JPH02193642A - Glance detector - Google Patents

Abstract

PURPOSE:To follow up the motion of an eye to be checked with high accuracy and to detect a glance direction at high speed by providing a photo-detection optical system to guide a light flux on a photo-electric sensor and a means to obtain the position of a nipple according to a signal from the photo-electric sensor and to detect the move of a glance. CONSTITUTION:A checker investigates the light sensitivity of a specified part in an eyeground Er by using a stimulation light source 9 for check while the picture of the eyeground is observed on a television monitor 11. In the picture of the eyeground displayed on the television monitor 11, a nipple part P is made bright by a light transmission part 7b of a shield mask 7 and a shielded part Q around the nipple part is made dark by a shield part 7a. Accordingly, when the nipple is moved with the move of the glance from an eye E to be checked by the stimulation light source 9, the bright nipple part P in the dark shielded part Q is moved to P'. The motion is caught on the television monitor 11. In order to obtain the motion of the glance, a signal from the shielded part Q is binarized based on a signal outputted from an image pickup element 5a and taken into a memory. Then, the center of gravity is computed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a line of sight detection device that can be used, for example, in a visual fixation monitoring device for a perimeter, a fundus fixation device, and various other ophthalmological devices.

[Prior Art] Conventionally, the direction of the line of sight has been detected using a method that is determined from the relative positional relationship between the corneal reflection and the crystalline lens reflection, or a method that is determined from the relative positional relationship between the corneal reflection and the pupil. However, since these methods do not directly look at the fundus of the eye, they have the disadvantage that their accuracy is not very good.

On the other hand, a method has also been proposed in which a correlation is calculated based on a specific part of a fundus image, but this method has the disadvantage that it is not necessarily easy to calculate the correlation between two-dimensional images because it takes time to calculate.

An object of the present invention is to provide a high-performance visual line detection device that can follow the movement of the subject's eye with high accuracy and detect the visual line direction at high speed.

[Means for Solving the Problems] In order to achieve the above object, the line of sight detection device according to the present invention includes: an illumination optical system that partially illuminates the nipple;
A light-receiving optical system that guides a light flux of illumination light from the illumination optical system that is diffused within the nipple onto a photoelectric sensor, and a means for determining the position of the nipple and detecting the movement of the line of sight based on the signal from the photoelectric sensor. It is characterized by:

[Operation] The line of sight detection device having the above-described configuration automatically detects the movement of the line of sight by determining the position of the nipple from the position of the light beam on the photoelectric sensor.

[Example] The present invention will be explained in detail based on illustrated embodiments.

FIG. 1 shows an example in which the present invention is applied to a fundus perimetry,
Generally, a fundus perimetry is a device that measures the visual field of an eye to be examined by fixing the line of sight, but it is necessary to detect movement of the line of sight during measurement. In FIG. 1, on the optical axis of the subject's eye E, there are an objective lens 1, a perforated mirror 2, a lens 3. light splitting member 4,
Infrared television cameras 5 are arranged. Further, a lens 6, a light-shielding mask 7, and a fundus illumination light source 8 are arranged on the incident side of the perforated mirror 2, and a moving means 10 for an examination stimulation light source 9 is provided in the incident direction of the light splitting member 4. . The fundus illumination light source 8 is for illuminating the fundus Er of the eye E to be examined, and its main wavelength distribution is infrared light. The output of the infrared television camera 5 is sent to a television monitor 11 and a signal processing control section 12.
The output of the signal processing control section 12 is connected to the moving means 10.
It is connected to the.

The light flux from the illumination light source 8 is transmitted through a light shielding mask 7, a lens 6,
The fundus Er of the eye E to be examined is illuminated through the perforated mirror 2 and the objective lens 1, and the reflected light is transmitted through the objective lens 1. Perforated mirror 2. The light passes through the lens 6 and the light splitting member 4 and enters the image sensor 5a of the infrared television camera 5 to form a fundus image on the image sensor 5a, which can be observed on the television monitor 11.

Here, the light shielding mask 7 is as shown in FIG.

It has a light shielding part 7a that shields the papilla of the subject's eye E and its surrounding area from light, and a light transmitting part 7b having a sufficiently small radius compared to the size of the papilla is provided at the center of the light shielding part 7a. The light-shielding mask 7 is configured such that the position of the light-transmitting part 7b can be adjusted according to the position of the nipple, and when a light flux is made incident on a part of the nipple from the light-transmitting part 7b, the incident light is diffused over the entire nipple. Therefore, the periphery of the nipple can be made clearer by utilizing this light diffusion effect. The test stimulation light source 9, which is installed on the fundus Er and the conjugate plane S or very close to it, is freely moved within the conjugate plane S by an appropriate moving means 10 consisting of a stay, a pin motor, etc. It is designed to give stimulation to any position. The transportation means 10 includes
Signal processing control unit 1 that has the function of presenting stimulating light and calculating the line of sight direction from the fundus image according to a program
2 outputs are connected.

The examiner can examine the light sensitivity of a specific part of the fundus Er using the test stimulation light source 9 while observing the fundus image on the television monitor II. In the fundus image displayed on the television monitor II, as shown in FIG. 1, the papilla portion P is bright due to the transparent portion 7b of the light-shielding mask 7, and the surrounding light-shielded portion Q is darkened due to the light-shielded portion 7a. There is. Therefore, when the papilla moves as the line of sight of the eye E moves due to stimulation from the stimulating light source 9, the bright papilla part P in the dark shaded part Q moves to P' as shown in FIG. , the movement can be clearly captured on the television monitor 11. To determine the movement of the line of sight, it is sufficient to determine the change in the position of the nipple portion P. Therefore, based on the signal output from the image sensor 5a, the signal from the shaded portion Q is binarized and stored in memory to calculate the center of gravity. This movement of the center of gravity often corresponds to the movement of the nipple.

FIG. 4 shows another embodiment, in which the drive section 21a,
Rotating mirrors 21 and 22 moved by mirrors 22a reflect the reflected light from the fundus Er and guide it to a photoelectric sensor 23 placed in conjugate with the fundus E. has been done.

The photoelectric sensor 23 is a so-called position detector, and includes zero-rotation mirrors 2j, 2 that output the center of gravity of the luminous flux in an analog manner.
2 are rotated in the XY force directions and moved so that the position of the nipple is always at a constant position on the photoelectric sensor 23,
The amount of movement of the line of sight can be determined from the amount of rotation.

FIG. 5 shows two -dimensional semiconductor device detectors 24a and 24b.
This is another embodiment in which the detector is used perpendicularly to the x and y directions, and the front and detector IJj detectors 24a.

It shows image A of the nipple on 24b. In this example,
The light shielding part B hangs over the edge of the nipple only in the X and Y directions. In this case, if only the light shielding part B is extracted using the signals from the optical position detectors 24a and 24b, the coordinates of the edge in the X direction and the Y direction can be determined, so that the position of the nipple can be determined.

[Effects of the Invention] As explained above, the line of sight detection device according to the present invention can determine the movement of the line of sight based on the position of the papilla while observing the fundus image, and therefore can improve the accuracy of line of sight detection. It also has the advantage of being able to detect eye movement at high speed because signal processing is relatively simple.

[Brief explanation of the drawing]

The drawings show an embodiment of the line of sight detection device according to the present invention.
The figure is a configuration diagram when the present invention is applied to a fundus perimetry;
The figure is a front view of the light-shielding mask, Figure 3 is an explanatory diagram of the movement of the nipple, Figure 4 is a perspective view of the main part of another embodiment, and Figure 5 is a diagram showing the position of the nipple when using an image sensor. It is an explanatory diagram. 1 is an objective lens, 2 is a perforated mirror, 4 is a light splitting member, 5 is an infrared television camera, 5a is an image sensor, 7 is a light shielding mask, 8 is a light source for fundus illumination, 9 is a stimulation light source for examination, 1
0 is a moving means, 11 is a television monitor, 12 is a signal processing control unit, 21.22 is a rotating mirror, 23 is a photoelectric sensor, 2
4a and 24b are one-dimensional optical position detectors. Patent applicant Canon Co., Ltd.

Claims (1)

[Claims] 1. An illumination optical system that partially illuminates the nipple; a light receiving optical system that guides the light flux of illumination light from the illumination optical system that is diffused within the nipple onto a photoelectric sensor; A line-of-sight detection device comprising means for detecting movement of the line-of-sight in order to determine a position.