JPH043212B2 - - Google Patents

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention relates to a visual field measurement method that has a plurality of optotype presentation steps, that is, automatically presents a plurality of optotypes with different sizes, brightness, and positions. The present invention relates to an automatic perimetry device, and particularly to an automatic perimetry device that can accurately measure even if object presentation is interrupted during perimetry.

[Prior art]

Generally, a perimeter meter is equipped with a screen on the inner surface of a hemisphere, and the subject's eye for visual field measurement is positioned at the center of the hemisphere, and the eyes are placed at various points on the screen while gazing at a fixation target placed at the center of the screen. This is performed by presenting optotypes of different sizes and brightness and detecting the visual field in which the eye to be examined, that is, the subject, can recognize the optotypes and the visual field in which the examinee cannot recognize the optotypes.

By the way, conventionally, data on the presentation conditions of the optotype, that is, the size, brightness, and position of the optotype, are stored in a memory circuit prior to measurement, and a predetermined program is executed according to this stored data to sequentially display the optotype. An automatic visual field measuring device has been proposed that reduces the operating burden on the examiner by presenting the visual field.

However, visual field measurement covers a wide range from the center of the visual field to the peripheral area of the subject's eye, for example, from 100 points.
It measures whether or not the examiner can recognize up to 200 measurement points, and the measurement time is usually long. Therefore, it becomes difficult for the subject's eye to gaze at the fixation target during measurement, and a situation often arises in which the measurement must be interrupted. In this case, in the conventional device described above, presentation of the optotype can be arbitrarily interrupted. However, when the visual target presentation is started again, the visual target presentation continues, and there is a problem in that the measurement result includes a measurement location in a situation where the fixation target is not gazed and becomes unreliable.

[Purpose of the invention]

The present invention was developed in view of the above-mentioned problems of conventional automatic perimetry devices when measurements are interrupted. It is an object of the present invention to provide an automatic visual field measuring device that performs visual field measurement consisting only of accurate measured values by excluding the measured values from the measured values.

[Structure of the invention]

FIG. 1 is an overall configuration diagram showing the configuration of the present invention. That is, the present invention comprises: an optotype presentation means 1 for presenting an optotype to a subject for visual field measurement; a presentation condition storage means 2 for storing optotype presentation conditions in a plurality of steps; and the presentation condition storage means 2. Based on the optotype presentation conditions stored in the optotype presentation means 1.
an optotype presentation control means 3 that sequentially supplies an optotype presentation control signal to the optotype presentation means 1, and a response means 4 for allowing the subject to respond to the optotype presented by the optotype presentation means; , a response storage means 5 that stores the response of the examinee inputted through the response means in correspondence with the visual target presentation condition being presented, and the response of the examinee stored in the response storage means. an output means 6 that outputs an optotype presentation stop signal to the optotype presentation control means 3 through an operation by the examiner, and a optotype presentation restart signal to the optotype presentation control means 3 and the response storage means 5; and a signal output means 7 for supplying an output control signal to the output means 6, and the optotype presentation control signal 3 is transmitted to the optotype presentation control signal 3 when the optotype presentation stop signal is supplied from the signal output means. The generation of the optotype presentation control signal is stopped, and then when the optotype presentation restart signal is supplied from the signal output means 7, the control steps are returned by a predetermined number of steps and executed, and the output means outputting the response of the subject corresponding to the return step after executing the control step in return instead of the response of the test subject to the optotype presented by the optotype presenting means corresponding to the step that was performed; It is configured as follows.

〔Example〕

Embodiments of the present invention will be described below based on the drawings. The automatic perimetry device, as shown in Figure 2,
A housing 10, a panel 14 provided with a circular hole 12 for receiving the subject's face and attached to the front side of the housing 10, a visual field switch 15, and a forehead rest 16 attached to the housing 10 to fix the subject's eye in a predetermined position. , a chin rest 18 , and an operation display device 22 attached to the side wall 20 of the housing 10 . The lower side wall near the entire surface of the panel 14 has a hand grip 24 for moving the forehead rest 16 and the chin rest 18 vertically and horizontally. Inside the housing 10, there are a large number of eyes on the entire inner surface for displaying optotypes.
A hemispherical dome 23 in which LEDs are arranged is built-in, and the eye to be examined is positioned at the center of the hemispherical dome 23.

The operation display device 22 includes a TV monitor 30, a light pen 32, a printer 31 located below the TV monitor 30, a control switch 34 located above the TV monitor 30, and a fixed vision monitoring telescope 36. The TV monitor 30 displays the type and distribution of the optotypes presented on the inner surface of the hemispherical dome 23, as well as a plurality of operation commands to be described later. Operate the equipment.

The printer 31 prints the measurement results. In the fixation monitoring telescope 36, the eye to be examined is the hemispherical dome 23.
This system monitors from the front whether the subject is gazing at a fixation target placed at the center of the spherical surface of the eye, and monitors the anterior segment of the eye during measurement through an aperture located at substantially the same position as the fixation target. do. The visual recognition switch 15 is operated by the subject during measurement to determine whether or not the visual target can be visually recognized.
ON: Outputs an OFF signal.

The operating instructions for this device are as follows.

(1) Selection of a measurement program, such as a screening program that measures the entire visual field in a screening manner, a meridional program that measures the radial direction, etc., and is selected using the light pen 32 before starting the measurement.

(2) Selection of the brightness (intensity) of the visual target to be presented. Selected by light pen 32.

(3) Selection of the lighting time of the visual target to be presented. light pen 32
selected by.

(4) Selection of the time interval from one presentation of the presentation target to the next presentation. light pen 3
2.

(5) Start measurement program. Although it is operated by the light pen 32, it is also operated by the control switch 34 before starting the measurement.

(6) Interruption of measurement program. Although it is also operated by the light pen 32, it is operated by the control switch 34 during measurement.

(7) Restoration of measurement program. Although it is operated by the light pen 32, it is also operated by the control switch 34 during measurement interruption.

(8) Output of measurement results from a printer, etc. It is operated by a light pen 32.

Next, the configuration of this embodiment will be explained based on FIG. 3. The 1/0 interface 100 includes output signals from a light pen 32 and a control switch 34 that are operated by the examiner, and a visual indicator that is operated by the subject to indicate whether or not the target has been visually recognized. The output signal of the switch 15 is inputted, and the input signal is converted into a signal that can be easily processed by the internal device, and the measurement result is converted into a signal suitable for being printed by the printer 32.

The CPU 102 performs main control of this device, the details of which will be explained later using a flowchart.
The LED matrix interface 104 is the CPU
This is an interface for lighting the corresponding LED under a predetermined condition according to the index display conditions sequentially read out by 102, and constitutes an LED matrix with at least two transistor arrays. The presentation condition storage means 106 is stored in the dome 23.
It stores optotype presentation conditions that determine how the LEDs are lit, ie, multiple combinations of lighting brightness (intensity), position, and lighting time. The response storage means 108 stores the response signal inputted via the visual recognition switch 15 of the subject in association with the optotype presentation condition at that time. Through this, data regarding the visibility of the subject is obtained.

A GDC (graphic display controller) 110 receives an LED array signal, a selected measurement program signal, a signal indicating the position of the lit LED, and the above response signal, and displays information on these signals on the TV monitor 30. It forms an image signal for displaying and outputs it to the video memory 112. The timing control circuit 114 forms an appropriate timing signal from the clock signal output from the clock oscillator 116, and generates a suitable timing signal from the clock signal output from the clock oscillator 116.
2 and the video memory 112.

The P/S converter 118 performs parallel-to-serial conversion on the parallel digital signal from the video memory 112 to form a video signal, and outputs the video signal to the TV monitor 30.

Next, the functions of this embodiment will be explained based on the flowchart shown in FIG. First, the subject selects a measurement program using a light pen, and then, in response to this, the CPU 102 selects a measurement program from the presentation condition storage means 1.
Read out the optotype presentation conditions from 06 and follow them.
Via the LED matrix interface 104, the LEDs of the dome 23 are turned on under predetermined conditions to display visual targets. Next, a signal indicating whether or not the subject visually recognized the presented optotype is turned on and off by turning on the visual recognition switch 15.
It is output by turning OFF and stored in the response storage means.

Subsequently, the CPU 100 determines that it is undesirable to continue the measurement because the examinee's eye is no longer gazing at the fixation target, and sends an optotype presentation stop signal using the light pen 32 or the control switch 34. It is determined whether or not an input has been made, and if there is an input, the process proceeds to the input determination of the optotype presentation stop signal, and if there is no input, the process proceeds to the determination of the end of the measurement. If it is not determined that the measurement has ended, the optotype presentation condition step is changed by one step, for example, by moving the illuminated LED to the adjacent one.
Measurements will be made such as changing to LED, and visual targets will be presented again depending on the conditions. The progress of this optotype presentation condition step depends on whether the optotype presentation stop signal is input or not.
Alternatively, the display is repeated until the display under the selected optotype presentation condition is completed.

Visual target presentation stop signal is 1/0 interface 1
00 to the CPU 102, the CPU
102 stops reading out the optotype presentation conditions, and thereby the LED matrix interface 10
4 is stopped.

After the optotype presentation is stopped, a determination is made to input a measurement stop signal indicating whether or not to stop the visual field measurement midway. Here, when a measurement stop signal is inputted by the examiner's operation, the process proceeds to a determination of input of an output command signal. If the measurement stop signal has not been input, the process advances to a determination of whether the optotype presentation restart signal is input. Here, if the optotype presentation restart signal is not input, the process goes back to the input determination of the measurement stop signal. After that, the examiner's light pen 32
Alternatively, when the optotype presentation restart signal is input to the CPU 102 via the 1/0 interface 100 by operating the control switch 34, the CPU 102
deletes, for example, the latest two steps of response signals from among the response signals stored in the response storage means 108. Further, the CPU 102 retracts the optotype presentation condition by a step corresponding to the deletion of the response signal, and then restarts the optotype presentation under the predetermined optotype presentation condition.

When a measurement stop signal is input after the measurement according to the selected measurement program is completed or the optotype presentation is stopped, the CPU 102 determines whether or not an output command signal operated by the examiner has been input, When this output command signal is input, the measurement signal is outputted by the P/S converter 30.
The measurement result is displayed by outputting it to the TV monitor 30 or printer 31. On the other hand, if the signal is not input, no output is formed and the operation ends.

In addition, in this example, a plurality of visual targets are used.
Although a spherical perimeter using an LED has been described, the present invention is not limited to this, and can be applied to a projection-type perimeter or a flat perimeter.

〔Effect of the invention〕

As explained above, when the measurement is interrupted due to the subject's eye not fixating the fixation target, etc., the present invention deletes the latest one or more measurement data before the interruption and deletes the measurement step. Since the measurement is started after returning the visual field by the amount corresponding to the value, it is possible to perform visual field measurement based only on highly reliable measurement values.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the configuration of the present invention, FIG. 2 is a perspective view of a visual field measurement device according to an embodiment of the present invention, FIG. 3 is a block diagram of the configuration of the embodiment, and FIG. 4 is an illustration of the operation of the embodiment. FIG. 1... Visual target presentation means, 2... Presentation condition storage means, 3... Visual target presentation control means, 4... Response means,
5...Response storage means, 6...Output means, 7...Signal output means, 10...Housing, 15...Visual recognition switch, 22...Operation display device, 30...TV
Monitor, 32...Light pen, 36...Telescope for fixation monitoring.

Claims (1)

[Scope of Claims] 1. An optotype presenting means for presenting an optotype to a subject for visual field measurement; a presentation condition storage means for storing optotype presentation conditions in a plurality of steps; an optotype presentation control means for sequentially supplying an optotype presentation control signal to the optotype presentation means for controlling the optotype presentation means based on the optotype presentation conditions; a response means for responding to the visual target; a response storage means for storing the response of the subject inputted through the response means in correspondence with the presented visual target presentation condition; an output means for outputting a stored response of the subject; and an output means for supplying an optotype presentation stop signal to the optotype presentation control means through an operation by the examiner, and supplying an optotype presentation restart signal to the optotype presentation control means and the optotype presentation control means. and signal output means for supplying an output control signal to the response storage means and further supplies an output control signal to the output means, wherein the optotype presentation control signal is supplied from the signal output means to the optotype presentation stop signal. and stops the formation of the optotype presentation control signal, and thereafter, when the optotype presentation restart signal is supplied from the signal output means, the control step is returned by a predetermined number of steps and executed, and the output means Outputting the response of the subject corresponding to the return step after executing the return control step instead of the response of the test subject to the optotype presented by the optotype presentation means corresponding to the returned step. An automatic visual field measurement device characterized in that it is configured to. 3. The automatic visual field measuring device according to claim 1, wherein the signal output means outputs the optotype presentation stop signal and the output control signal according to an operator's operation.