JPS6111016A - Visual sight measuring apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a visual field measurement device in which an optotype is configured by a plurality of light emitting elements, and more specifically, a visual field measuring device in which a difference in luminous efficiency of each light emitting element is stored in advance. The present invention relates to a visual field measuring device having a data-based compensation function.

[Conventional Technique 1] In order to accurately measure the visual field, it is necessary to accurately match the brightness of each presented optotype. By the way, among conventional visual field measurement devices with fixed indexes, those in which the optotypes are composed of light emitting elements (light emitting diodes, LEDs),
EDs generally have variations in luminous efficiency, and even if the same current pulse is applied, the resulting luminance will not be constant. Therefore, a visual field measuring device is provided that extracts and uses LEDs having the same luminous efficiency.

However, one perimetry device has 100 to 500 optotypes, and it is actually very difficult to extract this many LEDs with the same luminous efficiency.

In order to solve this problem, the present inventor developed a visual field measurement device that drives the LEDs with pulses based on data related to the luminous efficiency of each LED stored in advance in a memory to present an optotype with a predetermined stimulus value. was proposed in Japanese Patent Application No. 59-70641.

[Problem that the invention seeks to solve]

In a visual field measurement device that can control the luminance of the light emitting element based on data stored in advance in the memory, for example, when the light emitting element breaks down and needs to be replaced, the data is already stored in the memory. Since the light emitting element is stored, it is necessary to select and replace a light emitting element with the same luminous efficiency as the light emitting element, and it is troublesome to carry out such replacement during manufacturing and maintenance. On the other hand, it is also possible to change data related to the luminous efficiency of each light emitting element stored in memory in advance to match the luminous efficiency of the light emitting element to be exchanged, but changing this data will prevent LED failure or reduced efficiency. At times, it was a hassle to have to take the product to the manufacturing plant each time.

The present invention was made in view of the above-mentioned problems related to the conventional visual field measurement device that can control the luminance of light emitting elements, and when replacing the light emitting elements, the data regarding the luminous efficiency stored in the memory in advance is used. An object of the present invention is to provide a visual field measuring device that can cause any light emitting element to emit light with the same luminance as that before replacement without changing the light emitting element.

[Means for solving problems]

The present invention comprises a visual target made up of a plurality of light emitting elements, and displays the visual target at a predetermined stimulus value by driving the light emitting elements with pulses based on data on the luminous efficiency of each light emitting element stored in advance in a memory. A visual field measurement device configured by connecting a resistor for adjusting pulse amplitude to a required light emitting element, and adjusting a stimulation value by the required light emitting element without changing data stored in advance in the memory. I can do it.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

As shown in FIG. 1, the automatic visual field measuring device includes a housing 10, a panel 14 provided with a circular hole 12 for inserting the face of the person to be measured and attached to the front side of the housing 10, and a panel 14 that allows the person to recognize the visual target. It consists of a recognition switch 15 that is turned ON when the device is turned on, a forehead rest 16 and a chin rest 18 attached to the housing 10 to fix the limit to be measured in a predetermined position, and an operation display device 22 attached to the side wall 20 of the housing 10. .

The lower side wall near the front of the panel 14 has a handle 24 for moving the forehead rest 16 and the chin rest 18 vertically and horizontally. Inside the housing 10, a large number of light emitting elements (light emitting diodes L E D
) is built in, and the measurement target is located at the center of the hemispherical dome 23.

The operation display device 22 includes a TV monitor 30 and a light monitor 3.
2. Printer 31 placed below the TV monitor 30;
It consists of a control switch 34 and a fixation monitoring telescope 36 arranged above the TV monitor 30. The TV monitor 30 displays the type of optotype and the optotype distribution presented on the inner surface of the hemispherical dome 23, as well as a plurality of operation commands to be described later. Select an operation command using the light pen 32 and the control switch 34 to start the device. Manipulate.

The printer 31 prints the measurement results. The telescope 36 for simultaneous observation monitors from the front whether or not the object to be measured is gazing at the same target placed at the center of the spherical surface of the hemispherical dome 23, and has an aperture located at substantially the same position as the solid target. The anterior segment of the eye being measured is monitored through the -.

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 meridian direction, etc., and is selected by the light pen 32 before starting the measurement.

(2) Brightness and intensity of the presented optotype) is selected by Leigh I. Benn 32.

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

(4) Selection of the time interval from one presentation of the presentation target to the next presentation. Selected by light pen 32.

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

(6) Interruption of measurement program. It is operated by a light pen 32, but also by a control switch 34 during measurement.

(7) Restoration of measurement program. It is operated by the light pen 32, but when the measurement is interrupted, the control switch 34
It is also operated by

(8) Output of measurement results from a printer, etc. light pen 3
Operated by 2.

Next, the configuration of this embodiment will be explained based on FIG. 2.

The I10 interface 100 receives output signals from a light pen 32 and a control switch 34 operated by the measurer, and an output signal from a recognition switch 15 operated by the subject to indicate whether or not the visual target has been visually recognized. The human 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 printing by the printer 31.

The CPU 102 performs main control of the apparatus, the details of which will be explained later using a flowchart. Presentation condition storage means 1
06 is the optotype presentation condition that determines how the LED of the dome 23 is lit (i.e., the brightness and brightness of the lighting);
Store multiple combinations of position and lighting time. The response storage means 108 stores the response signal inputted via the subject's cognitive switch 15 in association with the optotype presentation condition at that time. This obtains data regarding the subject's visual field.

GDC (Graph Ink Display Controller) 11
0 is an image signal that displays the information of these signals on the V monitor 30. and store it in the video memory 11.
Output to 2.

For example, NEC (registered commercial company) μPD
7220 is available. The timing control circuit 114 forms an appropriate timing signal from the clock signal output from the clock oscillator 116, and GDC110='CPU
102 and video memory] 12.

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 it to the TV monitor 30.

The selector 120 is controlled by the output of the CPU 102 and enables either the first hash 122 or the second hash 124 to input the output to the matrix ink face 126.

The first buffer 122 is for visual target presentation, outputs the presentation condition signal from the presentation condition storage means 106 to the matrix interface 126, and outputs the presentation condition signal from the presentation condition storage means 106 to the second buffer 122.
Reference numeral 4 is for lighting at times other than presentation of the optotype, and outputs an optotype lighting signal including an efficiency correction function from a correction data storage means 128, which will be described later, to the matrix interface 126.

As shown in FIG. 3, the matrix interface 126 is used to light up the optotype presentation conditions sequentially read out by the CPU 102 and the optotypes that are not displayed, which are sequentially read out from the correction data storage means 128, in accordance with the background brightness. It is an ink face for lighting a predetermined LED 200 under a predetermined condition based on the correction data of the transistor array 202 which has floor 1 boat to number 20 boats and controls the column, and floor 21 boat to number 40 boat. and a transistor array 204 controlling the rows, forming a matrix.

200 are connected as shown in FIG.

In addition, when an LED has to be replaced due to failure or a decrease in luminous efficiency, a new LED should be replaced as shown in Figure 3.
210 and resistor 212 are connected in series.

Here the new LED 210 is the LED 200 being replaced.
A material with a luminous efficiency higher than that of is selected.

The resistance value of the resistor 212 is adjusted by adjusting the amplitude of the pulse supplied to the resistor 212 so that the brightness of the light emitting diode before and after replacement is equal.

The address signal forming means 130 forms an address signal for reading out the correction data stored in the correction data storage means 128 according to the timing signal received from the CPU 102, and sends the address signal to the correction data storage means 128.
Output to. The above address signal is the correction data storage means 1
Specify the row/column lines of table 28.

The correction data storage means 128 stores correction data for correcting differences in luminous efficiency, that is, brightness, of a large number of optotype LEDs 200 forming a matrix of columns and rows. The correction data is stored as a correction table as shown in FIG. That is, in the correction table, the line numbers of the matrix are arranged in the row direction, that is, the horizontal direction, the 1st to 20th columns are the column lines of the matrix, and the 21st to 40th columns are the row lines of the 71-socks. It is. On the other hand, the column direction, that is, the vertical direction, of the correction table represents the reading order, and 1 to 8 are the correction data in the first row of the matrix, 9 to 16, 17 to 24, . . . , 153 to 160 are the correction data of the matrix, respectively. 2nd and 3rd rows of I socks...
This is the correction data on the 20th line. This correction data storage means 128 outputs correction data in accordance with an address signal formed by an address signal forming means 130, which will be described later, and the output is performed in one line for each column. When looking at one line, it has a so-called launch function in which the previous data continues to be output as long as the output does not change when the same data is being read.

FIG. 4 shows a correction table stored in the correction data storage means 128. Assuming that the first correction data, that is, rows 1 to 8, have been read out in the correction table, during this period the boat with the transistor array 20 is Of the corresponding 21st to 40th columns, only the 21st column is all 1, and the 22nd to 40th columns are all 0, so the 21st row, that is, the port 11k121 of the transistor array 204 constituting the matrix interface 126. Only the connected LED 200 can be lit, and the L
Correction of the first row LED of the ED matrix will be performed. On the other hand, looking at the first column of the correction table, the first to fifth rows are 1 and the sixth to eighth rows are 0, so the first column and first row are controlled by the Mad Links interface 126. As shown in FIG. 5, the LED 200 lights up during the period from 1 to 5 during the successive period from 1 to 8. Looking at the second column of the correction table, the first to third rows are 1, and the seventh to eighth rows are 0, so the first row and second column controlled by the matrix interface 126 are The I, ED 200 in the column lights up for periods 1 to 6 during the period 1 to 8, so the LED 200 in the first row, second column lights up more during the period 1 to 8 than the LED in the first row, first column. 1 period) 艮< is lit, but this is the 1. period in the 1st row and 2nd column. , E, D
This is to compensate for the fact that the luminous efficiency of LFE D in the first row and second column is lower than that of LFE D. This reading continues until the last 20th row of correction data,
As will be described later, this is repeated at a frequency equal to or higher than the critical fusion frequency with visual target presentation in between. Therefore, for the person being measured, the brightness is felt to be uniform as shown in the Tarpau-Plateau law.

On the other hand, the correction data is determined according to the luminous efficiency of each light emitting element 200 so that the subject feels the same background brightness as the background illumination.

As explained above, reading the correction data of this configuration is as follows:
Overall, the LEDs are sequentially arranged from the first row of the LED matrix, that is, from the first column to the 20th column in chronological order.
200 Wr=1 data groups will be read.

In this case, a huge amount of correction data will be output from the correction data storage means 12ε at high speed, but the CPU 10
2, but not directly read by CPU 1
Since the address signal itself is formed by the address signal forming means 130 using the timing determined by 02, the CPU
No burden is placed on 102.

The background illumination device 132 illuminates the inner surface of the hemispherical dome 23 with a predetermined brightness based on the output of the 1/○ interface 100.

Next, the operation of the visual field measuring device of this embodiment will be explained with reference to FIG. When measurement starts, selector 120 changes to C.
The first buffer 122 is selected based on the output from the PUIO 2, while the indicator presentation condition signal read out by the command from the CPU 102 is input to the matrix interface 126, and the optotype is presented according to the condition.

Subsequently, the selector 12 is activated by the output from the CPU 102.
0 selects the second CPU 124 while the CPU 102
The address signal forming means 128 forms an address signal based on the output of , and outputs it to the correction data recording means 130. In response to the input of the address signal of the correction data storage means 130, the LED is turned on to the same brightness as the background illumination via the matrix interface 126.

Next, it is determined whether all the correction data in the correction data storage means 128 has been read and executed, and if No, the process proceeds to the step of forming the address signal. If it is determined that all the reading and execution of the correction data has been completed, then it is determined whether or not the measurement has been completed, and if it has not yet been completed, the step of selecting the first buffer is performed. Proceed to. This operation stops when it is determined that the measurement is complete. The above routine is designed to prevent the subject from feeling the flickering of the background illumination and to mislead the subject into thinking that the display of the optotype and the illumination of the background compensation are occurring in parallel. It is repeated at a rate corresponding to a frequency higher than the critical fusion frequency.

〔Effect of the invention〕

'The present invention comprises a visual target made up of a plurality of light emitting elements, and displays the visual target at a predetermined stimulation value by driving the light emitting elements in pulses based on data related to the luminous efficiency of each light emitting element stored in advance in a memory. In a visual field measuring device that performs This is to adjust the luminance of the target to be equal to that of the original light emitting element, and to obtain the same luminance even if the light emitting element constituting the optotype is replaced with a new light emitting element with a different luminous efficiency. It has the effect of

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a visual field measuring device according to an embodiment of the present invention, and FIG.
The figure is a block diagram of the configuration of the embodiment, Figure 3 is an explanatory diagram of a matrix of light emitting elements, Figure 4 is an explanatory diagram of correction data, and Figure 5 is an explanatory diagram of correction data.
The figure is a waveform diagram showing the lighting timing of the light emitting element based on the correction data shown in FIG. 4, and FIG. 6 is a flowchart showing the operation of the embodiment. A... Light emitting element 13... Optical target 7 display control means C... Background lighting means D... Data storage means IO... Housing I5... J Onchi switch 23... Hemispherical dome 102 ... CPU 106 ... presentation condition writing t# means 108 ... response storage means 110 ... GDC 118 ... P/S converter 112 ... video memory 122 ... first buffer 124 ...Second Hanhua 126...Matrix interface 128...
Correction data storage means 130...address signal forming means FIG. 4 FIG. 5 423456 9101N213 LED 5$J1rr LED 3?1211

Claims (1)

[Claims] A visual field measurement in which a visual target is formed by a plurality of light emitting elements, and the visual target is presented with a predetermined stimulus value by driving the light emitting elements with pulses based on data related to the luminous efficiency of each light emitting element stored in advance in a memory. A visual field measuring device, characterized in that the stimulation value is adjusted without changing the data stored in advance in the memory by adjusting the amplitude of the pulse by a resistor connected to a required light emitting element.