JPH049046B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an automatic visual field measuring device, and more particularly to an automatic visual field measuring device that increases measurement efficiency by simultaneously presenting a plurality of optotypes.

[Prior art]

Conventional automatic perimetry devices are generally configured to present one optotype sequentially in the measurement visual field, but in order to improve measurement efficiency, it is now possible to present multiple optotypes at the same time, so-called multi-point stimulation. An automatic visual field measurement device has been commercialized.

This device for simultaneously presenting a plurality of optotypes is configured to include dozens of sets of optotypes that present one optotype in each of four quadrants with the origin at the center of the visual field. In measurement using this device, any set of four optotypes is presented, and the subject answers only the number of optotypes that he or she recognizes. If this answer matches the number of presented optotypes, it is assumed that all the optotypes have been recognized, and the measurement using that set of optotypes ends, and the measurement proceeds to the next set of optotypes.

On the other hand, if the subject's answer does not match the number of visual targets presented, either ask for the position of the recognized visual target, for example, upper right, lower left, etc., or alternately light up visual targets belonging to the group one by one to recognize the target. By asking questions and finding visual targets for which there was no response, it is possible to determine whether a visual target is recognized or not.

Therefore, in the above-mentioned conventional automatic perimetry device capable of multi-point stimulation, the measurement time is shortened when all visual targets presented at the same time are recognized, but if there are visual targets that cannot be recognized, the above-mentioned problems occur. This requires a complicated procedure, which causes fatigue to the person being measured and the person being measured, and there is a risk that measurement errors may occur.

[Purpose of the invention]

The present invention was developed in view of the above-mentioned problems of conventional visual field measuring devices, and is of a type that simultaneously presents multiple visual targets, so that when there is a visual target that cannot be recognized, the subject simply recognizes the visual field. It is an object of the present invention to provide an automatic visual field measurement device that can determine whether a recognized visual target or non-recognized visual target is detected by answering only the number of visual targets created.

[Structure of the invention]

As shown in FIG. 1, the structural feature of the present invention is to store a plurality of measurement patterns formed from a plurality of optotypes at different positions, An optotype presentation means A capable of presenting a plurality of optotypes at the same time; a response means C for inputting the number of optotypes recognized by the subject; and a cognitive visual target determining means D that determines a cognitive visual target based on the number of recognized visual targets inputted by the operator. When the cognitive optotype is determined, the optotype presenting means proceeds to present the optotype of the next measurement pattern, and if the number of the presented optotypes does not match the number of recognized optotypes and the cognitive optotype determining means An automatic visual field measurement device characterized in that, when the recognition optotype cannot be determined, the optotype presenting means is configured to display the optotype by changing the combination of the optotypes that are sequentially presented until the recognition target becomes possible. It is.

Therefore, since the subject is judged whether the visual target is recognized or non-recognized by answering only the number of visual targets recognized, the burden on the measurer is light, and the automated visual field is easy to operate and has excellent measurement efficiency. A measuring device can be obtained.

The present invention also provides that the optotypes simultaneously presented by the optotype presenting means have an origin at the center of the measurement visual field.
It is configured by placing at least one in each of all, three, or two quadrants.

Next, the principle of visual field measurement using the above configuration will be explained based on FIG. 2. First, a measurement pattern in which one visual target is simultaneously presented in each of four quadrants with the center of the measurement visual field as the origin will be described. In FIG. 2, when visual indicators are presented in all four quadrants, they are represented as A, B, C, and D as shown at 100, and when visual indicators are displayed in the first and third quadrants, they are expressed as 102. They are expressed as A and C as shown in . The numbers inside circles in FIG. 2 indicate the number of visual targets that the subject could recognize. In addition, the judgment result of optotype recognition indicates the recognized optotypes as ○ and the unrecognized optotypes as ×. For example, if all the optotypes were not recognized, as shown in 104, ×× Represented as XX, the second
Visual targets B and D presented in the first and fourth quadrants are recognized, and visual targets A and D presented in the first and third quadrants are recognized.
If C is not recognized, it is expressed as ×○×○ as shown at 106.

Now, as the first step, visual target presentation A, B,
C, D100 is performed. Then, if the number of visual targets recognized by the subject is , as shown in 104, ×
It is determined that all of the visual targets A, B, C, and D are not recognized.

If the number of visual targets recognized in the first step is
will be done. Here, if the number of recognized visual targets is 1
As shown in 10, it can be determined that at least optotypes A and C were not recognized, and then the process proceeds to the fourth step, where optotype B112 is presented. Here, when the number of recognized visual targets is , the judgment result is ×××○ as shown in 114, which means that only visual target D was recognized.On the other hand, when the number of recognized visual targets is , the judgment result is As shown in 115, it is ×○××, which means that only optotype B was recognized.

On the other hand, if the number of visual targets recognized in the second step is , it can be determined that at least visual targets B and D were not recognized, as shown in 116, and then visual target A 118 is presented in the fourth step. . Here, when the number of recognized visual targets is , the determination result is XX○× as shown in 120, and only visual target C is recognized.On the other hand, when the number of recognized visual targets is , the determination result is 1
As shown in 22, it is ○×××, which means that only optotype A was recognized.

In addition, if the number of recognized visual targets is 1 in the first step, the process proceeds to the second step and visual target presentations A, C1
30 is done. Here, when the number of recognized visual targets is , a determination result of ×○×○ is obtained as shown in 106, which means that visual targets B and C are recognized.

In other cases, determinations can be made based on the same procedure as described above, so the explanation thereof will be omitted. It should be noted that when the number of recognition in the first step is , it becomes ○○○○ as shown at 140, and it is of course determined that visual targets A, B, C, and D are all recognized.

The measurement principle explained above includes a measurement pattern in which three visual targets are presented simultaneously in the first step as shown in Figure 3, and a measurement pattern in which two visual targets are presented simultaneously in the first step as shown in Figure 4. It can also be applied to measurement patterns. Figures 3 and 4 are
It is shown in the same display method as in the figure, and the determination is obtained based on the same procedure as the measurement pattern in which four visual targets are presented simultaneously, so the explanation thereof will be omitted.

〔Example〕

Embodiments of the present invention will be described below based on the drawings. The automatic perimetry device, as shown in Figure 5,
Housing 10, circular hole 12 for inserting the face of the person to be measured
a panel 14 attached to the front side of the housing 10 with It consists of a display device 22. Panel 14
A forehead rest 16 and a chin rest 1 are installed on the lower side wall near the front of the
8 is provided with a handle 24 for moving it vertically and horizontally. A hemispherical dome 23 with a large number of LEDs arranged over the entire inner surface is built into the housing 10 to present visual targets, and the eye to be measured is placed in the hemispherical dome 2.
It is configured to be located at the center of 3.

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 measured is the hemispherical dome 2.
This system monitors from the front whether the person is gazing at a fixation target placed at the center of the spherical surface of No. 3, and the anterior segment of the eye being measured is monitored through an aperture located at substantially the same position as the fixation target. to monitor.

The operating instructions for this device are as follows.

(1) Selection of measurement program. A program according to the present invention that performs visual field measurement by simultaneously presenting a plurality of optotypes, a screening program that presents optotypes one by one and measures the entire visual field in a screening manner, a meridional program that performs measurement in the radial direction, etc. One of them is selected by 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. 6. The 1/0 interface 100 receives output signals from a light pen 32 and a control switch 34 operated by the measuring person, and converts the input signals into signals that can be easily processed by the internal device. The measurement results are converted into a signal suitable for printing by the printer 32.

The CPU 102 performs main control of this device, the contents of which will be explained later as the operation of this embodiment using a flowchart. The LED matrix interface 104 is an interface for lighting the corresponding LED under predetermined conditions according to the optotype presentation conditions sequentially read out by the CPU 102, and constitutes an LED matrix with at least two transistor arrays. . Presentation condition storage means 106
stores optotype presentation conditions that determine how the LEDs of the dome 23 are lit, that is, multiple combinations of lighting brightness (intensity), position, and lighting time. The response storage means 108 stores the number of optotypes recognized by the person to be measured and the state of recognition or disapproval of the optotypes that are the measurement results, which are input by the measurer.

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.

Timing control circuit 114 is clock oscillator 1
A suitable timing signal is formed from the clock signal output from GDC 110 and CPU 102.
and output to the video memory 112.

The P/C 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 operation of this embodiment will be explained with reference to the flowchart of FIG. First, the CPU 102 selects a predetermined measurement program using the light pen 32 and starts measurement.
The program is read out from the LED matrix interface 104 and the optotype is displayed in the hemispherical dome 23 according to the presentation conditions. Visual target presentation at this stage is performed for all visual targets used in the measurement pattern of the selected program.

Subsequently, the subject informs the measurer of the number of recognized visual targets, and the measurer stores the communicated number of recognized visual targets in the response storage means 108 via the 1/0 interface 100 using the light pen 32.

The CPU 102 compares the executed optotype presentation conditions with the number of recognized optotypes and determines whether it is possible to discriminate between a recognized optotype and a non-cognitive index. If NO, proceed with the measurement step, that is, display the optotypes by changing the combination of the optotypes presented based on the above-mentioned measurement principle, and proceed to the procedure in which the subject informs the examiner of the number of optotypes recognized. This cyclic flow of progressing through the measurement steps continues until the recognition target can be determined.
On the other hand, if it is possible to determine whether the optotype is recognized or not, it is determined whether each of the optotypes is recognized or not. Changing the combination of visual targets here means
This includes cases in which one optotype is presented or a case in which one optotype to be presented is changed.

Next, determine whether all measurements have been completed,
If YES, the measurement ends; if NO,
The measurement position is changed, for example, the measurement position is moved to a more peripheral area, and the procedure proceeds to presenting all the visual targets of the measurement pattern, and measurement is performed using a new measurement pattern.

In addition, in this example, a plurality of visual targets are used.
Although the spherical viewing device using LEDs has been described, the present invention is not limited to this.
Regarding projection-type visual field measurement devices as well as visual field measurement devices with optotypes composed of light guides,
The present invention can also be applied to a plane visual field measuring device.

〔Effect of the invention〕

As explained above, the present invention is a so-called multi-point stimulation type that presents a plurality of visual targets at the same time.
If all of the presented visual targets are recognized, the visual targets are measured at once, reducing the measurement time. In addition, if some of the presented visual targets are not recognized, , the number of visual targets is gradually reduced and the subject is asked to answer only the number of visual targets that they have recognized. This allows the person being measured to know the recognized visual target and non-cognitive visual target. This has the effect of lightening the load.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the configuration of the present invention, FIGS. 2 to 4 are explanatory diagrams of the principle of visual field measurement according to the present invention, and FIG.
FIG. 6 is a perspective view of an automatic visual field measurement apparatus according to an embodiment of the present invention, FIG. 6 is a block diagram showing the configuration of the embodiment, and FIG. 7 is a flowchart showing the operation of the embodiment. 10...Housing, 22...Operation display device,
23... Hemisphere dome, 30... TV monitor, 32
...Light pen, 36...Fixation monitoring telescope, A
...Optotype presenting means, B...Presentation optotype storage means, C
...Response means, D... Cognitive visual target determination means, E...
Visual target presentation control means.

Claims (1)

[Scope of Claims] 1. An optotype that stores a plurality of measurement patterns formed from a plurality of optotypes located at different positions, and that can present a single optotype or a plurality of optotypes at the same time among the measurement patterns. a presentation means, a response means for inputting the number of visual targets recognized by the subject, and a recognized visual target from the number of visual targets presented by the visual target presentation means and the number of recognized visual targets input via the response means. and a cognitive optotype determining means for determining a recognized optotype, when the number of presented optotypes matches the number of recognized optotypes and when the cognitive optotype determining means determines a cognitive optotype, the optotype presentation means proceeds to presenting the optotypes of the next measurement pattern, and when the number of presented optotypes does not match the number of recognized optotypes and the cognitive optotype determining means cannot determine the recognized optotypes, the optotype presenting means An automatic visual field measurement device characterized in that it is configured to display visual indicators by changing the combination of visual indicators that are sequentially presented until a determination becomes possible. 2. The automatic visual field measuring device according to claim 1, wherein at least one optotype simultaneously presented by the optotype presenting means is arranged in each of four quadrants having the origin at the center of the measurement visual field. 3. The automatic display according to claim 1, wherein at least one optotype presented simultaneously by the optotype presentation means is arranged in each of three quadrants out of four quadrants having an origin at the center of the measurement visual field. Visual field measuring device. 4. The automatic display according to claim 1, wherein at least one optotype that is simultaneously presented by the optotype presentation means is placed in each of two of the four quadrants with the origin at the center of the measurement visual field. Visual field measuring device. 5. The optotype presentation means first presents all the optotypes of the measurement pattern, and when the number of presented optotypes does not match the number of recognized optotypes and the recognition optotype determination means cannot determine the recognition optotypes, 2. The automatic visual field measurement device according to claim 1, wherein the automatic visual field measuring device is configured to sequentially reduce the number of visual targets to be presented.