JPH0761312B2 - Eye refractometer - Google Patents

Description

TECHNICAL FIELD The present invention relates to an eye refractometer used in, for example, an ophthalmology clinic and having a function as a lens meter.

[Prior Art] Conventionally, as an apparatus for measuring a refraction value of a lens to be inspected, there is known an automatic lens meter for measuring a refraction value by a light beam incident on a lens to be inspected to be refracted and transmitted. ing. On the other hand, as shown in, for example, Japanese Patent Laid-Open No. 63-53433, it is known that the eye refractometer originally has a function as an auto lens meter, and a model eye is placed at a position corresponding to the fundus of the eye to be examined. Then, in a state in which the lens to be inspected is placed at a position corresponding to the cornea in front of it, by applying the method of measuring the eye refraction value of the eye to be inspected, after the light flux incident on the lens to be inspected is once reflected by the model eye, The measurement is performed by entering the test lens again and refracting it.

[Problems to be Solved by the Invention] As described above, an eye refractometer for measuring the refraction value of a lens to be inspected using a model eye is known, but in the eye refractometer, the eye refractometer has the same structure as the above-mentioned auto lens meter. A lens meter having a function of performing measurement by transmitting and refracting an incident light flux has not yet been known.

An object of the present invention is to solve the above-mentioned drawbacks and provide an eye refractometer having a lens meter function with a simple structure and good operability.

[Means for Solving the Problems] In order to achieve the above-mentioned object, the eye refractometer according to the present invention includes an anterior segment observation means for an eye to be inspected, and projects a light beam for eye examination to the eye for eye refraction. In an eye refractometer having an eye refraction measuring means for performing a measurement, a projection system for projecting a measurement light beam different from the eye examination light beam on a lens to be inspected, and a photoelectric system for receiving a light beam transmitted through the lens to be inspected of the measurement light beam. Detecting means, measuring means for measuring the refraction value of the lens to be inspected based on the signal from the photoelectric detecting means, an optical path of the measurement light beam and an optical path of an eye refraction measuring means including the anterior eye part of the eye to be inspected. And an optical path branching member for sharing a part thereof.

[Function] The eye refractometer having the above-described configuration projects the measurement light beam different from the light beam for eye examination onto the lens to be inspected, and the optical path of the light beam to be measured and the optical path of the eye refraction measuring unit including the anterior segment of the eye to be inspected. And partly shared by the optical path branching member.

[Examples] The present invention will be described in detail based on the illustrated examples.

FIG. 1 is a block diagram showing an eye refraction value measuring unit facing the eye E on an optical axis 01 which substantially coincides with the visual axis of the eye E for measuring the eye refraction value of the eye E. 1 is provided. On the other hand, the measurement light source 2 for measuring the refraction value of the lens L to be inspected is arranged on the optical axis 02 which is orthogonal to the optical axis 01 between the eye E to be inspected and the eye refraction value measurement unit 1, and the measurement is performed. A lens 3, a diaphragm 4 having five apertures as shown in FIG. 2 and a contact member 5 for contacting the lens L to be tested, and a dichroic in which the reflection direction is aligned with the optical axis 01. A mirror 6, a lens 7, and an image pickup element 8 are arranged, and the output of the image pickup element 8 is connected to an image pickup means 9. The outputs of the eye refraction value measuring unit 1 and the image pickup means 9 are connected to the signal processing means 10. Further, for illumination of the eye E to be inspected, an illumination light source 11 is provided in front of the eye E to be inspected.

The contact member 5 is located at a position conjugate with the image sensor 8 on the optical axis 02.
The image sensor 8 and the lens L to be inspected are separated from S1 and are in a non-conjugated relationship. The dichroic mirror 6 transmits the infrared light flux emitted from the light source for refraction value measurement and the light source 2 for measurement (not shown) provided inside the eye refraction value measurement unit 1, and transmits the light flux emitted from the illumination light source 11. Has a light spectral characteristic of reflecting light, and the image pickup element 8 has a characteristic of sensing both visible light flux emitted from the measurement light source 2 and the illumination light source 11.

When measuring the refraction value of the eye E, first, the illumination light source 11 is turned on for alignment. The light flux from the illumination light source 11 illuminates the anterior segment of the eye E to be examined, and the reflected light flux travels on the optical axis 01 and is reflected by the dichroic mirror 6 to be reflected by the lens 7
The image is formed as an anterior ocular segment image on the image sensor 8 after passing through. This anterior segment image is converted into a video signal by the image pickup means 9 and outputted to the signal processing means 10 and outputted / displayed on a television monitor or the like not shown, and the examiner observes this and aligns the eye E to be examined. To do.

Next, when the light source for illumination 11 is turned off and a light source (not shown) in the eye refraction value measuring unit 1 is turned on, the emitted light beam is emitted from the optical axis 01.
It goes up to the eye E to be inspected, the light flux reflected by the fundus of the eye returns through the same optical path, and is received by the image pickup device or the like in the eye refraction value measuring section 1, and the light receiving position is similarly sent to the signal processing means 10 as a video signal. It is output and the eye refraction value is calculated there.

When measuring the refraction value of the lens L to be measured, the light source 2 for measurement is turned on with the lens L to be in contact with the contact member 5. The light beam from the measurement light source 2 is made into a parallel light beam by the lens 3, is incident on the lens L to be inspected, is transmitted and refracted, and then is transmitted through the dichroic mirror 6 through the diaphragm 4 and is then reflected on the image sensor 8 by the first beam. As shown in FIG. 3, five refracted light flux images M are projected. The position of this light flux image M is determined by the image pickup means 9
Is output as a video signal to the signal processing means 10. Since the relative position of these light flux images M changes depending on the refraction value of the lens L to be inspected, the refraction value of the lens L to be inspected is calculated in the signal processing means 10 from this positional relationship.

When the lens L to be inspected is eccentric from the optical axis 02, for example, as shown in FIG.
Since it moves upward, for example, the mark T is electrically generated in advance at the position of the optical axis 02 on the image pickup element 8, and the examiner observes the image pickup element 8 to form the center light flux image MO on the mark T. If they are matched, the lens L to be inspected can be easily aligned.

The refraction value is calculated if there are at least three apertures of the diaphragm 4 other than the central aperture for matching the mark T.
Instead of the diaphragm 4, a diaphragm 4'having a ring-shaped aperture as shown in FIG. 5 may be used. In this case, the light flux image M'on the image pickup element 8 is as shown in FIG. A refraction value is calculated from the shape of the ring-shaped light beam image M ', and alignment is performed so that the center of the light beam image M'is aligned with the optical axis 02.

FIG. 7 is a block diagram of an apparatus according to another embodiment, and the same reference numerals as those in the previous embodiment indicate the same members. Eye E
A dichroic mirror 6, a lens 7, a dichroic mirror 12 and an image pickup device 8 are sequentially arranged from the eye E side on the optical axis 01 where the lines of sight of the image pickup device 8 coincide with each other, and the output of the image pickup device 8 is connected to the image pickup means 9. The output of the image pickup means 9 is connected to the signal processing means 10. Further, a measurement light source 13 is provided for measuring the refraction value of the eye E to be inspected, and a lens 14, a central aperture stop 15, and a perforated mirror 16 are provided on the optical axis 03 from the measurement light source 13 to the eye E to be inspected. A mirror 17 whose reflection direction coincides with the optical axis 02, and a lens 18 is arranged on the optical axis 02. On the optical axis 04 in the reflection direction of the perforated mirror 16, a four-hole diaphragm 19 having four openings as shown in FIG. 8, a lens 20, and four wedge prisms as shown in FIG. 9 are formed. A separation prism 21 is arranged. Further, the measuring light source 2, the lens 3, the diaphragm 4, which is disposed on the optical axis 02, the lens 22, the separating prism having the same configuration as the separating prism 21 on the optical axis 02 between the contact member 5 and the dichroic mirror 6. 23 are arranged.
The dichroic mirror 6 reflects the infrared light flux from the measurement light sources 2 and 13, and transmits the visible light flux from the illumination light source 11, while the dichroic mirror 12 transmits the visible light flux from the illumination light source 11. Each has an optical spectral characteristic that reflects an infrared light flux from the measurement light source 13.

In this configuration, when measuring the refraction value of the eye E to be inspected, when the illumination light source 11 is first turned on, the light flux from the illumination light source 11 illuminates the eye E, and the light flux reflected by the anterior segment is a dichroic mirror. An image of the anterior segment is formed on the image sensor 8 after passing through the lens 6, the lens 7, and the dichroic mirror 12.

When measuring the eye refraction value, when the illumination light source 11 is turned off and the measurement light source 13 is turned on, the luminous flux from the measurement light source 13 is emitted from the optical axis 03.
Go up, lens 14, central aperture stop 15, perforated mirror 16
Then, the light is reflected by the mirror 17 and then the lens 18 and then by the dichroic mirror 6 to reach the eye E to be inspected. The light flux reflected by the fundus returns through the same optical path, is reflected by the perforated mirror 16, passes through the four-hole diaphragm 19, the lens 20, and is separated from the optical axis 04 by the separation prism 21. Further, the dichroic mirror is used.
After being reflected by 12, four light fluxes are imaged on the image sensor 8, and the light flux positions are imaged by the image pickup means 9 as in the first embodiment, and the eye refraction value is calculated in the signal processing means 10. To be done.

On the other hand, when measuring the refraction value of the lens L to be measured, the measurement light source 2
Is turned on, and the light flux passes through the lens 3 and then the lens L
After being separated from the optical axis 02 by the separation prism 23 through the diaphragm 4 and the lens 22, the light is reflected by the dichroic mirror 6 and passes through the lens 7 and the dichroic mirror 12 to form four light flux images on the image sensor 8. An image is formed, and the refraction value is calculated in the same manner from these positional relationships.

In this embodiment as well, as in the previous embodiment, the image sensor 8 for observing the anterior segment of the eye is also used to measure the refraction value of the lens L to be inspected, and the image sensor 8 and the lens L to be inspected are not conjugate. It is said that. In addition, the light flux refracted by the lens L to be inspected is used to measure the refraction value of the eye E to be inspected.
9. If the light is guided to the lens 20, the separation prism 21, the diaphragm 4, the lens 22, and the separation prism 23 are unnecessary.

[Effects of the Invention] As described above, the eye refractometer according to the present invention uses the light beam different from the light beam for the eye as the light beam for lens measurement, so that the measurement light beam is transmitted through the test lens only once. While enabling the configuration, by partially sharing the optical path of this measurement light beam and the optical path of the eye refraction measuring means including the anterior segment of the eye to be inspected, downsizing of the device in the configuration using a separate light beam, Simplification can be achieved at the same time.

[Brief description of drawings]

The drawings show an embodiment of the eye refractometer according to the present invention. FIG. 1 is a structural view, FIG. 2 and FIG. 5 are front views of a diaphragm, FIG. 3 and FIG.
6 and 6 are explanatory views of a projected light flux image on the image pickup device, FIG. 7 is a configuration diagram of another embodiment, FIG. 8 is a front view of a diaphragm, and FIG. 9 is a front view of a separation prism. Reference numeral 1 is an eye refraction value measuring unit, 2 and 13 are measurement light sources, 4 is a diaphragm, 5 is a contact member, 6 and 12 are dichroic mirrors, and 8
Is an image pickup device, 9 is an image pickup means, 10 is a signal processing means, 11 is a light source for illumination, and 21 and 23 are separation prisms.

Claims (1)

[Claims] 1. An eye refractometer including an anterior ocular segment observing means and having an eye refraction measuring means for projecting a light beam for eye examination on the eye to perform eye refraction measurement. A projection system for projecting a measurement light beam different from the above, a photoelectric detection means for receiving the transmission light flux of the measurement lens of the measurement light beam, and a refraction value of the test lens based on a signal from the photoelectric detection means. An eye refractometer, comprising: a measuring means; and an optical path branching member for partially sharing an optical path of the measurement light flux and an optical path of an eye refraction measuring means including the anterior ocular segment observation means.