JPH02224636A - Retina potentiometer - Google Patents

Abstract

PURPOSE:To selectively obtain a flash ERG and a flicker ERG with one device by operatingly controlling a flash light stimulating means and a flicker light stimulating means, and on the other hand, arranging the flicker light stimulating means to a contact lens type electrode holding body. CONSTITUTION:When a start button 10 is pushed, a light stimulation automatic starting mechanism is operated, in waiting for a noise level to be stabilized in a retina potential to be gathered based on inputs from an electrode holding body 6, an irrelative electrode 7 and an ear electrode 8, a xenon lamp 3 or a light-emitting body in a contact lens type electrode holding body 6 is automatically operated, a light emission is executed, and an aimed ERG waveform is obtained. For the contact lens type electrode holding body 6 attached to an eye ball, a main body part 17 is connected to the back part of a detecting part 16, and a convex lens 18 is provided. The potential of a cornea surface is detected by a relative electrode E, and the detected potential is conducted to a prescribed terminal.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to an M4 membrane electrometer, and more particularly to a retinal potential measuring device that can easily measure retinal potentials in response to two different types of optical stimuli.

(Background Art) Human or animal eyes usually have (+) on the corneal side,
There is a resting potential indicating a (-) potential on the posterior pole side, and it is known that the resting potential changes at the moment when light hits the retina and the moment when the light disappears.

This phenomenon is widely used in inspections, research, etc., and for example, the so-called ERG (Electr) is a record of such potential fluctuations with time as the horizontal axis.

retinogravs: 1iI membrane potential,
This captures action potentials in the retina. For this reason, such ERG is the most widely used electrophysiological test of the retina or vision, and the electric potential fluctuation of the eyeball has the characteristic that it is an objective response, for example, It is widely used as an effective testing method for retinal function tests when the fundus cannot be seen through due to opacity of the transparent body, and for diagnosing retinochoroidal diseases.

By the way, flash ERG, which captures changes in retinal potential in response to a single light irradiation (flash light), has been widely used as ERG, and has become one of the important testing methods for retinal examination. However, such flash ERG only tests the overall function of the retina, and some diseases have been recognized in which the retina passes the entire retinal test but fails the local test. For example, the flicker ERG obtained in response to irradiation with repetitive stimulation light (flicker light) at a high frequency of about 30 Hz is
Today, in addition to the flash ERG mentioned above, it is possible to selectively examine vertebral body function within the retina.
Alternatively, it is desired to obtain flicker ERG instead.

This is because cones are particularly concentrated and distributed in the center of the retina, function in bright light, distinguish colors, and are an important part that can also affect visual acuity.

Therefore, as a flicker stimulus to obtain such flicker ERG, square wave light stimulation is in principle used, but when xenon discharge light stimulation is adopted for this purpose, a high repetition stimulation frequency is required. The problem was that it was difficult to obtain a specified amount of light repeatedly. That is, the problem is that repeated charging cannot keep up with repeated discharging, and the amount of light decreases. Furthermore, the method of obtaining flicker light by intermittent light from a light source that emits light continuously using a shutter has an inherent problem in that it is difficult to cause the shutter to follow the flicker at a high frequency. That is, the shutter starts to close before it is fully opened, and the specified stimulation intensity may not be obtained.

For this reason, a conventional electroretinometer for obtaining flash ERG cannot be used as is to obtain flicker ERG, and a special device must be separately installed for flicker ERG. It was necessary to measure it separately.

In addition, uniform illumination of the entire retinal area is generally an important requirement for electroretinography measurements, whether it is a flash stimulus or a flicker stimulus. A method has been studied in which a flash discharge tube is attached, the flash light from the discharge tube is irradiated onto the inner surface of the dome through a diffuser, and the subject's eye is directed toward the inner surface of the dome, thereby irradiating a fairly uniform stimulus light over a wide area of II. However, installation of such a hemispherical dome for irradiating the entire retina requires a very large space, which has the inherent problem of increasing the size of the device itself.

On the other hand, in response to light stimulation such as the aforementioned flash light or flicker light, an effective method for deriving action potentials that are generated widely in the retina is usually to directly or indirectly direct or indirectly generate action potentials on the corneal surface of the eyeball. A method is adopted in which the potential difference is detected and measured as a potential difference between an electrode that is brought into contact (in other words, a related electrode) and an electrode that is brought into contact with the forehead or the like and whose potential is set to 0 (an indifferent electrode).

In such a retinal potential measurement, with the subject wearing a predetermined electrode, the examiner, for example, while observing the monitor, confirms that the noise level has stabilized, and at that point, By applying flash (light) stimulation or flicker (light) stimulation to the subject's eyes, each E
An RG waveform is obtained. In order to confirm the noise level at this time, a method is generally adopted in which the examiner is informed of the noise information by the amplitude of a bright spot on the monitor screen.

In addition to the so-called external noise that exists inside the measuring device itself or that originates from sources other than the device, such noise may also be generated from the subject's eye movements or improper attachment of contact lens electrodes. There is noise, but
In order to obtain a good ERG waveform, it is important to perform measurements with as little noise as possible.

In addition, as another method of noise monitoring, a noise observation method using a level meter incorporating a large number of light emitting diodes has been proposed, but in the same way as above, after the examiner judges the noise information using the level meter, In order to apply a predetermined optical stimulus, a start button was pressed, and whether or not the noise level had stabilized had to be determined by the examiner.

(Problems) However, with the optical stimulation mechanism of the conventional electroretinometer as described above, since the operation is based on the subjective judgment of the examiner, there are many inherent problems that cannot be avoided. Met. In other words, during the operation for applying such optical stimulation, the examiner must continue to monitor the monitor, and therefore, the examiner must keep an eye on the subject's fixation state, contact lens electrode attachment state, etc. immediately before the test. This makes it difficult to monitor or observe the condition of the examiner. As mentioned above, in order to obtain an effective ERG waveform, this is done in order to have the examinee fixate on the fixation lamp installed in the strobe, so that the examinee suppresses eye movements as much as possible. This is because people always need to be careful.

Of course, if the contact lens is removed or floating off the cornea, the test will fail. As described above, conventional retinal potential measurement has always had the problem that it is difficult for the examiner to observe the subject.

Furthermore, the task of having the examiner judge noise information from the monitor and quickly press the start button (optical stimulation) requires skill on the part of the examiner, and may sometimes lead to measurement failure. This is said to be mainly caused by noise caused by human eye movements, but since eye movements are unstable and irregular, the noise information on the monitor is also extremely irregular. This is because, especially when performing binocular measurements, it is extremely difficult to press a button or the like at the moment when the noise in both eyes enters the stable range at the same time.

(Solution Means) Here, the present invention has been made against the background of the above circumstances, and an object to be solved is to selectively and easily combine fludge, ERG, and flicker ERG into one device. Therefore, it is an object of the present invention to provide an electroretinometer that can measure flicker ERG continuously with flash ERG, which has been widely used up until now.

Furthermore, the present invention eliminates noise contamination, eliminates the examiner's subjective judgment regarding noise information, and provides highly reliable ER.
Another objective is to obtain an electroretinometer that can easily obtain G waveforms.

(Solution Means) In order to solve such problems, the present invention is directed to '414
In an electroretinometer for determining membrane potential, (a) a predetermined electrode is placed on the inner concave surface of a bowl-shaped detection part that is attached to the eyeball and in contact with the corneal surface, while a predetermined electrode is placed on the back of the bowl-shaped detection part. A hemispherical convex lens protruding toward the bowl-shaped detection section that can transmit light incident from the back surface is provided on the continuous main body section, and the light passes through the convex lens and reaches the bowl-shaped detection section. (b) a contact lens-type electrode holder that is guided to the corneal surface in contact with the cornea; (C) a semiconductor device disposed near the focal point of the convex lens of the electrode holder to generate flicker light and irradiate it to the bowl-shaped detection unit side through the convex lens; (d) a control device that selectively controls the operation of the flash light stimulation means and the flicker light stimulation means and causes each of the light stimulation means to generate a predetermined light stimulation; The gist thereof is an electroretinometer characterized by having the following.

Further, in the present invention, the retinometer having the above configuration further includes an amplifying means for amplifying the retinal potential obtained based on the signal taken out by the electrode of the contact lens type electrode holder; noise detecting means for detecting noise from the amplified retinal potential; first determining means for determining whether the amount of noise detected by the noise detecting means is below a predetermined setting value; and the amount of noise. and a second determining means for determining whether the amount of noise is maintained at a predetermined set value or less for a predetermined time or longer, Another feature of the present invention is that in such a case, the control device automatically generates a predetermined optical stimulus.

(Operation/Effect) As described above, the present invention provides a predetermined flash light stimulation means and flicker light stimulation means, and controls their operation by a control device, while providing an electrode for extracting the potential of the corneal surface. The flicker light stimulation means is disposed on a contact lens type electrode holder provided with a contact lens type electrode, so that flicker ERG can be measured. The flicker ERG is guided from the back side to the front side through the transparent part provided on the holder and irradiated onto the subject's eye, and the flash stimulus is applied through the contact lens type electrode holder. At the same time, it has become possible to easily measure flash ERG.

In particular, a flicker light stimulation means made of a semiconductor light emitting element that provides flicker stimulation is provided near the focal point of the convex lens,
A contact lens type electrode holder is used, which is configured to diffuse the light and irradiate the eye to be examined, and is provided with a light-transmitting part that transmits light irradiated from behind to the front. As a result, it has become possible to stably obtain square wave light as a flicker stimulus, and it has also become possible to extract the potential appearing on the corneal surface to the outside using the same electrode holder for flash stimulation.
Flash ERG and Flicker E can be performed using the same device.
This made it possible to measure RG.

In addition, the contact lens type electrode holder itself used in the present invention has the effect of diffusing light, which greatly expands the range of light stimulation that is irradiated from the pupil to the retina. In some cases, it is easy to fix the distance of the cornea from the light source to a substantially constant value, and the measurement conditions can be easily made constant. This made it possible to enjoy the same effect as when using a conventional hemispherical dome.

Furthermore, according to another aspect of the present invention, the determination of noise information before retinal potential measurement is not performed based on the subjective judgment of the examiner, but a predetermined amount of noise (noise level) is set within the ERG measuring device. The system is designed to automatically apply a predetermined flash light stimulus or flicker light stimulus after maintaining the permissible range within a certain period of time. After completing the necessary preparations for the test, such as attaching the electrodes, all you need to do is press the start button, and the automatic optical stimulation mechanism described above will function to generate a valid ERG waveform.
It can be provided more easily than before.

That is, according to the noise information processing-automatic optical stimulation start mechanism according to the present invention, the measurement of retinal potential itself becomes extremely simple, and the examiner can always observe the condition of the subject, which improves measurement accuracy. As a result, measurement failures due to improper attachment of electrodes can now be prevented.
Furthermore, since the noise level can be set, it is easier to obtain a good ERG waveform with less noise, and furthermore, it is possible to improve the reproducibility of the ERG waveform because the examiner's subjective judgment regarding noise information can be eliminated. .

(Example) Hereinafter, in order to clarify the present invention more specifically, examples according to the present invention will be described in detail based on the drawings.

First, FIG. 1 shows an example of an electroretinometer according to the present invention, in which 1 is a main body of the device, and a flash box 2 is provided on the side of the main body 1. Inside the flash box 2, a U-shaped xenon lamp 3 (xenon flash discharge tube) is provided for providing flash (light) stimulation, and furthermore,
A fixation lamp 4 is provided in the center of the xenon lamp 3 for the subject to fixate upon during measurement.

This fixation lamp 4 has the purpose of stopping the movement of the subject's eyes by gazing at it and preventing the generation of noise. In order to facilitate the attachment of electrodes, etc. to the subject, high-intensity LE with variable brightness is used so that it can also be used for illumination.
D is used.

In addition, the subject was given flash ERG and flicker ER.
A contact lens type electrode holder 6 used in the present invention, which can be used commonly for measuring G, is attached to the left and right eyes, an indifferent electrode 7 is placed on the forehead, etc., and an ear electrode 8 is used for grounding.
is attached, and the target retinal potential can be measured, for example, in a supine position as shown in the figure.

In addition, the contact lens type electrode holder 6 and the indifferent electrode 7,
The ear electrodes 8 are each connected to a predetermined terminal of the device main body 1.

Furthermore, the operation unit 5 provided on the side of the main body 1 of the electroretinometer displays the fixation state (including noise) of the subject, as shown in an enlarged view in FIG. 2, for example. Fixation monitor 9, start button 10 that applies optical stimulation when switching to manual operation and activates the optical stimulation start mechanism when switching to automatic operation, switching button 11 that switches between automatic operation and manual operation, flash ERG and flicker ERG selected. Button 12, paper feed to feed the printer that records each ERG (electroretinogram)! 114 and a lighting button 13 for illumination by changing the brightness of the fixation lamp 4.

When automatic operation is selected by pressing the automatic/manual switching button 11 of the operating section 5, the start 1
If you press 010, the optical stimulation automatic start mechanism will operate, and the noise level will stabilize in the retinal potential collected based on the input (No. 13) from the electrode holder 6, indifferent electrode 7, and ear electrode 8. Wait, the light emitting body (LED) inside the xenon lamp 3 or contact lens type electrode holder 6 will automatically
) to emit light and obtain the desired ERG waveform.

Furthermore, as shown in FIG. 3, the contact lens type electrode holder 6, which is attached to the left and right eyeballs of the subject, has a cylindrical body part 17 on the back of the bowl-shaped detection part 16. It has an integrally connected structure, and a convex lens 18 is fitted into the main body part 17 so as to protrude toward the detection part 16, and furthermore, this convex lens 1
A semiconductor light emitting element, such as a light emitting diode (LED) 19, is provided at the focal point 8 as a flicker light stimulation means. Further, the convex lens 18 is made translucent so that light can enter from the back surface thereof, and furthermore, a bowl-shaped detection section 16 facing the convex lens 18 is provided.
The curved portion 16a is also a transparent portion. Furthermore,
On the inside of the bowl-shaped detection section 16, a concave surface in contact with the corneal surface is provided with a related-art electrode E, so that the potential of the corneal surface is detected by the electrode width. This detected potential is then guided to a predetermined terminal of the device main body 1, as described above.

Therefore, in the contact lens type electrode holder 6 having such a structure, flicker light with a high repetition stimulation frequency emitted from the LED 19 and flash light from the xenon lamp 3 incident from the back surface of the convex lens 18 are The light is diffused by the convex lens and spreads over the subject's entire visual field, making it possible to apply uniform light stimulation to substantially the entire retinal visual field.

In addition, in this device, the xenon lamp 3 and the contact lens type electrode holder 6 in the flash box 2 are arranged so as to be located substantially on a vertical line including the fixation lamp 4. This makes it possible to keep the distance between the optical stimulus part and the cornea approximately constant, making it extremely effective in measuring retinal potential. That is, the center LED of the contact lens type electrode holder 6
When the examiner confirms that the fixation lamp 4 is irradiating the area around 9, it becomes possible to apply optical stimulation approximately vertically and at a substantially constant distance between the optical stimulation part and the cornea. This means that when a subject is given stimulation using a conventional hemispherical dome, it is possible with this device to do exactly the same thing as having the subject fixate on the beam center. Therefore, in measuring the retinal potential, it is possible to apply a stimulus close to the ideal irradiation of the entire retina.

In addition, in the electroretinometer of this embodiment, it is also possible to perform measurement based on noise information judgment by the examiner as in the past, and in that case, manual operation can be performed using the automatic/manual switching button 11. Select the side and while looking at the same vision monitor 9,
It is possible to operate the start button 10 according to the examiner's subjective judgment and to apply optical stimulation to the examinee. In addition, this fixation monitor 9 does not use a cathode ray tube like the conventional ones, but uses a lamp display to blink in response to a predetermined amount of noise, making it simpler, cheaper, and lighter than conventional ones. . In some cases, there may be times when it is desired to continuously extract flash ERG and flicker ER (1) as data, and a continuous measurement button 15 is provided for that purpose. Operation of this continuous measurement button 15 Specifically, by pressing the button 15 and then pressing the start button 10, two types of ERG will be continuously and automatically measured.

By the way, inside the device main body 1 of such a retinometer,
A mechanism for implementing a block diagram of an electroretinometer as shown in FIG. 4 incorporating a light stimulation automatic start mechanism is built-in. Here, the electrode connection terminal 20 is connected to the related electrode E, the indifferent electrode 7, and the ear electrode 8 of the contact lens type electrode holder 6 worn on the subject as shown in FIG. , and the retinal potential picked up by the electrodes E and 7.8 is transmitted to the left and right isolation amplifiers 22a, in the case of binocular measurement.
22b to respective amplifiers 24a.

24b, or in the case of monocular measurement, from either isolation amplifier 22a or 22b to the corresponding amplifier 24a or 24b to the left and right channel (left and right eye) changeover switch 26, AD converter 28. , flash ERG and flicker E
After the waveform is processed by a microcomputer 30 which also functions as a control device for switching between RGs, a selected desired ERG waveform is automatically recorded by a printer 32 such as a thermal dot printer. .

In addition, the isolation amplifiers 22a and 22b of each channel (hibernation) leave the necessary waveform parts (
The amplifier 24 amplifies the noise by limiting the frequency range) and amplifying the noise to a certain extent.
Together with a and 24b, it constitutes an amplification means for amplifying the retrieved retinal potential, and the amplifier 24 of each channel
The outputs from a and 24b are input to the input monitors 34a and 34b of the corresponding channels, respectively, and are also input to the left and right channel changeover switch 26, where they are input to the left and right channel changeover switches 26 and 24b, respectively. It is possible to selectively switch among the three types of retinal potential measurements.

The optical stimulation automatic start circuit includes left and right noise detection circuits 36a and 36b, a time setting circuit 38, and an optical stimulation signal trigger output section 40. There, the outputs from the amplifiers 24a and 24b of each channel are transmitted to left and right noise detection circuits 36a and 36b, respectively.
There, noise is detected from the retinal potentials of the left and right eyes, and it is determined whether the amount of detected noise is less than a predetermined set value. Next, the signals output from the detection circuits 36a and 36b are guided to a time setting circuit 38, where the signals are set in advance.
Based on the predetermined time during which the noise it (noise level) is below the predetermined set value, it is determined whether or not it has been maintained for more than the predetermined time, and whether the noise amount is below the predetermined set value and When the time is maintained for a predetermined time or more, a predetermined signal is output from the time setting circuit 38, and based on the signal, a light stimulation signal is output from the light stimulation signal trigger output section 40 to the microcomputer 30, As a result, the light emitting section (the xenon lamp 3 or the LED 19 inside the contact lens type electrode holder 6) is activated by a command from the microcomputer 30.

Note that, here, the left and right noise detection circuits 36a.

36b functions as a noise detection means for detecting noise from the retinal potential amplified by the left and right channel amplifiers 24a and 24b, and the amount of noise detected there (noise level) is set at a predetermined level set by a resistor or the like. Setting value (
It is configured to also function as a first determining means for determining whether the dark value (dark value) is, for example, 50 μv or less, and is less than a predetermined set value determined by the detection circuits 36a and 36b. The time setting circuit 38, which is the second determining means, determines whether or not the amount of noise is maintained for a predetermined time or longer. When measuring the flash ERG, when the amount of noise is below a predetermined set value and maintained for a predetermined time or more, the means for automatically applying optical stimulation is as follows: Here, it is composed of a light stimulation signal trigger output section 40, a microcomputer 30, and a light emitting section 3.

Similar functionality is also applied to flicker-ERG measurements. That is, the LED 19 provided on the contact lens type electrode holder 6 is connected to a predetermined terminal of the device body 1, and a current ON10F controlled based on a command from the microcomputer 30 is connected to the terminal.
The current controlled by the F control circuit 42 is transmitted to the constant current circuit 4
It is designed to be supplied through 4. Note that the constant current circuit 44 connects the LED through the terminal of the device main body 1.
The brightness of the LED 19 is made constant by adjusting the current supplied to the LED 19. Therefore, when measuring flicker ERG, if the amount of noise is below a predetermined set value and maintained for a predetermined time or more, the means for automatically applying optical stimulation is activated by the signal from the time setting circuit 38. , here, the optical stimulation signal trigger output unit 40, the microcomputer 30, and the current ○N/○FF! IJ'4
It is composed of one circuit 42 and a constant current circuit 44.

In short, the above-mentioned optical stimulation automatic start mechanism is activated before such flicker optical stimulation (LED light emission) is applied to the subject.

That is, the left and right noise detection circuits 36a and 36b first determine whether the noise level is below a predetermined set value (noise amount), and then the time circuit setting circuit 38 determines that the set noise level is below a predetermined set value (noise amount).
(level) is maintained for a predetermined time or longer as a second determining means, and inputs the result to the microcomputer 3o from the optical stimulation signal trigger output section 40, so that the microcomputer 3o ,
The LED 19 is activated through the current 0N10FF control circuit 42 and the constant current circuit 44 to generate a predetermined flickering light. However, even in flicker ERG, the potential obtained is weak, so it is important to detect any interfering noise before applying optical stimulation, that is, before starting measurement, and to prevent measurement failures. This is because not only the time is improved, but also the burden on the examinee is reduced.

By the way, FIG. 5 shows the details of the above-mentioned optical stimulation automatic start mechanism in the form of a flowchart.

FIG. 5 shows a state in which preparations for measurement of the subject are completed and the examiner presses the start button 10. First, the amount of noise entering the left and right channel amplification unit from the electrodes attached to the subject is measured by the noise detection unit, and if the amount is less than a set value, the fixation monitor is turned on. The fixation monitors for both eyes turn on, and when this is maintained for a predetermined period of time, a light stimulation signal is output, and then the light emitting unit (xenon lamp 3 or LED 19) is activated to illuminate the subject. It applies light stimulation, detects ERG, and automatically measures (prints out). Although FIG. 5 is a flowchart for binocular measurement, the same applies to monocular measurement.

Through such operations, the action potentials generated in the retina are presented to the examiner in a highly condensed form. In addition, compared to conventional measurement operations that require skill, the examiner simply presses the start button, and the optical stimulation automatic start mechanism inside the device is activated, allowing ERG waveforms to be obtained automatically and with fewer failures. It has become.

Although the embodiments of the present invention have been described in detail above,
It goes without saying that the present invention is not to be construed as being limited only to these specific examples, but the present invention may be modified, modified, improved, etc. without departing from the spirit of the present invention. It should be understood that the present invention includes such embodiments.

For example, in the specific example described above, the fixation monitor as a noise monitor is not essential to the present invention;
Even when performing a light stimulation automatic start operation as in the present invention, there is an advantage that noise information is easier to understand by turning on the light.

Further, in the above example, each of the detection circuits 36a and 36b also serves as a means for determining the amount of noise of each noise, but separately from such a detection circuit, a first determining means for determining the amount of noise is provided. There is no problem with the number of vessels provided, and furthermore, it is also possible to have the first judgment means and the second judgment means serve as both.

Note that the set value (dark value) for determining the amount of noise may be fixedly set using a resistor or the like as shown in the example, or may be variably adjusted using an appropriate setting device. Such a set value is usually set to approximately 50 μV.

Further, the set value by the time setting circuit 38 or the like for determining the amount of noise that is less than or equal to the set value can be set fixedly, but it can also be variably adjusted in stages. The noise level is normally set within a range of approximately 0.1 seconds to 1 second, and the second determination means determines whether the amount of noise is maintained at a predetermined set value or less during the set time. The Rukoto.

Furthermore, it goes without saying that the optical stimulation automatic start mechanism can be configured not only in terms of hardware as in the above example, but also in terms of software.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an example of an electroretinometer according to the present invention, FIG. 2 is an enlarged explanatory diagram of an operating section in such an electroretinometer, and FIG. 3 is a schematic diagram showing an example of an electroretinometer according to the present invention. FIG. 4 is a longitudinal cross-sectional view showing an example of a contact lens type electrode holder used in an electroretinometer, FIG. 4 is a block diagram of such an electroretinometer, and FIG. It is a flowchart showing the operation of the mechanism. 1: Device body 2: Flash box 3: Xenon lamp 4: Fixation lamp 5: Operation unit 6: Contact lens type electrode holder 7: Indifferent electrode 8: Ear electrode 9: Simultaneous monitor 10 Start button 11: Auto/ Manual switching button 12: Flash ERG/flicker - ERG switching 3 ports 13: Lighting button 14: Paper feed button 15: Flash/flicker continuous measurement button 16: Bowl-shaped detection section 17: Main body section 18: Convex lens 19: LED 20: Electrode connection terminals 22a, 22b: isolation amplifiers 24a, 24
b: Amplifier 26: Left and right channel changeover switch 30: Microcomputer 32: Printers 34a, 34b: Input monitors 36a, 36 +: Noise detection circuit 38: Time setting circuit 40: Photostimulation signal trigger output section 42: Current 0N10FF control circuit 44: Constant current circuit Applicant: Toyo Medical Co., Ltd. Kyoto Contact Lens Co., Ltd. Figure 1 Figure 3 U]Z

Claims (5)

[Claims] (1) In an electroretinometer for measuring retinal potential, a predetermined electrode is arranged on the inner concave surface of a bowl-shaped detection part that is attached to the eyeball and touches the corneal surface, and a predetermined electrode is connected to the back of the bowl-shaped detection part. A hemispherical convex lens protruding toward the bowl-shaped detection section that can transmit light incident from the back surface is provided on the main body, and the light passes through the convex lens and contacts the bowl-shaped detection section. A contact lens type electrode holder that is guided to the surface of the cornea; and a contact lens type electrode holder that is positioned behind the electrode holder to generate flash light and irradiate the flash light onto the back surface of the convex lens of the electrode holder. and a flicker light stimulation means comprising a semiconductor light-emitting element disposed near the focal point of the convex lens of the electrode holder to generate flicker light and irradiate it to the bowl-shaped detection part side through the convex lens. and a control device that selectively controls the operation of the flash light stimulation means and the flicker light stimulation means and causes each of the light stimulation means to generate a predetermined light stimulation. (2) an amplifying means for amplifying a retinal potential obtained based on a signal taken out by the electrode of the contact lens type electrode holder; a noise detecting means for detecting noise from the amplified retinal potential; and a noise detecting means for detecting noise from the amplified retinal potential. A first determination means for determining whether the amount of noise detected by the detection means has become equal to or less than a predetermined set value, and whether the time during which the amount of noise is equal to or less than the predetermined set value is maintained for a predetermined time or more. and a second determination means for determining whether or not the noise amount is below a predetermined set value and maintained for a predetermined time or longer, the control device automatically controls the predetermined light stimulation. 2. The retinometer according to claim 1, wherein the electroretinometer is configured to generate . (3) The electroretinometer according to claim 1 or 2, wherein the flash light stimulation means is a xenon flash discharge tube. (4) The retinometer according to any one of claims (1) to (3), wherein the flicker light stimulation means is provided integrally with the convex lens. (5) The retinometer according to claim 4, wherein the flicker light stimulation means is a light emitting diode.