JPH0215441Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field The present invention provides a fixation target on the inner surface of a substantially hemispherical dome and at its pole position, and lines corresponding to latitude lines with this fixation target as the center. Pertaining to a visual field measurement device that is provided with an optotype presentation unit that sequentially presents optotypes at positions drawing concentric circles, obtains measurement data for each optotype by presenting the optotypes, and outputs the measurement data as a graph. It is.

Conventional technology Conventional perimetry devices include dynamic perimetry devices that determine the intensity of the stimulus in advance and move the stimulus position to find the boundary line between visible and invisible areas; There are two types of perimetry devices: a static perimetry device that fixes the position of the eye and measures the visual threshold at that position by varying the intensity of the stimulus. Both devices display their measurement results in an appropriate format.

FIG. 1 shows an example of measurement results obtained by a dynamic perimetry device. In FIG. 1, the symbol O indicates the center corresponding to the pole corresponding to the pole, the symbol A indicates the latitude corresponding line corresponding to the latitude, and the symbol B indicates the meridian corresponding line corresponding to the meridian. The symbol R indicates an iso-sensitivity curve obtained by connecting points with equal stimulation strength.

Incidentally, recently, the importance of glaucoma examination has been recognized, and as a method for efficiently performing glaucoma examination, it has been proposed to perform visual field measurement in the Bjerlum area. Here, the Bjelm area refers to a viewing area corresponding to an area surrounded by a line of latitude corresponding to 10 degrees and a line of latitude corresponding to 21 degrees. FIG. 2 shows measurement data in the latitudinal direction by turning on each light-emitting element on the latitudinal line in this Bjelm area, and shows the measurement results in the form of a graph. In this FIG. 2, the vertical axis shows measured values, and the horizontal axis shows longitude. Marks indicate measurement data. Longitude 0 indicates the position of the meridian that passes near the blind spot, and the measurement data is based on longitude 0.
However, the measurement data of people with normal visual field is obtained over 180 longitudes.
There is a fact that approximately symmetrical measurement values can be obtained with the degree meridian X as the line of symmetry. However, in the graph shown in FIG. 2, it is difficult to easily determine whether or not there is symmetry in the measured data with respect to the meridian X passing through 180 degrees of longitude.

Purpose of the invention The present invention was created in consideration of the above circumstances, and is intended to enable simple and easy determination of whether or not there is symmetry in the measurement data in a visual field measuring device that outputs the measurement results as a graph. An object of the present invention is to provide a visual field measuring device that provides a visual field measuring device that provides a visual field measuring device that has the following characteristics.

Structure of the device The features of this device are the measurement data obtained by presenting each visual target on one side divided into two by the horizontal meridian passing through the fixation target (meaning the meridian passing through longitude 0 and longitude 180), and The reason for this is that the graph is expressed so that each optotype on one side corresponds to the measurement data obtained by presenting each optotype on the other side, which is located at a symmetrical position with respect to the horizontal meridian, and is compared with each other. .

Embodiments Below, embodiments of the visual field measuring device according to the present invention will be described based on the drawings.

FIG. 3 shows a schematic configuration of the visual field measuring device according to the present invention, where 1 is the visual field measuring device, 2 is a housing, and the housing 2 has a dome 3 built therein. The dome 3 has a substantially hemispherical shape, and on the inner surface 4 of the dome 3, light emitting elements 5 are arranged as visual targets, and the arrangement pattern of the light emitting elements 5 will be described later. The housing 2 is provided with a panel 6 on the front thereof, and the panel 6 is formed with a face receiving hole 7 for receiving the face of the person to be measured. This face receiving hole 7 is provided with a face receiving member 8 for fixing the face, and this face receiving member 8 includes a forehead rest part 9 and a chin rest part 10.
It is composed of. The housing 2 has an operation display device 11 and handles 12 and 13 on its side.
The handle 12 has a function of driving the face support member 8 to adjust the height of the face, and the handle 13 has a function of driving the face support member 8 to adjust the horizontal position of the face. It has the function of adjusting the

The operation display device 11 has an operation screen 14, a fixation monitoring screen 15, a control switch 16, and a light pen 17. Information including a plurality of operation commands is displayed on the operation screen 14, and the control screen 14 displays information including a plurality of operation commands. An operation command can be selected using a switch 16 and a light pen 17. The fixation monitoring screen 15 displays the anterior segment of the subject's eye, allowing the measurer to monitor whether the subject is gazing at the fixation target. A printing mechanism 18 is provided at the bottom of the operation display device 11, and the measurement data is totaled and the measurement results are output as a graph.

FIG. 4 shows an arrangement pattern of light-emitting elements. Reference numeral 19 indicates a light-emitting element provided at the pole position. This light-emitting element 19 serves as a fixation target, and 20 indicates latitude 10. parallels corresponding to degrees, 2
1 indicates a latitude line corresponding to 20 degrees of latitude, and the area surrounded by the latitude lines 20 and 21 corresponds to the Bjelm area, and each light emitting element 5 corresponds to the latitude line with the light emitting element 19 at the center. Here, an LED element is used as the light emitting element 5, and 22 indicates a horizontal meridian passing through the light emitting element 19. The visual field measuring device 1 is controlled by an operation command control circuit as shown in FIG. 5, and the operational commands of this visual field measuring device are as follows.

Selection of a measurement program, for example, a screening program that measures the entire field of view in a screening manner, a meridional program that measures the meridional direction, and measures an area surrounded by 10 degree latitude and 20 degree latitude. To select the annular measurement program, etc., use the light pen 17 before starting the measurement.
selected by.

The brightness (intensity) of the presented optotype is selected using the light pen 17.

Light pen 17 is used to select the lighting time of the visual target.
It is carried out by.

The light pen 17 is used to select the lighting time interval from the lighting of one presentation target to the lighting of the other presentation target.

Starting, interrupting, and returning to the measurement program are performed by operating the light pen 17, but they can also be performed by the control switch 16.

The output of the measurement result is the light pen 17.
This is done by manipulating the .

In FIG. 5, 23 is an I/O interface, 24 is a recognition switch, and the I/O interface 23 has an output signal from the light pen 17;
The output signal of the control switch 16 and the output signal of the recognition switch 24 are input, and this I/
The O interface 23 sends and receives signals between the printer mechanism 18 and the internal device 25. The internal device 25 has a CPU 26, an LED matrix interface 27, a presentation condition storage means 28, a response storage means 29, and a GDC 30. The presentation condition storage means 28 specifies the light emitting element 5 to be turned on, It has a function of storing the combination of the brightness (intensity) when the light is turned on and the time when the light is turned on. The response storage means 29 stores the response signal input via the recognition switch 24 in association with the visual target presentation condition at that time. Thereby, data regarding the visibility of the subject can be obtained. The GDC30 functions as a graphic display controller, and sends an LED array signal, a selected program signal, a signal specifying which LED is lit,
An image signal is formed from the response signal and output to the video memory 31. For this video memory 31, for example, NEC (registered trademark) μPD7220 is used. A timing control circuit 32 forms a timing signal based on the clock signal output from the clock oscillator 33 and outputs the timing signal to the CPU 26, GDC 30, and video memory 31. The P/S converter 34 converts the parallel digital signal outputted from the video memory 31 into a video signal from parallel to serial, and displays the video signal on the TV monitor 3 having the operation screen 14.
5 and outputs it.

In order to be able to measure the Bjelm area, the CPU 26 has a built-in annular measurement program that lights up the light emitting elements 5 in the corresponding area along the latitude direction. When , for example, each light emitting element on the latitude line 21 is turned on. The respective light emitting elements that are turned on are designated by symbols A ₁ to A ₂₈ . The lighting order of each of the light emitting elements A ₁ to _{A 28} may be sequentially turned on in this code order or may be turned on randomly. If the brightness of each of the light emitting elements A ₁ to _{A 28} existing in the visual field exceeds a predetermined value, the person to be measured can perceive whether or not each light emitting element is turned on. If the brightness is below a predetermined brightness, it is impossible to recognize whether each light emitting element is turned on or not, and each light emitting element A ₁ to _{A 28}
The brightness is changed appropriately in order to obtain the brightness of the boundary that can be perceived by the person to be measured for each line of sight direction. The visibility level (threshold value) of the subject is determined as measurement data for each line of sight direction.

FIG. 6 is a graph outputting the measurement results obtained in this way. In FIG. 6, the vertical axis shows the measured value, and the horizontal axis shows the longitude. The graph shown in FIG. 6 shows each light emitting element on one side divided into two by the horizontal meridian 22 passing through the light emitting element 19 as a fixation target.
Measurement data obtained by lighting A ₂₈ to _{A 15} and each light emitting element A ₂₈ to _{A 15} on one side are horizontal meridian 2
They are displayed so that they can be compared with the measurement data obtained by lighting the light-emitting elements A ₁₃ to _{A 1} on the other side, which are located at symmetrical positions with B 1 as the boundary, and the symbol B ₁ indicates the light emission. Measurement data obtained by lighting element A ₂₈ , symbol B ₂ is measurement data obtained by lighting light emitting element A ₂₁ , symbol B ₃ is measurement data obtained by lighting light emitting element A ₁₅ . Data, code B ₄ is measurement data obtained by lighting light emitting element A ₁₄ , code B ₅
is the measurement data obtained by lighting the light emitting element _A8 ,
Symbol B ₆ indicates measurement data obtained by lighting the light emitting element A ₁ , and the light emitting element A ₂₈ and the light emitting element A ₁ , the light emitting element A ₂₁ and the light emitting element A ₈ , and the light emitting element
A ₁₅ and light emitting element A ₁₄ are located at symmetrical positions with respect to the horizontal meridian. The number of measurement data is the same as the number of light emitting elements A ₁ to _{A 28} , but in FIG. 6, for convenience of explanation, the remaining measurement data are B ₇ , B ₈ , B ₉ ,B ₁₀
Omitted except for those indicated.

According to the graph shown in Figure 6, the measured data plotted in the upper table for each longitude and the measured data plotted for each longitude in the lower table are located at symmetrical positions with the horizontal meridian as the border. Since each set of light emitting elements can be compared, it is possible to check whether there is symmetry in the pair of measurement data obtained by lighting up each set of light emitting elements located at symmetrical positions with respect to the horizontal meridian. You can clearly tell at a glance whether or not it is. In other words, the graph shown in Figure 6 corresponds to the 0° meridian and 360° meridian based on the 180° meridian, and the magnitude of the measured data is measured in the direction of moving away from each other with the horizontal meridian as the boundary. Since it is intended to be displayed, measurement data based on light-emitting elements that exist on meridians with large angles (for example, around 270°) and measurement data based on light-emitting elements that exist on meridians that have small angles (for example, around 10°) When there is a need to match and compare a pair of measurement data, it is possible to bring the pair of measurement data closer to each other and compare them. It can be clearly identified.

In the above embodiment, each of the light emitting elements A ₁ to _{A 28} on the latitude line 21 is turned on to obtain measurement data. It is also possible to output the measurement data by turning on all the light emitting elements 5 and totaling the measurement data obtained by turning on the light emitting elements 5 for each longitude in the latitude direction.

In this embodiment, a case has been described in which the present invention is applied to measurement of the Bjelm area, but the present invention is not limited to this.

Effects of the invention As explained above, the present invention provides measurement data obtained by presenting each visual target on one side divided into two with a horizontal meridian passing through the fixation target, and each visual target on the other side is divided into two by the horizontal meridian. Since the graph is displayed so that the measurement data obtained by presenting each optotype on the other side, which is located at a symmetrical position as the border, corresponds to each other and can be compared.
It is possible to clearly determine at a glance whether or not there is symmetry in a pair of measurement data obtained by lighting up each pair of light-emitting elements that are located at symmetrical positions with the horizontal meridian as a boundary. This can be expected to improve the efficiency of inspections.

[Brief explanation of drawings]

Figures 1 and 2 are explanatory diagrams of the measurement results of a conventional visual field measuring device outputted as graphs, Figure 3 is a perspective view showing the schematic configuration of the visual field measuring device according to the present invention, and Figure 4 is a diagram of the present invention. FIG. 5 is a control circuit diagram of the visual field measuring device according to the present invention; FIG. 6 is a graph showing the measurement results of the visual field measuring device according to the present invention. It is. DESCRIPTION OF SYMBOLS 1... Visual field measuring device, 3... Dome, 4... Inner surface of the dome, 5... Light emitting element, 20, 21... Latitude line, 22... Horizontal longitude line, A ₁ to A ₂₈ ... Light emitting element, B ₁ ~B ₁₀ ...Measurement data.

Claims (1)

[Claims for Utility Model Registration] A fixation target is provided on the inner surface of a substantially hemispherical dome at the pole position, and the visual targets are sequentially placed at positions that draw concentric circles corresponding to latitude lines with the fixation target as the center. A visual field measuring device is provided with an optotype presentation unit that presents the optotype, and obtains measurement data for each optotype by presenting the optotype, and outputs the measurement data as a graph. Measurement data obtained by presenting each optotype on one side divided into two by a horizontal meridian that passes through the optotype, and each optotype on one side are the same as each optotype on the other side that is located at a symmetrical position with respect to the horizontal meridian. In order to make the measured data presented correspond to each other and compare, the 0° meridian and the 360° meridian are made to correspond to each other based on the 180° meridian, and the magnitude of the measured data is A visual field measurement device characterized in that the measurement data is displayed by taking the distance.