JP2783618B2 - Eye refractive power measuring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an eye-refractive-power measuring device used in a optician or an ophthalmic clinic.

[Prior Art] Conventionally, it is known that the same area sensor is used for both anterior ocular segment observation and eye refractive power measurement. In this case, the optical axes of the two are almost matched on the area sensor using a dichroic mirror. At the time of alignment, the anterior segment is projected onto the area sensor using the anterior segment illumination. At the time of measurement, the anterior segment illumination is turned off and the fundus reflection light is projected onto the area sensor.

This conventional example will be described in more detail with reference to FIGS. 3, 4 and 5. FIG.

FIG. 3 shows the entire optical system, and a dichroic mirror
1 and 3 completely transmit the anterior segment illumination light 14 and the refractive power measurement light 10
Is completely reflected. Illumination light during alignment
14 is turned on, and the eye E is projected onto the area sensor 4 through the dichroic mirrors 1 and 3 lens 2. FIG. 4 shows the projected image at this time. At the time of refractive power measurement, the illumination light 14 is turned off, and the measurement light 10 is changed to the relay lens 9, the aperture 8, the perforated mirror 7, the reflection mirror 6, the lens 5, and the dichroic mirror 1.
Through the eye E to be examined.

Then, the fundus reflection light Er of the subject's eye E is converted into a dichroic mirror 1, a lens 5, a reflection mirror 6, a hole mirror 7, and an aperture.
The light is projected on the area sensor 4 via the lens 11, the lens 12, the prism 13, and the dichroic mirror 3. The projected image at this time is shown in FIG. An operation is performed based on the projected image to determine the refractive power.

[Problem to be Solved by the Invention] In a conventional ophthalmologic apparatus, there is also known a method of detecting a corneal reflected light of an eye to be inspected and detecting a relative positional shift between the eye and the apparatus.

Therefore, an object of the present invention is to provide an apparatus which can realize simplification of the apparatus by using such a member including a relative position shift detection system without reducing the accuracy of the relative position shift detection.

[Means for Solving the Problems] The present invention for achieving the above object provides an anterior ocular segment observation optical system for an eye to be examined, and a measurement for projecting measurement light to the fundus of an eye to be examined for objective eye refractive power measurement. A light projection system, a relative position shift detection light projection system for projecting relative position shift detection light onto the cornea of the eye for detection of a relative position shift with the eye to be inspected, and The same area sensor receives the observation light, the fundus reflection light of the measurement light, and the corneal reflection light of the relative position shift detection light, and the central position of the area sensor detects the relative position shift. An eye-refractive-power measuring apparatus characterized in that it is configured to receive corneal reflected light of light and fundus reflected light of the measurement light in a peripheral region.

Example An example of the present invention will be described below with reference to the drawings.

1 and 2 are explanatory views of an embodiment of the present invention. The same reference numerals as those in FIG. 3 indicate the same members. FIG. 1 shows the entire optical system, and the light splitters 1 'and 3'
Is transmitted completely (or partially transmitted), while the eye refractive power measurement light is reflected but slightly transmitted (it may be about 1%). At the time of alignment, the anterior segment illumination light 14 is turned on, and the eye E is projected onto the area sensor 4 through the light splitters 1 'and 3' and the lens 2. At the time of measuring the eye refractive power, the illumination light 14 is turned off, and the light from the measurement light source 10 is transmitted to the relay lens 9, the aperture 8, the perforated mirror 7, the reflection mirror 6,
The light enters the eye E via the lens 5 and the light splitter 1 ′. The light reflected by the fundus Er of the eye E is split into a light splitter 1 ', a lens 5, a reflection mirror 6, a perforated mirror 7, and a stop.
The light is projected onto the area sensor 4 via the lens 11, the lens 12, the prism 13, and the light splitter 3 '.

By the way, at the time of measurement, the light splitters 1 'and 3' slightly transmit the measuring light, so that the light emitted from the measuring light source 10 and reflected by the cornea Ef is reflected before the light splitter 1 ', the lens 2 and the light splitter 3'. The light passes through the eye observation optical path and is projected onto the area sensor 4 to form an image as shown in FIG. FIG. 2E′f is a corneal reflection image, E ′
r is a fundus reflection image. The deviation of the visual axis can be confirmed from the corneal reflection image.

Instead of using the measurement light source, for example, a light splitter 15, a lens 16, and a second light source 17 are provided on the optical axis of the anterior segment observation optical path, and the angle reflected light of the light emitted from the light source 17 during measurement is measured by the area sensor 4. It may be projected on top. In this case, for example, the light source 17 is a fixation light source, the light splitter 15 is a half mirror, and the stop 18 is a stop having a conjugate relationship with the cornea.

In the above description, the light path passing through the light splitters 1 'and 3' is used as the anterior ocular segment observation light path and the light path reflecting the light splitters 1 'and 3' is used as the measurement light path. Vessel 1 ',
The optical path that reflects 3 ′ may be the anterior ocular segment observation optical path, and the optical path that passes through the light splitters 1 ′ and 3 ′ may be the measurement optical path.

Further, the following modifications are also possible. That is, an error is displayed when the corneal reflection image position on the area sensor is out of the predetermined range during the measurement, so that the examiner can identify whether the corneal reflection image position on the area sensor is within the predetermined range. One or both of displaying the predetermined range on a monitor connected to the area sensor may be performed.

[Effects of the Invention] As described above, according to the present invention, the apparatus is simplified because the same area sensor is used to perform anterior segment observation, objective refractive power measurement, and relative displacement detection with the subject's eye. it can. Further, at this time, since the measurement light is located around the area sensor and the relative positional deviation detection light is located at the center as an arrangement on the area sensor, the formation position of the corneal reflection image is set near the center of the anterior eye part of the eye to be examined, that is, the pupil. And accurate relative position detection can be performed without being affected by iris reflection.

[Brief description of the drawings]

 1 and 2 are diagrams of an embodiment of the present invention, FIGS. 3 to 5 are diagrams of a conventional example, wherein 1 'and 3' are light splitters 1, 3 is a dichroic mirror 4 is an area sensor 10 is a measurement light source, 14 is an anterior segment illumination light source, 17 is a second light source, and 18 is an aperture.

Claims (1)

(57) [Claims] 1. An optical system for observing an anterior segment of an eye to be examined, a measuring light projecting system for projecting measuring light onto a fundus of the eye to be examined for objective refracting power, and a detection of a relative displacement from the eye to be examined. A relative position shift detection light projection system that projects relative position shift detection light onto the cornea of the subject's eye, wherein the observation light from the anterior ocular segment observation optical system, the fundus reflection light of the measurement light, and the relative position shift The same area sensor receives the corneal reflected light of the detection light and the same area sensor, and the corneal reflected light of the relative position shift detection light at the center of the area sensor and the fundus of the measurement light in the peripheral area. An eye-refractive-power measuring device, characterized in that it is configured to receive reflected light.