ophthalmic devices

Abstract

To reduce an operation sound and an impact in an ophthalmologic device for measuring an intraocular pressure using a high pressure gas.SOLUTION: An ophthalmologic device includes: a high pressure cylinder 101 for generating a high pressure gas continuously; a pressure accumulation tank 104 for accumulating the high pressure gas supplied from the high pressure cylinder 101; a pressure regulator 103 disposed between the high pressure cylinder 101 and the pressure accumulation tank 104 for supplying high pressure air supplied from the high pressure cylinder 101 to the pressure accumulation tank 104, which is stabilized at a specific pressure; a nozzle 107 connected to the pressure accumulation tank 104 for injecting the high pressure gas to an eye to be examined 200; and an electromagnetic valve 105 disposed between the pressure accumulation tank 104 and the nozzle 107.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an ophthalmic apparatus for measuring intraocular pressure.

Background Art

[0002] A non-contact ophthalmic apparatus is known that measures intraocular pressure by blowing air onto the eyeball and optically measuring the deformation of the eyeball at that time (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In conventional ophthalmic apparatuses for measuring intraocular pressure, a high-pressure gas is generated using a cylinder and blown onto the test eye. This structure has problems such as the operating sound being bothersome to the subject and the impact during operation being bothersome.

[0005] In such a background, the present invention aims to reduce the operating sound and impact in an ophthalmic apparatus that measures intraocular pressure using a high-pressure gas.

Means for Solving the Problems

[0006] The present invention is an ophthalmic apparatus including a high-pressure gas supply means for continuously generating a high-pressure gas, a pressure accumulation tank for storing the high-pressure gas supplied from the high-pressure gas supply means, a pressure stabilization means for setting the internal pressure of the pressure accumulation tank to a specific value, a nozzle connected to the pressure accumulation tank for injecting the high-pressure gas onto the test eye, and a first on-off valve disposed between the pressure accumulation tank and the nozzle.

[0007] In the present invention, an aspect in which the high-pressure gas supply means is a high-pressure cylinder storing a high-pressure gas One embodiment of the present invention is that the high-pressure gas supply means is a pump. In the present invention, one embodiment of the present invention is that the pump generates a high-pressure airflow including a pulsating flow using a diaphragm.

[0008] In the present invention, one embodiment is characterized in which the injection of high-pressure gas into the eye under examination is started by opening the first on-off valve, and the injection of high-pressure gas into the eye under examination is stopped by closing the first on-off valve thereafter.

[0009] In the present invention, a second on-off valve is arranged between the high-pressure gas supply means and the pressure accumulator, and the inside of the pressure accumulator is brought to a specific high-pressure state with the first on-off valve closed and the second on-off valve open, and in that state the second on-off valve is closed, and then the first on-off valve is opened, thereby injecting high-pressure gas from the nozzle into the eye to be examined. [Effects of the Invention]

[0010] According to the present invention, in an ophthalmic device that measures intraocular pressure using high-pressure gas, operating noise and shock are reduced. [Brief explanation of the drawing]

[0011] [Figure 1] This is a conceptual diagram of an ophthalmic device according to an embodiment. [Figure 2] This is a conceptual diagram of an ophthalmic device according to an embodiment. [Figure 3] This is a conceptual diagram of an ophthalmic device according to an embodiment. [Modes for carrying out the invention]

[0012] 1. First Embodiment (composition) Figure 1 shows an ophthalmic device 100 utilizing the invention. The ophthalmic device 100 blows high-pressure air onto the eye 200 under examination, optically detects the degree of deformation of the eye 200 caused by the air pressure, and measures the intraocular pressure of the eye 200. This principle is the same as that of conventional ophthalmic devices.

[0013] The ophthalmic device 100 is equipped with a high-pressure gas supply means, a high-pressure gas cylinder 101, which continuously generates high-pressure gas. Here, high pressure refers to a pressure higher than atmospheric pressure. Compressed air is stored in the high-pressure cylinder 101.

[0014] The high-pressure cylinder 101 is selected to have an internal pressure greater than the maximum internal pressure of the pressure storage tank 104, which will be described later. In this example, the gas stored in the high-pressure cylinder 101 is air, but carbon dioxide gas, nitrogen gas, etc., can also be used.

[0015] For example, the amount of CO2 injected into the eye of a subject using a current intraocular pressure measuring device is approximately 3.3 mL. Based on this, it is estimated that approximately 12,000 injections are possible using a commercially available mini CO2 cartridge (40 mm in diameter, 134 mm in length, 98 ml in capacity, and 41.7 MPa in internal pressure).

[0016] A pressure regulator 103, which is a pressure stabilization means, is connected to the high-pressure cylinder 101 via piping 102. The high-pressure air supplied from the high-pressure cylinder 101 is supplied to the accumulator tank 104 via the pressure regulator 103.

[0017] The pressure regulator 103 has the high-pressure cylinder 101 as the input side and the pressure accumulator tank 104 as the output side. The pressure regulator 103 has the function of keeping the output pressure (internal pressure of the pressure accumulator tank 104) constant under the condition that the input pressure > output pressure. A commercially available pressure regulator 103 is used.

[0018] The accumulator tank 104 stores air at a pressure higher than atmospheric pressure, which is adjusted by the pressure regulator 103.

[0019] The internal volume of the pressure storage tank 104 is set to a volume with sufficient margin with respect to the amount (volume) of air blown from the nozzle 107 onto the test eye 200. In this case, by adjusting the timing of closing the solenoid valve 105, the amount of air blown from the nozzle 107 onto the test eye 200 is adjusted.

[0020] The pressure storage tank 104 has airtightness and is connected to the air chamber 106 via the solenoid valve 105. A nozzle 107 for blowing high-pressure air onto the test eye 200 is connected to the air chamber 106.

[0021] The ophthalmic device 100 has a measurement optical system 108. The measurement optical system 108 includes a light emitting part of measurement light and a light receiving part of reflected light from the test eye 200. The measurement light emitted from the light emitting part in the measurement optical system 108 is irradiated onto the test eye 200 through the light transmission parts 109 and 110, and the reflected light is received by the light receiving part in the measurement optical system 108.

[0022] (Principle of intraocular pressure measurement) While irradiating the test eye 200 with the above measurement light, high-pressure air is blown from the nozzle 107 onto the test eye 200. At this time, the eyeball of the test eye 200 is deformed by the pressure of the high-pressure air. Specifically, the surface of the test eye changes from a convex shape ⇒ flat ⇒ concave shape, and accordingly, the amount of light of the reflected light from the test eye 200 changes.

[0023] <照 Using a standard model eye, the relationship between the change in the amount of light of the above reflected light and the intraocular pressure is obtained in advance, and by applying the change in the amount of light of the reflected light from the actual test eye 200 to this relationship, the intraocular pressure of the test eye 200 is calculated. This is the basic principle of intraocular pressure measurement in the ophthalmic device 100. This is the same as the conventional intraocular pressure measurement

[0024] (Measurement procedure) First, with the solenoid valve 105 closed, high-pressure air is supplied from the high-pressure cylinder 101 to the pressure accumulator 104, and the pressure inside the pressure accumulator 104 is set to a predetermined pressure. This pressure is determined by adjusting the pressure regulator 103. The internal pressure of the pressure accumulator 104 is determined considering the pressure and amount of high-pressure air sprayed from the nozzle 107 onto the eye under examination.

[0025] When the pressure accumulator 104 reaches the specified internal pressure, it becomes possible to spray high-pressure air from the nozzle 107 onto the eye under examination 200. In this state, when the solenoid valve 105 is opened, the high-pressure air in the pressure accumulator 104 moves to the air chamber 106, and high-pressure air is blown onto the eye under examination 200 from the nozzle 107.

[0026] Here, the amount of air ejected from the nozzle 107 is controlled by closing the solenoid valve 105 at the appropriate time. Methods for determining the timing of closing the solenoid valve 105 include closing it after a specified time has elapsed since opening, and closing it based on a change in the intensity of reflected light from the eye 200 under examination. A specific example of the latter method is to optically detect the stage when the surface of the eye 200 under examination becomes flat (when the amount of reflected light is maximum) and close the valve based on that.

[0027] The duration of high-pressure air injection from nozzle 107 is approximately 400 μs to 2000 μs (with a range depending on the pressure). The solenoid valve 105 is selected to enable this opening and closing operation.

[0028] (Superiority) The ophthalmic device 100 includes a high-pressure cylinder 101 that continuously generates high-pressure gas, a pressure accumulator 104 that stores the high-pressure gas supplied from the high-pressure cylinder 101, a pressure stabilization means positioned between the high-pressure cylinder 101 and the pressure accumulator 104 that sets the internal pressure of the pressure accumulator 104 to a predetermined specific pressure, a pressure regulator 103 that supplies the high-pressure air supplied from the high-pressure cylinder 101 to the pressure accumulator 104 in a stabilized state at a specific pressure, a nozzle 107 connected to the pressure accumulator 104 that injects high-pressure gas into the eye 200 under examination, and a solenoid valve 105 positioned between the pressure accumulator 104 and the nozzle 107.

[0029] In this configuration, only the solenoid valve moves when high-pressure air is injected into the eye 200 under examination, thus enabling quiet operation and reduced impact. Furthermore, since vibrations during operation are suppressed, the occurrence of alignment errors, such as the nozzle 107's axis deviating from the eye 200 under examination, is reduced. In addition, while operating noise and impact can cause physiological reactions (such as the subject moving in surprise) and discomfort, these problems are suppressed because the operating noise and impact are reduced.

[0030] Furthermore, because there is no return mechanism present in piston-type systems, the problem of tear droplets being drawn into the nozzle is eliminated. This results in benefits such as suppression of infection and reduced contamination of the nozzle and air chamber. In addition, the absence of mechanical operating mechanisms other than the solenoid valve ensures high reliability. Moreover, the low number of parts allows for a compact overall design. This enables the creation of portable ophthalmic devices.

[0031] As the high-pressure cylinder 101 is used repeatedly, its internal pressure gradually decreases, causing its output characteristics to fluctuate. In this example, by keeping the pressure applied to the accumulator tank 104 constant using the pressure regulator 103, the decrease and fluctuation in output pressure due to the decrease in the internal pressure of the high-pressure cylinder 101 are suppressed from affecting the behavior of the high-pressure air ejected from the nozzle 107.

[0032] 2. Second Embodiment In this example, the volume of the accumulator tank 104 is set to correspond to the amount (volume) of air blown from the nozzle 107 onto the eye 200 under examination. Additionally, a solenoid valve 111 is added between the accumulator tank 104 and the pressure regulator 103.

[0033] An example of the operating procedure in this case is described below. First, with the solenoid valve 105 closed and the solenoid valve 111 open, high-pressure air is sent from the high-pressure cylinder 101 to the pressure accumulator tank 104 via the pressure regulator 103, and the internal pressure of the pressure accumulator tank 104 is set to a predetermined pressure.

[0034] When the internal pressure of the accumulator tank 104 reaches a predetermined pressure, the solenoid valve 111 is closed. After this, the solenoid valve 105 is opened, causing the high-pressure air stored in the accumulator tank 104 to move to the air chamber 106, and the high-pressure air to be ejected from the nozzle 107.

[0035] In this case, the volume and internal pressure of the pressure accumulator 104 are predetermined so that the amount and pressure of air ejected from the nozzle 107 to the outside are specific amounts.

[0036] 3. Third Embodiment It is also possible to use a micropump (microblower) 112 as the source of high-pressure air. The micropump 112 drives a diaphragm with a piezoelectric element, and the movement of this diaphragm discharges gas. Other types of pumps can also be used. It is also possible to use a combination of a pump and a high-pressure cylinder.

[0037] By the way, some micropumps have check valves, while others do not. If a micropump 112 does not have a check valve, a solenoid valve 111 is required. In this case, instead of the solenoid valve 111, a solenoid valve or check valve (not shown) may be placed between the micropump 112 and the pressure regulator 103. If the micropump 112 has a check valve, it is also possible to configure the system without a solenoid valve or check valve between the micropump 112 and the pressure accumulator tank 104.

[0038] The micropump 112 only needs to gradually increase the pressure in the accumulator tank 104 over time, and does not need to pump rapidly. Because rapid pumping is not required, the micropump 112 can be made quieter and operate with reduced shock. Furthermore, a smaller micropump 112 can be used. In addition, since the high-pressure air stored in the accumulator tank 104 is ejected from the nozzle 107 to the eye under examination 200, even if pulsation is generated in the micropump 112, it does not affect the eye under examination 200.

[0039] 4. Fourth Embodiment Figure 2 shows a case where the accumulator tank 104 has a function to maintain a constant internal pressure. In this case, the pressure regulator 103 can be omitted (of course, it can also be used in combination). In this case, the accumulator tank 104 is equipped with a pressure sensor 113 that detects the internal pressure, and a solenoid valve 114 that opens and closes based on the internal pressure of the accumulator tank 104 detected by the pressure sensor 113.

[0040] When high-pressure gas is supplied to the pressure accumulator 104 from a high-pressure gas supply means (high-pressure cylinder 101 or macro pump 112), if the internal pressure of the pressure accumulator 113 is about to exceed a predetermined set value, this is detected by the pressure sensor 113, and the solenoid valve 114 opens. As a result, the internal pressure of the pressure accumulator 113 is released and adjusted so that the internal pressure does not exceed the set value.

[0041] Furthermore, when high-pressure gas is supplied to the accumulator tank 104 from the high-pressure gas supply means and the solenoid valve 114 is open, if the internal pressure of the accumulator tank 104 is about to fall below a predetermined set value, this is detected by the pressure sensor 113, the solenoid valve 114 closes, and the internal pressure of the accumulator tank 104 is adjusted so that it does not fall below a predetermined set value. These adjustments are performed dynamically, thereby maintaining a constant internal pressure in the accumulator tank 113.

[0042] In this configuration, if a micropump 112 without a check valve is used as the high-pressure gas supply means, a solenoid valve 111 (or check valve) is required between the micropump 112 and the pressure accumulator tank 104. If the micropump has a check valve, the solenoid valve 111 is not required. If a high-pressure cylinder 101 is used as the high-pressure gas supply means, the solenoid valve 111 is required.

[0043] 5. Fifth Embodiment A configuration with multiple micropumps is also possible. Figure 3 shows an example of multiple micropumps arranged in series. Note that the parts other than the micropumps are the same as in Figure 1. This embodiment can also be applied to the configuration in Figure 2.

[0044] Figure 3 shows an example of two micropumps 121 and 122 connected in series. By connecting multiple micropumps in series, the pressure of the discharged gas can be increased. Two or more micropumps can be connected in series, and the number should be determined according to the required pressure.

[0045] Furthermore, as shown in Figure 3, multiple micropumps can be arranged in parallel. Figure 3 shows an example in which two micropumps 131 and 132 are connected in parallel. By connecting multiple micropumps in parallel, the flow rate of the discharged gas can be increased.

[0046] Furthermore, as shown in Figure 3, it is also possible to prepare multiple micropumps connected in series and then connect these in parallel. Figure 3 shows examples of micropumps 141 and 142 connected in series, and micropumps 151 and 152 connected in series and then connected in parallel. With this configuration, the pressure and flow rate of the discharged (sent out) gas can be increased. [Explanation of symbols]

[0047] 100...Ophthalmic device for measuring intraocular pressure, 101...High-pressure cylinder, 102...Piping, 103...Pressure regulator, 104...Pressure tank (accumulator), 105...Solenoid valve, 106...Air chamber, 107...Nozzle, 108...Measuring optical system, 109...Light transmission part, 110...Light transmission part, 111...Solenoid valve, 112...Micropump, 113...Pressure sensor, 114...Solenoid valve, 200...Eye under examination, 121...Micropump, 122...Micropump, 131...Micropump, 132...Micropump, 141...Micropump, 142...Micropump, 151...Micropump, 152...Micropump.

Claims

1. A high-pressure gas supply means for continuously generating high-pressure gas, A pressure storage tank for storing the high-pressure gas supplied from the aforementioned high-pressure gas supply means, A pressure stabilization means that sets the internal pressure of the aforementioned pressure accumulator to a specific value, A nozzle connected to the aforementioned pressure tank for injecting high-pressure gas into the eye under examination, A first on / off valve is positioned between the pressure accumulator and the nozzle, A second on / off valve is positioned between the high-pressure gas supply means and the pressure accumulator tank, Equipped with, With the first on-off valve closed and the second on-off valve open, the inside of the pressure accumulator is brought to a specific high-pressure state, and then the second on-off valve is closed, and subsequently the first on-off valve is opened, thereby injecting high-pressure gas from the nozzle into the eye to be examined. Ophthalmology equipment.

2. The ophthalmic apparatus according to claim 1, wherein the high-pressure gas supply means is a high-pressure cylinder storing high-pressure gas.

3. The ophthalmic apparatus according to claim 1, wherein the high-pressure gas supply means is a pump.

4. The ophthalmic device according to claim 3, wherein the pump generates a high-pressure airflow including a pulsating flow using a diaphragm.

5. By opening the first on / off valve, the injection of high-pressure gas into the eye under examination is initiated. The ophthalmic apparatus according to claim 1, wherein the injection of the high-pressure gas into the eye under examination is stopped by closing the first on / off valve thereafter.

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