 210, is reflected by the half mirror 212 that transmits the visible light b, and is relayed by the relay lens 213 and the mirror 214.
The light is applied to the aperture 215 via the. As shown in FIG. 3, the diaphragm 215 has a peripheral portion 215b through which the refractive power measuring light a having a wavelength of 865 nm is transmitted, and a central portion 21 which cuts the refractive power measuring light a.
5a.

Also, this stop 215 has a range of 400 nm
It has the property of transmitting 0 nm visible light b. Thereby, the refractive power measurement light a passes only through the peripheral portion 215b of the stop 215, and after passing through the half mirror 217 that reflects the visible light b and transmits the refractive power measurement light a via the focusing lens 216, Half mirror 117 of the anterior eye observation / alignment system 3
And is imaged as a ring pattern image 203 ″ (see FIGS. 5 and 6) on the image receiving element 4 by the imaging lens 118.

The focusing lens 216 and the aperture 215 are the light emitting diode 200, the condenser lens 201, and the conical prism of the pattern projection system 20.
202 and the ring pattern 203 are housed together in the movable housing part 219, and are movable in the optical axis direction as indicated by an arrow 218 in FIG.

In the measurement optical system 21 described above, the stop 210 is
A position optically conjugate pupil E _P of the eye E with respect to 10 and the receiver element 4 the eye E is emmetropia (refractive power 0 Diop
ter), the intermediate image plane A of the ring pattern 203 (second
(See the figure).

IC: Fixation and subjective measurement system 2 Visible light b having a wavelength of 400 nm to 700 nm emitted by the light source 30 is condensed by the condenser lens 31 and illuminates the chart plate 32.

For example, a sunburst chart (fixation chart) 32a as a fixation target is provided on the chart plate 32 as shown in FIG.
Visual acuity chart 32b, astigmatism chart 32c, cross cylinder chart 32d, red-green chart 3 for subjective examination
2e are arranged in the circumferential direction, and each chart is selectively inserted into the optical path by being rotated around the axis 34.

The images of the charts 32a to 32e are projected onto the eye E by the projection lens 35, reflected by the mirror 36, reflected by the half mirror 217, and merged into the measuring optical system 21 of the objective refractive power measuring system 1. And passes through a diaphragm 215 via a focusing lens 216, and a half mirror via a mirror 214 and a relay lens 213.
The light is guided to 212, passes through the half mirror 212, and is guided to the variable cross cylinder 37. The visible light b passes through the variable cross ring 37, is reflected by the half mirror 111 via the mirror 38, is projected on the eye E by the objective lens 110, and the charts 32a to 32e are observed by the eye.

A plurality of glare light sources 33 for emitting visible light for a glare test are arranged near the chart plate 32 near the outer periphery of the insertion position of the charts 32a to 32e inserted in the optical path. The light source 33 for the glare test includes the objective lens 11
It can also be placed near zero. Further, instead of providing the light source 33 for performing the glare test, for example, a configuration may be adopted in which the contrast between the visual table of the visual acuity chart 32b and the base is changed.

ID-Anterior Eye Part Observation / Alignment System A plurality of anterior eye part illumination light emitting diodes 40 are arranged outside the objective lens 110, and infrared light having a wavelength of 900 nm emitted from each of the light emitting diodes 40 (hereinafter, referred to as infrared light). , The infrared light is denoted by a symbol d) illuminates the anterior segment of the eye E to be examined. The infrared light (anterior segment illumination light) d reflected by the anterior segment is converged by the objective lens 110, passes through the half mirror 111, and travels along the aforementioned anterior segment observation / alignment system 3. The light is propagated and formed on the image receiving element 4 by the image forming lens 118.

Note that a shutter 114 serving as a shielding member for blocking light from the anterior ocular segment observation / alignment system 3 to the image receiving element 4 during measurement in the optical path of the anterior ocular segment observation / alignment system 3.
Is to be inserted. This may use liquid crystal or the like.

A plurality of light emitting diodes 41 emitting infrared light having a wavelength of 900 nm are arranged near the outer peripheral portion of the objective lens 110, and the plurality of light emitting diodes 41 are an alignment light source. Alignment light emitted from the alignment light source 41 (hereinafter, this alignment light is denoted by reference symbol e) is reflected by the eye E, then condensed by the objective lens 110, and similarly to the anterior segment illumination light d. After passing through the half mirror 111, the light propagates along the anterior ocular segment observation / alignment system 3,
8 forms an image on the image receiving element 4. Note that the light emitting diode 40 for anterior segment illumination may be used instead of the light emitting diode 40 for anterior segment illumination.

In front of the half mirror 115 of the anterior ocular segment observation / alignment system 3, an aiming scale projection optical system is arranged. The standard scale projection optical system includes a light emitting diode 42 that emits red light having a wavelength of 700 nm (hereinafter referred to as scale light).
A condenser lens 43 for condensing the scale light c from the light emitting diode 42, and a scale light c passing through the aiming scale 44.
And a mirror 45 for reflecting the light to join the anterior ocular segment observation / alignment system 3.

The scale light c from the aiming scale 44 is a half mirror
After passing through 115, an image is formed on the image receiving element 4 by the imaging lens 118 via the anterior ocular segment observation / alignment system 3.

II. Electric Circuit Configuration FIG. 4 is a block circuit diagram of the present optometry apparatus. The drive circuit 313 scans the area DDC as the image receiving element 4 in response to a command from the arithmetic and control circuit 301, and outputs the received image as an analog signal.

The arithmetic and control circuit 301 controls the gate circuit 302, and the gate circuit 302 converts an analog signal from the image receiving element 4 into an A / D converter 30.
3 or output to the display interface 304. The display interface 304 receives an analog signal from the image receiving element 4 via the gate circuit 302, and displays an image received by the image receiving element 4 on a display 305 including, for example, a CRT, a liquid crystal television, or a plasma display.

The A / D converter 303 has a function of converting an analog signal from the image receiving element 4 into a digital signal, and the digital signal is input to the arithmetic and control circuit 301.

The arithmetic control circuit 301 is connected to a frame memory 324 that stores data of one screen or data of several screens of the image receiving element converted into a digital signal by the A / D converter 303. The arithmetic control circuit 301 has a function of selectively supplying a pulse from the pulse generator 312 to the driver circuits 318, 319, and 320, counts the number of pulses, and uses the counted value as a signal in the first memory 309. The first memory 309 stores the count value.

The driver circuit 318 supplies the pulse from the arithmetic and control circuit 301 to the pulse motor 321 for driving the movable housing of the refractive power measurement system 1 and drives the pulse motor 321. The driver circuit 319 supplies a pulse to the pulse motor 322 for rotating the chart plate 32 of the fixation / awareness measurement system 2 and the pulse motor 3
Drive 22. The driver circuit 320 supplies a pulse to a pulse motor 323 for rotating the VCC 37, and drives the pulse motor 323.

The arithmetic / control circuit 301 includes driver circuits 314 to 31.
7, 325 to 327 are connected. The driver circuit 315 calculates the power supply to the light emitting diode 200 of the refractive power measurement system 1
This is performed based on a command from the control circuit 301.

The driver circuit 316 includes an anterior ocular segment observation / alignment system 3
The driver circuit 317 to the alignment light source 41, and the driver circuit 325 to the aiming scale light source 42.
In addition, the driver circuits 327 are connected to the glare light sources 33, respectively, and also supply power to these based on instructions from the arithmetic and control circuit 301. The driver circuits 316, 317, 325
Are operated by a common command of the arithmetic and control circuit 301, and the light sources 40, 41, and 42 are configured to turn on and off at the same time. The driver circuit 328 turns on / off the light emitting diode 200 of the refractive power measurement system 1 based on a command from the arithmetic / control circuit 301.
When the light is turned off, the pulse motor 329 is driven, and the shutter 114 is inserted into or removed from the anterior ocular segment observation / alignment system 3. The driver circuit 326 is connected to the light source 30 of the fixation / awareness measurement system 2, and supplies power to the light source 30 based on a command from the control circuit 301.

Further, the arithmetic and control circuit 301 has a second memory for storing a spherical power, a cylindrical power, and a shaft angle based on the measured refractive power.
310 is connected. The measurement of the spherical power, the cylindrical power, and the axis angle based on the refractive power will be described later.

The arithmetic and control circuit 301 includes a program memory 307 storing an arithmetic and control program, and a control switch 308 having various switches for starting measurement and selecting a chart at the time of subjective measurement as shown in FIG. It is connected.

The character circuit 306 that converts the measurement data stored in the memory 310 into characters and numerical values and outputs the converted data to the display interface 304 is also connected to the control circuit 301.

III. Measurement procedure and operation 1) Alignment The examiner turns on the power switch 3081 of the control switch 308.
To ON. Then, the driver circuits 316 and 317 are operated by the operation / control circuit 304, and the light sources 40, 41, 42 and 30 are simultaneously turned on. At the same time, the driving circuit 313 is operated by the arithmetic / control circuit 301, and thereby the image receiving element 4 is scanned. At that time, the arithmetic / control circuit 301 switches the gate circuit 302 so that the analog signal from the image receiving element 4 is transmitted to the display interface 304. Thereby, the anterior segment of the eye E is illuminated with the light d from the light source 40,
The alignment light e from the alignment light source 41 is reflected by the anterior ocular segment, and the light d passes through the anterior ocular segment observation / alignment system 3 onto the image receiving element 4 as an anterior ocular segment image.
Are formed on the image receiving element 4 through the anterior ocular segment observation / alignment system 3 as images of the light source 41 which is an alignment index.

On the other hand, an image of the aiming scale 44 is formed on the image receiving element 4 by the aiming scale light c. These three images are converted into analog signals by the image receiving element 4 and output. The analog signals are input to the display 305 via the display interface 304. As a result, the display 305
Are displayed as an anterior eye image EA, an aim scale image 44 ', and an alignment index image 41' as shown in FIGS. 7 (a) and 7 (b). Note that a spot projection optical system is provided in place of the light source 41 so that the spot projection image is reflected from the corneal vertex, and the spot projection image is formed on the image receiving element 4. A configuration may be adopted in which the pass / fail of the alignment is determined based on whether or not it is within the above-described predetermined range.

The subject visually recognizes the fixation chart 32a illuminated by the light source 30 via the fixation / awareness measurement system 2 which is partially shared with the refractive power measurement system 1. The visual axis of the optometry E is fixed.

When the alignment index image 41 'is outside the aiming scale image 44' as shown in FIG. 7A, the examiner sets the alignment index image 41 'in the aiming scale image 44' (see FIG. 7B). The entire optical system of the apparatus is moved up, down, left and right so that the optical axis of the objective lens 110 coincides with the optical axis of the eye E. Also, the working distance is adjusted to a regular distance by moving the entire apparatus optical system back and forth so that the anterior segment image EA becomes a clear image.

2) Pre-measurement of refractive power When the alignment is completed, the examiner turns on the measurement start switch 3082 of the control switch 308. The arithmetic / control circuit 301 sends the driver circuits 316, 317, 3
The command to 25 is stopped, and the light sources 40, 41, and 42 are turned off for a short time. However, the command to the driver circuit 326 continues,
Light source 30 continues to light. The operation / control circuit 301
During the light-off periods of 0, 41, and 42, an operation command is issued to the driver circuits 314 and 315, and the light source 200 is turned on. Thereafter, until the objective refractive power measurement is completed, the light sources 40, 41, 42 and the light source 200
Is alternately performed. While the light source 200 is on, an operation command is issued to the driver circuit 328 to operate the pulse motor 329, and the shutter 114 is inserted into the anterior ocular segment observation / alignment system 3. When the light source 200 is turned off, the shutter 114
Is a pulse motor 329 according to the operation command of the driver circuit 328.
Is actuated to remove from the anterior ocular segment observation / alignment system 3. Since the anterior segment observation image is not displayed on the display 305 while the light source 200 is on, the display 305 may display, for example, a character display of “under measurement”. Alternatively, a memory area for storing an anterior ocular segment image is provided in the frame memory 324, and the anterior ocular segment image stored in this memory area is displayed on the display 305 during lighting of the light source 200, that is, during measurement. You may make it display.

Light emitting diodes 200 of the objective refractive power measuring system 1 emits a refractive power measuring light a, the ring pattern image on the fundus E _R of the eye E
The light reflected by the fundus of the ring pattern 200 ′ is projected onto the light receiving surface of the image receiving element 4 via the measuring optical system 21.

The arithmetic / control circuit 301 switches the gate circuit 302, and the analog signal from the image receiving element 4 is input to the A / D converter 303.
After that, the arithmetic and control circuit 301 activates the drive circuit 313,
The image receiving element 4 is scanned, and its image output, that is, the image output of the refractive power measurement pattern 203 ″ is output to the A / D converter 303. The A / D converter 303 outputs an analog signal from the image receiving element 4. A /
D-converted and the digital signal is output to the frame memory 324 via the arithmetic / control circuit 301,
24 stores information for one screen.

Arithmetic and control circuit 301, as shown in FIG. 6, the read scanning G _1, G ₂ to a predetermined memory address of the frame memory _{324, ..., G i, ...} , G l, ..., radial accordance G _n And scanning is performed. As a result, data corresponding to the image of the refractive power measurement pattern 203 ″ formed and projected on the image receiving element 4 is read and scanned.

In the case where the eye E to be examined is hyperopic, it is projected outside the image receiving element 4 of the bending force measurement pattern image 203 ″ as shown in Fig. 5. When the eye E to be examined is intense myopia, The pattern image for refractive power measurement is projected small near the center.

In both cases, the arithmetic / control circuit 301 is the driver circuit 3
18 to supply a pulse from the pulse generator 312 to the pulse motor 321 to move the movable housing 219 so that the measurement pattern image 203 ″ is projected within a certain range of the light receiving surface. The focus lens 216 is moved by the movement of the movable housing part 219, but the fixation chart 32a observed by the subject's eye E through the fixation / awareness measurement system 2.
Is designed to be in a cloud fogging state of +1.0 to 2.0 D with respect to the refractive power of the eye E to be examined.

In order to move the moving housing part 219, the pulse motor 3
The number of pulses supplied to 21 is counted by a counting circuit in operation / control circuit 301, and the counted value is stored in first memory 309 as the amount of movement of movable housing 219.

3) Main measurement of objective refracting power The control circuit 301 uses the movable housing 2 based on the above-described pre-measurement.
19 read scanning G ₁ as shown in Figure 6 based on the data in the frame memory 324 based on the captured image by the final receiver element 4 after moving _{the, G 2, ..., G i} , …,
G _l, ..., the point _R g ₁ on power measurement pattern image 203 'by performing _{G n, R g 2, ...} , R g i, ..., obtained _R g _l, ..., the coordinates of _R g _n .

Pattern image for refractive power measurement 20 obtained by read-out scanning
3 "point _R g _{1 of, R g 2, ..., R} g i, ..., R g l, ..., based on the coordinates of _R g _n, ellipse 203 in X _R -Y _R coordinate" formula of Is represented as From equations (1) and (2), S _xR and S _yR
And the refractive power D _{1 of} the strong main meridian and the refractive power D ₂ of the weak main meridian are defined by the radius of the pattern image ▲ ▼ ″ of normal vision (0 Dioptpr).
_{Assuming 0} , in the example shown in FIG. Is required. Here, f is the combined focal length of the measurement optical system 21, and x is the base line length (that is, the radius of the conjugate image of the ring stop at the pupil position of the eye to be examined).

Next, the arithmetic and control circuit 301 determines the amount of movement of the movable housing 219 stored in the first memory 309, that is, the focusing lens 216.
The number of pulses corresponding to the amount of movement of the focusing lens 216 is read out, and from this number of pulses, the refractive power correction d due to the movement of the focusing lens 216 is calculated as the refractive power D ₁ , in addition to D _2, obtaining the _{(D 1 + d), (} D 2 + d). As a result, the spherical refractive power S, cylindrical refractive power C, and cylindrical axis angle θ of the subject's eye are Is required. The arithmetic / control circuit 301 displays the obtained S, C, and θ on the display 305 via the character circuit 306 and the display interface 304, and stores the same in the second memory 310.

4) Subjective Refractive Power Measurement When the examiner next turns on the subjective optometric switch 3083 of the control switch 308, the arithmetic / control circuit 301 drives the driver 31
4, the instruction to 315 is stopped, and thereafter, the light source 200 stops emitting light. Next, when the examiner selects an eyesight test chart with the chart selection switch 3089 of the control switch 308, the arithmetic and control circuit 301 activates the driver circuit 317,
A predetermined number of pulses are supplied from the pulse generator 312 to the pulse motor 322, the chart plate 32 is rotated, and the visual acuity chart 32b (see FIG. 8) is inserted into the optical path of the subjective measurement system 2.

The arithmetic and control circuit 301 calculates the refractive characteristics S 1, C, and θ of the eye E stored in the second memory 310 and the refractive characteristics S _{1 of} the eye E obtained by the objective refractive power measurement, C ₁ and θ are read out, and the focusing lens 21 based on the value of the spherical refractive power S is read out.
The number of pulses required to move 6 is calculated, and the obtained number of pulses is supplied to the pulse motor 321 via the driver circuit 318, and the movable housing section 219 is moved, so that the focusing lens 216 Is performed.

Next, the arithmetic and control circuit 301 calculates the number of pulses for rotating the VCC 37 from the cylindrical refractive power and the axis angle θ, and the obtained number of pulses is supplied to the pulse motor 323 via the driver circuit 320, VCC37 is rotated. As a result, the subjective measurement system 2 performs optical correction in accordance with the refractive power of the eye E obtained by the objective refractive power measurement.

The subject's visual acuity display chart inserted into the subjective measurement system 2
Looking at 32b, answer the direction of the cut of the Landolt ring. The examiner determines the subjective visual acuity of the eye E from the response of the subject, and operates the spherical power correction switch 3088 of the control switch 318 when it determines that the corrected visual acuity is not sufficient. The arithmetic and control circuit 301 responds to the command of the switch 18 by
The pulse from the pulse generator 312 is supplied to the pulse motor 321 via the driver circuit 318, and the focus lens is moved again to a position where the corrected vision is improved. The arithmetic / control circuit 301
The number of pulses at the time of re-movement of the focusing lens is counted, d of Expression (4) is obtained again from the number of pulses, and S ₁ , C ₁ , and θ are calculated by Expression (4) based on the new d. The calculated value is displayed on the display 305.

The examiner then turns on the astigmatism chart 3 with the control switch 308.
When 085 is selected, a predetermined number of pulses are supplied to the pulse motor 322 via the driver circuit 319, the chart plate 32 is rotated, and the astigmatism chart 32c is inserted into the circuit of the subjective measurement system 2. The examinee E looks at the inserted astigmatism chart 32c and answers whether or not there is a line that looks dark. When the examinee responds “yes”, the examiner E switches the cylinder axis correction switch 3090 of the control switch 318. Operate.

The arithmetic / control circuit 301 supplies a pulse to the pulse motor 323 via the driver circuit 320 based on the command,
Rotate C37 to correct the cylinder axis. Arithmetic / control circuit 301
Counts the number of pulses at this time, the cylinder axis angle θ is corrected based on the counted value, and the corrected cylinder axis angle is displayed on the display 305.

Next, when the examiner selects the cross cylinder chart 3086 of the control switch 308, the control circuit 301 controls the pulse motor 323 to set the cylindrical axis C of the VCC 37 to, for example, ± 0.5D with respect to the currently set cylindrical power C. The angle difference is made alternately, the difference in the appearance of the chart 32d at that time is made to be answered, and the examiner operates the cylindrical power correction switch 3089 of the control switch 308 when there is a difference in the appearance, and the arithmetic and control circuit 301 The VCC 37 is controlled based on the command, the cylindrical power is corrected, and a new cylindrical power is displayed on the display 305.

Next, when the examiner selects the red-green chart 3087 of the control switch 308, the control circuit 301 operates the pulse motor 322, and the red-green chart 32e is inserted into the subjective measurement system 2. The examinee answers the appearance of the red-green chart 32e, and the examiner operates the spherical power correction switch 3088 of the control switch 308 according to the response. The arithmetic / control circuit 301 receives the command and operates the pulse motor 321 to move the focusing lens 216, so that the spherical power S is corrected and the new spherical power is displayed on the display 305.
Will be displayed.

5) Glare test The examiner then performed glare test 3 on control switch 308.
Select 091. Then, the arithmetic / control circuit 301 operates the pulse motor 322 via the driver circuit 319, the chart board 32 is rotated, and the visual acuity display chart 32b is displayed on the subjective measurement system 2.
At the same time, the driver circuit 327 is operated, and the glare light source 33 emits light.

The subject looks at the visual acuity display chart 32b in the glare under the glare light source emission. The examiner can know whether or not the subject's eye E has a mild cataract based on the subject's response. The glare light source may be provided with a known volume or the like so that the brightness can be changed.

(Effects of the Invention) As described above, according to the present invention, the eye to be inspected and the like are illuminated by external light or the like to block light from the anterior ocular segment observation and alignment system during refractive power measurement, Does not affect measurement results.

[Brief description of the drawings]

FIG. 1 is a diagram showing the overall optical arrangement of an optometry apparatus according to the present invention, FIG. 2 is an optical path diagram of an objective refractive power measurement system, and FIG.
FIG. 4 is a block diagram showing the configuration of the electric circuit, FIG. 5 is a diagram showing the relationship between the image receiving element and the pattern image, and FIG. 6 explains the principle of measuring the eye refractive power from the pattern system. 7 (a) and 7 (b) are diagrams showing the display state of the display, FIG. 8 is a diagram showing an example of a chart for subjective measurement, and FIG. 9 is a diagram showing a control switch. It is a figure showing switch arrangement. DESCRIPTION OF SYMBOLS 1 ... Objective refractive power measurement system, 2 ... Fixation and subjective measurement system 3 ... Anterior eye observation and alignment system, 4 ... Image receiving element

Claims (1)

(57) [Claims] 1. An eye refractive power measuring apparatus that shares an image receiving element of a measurement system and an anterior eye observation system, wherein the anterior eye part is configured to block a light beam of the anterior eye observation system during refractive power measurement. An eye-refractive-power measuring device, wherein a light-blocking member is provided in an observation system.