JPH0612729Y2 - Optometry device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to an optometry apparatus having a mechanism for objectively measuring the refractive power of the eye and a mechanism for subjectively measuring the refractive power of the eye.

[Prior Art] As an apparatus for measuring the refractive power of the eye for preparing spectacles, the objective method is used because of the fact that the measurement time is short, no skill is required for the measurement, and therefore the difference in measurement by the examiner is small. Automatic refractometers are widely used. Some devices have a subjective measuring function and can measure both the subjective and the subjective with a single device.

As such a material, Japanese Patent Application Laid-Open No. Sho 5 (1998)
The device disclosed in 9-80227 is known.

However, the above publication does not mention how to specify the objective measurement value input at the time of subjective measurement. Therefore, the most appropriate value among the measurement results of the objective measurement is not always input during the subjective measurement, and the subjective measurement is not always started in the corrected state based on the input.

[Object of the Invention] An object of the present invention is to solve the above-mentioned drawbacks of the prior art, and to provide a device that can shift to subjective measurement based on a highly accurate objective measurement value and that is simpler in operation. .

[Summary of the Invention] In order to achieve the above object, an optometry apparatus of the present invention receives a light beam of a measurement target projected on a fundus of an eye to be inspected by a light detecting element, and the refractive power of the eye to be inspected according to the detection result. In an optometry apparatus equipped with a measuring device for measuring the eye, an optotype presenting means for presenting an optotype for subjective measurement, a refractive power correction optical system for correcting the refractive power of an eye to be examined, and the refractive power correction optical system. Driving means, a storage means for storing the measured value by the measuring device, a judging means for judging whether or not a desired number of times of measurement has been performed, and a measured value stored by the storing means. And a control means for issuing a signal for operating the driving means to execute correction based on the representative value by a processing completion signal of the processing means.

Further, the control means of the above invention is characterized by issuing a control signal for alternately switching the driving means between a state in which the refractive power of the eye to be inspected is corrected and an uncorrected state.

[Embodiment] Hereinafter, details of the present invention will be described with reference to the drawings of an embodiment.

FIG. 1 is a basic layout of the optical system of the optometry apparatus according to the present invention.

Reference numeral 1 is a measurement light source having a wavelength in the infrared region, 2 and 3 are condenser lenses, and 4 is a movable spot diaphragm (measurement target, hereinafter simply referred to as a measurement target) so as to be arranged at a position conjugate with the fundus of the eye 8 to be inspected. 5 and 6 are objective lenses, 7 and 9 are prisms, 10 are mirrors, 11 and 12 are relay lenses, 13
Is a strip-shaped corneal reflection removal mask arranged at a position conjugate with the cornea of the eye 8 to be inspected, 14 is a moving lens that moves together with the spot diaphragm 4, and 15 is an imaging lens. 16
Denotes a light receiving element for measurement, which is adapted to rotate about the optical axis in synchronization with the light source for measurement 1 and the corneal reflection removal mask 13.

Reference numeral 17 denotes a first relay lens that can move on the optical axis, and the amount of movement thereof is proportional to the spherical refractive power of the subject's eye. 18, 1
Reference numeral 9 denotes a positive cylindrical lens having an equal focal length, both of which are independently rotatable about the optical axis in the same direction or opposite directions about the optical axis. It should be noted that when a cylindrical component is created by two cylindrical lenses, it is necessary to take the spherical effect into consideration for correction.

20 is a second relay lens, 21 is a second relay lens 20
In the optotype plate arranged at the focal position of, even if the fixation target and the target for subjective measurement are arranged on one optotype plate,
It may be a rotating disk-shaped object in which targets are arranged at intervals in the circumferential direction. It may also have a plurality of rotating disks. 22
Is a condenser lens, and 23 is an illumination lamp that illuminates the visual target.

FIGS. 2 and 3 show another embodiment of the target optical system, in which 18a and 19a in FIG. 2 are positive cylindrical lenses having the same focal length. It is rotatable about an axis.

In FIG. 3, 18b is a positive cylindrical lens, which is movable on the optical axis. Reference numeral 19b denotes a negative cylindrical lens, which rotates together with the positive cylindrical lens 18b on the optical axis.

Furthermore, both of these cylindrical lenses and the first relay lens are movable on the optical axis.

FIG. 4 is a block diagram showing a path for actuating the first relay lens 17 and the cylindrical lenses 18, 19 in the target optical system, and 24 is a dial provided on the side part of the body (not shown) for indicating the rotary encoder. A pulse signal is generated by rotation.

25 is a pulse counter, 26 is a microcomputer for controlling all operations related to objective and subjective measurement, 27 is a display, 28 is a pulse motor driver, 29 is a cylindrical lens 18, 19 rotated around the optical axis, A pulse motor for changing the surface refractive power and the axial angle, 30 is a D / A converter for converting a digital signal into an analog signal, and 31 is for moving the first relay lens 17 along the optical axis to change the spherical refractive power. Is a DC motor, and 32 is an A / D converter.

The configuration is as described above, and its operation will be described below with reference to the flowchart of FIG.

When the device is turned on, the conventional data is cleared and set to the initial state (step 100). After the alignment with respect to the eye 8 to be inspected is completed, when a measurement button (not shown) is pressed (step 101), the measurement light beam emitted from the light source 1 passes through the condenser lenses 2 and 3, the spot diaphragm 4, and the objective lens 5, and then the object to be measured. The light is focused on the cornea of the optometry 8 and reaches the fundus. On the other hand, the light from the illumination lamp 23 passes through the condenser lens 22 and projects the optotype plate 21 onto the fundus of the eye 8 to be inspected.
Fixate on.

The light flux reflected by the fundus of the eye is reflected by the mirror 10, passes through the relay lenses 11 and 12, and then is imaged on the light receiving element 16 by the imaging lens 15. The light beam incident on the light receiving element 16 is D / A converted and then supplied to the microcomputer 26 as a digital signal.

The microcomputer 26 sets the spot diaphragm 4 until the position of the spot diaphragm 4 reaches a position conjugate with the fundus of the eye 8 to be inspected.
And the moving lens 14 is moved. At the same time, the optotype plate 21 forms an image on the fundus of the eye 8 to be inspected, and then the first relay lens 17 is moved so that cloud is applied by an appropriate diopter.

After that, the measurement light source 1, the corneal reflection removal mask 13 and the measurement light receiving element 16 are rotated by 180 ° around the optical axis. During rotation, the spot diaphragm 4 and the moving lens 14 move according to the signal from the light receiving element, and the amount of movement allows the value of the refractive power for each radial line to be known (step 102).

The objective measurement as described above is performed, and the microcomputer 26 counts the number of times of measurement. When a certain preset number of times is reached (either by pressing the measurement button each time or continuously by pressing the measurement button once until the specified number of times is reached, the measurement error should not be counted in the number of times. The higher the reliability is, the more the representative value is automatically calculated (steps 103 and 104).

The calculation of the representative value is performed by applying various statistical methods. That is, a method in which an average value of SPH values (or SE values), CYL values, and AXIS values is used as a representative value, a method in which an intermediate value is used as a representative value, and the like can be considered. Further, in adopting these methods, methods such as canceling the maximum and minimum values and canceling abnormal values can be used together.

When the representative value is calculated in this manner, the first relay lens 17 automatically moves in the optical axis direction to the position corresponding to the representative value under the control of the microcomputer 26, and the cylindrical lenses 18 and 19 move the optical axis. Rotate independently in the center (step 105).

The specified number of times of measurement to shift to the subjective measurement can be determined in advance, or can be switched by a target optical system selector switch (not shown) or the like.

Unlike the present embodiment, the prescribed condition for automatically shifting from the objective measurement to the subjective measurement is not the number of times of measurement, but may be another condition such as the stability of the measured value or a combination thereof.

Therefore, the subject's eye 8 sees the optotype on the optotype plate 21 in a state where the refractive power obtained by the objective measurement is corrected, that is, in the corrected state. If the target for subjective measurement is placed on a target plate separate from the target for fixation for objective measurement, the target for automatic measurement is automatically switched. In this state, if the subject cannot visually recognize the Landolt's ring corresponding to a visual acuity of 1.0, for example, the subjective measurement can be performed, and if it is unnecessary, it can be stopped (steps 106 and 107). .

After that, when a target optical system changeover switch (not shown) is pressed, the first relay lens 17 moves to a position where the eye 8 can be seen with the naked eye 8 and the cylindrical lenses 18 and 19 rotate, respectively. To do. When the target optical system changeover switch (not shown) is pressed again, the setting of the target optical system returns to the above-mentioned correction state (steps 108 and 109). Since this operation is performed instantaneously, the subject can easily compare the appearances of the corrected state and the naked eye state.

Also, while wearing glasses or contact lenses, objective measurement, or if the spherical refractive power of the front spectacles, the cylindrical surface refractive power and the axial angle is input in advance, the correction state by the target optical system switching function, It is possible to compare appearances in a plurality of states such as the front glasses state and the naked eye state.

Further, the optotype optical system may be changed over not by a switch or the like, but by a method of automatically changing over every fixed time.

[Effect of the Invention] As apparent from the above description, according to the configuration of the present invention,
After objective measurement of the eye to be inspected, without any operation of the inspector, since the driving power is arranged to correct the refractive error of the eye to be inspected, the refractive power correction optical system is based on the highly reliable measurement value.
You can smoothly shift to subjective measurement. Further, by reducing the operational burden on the examiner, the examiner can concentrate on the optometry.

[Brief description of drawings]

FIG. 1 is a basic layout diagram of an optical system of an optometry apparatus according to the present invention,
2 and 3 are optical layout diagrams showing another embodiment of the target optical system, FIG. 4 is a basic block diagram of the electric system, and FIG. 5 is a flow chart diagram. FIG. 5 is a flowchart of the embodiment. 1 ... Measurement light source, 4 ... Spot diaphragm 5, 6 ... Objective lens 8 ... Eye to be inspected, 13 ... Corneal reflection removal mask 14 ... Moving lens, 16 ... Light receiving element 17 ... First relay lens 18, 19 …… Cylindrical lens 21 …… Target

Claims (2)

[Scope of utility model registration request] 1. An optometry apparatus comprising a measuring device for receiving a light flux of a measurement target projected on a fundus of an eye to be inspected by a photodetector and measuring the refractive power of the eye to be inspected by the detection result. Index presenting means for presenting the optotype, a refractive power correction optical system for correcting the refractive power of the eye to be inspected, a driving means for driving the refractive power correction optical system, and a measurement value stored by the measuring device. Storing means, judging means for judging whether or not the desired number of times of measurement has been performed, processing means for processing the measured values stored by the storing means to obtain a representative value, and processing of the processing means An optometry apparatus comprising: a control unit that outputs a signal for operating the drive unit to execute correction based on a representative value by a completion signal. 2. The optometry apparatus according to claim 1, wherein the control means issues a control signal for alternately switching the driving means between a state in which the refractive power of the eye to be inspected is corrected and an uncorrected state.