JP3015042B2 - Hand-held eye refractometer - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a hand-held eye refractometer used, for example, in an ophthalmic clinic.

[Related Art] In a conventional hand-held eye refractometer, in order to more accurately measure the refractive power of the eye to be examined, it is necessary to accurately position the hand-held eye refractometer with respect to the eye to be examined.

[Problems to be Solved by the Invention] However, since it is difficult to perform stable alignment of a hand-held eye refractometer as compared with a stationary eye refractometer, skill is required to perform accurate refractive power measurement. is needed.

SUMMARY OF THE INVENTION An object of the present invention is to provide a hand-held eye refractometer capable of improving operability, in particular, enabling an unskilled examiner to check the alignment state of the apparatus with respect to the subject's eye and more accurately perform eye refraction measurement. To provide.

Means for Solving the Problems In a hand-held eye refractometer according to the present invention for achieving the above object, a light beam is projected onto a fundus of a subject's eye, and reflected light is photoelectrically detected to measure eye refraction. A measurement system, a detection system for photoelectrically detecting the subject's eye for alignment of the subject's eye, a display member integrally provided in a main body including the measurement system and the detection system, and a display member for displaying a detection result of the detection system; And a contact member provided integrally with the section and in contact with the face of the eye to be examined.

[Operation] The hand-held eye refractometer having the above-described configuration can easily perform the measurement while holding the main body portion by hand with respect to the subject's eye while viewing the display of the face of the subject's eye contacting the contact member and the display member. In addition, the eye can be positioned with respect to the subject's eye, and the eye refraction can be accurately measured.

[Example] The present invention will be described in detail based on an illustrated example.

FIG. 1 shows a configuration diagram in which a hand-held eye refractometer according to a first embodiment is brought into contact with a face of a subject, and a housing-shaped device main body 1 is shown.
Is provided with a protruding portion 2 to be brought into contact with the face of the subject S. On the optical path P1 from the measurement light source 3 inside the apparatus main body 1 for alignment and refraction value measurement to the subject's eye E, a lens 4 is arranged in order from the measurement light source 3 side, and a central aperture
A central aperture stop 5 having 5a, a perforated mirror 6, a light splitting mirror 7, a lens 8, and a dichroic mirror 9 are provided.

On the optical axis P2 in the direction in which the reflected light from the eye E is reflected by the light splitting mirror 7, there are five sensor elements 10a to 10e as shown in FIG.
Sensor 10 in which sensor elements 10b to 10e are arranged around
Is provided. As shown in FIG. 4, five LEDs 11a to 11e to which outputs of the sensor elements 10a to 10e are connected are mounted outside the apparatus main body 1 so that the examiner can observe them.

On the optical axis P3 in the direction in which the reflected light from the eye E is reflected by the perforated mirror 6, the apertures 12a to 12a are provided as shown in FIG.
A 6-hole aperture 12 having 2f, a lens 13, a separation prism 14 composed of six wedge prisms 14a to 14f, and a photoelectric sensor 15 are arranged as shown in FIG. A fixation target 16 is provided behind the dichroic mirror 9 on the extension of the optical path connecting the subject's eye E and the dichroic mirror 9. The dichroic mirror 9 has a property of reflecting near-infrared light used for alignment and measurement, and transmitting visible light irradiated on the fixation target 16. Reference numeral 17 denotes a control unit. The outputs of the photoelectric sensors 10 and 15 are connected to the control unit 17, and the output of the control unit 17 is connected to the measurement light source 3.

At the time of refraction value measurement, the examiner holds the device body 1,
The projection 2 is brought into contact with the face below the subject's eye of the subject S so that the optical axis P4 coincides with the optical axis of one eye of the subject's eye E, and the subject is examined while viewing the subject's eye E through the dichroic mirror 9. Person S
The fixation target 16 is fixed through the dichroic mirror 9.

The luminous flux from the measurement light source 3 is a lens 4, a central aperture stop 5,
After passing through the perforated mirror 6, the light splitting mirror 7, and the lens 8, the light is reflected by the dichroic mirror 9 in the direction of the eye E to reach the eye E, and the luminous flux from the corneal reflection image returns along the same optical path. The light beam reflected by 7 is projected on the photoelectric sensor 10. Further, the fundus reflection light reflected by the fundus Er passes through a light splitting mirror 7, a perforated mirror 6, a 6-hole aperture 12, and a lens 13, and is deflected by a separation prism 14 in a direction to be separated from the optical axis P3. Thereafter, as shown in FIG. 7, six fundus reflection lights are projected on the photoelectric sensor 15.

During alignment, the sensor elements 10a to 1 of the photoelectric sensor 10
When a light amount equal to or greater than a predetermined threshold value is received at 0e, the corresponding LEDs 11a to 11e connected to the received sensor elements 10a to 10e are turned on.
It is set so that the LEDs 11a to 11e are turned on when the amount of light incident on .about.10e is large. When the corneal reflected light beam is received by the sensor element 10a at the center of the photoelectric sensor 10,
It is detected that the alignment has been completed.

When the alignment is performed, the measurement light source 3 is turned on by a command from the control unit 17, and it takes several tens of milliseconds until the fundus reflection light beam for measuring the refraction value is received on the photoelectric sensor 15. Since the subject S fixes his / her eyes on the distant fixation target 16, there is no need to guide the adjustment of the subject's eye E when the alignment is completed and the refraction value measurement is started.

In addition, although a refraction value measuring method is conceivable other than the above-described embodiment, in the above-described embodiment, information of each meridian is simultaneously captured and the measurement is performed with high accuracy because it is not affected by the movement of the eye E. The protruding portion 2 is in contact with the face below the eye E of the subject S because the difference between races is smaller below the eye E than above the eye E.

FIG. 8 shows a configuration diagram of the inside of the apparatus main body of the second embodiment,
A dichroic mirror 18 is provided instead of the light splitting mirror 7 on the optical path P1 in FIG. 1, and the optical axis P2 in the direction reflected by the dichroic mirror 18 includes a lens 19 composed of a concave lens and two wedge prisms. Separation prism 20,
A mirror 21 is provided, and a dichroic mirror 22 for guiding a light beam reflected by the mirror 21 to the photoelectric sensor 15 is provided on the optical axis P3. An alignment light source 23 for alignment is provided near the lens 8 and away from the optical path P1, and the wavelength of the light beam from this alignment light source 23 is different from the wavelength of the light beam from the measurement light source 3. Thus, the dichroic mirror 18 and the dichroic mirror 22 can distinguish these wavelengths.

The light beam from the positioning light source 23 is reflected by the dichroic mirror 9 and reaches the eye E, and the cornea reflected light beam returns along the same optical path and passes through the lens 8 to the dichroic mirror 18.
And is reflected from the optical axis P2 by the separation prism 20 through the lens 19, further reflected by the mirror 21 and the dichroic mirror 22, and reflected on the photoelectric sensor 15 by the anterior segment of the eye E as shown in FIG. The image E 'and the corneal reflection image Ec' are received.

The luminous flux from the measurement light source 3 at the time of refraction value measurement reaches the fundus of the eye E through the lens 4, the center aperture stop 5, the perforated mirror 6, the dichroic mirror 18, the lens 8, and the dichroic mirror 9, and the fundus reflected luminous flux Returns to the same optical path P1 and is reflected by the perforated mirror 6 to form a 6-hole aperture 12, a lens 1
3. The light passes through the dichroic mirror 22 through the separation prism 14 and is received by the photoelectric sensor 15.

When the separating prism 20 is not used, the anterior ocular segment reflected image E 'is received on the photoelectric sensor 15, so that it may be displayed on a liquid crystal display device or the like for alignment. Since the corneal reflection image Ec 'has a particularly large amount of light, a threshold value can be set to detect the position of the corneal reflection image Ec'. The positional deviation in the optical axis direction is detected from the interval between these two corneal reflection images Ec ', and the positional deviation in a plane perpendicular to the optical axis is detected from the position of the corneal reflection image Ec'. Perform positioning. Once this alignment has been made, refraction measurement is performed as in the previous embodiment.

[Effects of the Invention] As described above, in the hand-held eye refractometer according to the present invention, the position of the main body with respect to the subject's eye can be easily adjusted while viewing the display on the face of the subject's eye and the display member, and the eye refraction can be measured. Can be performed accurately.

[Brief description of the drawings]

Drawings show an embodiment of a hand-held eye refractometer according to the present invention, FIG. 1 is a configuration diagram of the first embodiment, FIG. 2 is a front view of a central aperture stop, FIG. 3 is a front view of a photoelectric sensor, FIG. 4 is a front view of a monitor, FIG. 5 is a front view of a 6-hole aperture, FIG. 6 is a front view of a separation prism, FIG. 7 is an explanatory view of a fundus reflection image on a photoelectric sensor, and FIG. FIG. 9 is a configuration diagram of the second embodiment, and FIG. 9 is an explanatory diagram of a reflected image on the photoelectric sensor. Reference numeral 1 denotes an apparatus main body, 3 denotes a measurement light source, 6 denotes a perforated mirror,
Reference numerals 9, 18, and 22 denote dichroic mirrors, 10, 15 photoelectric sensors, 11 denotes LEDs, 16 denotes a fixation target, 17 denotes a control unit, and 23 denotes a positioning light source.

Claims (3)

(57) [Claims] A measuring system for projecting a light beam onto the fundus of the eye to be examined and photoelectrically detecting the reflected light to measure the refraction of the eye; a detection system for photoelectrically detecting the eye to be examined for positioning the eye; A display member provided integrally with the main body including the system and the detection system to display a detection result of the detection system; and a contact member provided integrally with the main body and abutting on the face of the eye to be examined. Handheld eye refractometer. 2. The hand-held eye refractometer according to claim 1, wherein said display member comprises a plurality of LEDs. 3. The hand-held eye refractometer according to claim 1, wherein said detection system detects corneal reflected light of the eye to be examined.