JPH01175829A - Ophthalmologic apparatus - Google Patents

Abstract

PURPOSE:To carry out accurate alignment quickly by providing a means for detecting predetermined information of eye to be inspected, a means for receiving light of the front portion of said eye to detect the alignment of the light with said eye and a transmitting means for transmitting the output information of said alignment detecting means to a patient. CONSTITUTION:A light flux from an infrared ray source 5 is transmitted through a liquid crystal shutter 6 and then focused on the proximity of an outlet of a nozzle 1a through a lens 7 and a dichroic mirror 8. The light flux diverges again to be reflected by the cornea of eye E to be inspected and focused on a two-dimensional position detector 11 through a concave dichroic mirror 1', transparent windows 2, 3 by lenses 9, 10. The light flux is converted to the positional signal thereof by a calculating circuit 12 to be sent to a controller 13. By comparing a position of infrared ray source 5 image reflected by the cornea in said detector 11 with a reference position is detected a positional deflection of the eye E from the optical axis in the vertical plane. On the other hand, a horizontal positional deflection is detected by selecting the light flux with the liquid crystal shutter 6.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] In the present invention, the subject himself/herself adjusts the subject's eye to the proper position of the ophthalmological equipment. The present invention relates to an ophthalmological device having a self-eye alignment device that can perform self-eye alignment.

[Prior Art] In recent years, it has been desired to popularize ophthalmological equipment that can be operated by the examiner and the examinee themselves so that both the examiner and the examinee can save labor. For example, it is desirable that intraocular pressure be measured periodically like blood pressure, and that intraocular pressure can be easily and accurately measured at home using a home-use blood pressure monitor.

By the way, when the patient himself/herself operates the ophthalmological equipment,
The subject must align their own silver precisely in place with respect to the device. This alignment consists of setting the distance between the device and the eye to be examined, that is, the working distance (WD), to a predetermined distance, and aligning the optical axis of the device and the eye axis of the eye to be examined, to within 1 mm. Requires a degree of precision.

Conventionally, as this type of positioning device, there is a contact type device in which a terminal is pressed against the cornea.

This touch-and-touch type device requires anesthesia, disinfection, etc., and cannot be said to be easy to operate by a subject. This difficulty in self-aligning the eyes is one of the reasons that prevents the spread of ophthalmological equipment that can be used at home.

In response to such a request, the present applicant filed the patent application
8533 has been proposed. Figure 84 is an example of this, and shows a non-contact tonometer. A concave mirror 1 whose focal length is the working distance of the ophthalmological device is arranged on the optical axis O1 of the device, and an opening is provided in the center of the concave mirror 1 in order to apply it to a tonometer. Nozzle la is penetrated. Then, air is blown onto the eye E located on the optical axis O1 through a nozzle 1a by an air compressor (not shown), and the cornea of the eye E is deformed in response to the pressure of the blown air. It is possible to measure intraocular pressure. At that time, apply a predetermined pressure to the eye to be examined.
In order to give the same, the eye axis of the eye E to be examined must match the axis of the nozzle 1a, and the eye E must be located at a predetermined working distance from the nozzle la. Note that since the axis of the nozzle la coincides with the optical axis o1, the alignment of the eye E to be examined can be made by aligning the eye axis and the optical axis.

By the way, for regular use with a rest of adjustment.

An object at infinity forms an image on the retina.

Therefore, when the eye E to be examined is located at the focal length f1 of the concave mirror 1, the light beam emitted from any position of the anterior segment of the eye E will be reflected as a parallel light beam by the concave mirror l, so that the examinee will be able to see his own eye. An image E' of the anterior segment of E is clearly visible in the concave mirror l. Therefore, if the working distance WD of the intraocular pressure measuring device is fl, a concave mirror l with a focal length of fl, that is, a concave mirror l with a radius of curvature rl = 2 fl, is placed on the light beam 01, and the image E' of the eye E to be examined becomes clear. By positioning the subject's eye E in a visible position, the subject's eye E can be fixed at the focal pressure glfl of the concave mirror l, that is, at the working distance fl of the device. In addition, the eye axis of the eye E to be examined is optical axis 01.
The alignment can be achieved by positioning the image E' of the anterior segment of the subject's eye E at the center of the concave mirror 1. That is, a concave mirror l having a radius of curvature twice the working distance WD of the intraocular pressure measuring device is placed on the optical axis O1.
The patient can easily position his/her own eye E to be examined so that the image E' of the anterior segment of the eye E is clearly seen in the center of this concave surface ill. It is configured so that the subject's eye E can be aligned by oneself.

[Problems to be Solved by the Invention] However, the above-mentioned conventional example has a drawback in that it is difficult to perform delicate positioning of the eye to be examined. This is because the subject performs alignment by looking at the image of his or her own pupil, that is, by focusing the image on the fundus, so the working distance may shift slightly depending on the diopter of the subject's eye, and the patient may also look at the image of the pupil. This is because the line of sight becomes unstable. Furthermore, since it is essential to recognize that the alignment is being performed in the correct direction, there is also the drawback that alignment takes time. In devices such as non-contact tonometers that require more delicate alignment, the accuracy of alignment confirmation is low with the above-mentioned conventional alignment method, and a more accurate method has been desired.

[Means for Solving the Problems] The present invention aims to provide an ophthalmological apparatus that allows a subject to perform more accurate alignment quickly, and includes an eye information detection means for detecting predetermined information about the eye to be examined. and an alignment detection means for detecting the alignment state with the eye to be examined by receiving light from the anterior segment of the eye to be examined, and a transmission means for transmitting output information of the alignment detection means to the examinee. shall be.

[Example] FIG. 1 is an example of an implementation of a non-contact tonometer according to the present invention. The concave mirror 1' is a concave dichroic mirror that reflects visible light and transmits near infrared rays, and functions similarly to the concave mirror 1 of FIG. 4, forming an image of the anterior segment of the eye to be examined on the fundus of the eye to be examined.

Behind the nozzle 1a is a compression chamber 4 sealed by a transparent window 2.3, which is connected to an airflow generator to be described later. An alignment detection system for detecting the alignment state of the eye to be examined is provided behind the compression chamber 4, and the light beam emitted from the infrared light source 5 passes through a liquid crystal shutter 6, and then passes through a lens 7, a dichroic device that transmits visible light and reflects near-infrared light. The light is focused through the mirror 8 near the exit of the nozzle la. Thereafter, the light beam diverges again, is reflected by the cornea of the eye E, passes through the concave dichroic mirror 1', the transmission window 2.3 (i.e. outside the nozzle), and is directed onto the two-dimensional position detector 11 by the lens 9.10. Focus light. The output of the two-dimensional position detector 11 is converted into a position signal of a luminous flux by the arithmetic circuit 12, and the infrared light source 5 in the two-dimensional position detector 11 has a configuration of 0 or more and is taken into the controller 13.
By comparing the position of the corneal reflection image with the reference position, a positional deviation of the eye E to be examined in a plane perpendicular to the optical axis 01 is detected. On the other hand, position detection in the optical axis and horizontal direction (that is, in the working distance direction) is performed by selecting a light beam using the liquid crystal shutter 6. That is, upon receiving an appropriate lock from the controller 13, the liquid crystal driver 14 moves the liquid crystal shutter 6 as shown in FIG.
) and (b), the two areas 6a and 6b are opened alternately. This allows the examinee's eye E if the alignment is correct.
When the optical axis direction of the LCD shutter 6 is in the correct position, the LCD shutter 6
The light beam converged on the two-dimensional position detector 11 remains stationary regardless of the drive of the two-dimensional position detector 11. When the position of the eye E in the optical axis direction shifts back and forth from the normal position and the condensing point shifts back and forth from the two-dimensional position detector 11, the light beams move in opposite directions. Therefore, if the output of the two-dimensional position detector 11 is captured in synchronization with the driving of the liquid crystal shutter 6, the desired information can be obtained. It is determined by identifying the intermediate position from the average of the output of the two-dimensional position detector 11 when the shirt shutter 6 is shown in Figure 2 (a) and the output when it is shown in Figure 2 (b), and detecting the deviation from the reference position. , and the positional deviation in the optical axis 01 direction can be found by taking the difference between the two.

As described above, the information on the position of the eye to be examined obtained by the alignment detection means is converted by the controller 13 and the LED
It is displayed on the display element 15. In this case controller 13
controls the LED display element 15, and appropriately controls the LED display element 15 based on the output of the alignment detection means. The LED display element 15 has a 5x7 dot matrix light emitting section as shown in FIG. 3(a), for example.
Arrows (b) to (e) indicating the direction of positional shift and alphabets (f) and (g) indicating front and back are displayed. This display is mapped to approximately infinity by the lens 9 via the mirrors 16 and 17, and presented to the eye E through the dichroic mirror 8, the passage window 3, and the nozzle 1a. Since this display is coaxial with the optical axis O1, it also functions as a fixation lamp for the eye to be examined.

In this device with such a configuration, the subject fixes their line of sight by fixating on the LED display element when adjusting their eye position while looking at the subject's own pupil image reflected on the concave dichroic mirror. By checking the display at the same time as the eye position is made, it is possible to understand the direction in which the eye position should be adjusted, and the limit position can be adjusted in accordance with the display. Conversely, the reflective optical system such as the above-mentioned concave dichroic mirror serves as an auxiliary means for coarse adjustment of the eye position in this device. This configuration may be unnecessary for experienced test subjects. Now, in this way, the LED
The alignment information displayed on the display element 15 is displayed on the eye E.
By observing the images, the subject can complete the alignment himself/herself.

If the controller 13 automatically operates the eye information detecting means when the output of the two-dimensional position detector 11 indicates good alignment, the eye information can be detected by the patient alone. Furthermore, by displaying the detection results of the eye information (including detection abnormalities) on the LED display element 15, the patient can display the eye to be examined multiple times as necessary without taking his/her hands off the device. Information can be detected.

Moreover, in this case, the alignment information transmission means and the eye to be examined information transmission means can be shared.

Hereinafter, the intraocular pressure measuring means will be explained as the eye information detecting means.

100 is a rotary solenoid that drives a piston 102 via a crank 101.
The air in the compressed air chamber 4 is compressed. A pressure sensor 103 is provided inside the compressed air chamber 4 to detect the internal pressure value. The compressed air passing through the nozzle 1a deforms the cornea of the subject [H]. A light source 104 for detecting when the cornea undergoes a predetermined deformation (eg, applanation). Lens 105.106,
An optical sensor 107 is also provided, and the maximum amount of light is made incident on the optical sensor 107 when the cornea undergoes the predetermined deformation. For example, considering the horizontal cornea, the light source 104 and the optical sensor 10
7 are provided at the focal positions of lenses tos and ioe, respectively.

The output signals of the pressure sensor 103 and the optical sensor 107 are sequentially input into the calculation circuit 108, and the intraocular pressure value is calculated from the output signal value of the pressure sensor 103 when the output of the optical sensor 107 reaches the maximum.

The output of the arithmetic circuit 108 can be displayed on the LED display element 15. In this case, the eye E to be examined can know the measurement result without leaving the device, and when it is determined that there is a measurement abnormality, etc., the next measurement can be continued. I can move.

In this case, it is desirable to not generate compressed air for a predetermined period of time even if the alignment is correct once the degree measurement results are obtained.

[Modified Example] In the previous embodiment, the display element was configured to simply indicate the direction of the deviation of the eye position, or even if the display element did not indicate the direction and merely displayed the absolute value of the deviation, a sufficient effect could be obtained. have In this case, the indicator may be a single LED, and control may be performed to change the blinking cycle in accordance with the absolute value of the misalignment. In this case, there is no need for the alignment detection system to detect positional deviation, and the apparatus can be simplified by replacing it with a simple light quantity detection type photodiode having a minute aperture. It goes without saying that even more effects can be obtained if the direction of the eye position shift is indicated and the display is blinked in accordance with the absolute value of the shift as shown in FIG.

In the case of the above method using a single LED as a display element, for example, if the method previously filed by the applicant (Japanese Patent Application No. 1982-1922) is used, the display element can be used regardless of the refractive error of the subject's eye. can be clearly presented, but as in the previous example, it is possible to clearly present the
When presenting the image, it is necessary to be able to adjust the presentation distance in accordance with the refractive error of the eye to be examined. The simplest method for this purpose is to make the display element 15 movable in the direction of arrow A in FIG.

Furthermore, in the previous embodiment, an alignment detection system is used in which a light beam is projected from inside the nozzle la, a corneal reflected light beam is taken out from outside the nozzle, and in addition, a two-dimensional position detector and a light beam selection means are used. The present invention is not limited by the specific configuration, and the nozzle l is used as a means of transmitting alignment information to the eye to be examined.
Although a fixation function is added by projecting a light beam from within a, the present invention is not limited to this method either. For example, as a conventional device, a system for visually observing the corneal reflection of another embodiment disclosed in an application filed by the present applicant (Japanese Unexamined Patent Publication No. 61-276533) may be used, or a system for visually observing the corneal reflection may be used. has the same effect. In addition to the intraocular pressure system, the present invention also applies to an ocular refractometer, a keratometer, an axial meter,
It can be applied to any ophthalmological device such as a fundus camera.

[Effects of the Invention] As explained above, according to the present invention, there is an effect that the alignment accuracy of ophthalmological equipment having a conventional self-eye alignment device can be improved and the alignment can be performed quickly.

Furthermore, if the alignment detection system described above is used to automatically continue measuring and photographing after alignment is completed, measurement and photographing can be completed without the subject directly operating the device during the measurement and photographing operations. Therefore, automatic measurement and photography can be performed with simpler operations, and better measurement and photography can be performed with stable alignment.

[Brief explanation of the drawing]

FIG. 1 is a diagram of a non-contact tonometer as an embodiment of the present invention;
2(a) and 2(b) are explanatory diagrams of the operation of a liquid crystal shutter, FIGS. 3(a) to 3(g) are diagrams of display examples of a display element, and FIG. 4 is a diagram of an optical system of a conventional device. In the figure, E is the eye to be examined, 1 is a concave dichroic mirror, 5
is an infrared light source, 11 is a two-dimensional position detector, 13
1 is a controller, and 15 is an LED display element.

Claims (1)

[Scope of Claims] 1. Eye information detection means for detecting predetermined information about the eye to be examined; alignment detection means for detecting the state of alignment with the eye to be examined by receiving light from the anterior segment of the eye to be examined; An ophthalmologic apparatus comprising a transmission means for transmitting output information of the alignment detection means to a subject. 2. The ophthalmologic apparatus according to claim 1, wherein the eye information detection means is operated based on the output of the alignment detection means. 3. The ophthalmologic apparatus according to claim 1 or 2, which transmits the output information of the eye information detecting means to the subject. 4. The ophthalmologic apparatus according to claim 3, wherein the output information of the eye information detecting means is transmitted to the subject by the transmitting means. 5. The alignment detecting means is an optical alignment detecting means comprising a projection optical system that projects a light beam onto the anterior segment of the subject's eye, and a light receiving means that receives the corneal reflected light of the light beam. Ophthalmological device as described. 6. The ophthalmologic apparatus according to claim 1, wherein the transmission means is a sound generation means. 7. The ophthalmologic apparatus according to claim 1, wherein the transmitting means includes a luminescent target and a projection optical system that projects the luminescent target onto the subject's eye. 8. An eye information detection means for detecting predetermined information about the eye to be examined, and an at least partially translucent device facing the eye to be examined and for reflecting light from the anterior segment of the eye to be imaged on the fundus of the eye to be examined. A concave mirror, an alignment detection means for detecting an alignment state with the eye to be examined by receiving light from the anterior segment of the eye to be examined through the concave mirror, and a transmission means for transmitting output information of the alignment detection means to the examinee. An ophthalmological device characterized by having the following. 9. The ophthalmologic apparatus according to claim 8, wherein the concave mirror reflects visible light and transmits near-infrared light. 10. The ophthalmologic apparatus according to claim 8, wherein the eye information detection means is operated based on the output of the alignment detection means. 11. The ophthalmologic apparatus according to claim 8 or 10, which transmits the output information of the eye information detecting means to the subject. 12. The ophthalmologic apparatus according to claim 11, wherein the output information of the eye information detecting means is transmitted to the subject by the transmitting means. 13. Claim 8, wherein the alignment detecting means is an optical alignment detecting means comprising a projection optical system that projects a light beam onto the anterior segment of the subject's eye, and a light receiving means that receives corneal reflected light of the light beam. Ophthalmological device as described. 14. The ophthalmologic apparatus according to claim 8, wherein the transmission means is a sound generation means. 15. The ophthalmologic apparatus according to claim 8, wherein the transmitting means includes a luminescent target and a projection optical system that projects the luminescent target onto the subject's eye.