JPH11309116A - Optometry device - Google Patents

Abstract

(57) [Problem] To improve operability of measurement by using a low-cost and small-sized display member. When an examinee puts a forehead on a forehead rest and looks at a target through a window, an imaging part captures an image of an anterior eye of an eye to be inspected, which is illuminated by an infrared light source. The signal is taken into the arithmetic means and analyzed, and an eye graphic G representing the eye E to be inspected by computer graphics is displayed on the display means 2 based on the result. Using this eye figure G, the degree of pupil blur is recognized, the pupil position is accurately calculated when the subject is in focus, and the state of the eyelids and blinking are detected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optometry apparatus such as an auto-refractometer and a fundus camera.

[0002]

2. Description of the Related Art In a conventional optometry apparatus, a video signal from an imaging means for imaging an eye to be inspected with infrared light is displayed on an image display means in an eye observation optical system, and an examiner views the image. The position of the eye to be examined is determined, and the state of the eye is observed. In addition, there is also known an apparatus which temporarily captures a video signal from an imaging unit into a memory and displays the video signal on the video display unit intermittently again.

[0003]

However, in the above-mentioned conventional example, the image display means capable of displaying halftones is expensive, which hinders the cost reduction of the apparatus. When displayed on a screen, it is difficult to see, and there is a problem that the device cannot be miniaturized. In addition, an intermittent display device has a problem in that it takes a long time to display, which is not preferable for positioning a fast-moving eye.

An object of the present invention is to solve the above-mentioned problems,
It is an object of the present invention to provide an optometry apparatus in which measurement operability is improved by using a low-cost and small display means.

[0005]

According to the present invention, there is provided an optometry apparatus for projecting a light beam onto an eye to be inspected to perform an optometry, and irradiating the eye with an infrared ray to irradiate the eye. It is characterized by comprising detecting means for detecting an optometry, and display means for displaying a graphic representing the eye to be inspected based on the detection by the detecting means.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the illustrated embodiment. FIG. 1 shows a configuration diagram of an auto-refractometer according to an embodiment, in which a display means 2 such as a liquid crystal plate is disposed on the upper surface of a housing 1, and a forehead rest 3 and an eye E to be examined are provided on the subject side. A viewing window 4 is provided. Further, inside the housing 1, a measuring optical system 5 and a driving means 6 for driving the measuring optical system 5 three-dimensionally for alignment are accommodated.
In the measurement optical system 5, an objective lens 7, light splitting members 8 and 9, a perforated mirror 10, an aperture 11, a lens 12, and a measurement light source 13 are sequentially arranged on an optical path substantially at the center of the window 4. An infrared light source 14 and a lens 15 are arranged near the objective lens 7. A lens 16, an aperture 17, and an imaging unit 18 are arranged on an optical path in the reflection direction of the light splitting member 8.
In the reflection direction of the perforated mirror 10, a six-aperture stop 21, a separation prism 22, a lens 23, and an imaging unit 24 are sequentially arranged.

[0007] With such a configuration, the subject can use the forehead 3
And the target 20 is viewed from the window 4. The imaging unit 18 images the anterior segment of the eye E illuminated by the infrared light source 14,
The signal is sequentially taken in by an arithmetic unit (not shown) and analyzed. Based on the analysis, an eye graphic G representing the eye E to be inspected by computer graphics is displayed on the display unit 2. Further, the position and the focus state of the eye E are recognized, and the driving unit 6 is driven based on the recognized position to perform the alignment. A light beam from the measurement light source 13 is projected onto the eye E, and the fundus reflected light returns along the same optical path and is received by the imaging means 24, analyzed by arithmetic means (not shown) to calculate a refraction value, and based on the calculated refractive index, The diopter is adjusted and a refractive power measurement is performed.

FIG. 2 shows an image of the eye to be examined picked up by the image pickup means 18. The video signal is captured by the arithmetic means at 15 to 30 Hz, and the position of the eye E, the position in the optical axis direction due to the degree of blur, the pupil diameter, the degree of eyelid drop, blinking, and the like are analyzed. The pupil can be recognized as having a very low signal level and an area. The position of the eye E on the screen is determined by recognizing the pupil. In the blurred image, the position of the eye figure G to be displayed on the display surface of the display means 2 is determined with the center of the pupil as the center of the pupil. The degree of pupil blur is recognized from the rising edge signal of the lower half edge of the identified pupil, and the eye figure G is shifted and displayed as a double image as shown in FIG. Expressed in quantity.

When a certain degree of focus is achieved, the pupil position is accurately calculated. The dark part of the image obtained earlier is not used because the upper eyelid has an eyelid, and the center is calculated using the lower edge assuming that the pupil is a circle, and the pupil diameter is calculated at the same time. The size of the pupil is displayed as shown in FIG. When the pupil diameter is insufficient for the measurement, the display of the pupil part is blinked, and a warning character is displayed at the same time. As described above, by integrally displaying the eye graphic G and the warning display,
The operability is improved and the measurement can be performed efficiently.

Incidentally, the position and blur of the eye E to be examined are determined by the infrared light source 1.
Alternatively, the calculation may be performed using the corneal reflection image 14 'of FIG. When the eye E is looking in the optical axis direction, the corneal reflection image 14 'of the infrared light source 14 arranged symmetrically with respect to the optical axis is formed substantially symmetrically with respect to the center of the pupil a. Recognize with high signal.

Further, the eyelid can be recognized from the position and the focus of the upper edge of the dark part recognized as the pupil. Since the eyelid is located 5 to 8 mm ahead of the pupil, when the focus is adjusted to the pupil, the eyelid portion is blurred. Therefore, if the lower edge is focused and the upper edge is blurred, it is recognized that the eyelid is hung on the pupil, and the degree of lowering of the eyelid is recognized from the position of the blurred edge with respect to the center of the pupil, The state in which the eyelids hang on the pupil is displayed by an eye figure G with the eyelids lowered as shown in FIG.
When the eyelid is lowered enough to interfere with the measurement, a warning is issued by blinking the eyelid portion. In the case of a blink, the eye position cannot be calculated because the pupil is hidden, but the blink is about 0.1 second. If the eye cannot be recognized within this time, it is recognized as a blink and the eye figure G Blink display with all eyelids lowered.

Note that the distance of the eye E in the optical axis direction can be detected by using another photoelectric detection system instead of detecting the focus of the pupil image. The detection may be performed based on whether or not the corneal reflection image 14 'is displayed.

In the above-described embodiment, the positioning drive is performed automatically, and the display is used merely for confirmation. However, it is possible to perform the positioning manually while watching the display. Since the size of the display member can be reduced, the weight can be reduced and the operability is improved.

Although the above description has been made with respect to the auto-refractometer, also in the case of the fundus camera, the signal of the anterior ocular segment imaging means is analyzed to display the ocular figure G, and the position and state of the eye E to be examined are determined and photographed. can do. In addition, since the state of the subject's eye E required for optometry is limited to three-dimensional positions, movements, pupils, eyelids, blinks, and the like, it is possible to use a simple eye figure G that does not take much time to display, The position state of the fast-moving eye E can be reliably displayed.

[0015]

As described above, the optometry apparatus according to the present invention irradiates infrared light to detect an eye to be examined, and displays the state of the eye to be examined in a simple figure based on the detection result. Since it is possible to use a small and inexpensive display member that does not require halftone display, it is possible to reduce the weight and size, and since the display does not take much time, it is necessary to sequentially show changes in the state of the eye to be examined. And operability is improved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment.

FIG. 2 is an explanatory diagram of an image of an imaging unit.

FIG. 3 is an explanatory diagram of a double-displayed eye figure.

FIG. 4 is an explanatory diagram of an eye figure showing a size of a pupil part.

FIG. 5 is an explanatory diagram of an eye figure when an eyelid is applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Housing 2 Display means 5 Measurement optical system 6 Driving means 13 Measurement light source 14 Infrared light source 18, 24 Imaging means 20 Optotype

Claims (3)

[Claims] 1. An eye examination means for projecting a light beam to an eye to be examined to perform an eye examination, a detection means for irradiating an eye to be examined with infrared light to detect the eye to be examined, and an eye to be examined based on the detection by the detection means. An optometry apparatus comprising: display means for displaying a figure to be represented. 2. The optometry apparatus according to claim 1, wherein the detection unit includes an imaging unit configured to image the anterior segment of the eye to be inspected. 3. The optometry apparatus according to claim 2, wherein a graphic representing a position or a state of the eye to be inspected is displayed based on a signal from the imaging unit.