JP2002263069A - Ocular hardness measuring apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a non-contact type ocular hardness measuring apparatus which can measure ocular tensions and ocular hardness accurately. SOLUTION: The apparatus is provided with an emitter 3 for emitting air fluxes to sites P to be examined of eyes E to be examined, a camera 3 for observing and photographing the sections of the eyes E to be examined and an ocular hardness computing device 4 which calculates the capacity of depressions of the sites P to be examined as caused by air pressures based on the shapes of the sections to compute the ocular tensions and the ocular hardness of the eyes E to be examined based on the capacity of the depressions. The emitter 3 is provided sequentially with a nozzle 10 facing the eyes to be examined, a compressor 11 for sending compressed air to the nozzle 10, a regulator 12 for adjusting the air pressures, an accumulator 13 for accumulating air normalized, a speed controller 14 and a solenoid valve 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an eye hardness measuring device. More specifically, the present invention relates to an ocular hardness measurement device capable of measuring not only intraocular pressure but also ocular hardness of a patient's eye in ophthalmological medicine.

[0002]

2. Description of the Related Art Conventionally, many types of devices for measuring intraocular pressure are known. However, there is no known simple device other than the Shetz tonometer as a simple device that can measure not only intraocular pressure but also intraocular hardness.

The Shetz tonometer has a constant weight of 5.5 g (5 g).
3.9 mN), 7.5 g (73.5 mN), 10 g (9
A load is applied by placing a plunger of 8 mN) or 15 g (147 mN) on the surface of the eye to be examined, and the depth of the depression (recess depth) at this time is enlarged and measured on a scale plate using a lever. Is what you do.

[0004] On the other hand, the relationship between the intraocular pressure corresponding to the depressed volume has been obtained from clinical studies in the past. Therefore, if the depression volume corresponding to the predetermined value load is obtained, the intraocular pressure of the eye to be examined can be obtained. Further, it is possible to approximately calculate the depression volume from the depression depth measured in the subject's eye. A so-called Shetz eye showing the relationship between the intraocular pressure obtained based on the calculated depression volume and the numerical value of the scale (corresponding to the depression depth and corresponding to the depression volume). A manometer conversion table has been created.

Accordingly, the Shetz tonometer obtains a depression volume corresponding to a desired intraocular pressure by using a scale (an enlarged representation of the depression depth) as an index. The intraocular pressure of the subject's eye can be obtained using the above-mentioned Shetz tonometer and the Shetz tonometer conversion table. It is said that intraocular pressure and resistance of the eyeball capsule are important factors in measuring intraocular pressure, and it is known that intraocular pressure is greatly affected by intraocular hardness. If you do not know the intraocular hardness, you may mistake the true intraocular pressure. It is said that eye hardness is particularly important for myopic eyes. Shetz's tonometry is based on the following theoretical formula:

Where P is the intraocular pressure of the eye under the load, V is the depressed volume of the eye under the load, K is a constant called ocular rigidity, and C is Is a constant.

[0007] A known technique for measuring ocular hardness using a Shetz tonometer is as follows. If two types of loads are used for one eye to be examined, the above-mentioned two theoretical formulas can be obtained as follows.

Log P ₁ = C + KV ₁ log P ₂ = C + KV ₂ P ₁ is the intraocular pressure when the first load is applied, V ₁ is the concave volume at that time, and P ₂ is the second load. It is the intraocular pressure when applied, and V ₂ is the concave volume at that time.

From these two formulas, the eye hardness K is obtained as follows.

K = logP ₂ −logP ₁ / V ₂ −V _{1 In the} state where no load is applied, that is, the intraocular pressure in the natural state has been measured in the past corresponding to the measurement results by the above two types of loads. .

There is also a conversion table in which the eye hardness and intraocular pressure are summarized for two types of loads. It is measured with a Shetz tonometer, and then the conversion table can be used to obtain intraocular pressure and ocular rigidity.

The above description is based on known literature (eg, Ophthalmic Moo).
k, No. 3, 1978, "Intraocular pressure test" in "General ophthalmic examination" published by Kanehara Publishing.

[0013]

However, as described above, the Shetz tonometer is a so-called contact-type measuring instrument in which the plunger is brought into direct contact with the eye to be examined. In the case of the contact type, the subject may cause fear and pain, and the measurement may not be performed well. For this reason, in order not to damage the eye to be examined, it is necessary to perform a preparatory treatment on the subject prior to the measurement, and it is necessary to carefully handle the measuring instrument.

As a result, there is a problem that the preparation work for measurement and the measurement work themselves take time and costs are high.

In order to obtain intraocular pressure from the depression volume, the Shetz tonometer visually confirms a scale as an index. However, there is also a problem that the pointer vibrates and is difficult to read accurately because of the contact type.

The present invention has been made in order to solve such problems, and an object of the present invention is to provide an eye hardness measuring apparatus which does not need to be brought into contact with a subject's eye when measuring intraocular pressure and eye hardness.

[0017]

According to the present invention, there is provided an ocular hardness measuring apparatus for observing a cross section of a portion of an eye to be examined from which the above-mentioned air flux has been ejected. The optical system includes a cross-section observation optical device and an eye-hardness calculating unit that calculates the eye hardness of the subject's eye based on the shape of the cross-section.

According to such a measuring device, a part of the eye to be inspected can be depressed by the emitted air flux without having to bring the device into contact with the eye to be inspected. Moreover, since the cross section of the depressed portion can be grasped by the optical system,
It becomes possible to more accurately obtain the depressed volume required for calculating intraocular pressure and eye hardness. As a result, when the conventional conversion table is used, it becomes possible to accurately match the depression volume of the conversion table as compared with the conventional Shetz tonometer, and it is possible to know an accurate intraocular pressure.

The air bundle ejecting means is a measuring device comprising an air nozzle capable of facing the eye to be examined and an air pumping device for ejecting air having different pressures at different times through the air nozzle. In this case, since the air ejection nozzle is used, a load can be applied to the subject's eye in a predetermined small area range similar to the conventional contact of the plunger. In addition, since it is easy to control the air bundles having different pressures to be ejected at different times, it is possible to complete the operation for obtaining the eye hardness in a short time.

In this measuring device, the air pumping device includes an air pressurizer that compresses and feeds air, a first air pressure stabilizing device that adjusts the air pressure to be sent, and a second air pressure device that stores the stabilized air. In the measuring device provided with the single pressurizer and the first on-off valve toward the air nozzle in the above order, the air sent from the air pressurizer was set to a constant pressure by the first air pressure stabilizing device. Is stored in the first compressor.
As a result, the air flow is injected through the air nozzle by opening the first on-off valve, but during this injection, the air pressure is not easily reduced due to the presence of the first compressor. Therefore, a fixed load can be applied to the eye to be examined in the same manner as when the plunger is placed on the eye to be examined.

In this measuring device, the pneumatic feeding device branches off downstream of the air pressurizer and then adjusts the air pressure to be sent, and the second pneumatic steadying device for storing the stabilized air. A pressure regulator and a second on-off valve are provided in the above order toward the air nozzle, and are configured to merge downstream of the first on-off valve between the second on-off valve and the air nozzle. In, for example, if the installation pressure values of the first air pressure stabilizing device and the second air pressure stabilizing device are changed, and if the opening time of the first on-off valve and the second on-off valve is different, Air fluxes of two different pressures can be ejected at different times without the need for air pressure. As a result, eye hardness can be obtained.

[0022] Further, the measuring device having an air flow regulator between the first accumulator and the first on-off valve and / or between the second accumulator and the second on-off valve in the air pressure feeding device. In this case, a constant load acts on the subject's eye because the amount of emitted air is kept constant. That is, similar to the mounting of the conventional plunger, a certain depression is generated in the eye to be inspected, so that the measurement is easy.

Alternatively, the cross-section observation optical device includes a slit light irradiating unit that irradiates a slit light to a portion of the eye to which the air beam is emitted, and a light receiving unit that receives the slit light reflected by the eye to be inspected. The measuring device provided is preferable because the surface shape of the depressed portion can be obtained by the injection of the air flux, so that the depressed volume can be easily obtained as compared with the related art.

Alternatively, in the measuring apparatus, wherein the eye hardness calculating means includes calculating means for calculating the concave volume based on the obtained concave shape of the surface of the eye in the cross section, This is preferable because the concave volume can be easily and accurately calculated.

Alternatively, in a measuring apparatus in which the air bundle ejecting means is controlled so as to eject air having different pressures at different times through the air nozzle, data for obtaining ocular rigidity can be easily obtained. Since there is no need to provide a plurality of air injection systems in accordance with the difference in pressure, the entire apparatus can be made compact.

The above-mentioned ocular hardness measuring device having an air pressurizer, a first air pressure stabilizing device, a first compressor, and a first on-off valve, further comprising an injection control device, One of the on-off valves has a switchable exhaust port, the injection control device changes the set pressure of the first pneumatic pressure stabilization device, and opens, closes, and exhausts the first on-off valve. In the measuring device configured to control the switching of the air pressure, the injection air pressure can be changed by the injection control device, and when the air bundle is injected at the wrong time, the first on-off valve can By once evacuating the air from the accumulator, an air bundle with an accurate pressure can be ejected.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an eye hardness measuring apparatus according to the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing a schematic configuration of an eye hardness measuring apparatus according to one embodiment of the present invention.

The measuring device 1 shown in FIG. 1 includes an eye observation / photographing device (hereinafter, referred to as a photographing device) 2, an air beam ejecting device (hereinafter, referred to as an ejecting device) 3, and an eye hardness calculating device (hereinafter, a computing device). 4 is provided.

The photographing device 2 is a cross-sectional observation photographing optical device (hereinafter, referred to as a cross-section) for observing and photographing a cross section of a part to be measured of the eye E to be examined.
A photographing optical device) 5 and a photographing control device 6 for performing position adjustment and timing adjustment for photographing this section.
And

The photographing control device 6 stores an alignment control unit 7 for positioning the photographing optical device 5 with respect to the region to be inspected of the eye to be inspected, and a cross-sectional image of the region to be inspected observed by the photographing optical device 5. An image memory 8 and a measurement control unit 9 for measuring the timing of emission of illumination light and emission of air flux for photographing based on the cross-sectional image.

The air-flux injection device 3 includes a nozzle 10 for directing the air-flux to the eye E, a compressor 11 for pressurizing the air sent to the nozzle 10, and a constant pressure of the pressurized compressed air. Regulator 12, an accumulator 13 for storing the air depressurized to a constant pressure by the regulator 12, a speed controller 14 for adjusting the flow rate of the air flow from the accumulator 13,
An electromagnetic on-off valve 15 for circulating and closing the air flow sent to the nozzle 10 and an injection control device 16 for controlling the pressure of the regulator 12 and controlling the opening and closing of the electromagnetic on-off valve 15 and exhaust are provided. This is the basic configuration.

FIG. 2 shows an example of the air bundle injection device 3 in detail. This air bundle injection device 3 further includes
A mist separator 35 for removing moisture in compressed air is provided in a pipe between the compressor 11 and the regulator 12.
And the tank 36 are arranged in that order. Pressure detectors 37 and 38 are provided between the regulator 12 and the accumulator 13 and at the base of the nozzle 10, respectively. As the regulator 12, a so-called electro-pneumatic regulator capable of controlling a set pressure by an electric signal from the injection control device 16 is used. The regulator 12 is used to measure intraocular pressure and ocular rigidity, for example, to set two types of pressures, high pressure and low pressure, respectively. An exhaust port 15 a is formed in the electromagnetic on-off valve 15, and is configured to switch between valve opening, valve closing, and exhaust to the outside by an electric signal from the injection control device 16.

The electromagnetic on-off valve 15 is normally closed, and all the devices from the compressor 11 to the electromagnetic on-off valve 15 are open, and the internal space is in communication. Therefore, when the compressed air is sent toward the nozzle 10 by the compressor 11, the compressed air is reduced to a predetermined pressure by the regulator 12, and then is filled into the piping up to the electromagnetic on-off valve 15 including the accumulator 13 and the inside of the device. The discharge pressure of the compressor 11 is set higher than the settable pressure range of the regulator 12. The accumulator 13 is a large-volume portion formed in, for example, a tank shape in a pipe between the regulator 12 and the speed controller 14, and has an action of preventing the pressure of the ejection air pressure from dropping due to the ejection of the air bundle from the nozzle 10. .

By disposing the tank 36, when the set pressure of the regulator 12 is changed from low pressure to high pressure, air having a pressure higher than the set pressure of the regulator 12 is waiting in the tank 36. Therefore, the preparation time for the change is reduced.

By installing and controlling the speed controller 14, fluctuations in the pressure of the air flux emitted from the nozzle 10 can be prevented. In other words,
The injection pressure becomes constant over time.

By setting the upstream pressure detector 37, the set pressure of the regulator 12 can be confirmed. Also, by installing the downstream pressure detector 38,
The pressure of the air bundle ejected from the nozzle 10 can be confirmed. The injection control device 16 can change the set pressure of the regulator or stop the operation according to the confirmation result. Further, the air pressure load applied to the eye to be examined can be known by using these pressure detectors 37 and 38.

As shown in FIG. 3, prior to use of the injection device 3, a predetermined distance from the tip of the nozzle 10 (substantially equal to the distance between the tip of the nozzle and the part to be inspected when actually measuring intraocular pressure or the like). The calibration pressure sensor S is disposed at a position separated by a distance of about 11 mm in this embodiment, and the pressure distribution in the calibration pressure sensor S is measured by ejecting an air flux. The load is obtained from the measured pressure distribution by integration. The relationship between the load obtained by the calibration pressure sensor S and the pressure detected by at least one of the pressure detectors 37 and 38 is stored in a memory in the arithmetic unit 4 described later. Then, from the pressures detected by the pressure detectors 37 and 38, it is possible to know the load and the pressure receiving area that are actually applied to the test portion P by the emitted air flux.

The arithmetic unit 4 shown in FIG. 1 calculates an image processing unit 17 for image processing the photographed cross-sectional image, and calculates a depressed volume of the eye to be examined using the image processed information. A calculation unit 18 for calculating the intraocular pressure and the ocular rigidity of the subject's eye using the volume. This arithmetic unit 18 includes:
Although not shown, a first memory that stores a program for the above calculation, a pressurization of the eye to be examined by air pressure and a depressed volume due to this, and a second memory that stores information such as intraocular pressure corresponding to the depressed volume A memory and a CPU that executes the arithmetic program are stored.

In the arithmetic unit 4, a predetermined air load applied to the subject P of the subject's eye by the injection air obtained by the injection device 3 and the air load obtained by the photographing device 2 are used. Based on the cross-sectional image of the depressed test part and the cross-sectional image in an unloaded state (a state in which no air load is applied), the intraocular pressure of the eye to be inspected and the eye using the above information such as the intraocular pressure corresponding to the depressed volume Calculate the hardness. That is,
The cross-sectional image photographed by the photographing device 2 is sent to the image processing unit 17 of the arithmetic device 4, where it is subjected to image processing to calculate the depression volume. Then, the depression volume is accurately calculated. Based on the information such as the intraocular pressure stored in the memory, the corresponding intraocular pressure is calculated from the depressed volume, and the intraocular hardness and intraocular pressure specific to the eye to be examined are calculated by the following equations.

LogP ₁ = C + KV ₁ logP ₂ = C + KV ₂ K = log P ₂ −log P ₁ / V ₂ −V ₁ As described above, P ₁ and V ₁ are intraocular pressure and depression due to the first load (for example, high pressure load). P ₂ and V ₂ are the intraocular pressure and the depression volume due to the second load (for example, low pressure load). K is eye hard.

As described above, an important effect of the use of the present apparatus 1 is that an accurate intraocular pressure and eye pressure can be obtained by using a conventional Shetz conversion table and making it correspond exactly to the depressed volume displayed therein. Hardness can be obtained. This conversion table is stored in the memory so that the depression volume and the corresponding numerical values of intraocular pressure and ocular rigidity can be continuously specified by a simple mathematical formula.

FIG. 4 shows the photographing optical device 5. The photographing optical device 5 includes an illumination optical system 21 for illuminating a portion (hereinafter, referred to as an object to be inspected) P of the eye E to be inspected from the oblique front with slit light,
A photographing optical system 22 for photographing slit light from the illumination optical system 21 reflected by the subject P, and an alignment index for photographing optical axis alignment (alignment) toward the anterior segment of the subject's eye E An alignment optical system 23 for irradiating light from the front and capturing the reflected light of the cornea, and a focusing optical system 24 for matching the focal point of the photographing optical device 5 to the corneal endothelium, which is the region to be photographed. ing.

The illumination optical system 21 has a strobe discharge tube (xenon tube) 25 as an illumination light source. The imaging optical system 22 has a measurement camera 26. The alignment optical system 23 has a light emitting diode 27 as a light source of the alignment index light and a television camera 28. The focusing optical system 24 includes a focusing lamp 29. The alignment index light and the focusing light are both near-infrared light, and the illumination light for photographing (measurement) is visible light.

In the drawing, reference numeral 30 denotes a slit, reference numeral 31 denotes an illumination lens, reference numeral 32 denotes an objective lens, reference numeral 33 denotes a beam splitter, and reference numeral 34 denotes a half mirror that transmits infrared light and reflects visible light. The measuring camera 26 is also used for detecting the focal point by the focusing optical system 24.

On the optical axis F between the eye E and the television camera 28 in the alignment optical system 23, the nozzle 10 of the air bundle ejecting device 3 is disposed in close proximity to the eye E. . Since the nozzle 10 is supported by the support member 10a formed of a transparent material, it does not block light. Further, the nozzle 10 itself may be formed from a transparent material.

In the alignment optical system 23, near-infrared light from the light-emitting diode 27 is applied to the anterior segment of the eye E from the front, and a luminescent spot (Purkinje image) as a reflection image of the light on the surface of the eye E ) Is sent to the television camera 28.
The alignment control unit 7 determines that the Purkinje image is
The driving mechanism 7a is instructed to move the photographing optical device 5 in the X direction and the Y direction so as to reach the vertex. That is,
By moving the optical axis F in the direction perpendicular to the axis toward the corneal vertex of the eye to be examined, the optical axis F coincides with the vertex of the eye E to be examined.

In the focusing optical system 24, the focus detecting slit light from the focusing lamp 29 reaches the eye E along the optical axis of the illumination optical system 21 and is reflected by the anterior eye to be measured by the measuring camera. The light is received at 26.

As shown in FIG. 5, by moving the photographing optical device 5 back and forth in the direction toward the eye to be inspected (Z direction), the light receiving portion of the measuring camera 26 is reflected by the slit light (the optically cut image of the surface of the eye to be inspected). ) G moves left and right. This is because the reflection position of the slit light moves in the subject's eye. Then, the photographing optical device 5 is moved in the Z direction so that the reflected slit light G comes to a predetermined focus position on the light receiving section of the measuring camera 26. This is the focusing operation. This in-focus position corresponds to the in-focus point of the photographing optical system 22 as a matter of course. That is, the focus of the photographing optical system 22 is set to the above-mentioned focal point. The optical axis F of the alignment optical system 23 is also configured to pass through the focal point.

Then, the measurement controller 9 based on the photographed image
By moving the imaging optical device 5 toward and away from the eye to be inspected (Z direction in FIG. 2) based on the signal from the camera, the focal point is aligned with the imaging region of the eye E. This alignment is called focusing. In general, focusing is performed simultaneously with alignment.

At the time when the alignment and focusing are both performed, the measurement control unit 9 causes the strobe discharge tube 25 to emit light, and the portion to be inspected P is photographed. Immediately before photographing, the nozzle 1 is controlled by the measurement control unit 9 as described later.
From 0, air is continuously emitted to the eye E to be examined. Therefore, a cross section of the test portion P of the subject's eye E that is depressed by the ejection of air is photographed. That is, since the slit light which is obliquely incident on the concave portion P and reflected on the surface of the concave portion P is received obliquely and photographed, the cross section of the concave portion P is photographed. The photographed cross-sectional image is sent to the image processing unit 17 of the arithmetic unit 4, where it is subjected to image processing to calculate the depression volume.

The operation of the measuring device 1 configured as described above will be described.

Normally, the surface of the test part in a natural state as a reference is photographed without pressurization by air flux injection (no load state), and in addition, a load due to high pressure (high pressure load) and a load due to low pressure (low pressure) (Load) is performed twice by injecting air bundles of two types of pressures. The high pressure load and the low pressure load are loads caused by air pressure applied to the test portion P. In the present embodiment, for example, the low pressure load is 5.5 g (53.9 mN), and the high pressure load is 7.5 g (73.5 mN). ) And low pressure load of 10g
(98 mN) and the case where the high pressure load is 15 g (147 mN). Of course, a pressure other than the above may be set.

First, the tip of the nozzle 10 of the measuring apparatus 1 is brought close to the part P of the eye E at a predetermined distance. And
When the measurement operation is started, the compressor 11 operates to send compressed air toward the nozzle 10. The compressed air is reduced in pressure to an internal pressure corresponding to a predetermined high pressure load by the regulator 12, and the compressed air is supplied from the regulator 12 to the electromagnetic on-off valve 15.
Fill up to the inside of piping and equipment. In other words, it is in a standby state.

Next, when the photographing start button of the device 1 (not shown) is turned on, the photographing device 2 operates to perform alignment and focusing operations on the subject's eye. At the time when the alignment and focusing operations are performed, imaging is performed without load. In other words, the reference plane is specified. FIG. 6A shows an example of an image G of the test portion P taken under no load.

Immediately after the photographing, the injection device 3 is operated to open the electromagnetic on-off valve 15 and to wait for the pressurized state to stabilize, it is slightly delayed from the start of the valve opening (about 15/1000).
(Second later) The stroboscopic discharge tube 25 of the photographing device 2 emits light, and the portion to be inspected P is photographed. This is a photograph taken with a high pressure load. Of course, light emission of the strobe discharge tube 25 is performed while the air flux is being emitted. FIG. 6B shows an example of an image G of the test portion P taken by a high-pressure load.

When the photographing is completed, the apparatus returns to the standby state again. During this time, the set pressure of the regulator 12 is switched to the constant internal pressure corresponding to the low-pressure load, and the electromagnetic on-off valve 15 is switched to the exhaust mode by the re-imaging signal from the injection control device 16. And
When the pressure detected by the upstream pressure detector 37 becomes the internal pressure corresponding to the low pressure load, the electromagnetic on-off valve 15 is closed.

Then, when the photographing start button is turned on again, the alignment operation and the focusing operation are performed again. Then, photographing is performed again with no load. Re-identification of the reference plane.

Next, the high-pressure load is photographed by the low-pressure load in the same order as described above. FIG. 6C shows an example of an image G of the test portion P taken by a low pressure load. The pressure value in the apparatus and the image information at the time of the two shootings are sent to the arithmetic unit 4. The arithmetic unit 4 performs image processing to calculate the depressed volume of the test portion. That is, as shown in FIG. 6D, the concave cross-sectional area A is obtained from the reference surface of the test portion at the time of no load and the surface of the test portion at the time of the depression, and the volume at the time of rotation around the central axis L is obtained. (Recess volume) is determined. Further, a high-pressure load and a low-pressure load corresponding to the depression volume are specified from the pressure in the device. Then, the intraocular pressure and the stiffness of the subject's eye are calculated from the high pressure load and the low pressure load and the corresponding depression volume.

In the above description, the photographing was first performed with the high pressure load from the viewpoint of the efficiency of the step-up operation in the apparatus. However, the operation order is not particularly limited. The photographing with a low pressure load may be performed first.

The injection device 3 shown in FIG. 2 has only one system of the pneumatic feed line and switches the injection pressure by the injection control device 16, but the present invention is not limited to such a configuration. In order to eject air bundles of different pressures, a pneumatic feed line may be provided for each injection pressure.

The injection device 41 shown in FIG. 7 is provided with a pneumatic pressure feed line such as a double system. High pressure line (first line) 41
a and the low pressure line (second line) 41b. In this injection device 41, each single compressor 11
The mist separator 35 and the downstream pressure detector 38 are also used for both air pressure feed lines 41a and 41b. From the outlet of the mist separator 35, the pipe is divided into both lines.

The first line includes a first regulator 12 which is set to an internal pressure (high pressure) corresponding to the high pressure load.
, The first upstream pressure detector 37 and the first accumulator 1
3, a first speed controller 14, and a first solenoid on-off valve 15 are arranged in that order.
A second regulator 42 set to an internal pressure (low pressure) corresponding to the low pressure load, a second upstream pressure detector 47, a second accumulator 43, and a second speed controller 4
4 and a second solenoid on-off valve 45 are arranged in that order.

Prior to the measurement of the intraocular pressure or the like, the pressure between the first regulator 12 and the first solenoid on-off valve 15 in the first line 41 a is increased by the first regulator 12 to the high pressure, and the second regulator 42 increases the pressure. Line 4
1b, the second regulator 42 and the second solenoid valve 4
The pressure between 5 and 5 is kept at the above low pressure.

When measuring the intraocular pressure or the like, the subject is first photographed in a no-load state, and subsequently, the first solenoid valve 15 is turned off.
Is opened for a predetermined time, and a high pressure load is applied to the eye to be inspected to photograph the portion to be inspected. Next, imaging is performed again with no load, and subsequently, the second electromagnetic opening / closing valve 45 is opened for a predetermined time, and a low-pressure load is applied to the eye to be inspected to image the portion to be inspected. Then, the intraocular pressure and the eye hardness are calculated as described above.

Of course, the setting of pressure, the timing of opening and closing the electromagnetic on-off valve, and the like are controlled by an injection control device (not shown).

As described above, the provision of the pneumatic feed lines of the two systems or the like makes it possible to continuously perform photographing with a high pressure load and a low pressure load, thereby shortening the entire measurement time.

[0068]

According to the eye hardness measuring apparatus of the present invention, a part of the eye to be examined can be depressed by the emitted air flux without the need to bring the apparatus into contact with the eye to be examined. Moreover,
Since the cross section of the depressed portion can be grasped by the optical system, it is possible to more accurately obtain the depressed volume required for calculating the intraocular pressure and the stiffness of the eye.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration of an eye hardness measurement apparatus according to an embodiment of the present invention.

FIG. 2 is a side view schematically showing an example of an injection device in the eye hardness measurement device of FIG.

FIG. 3 is a side view schematically showing a technique for measuring a pneumatic load by an air bundle ejected by the eye hardness measuring device of FIG. 1;

FIG. 4 is a side view schematically showing an example of a photographing optical device in the eye hardness measurement device of FIG. 1;

FIG. 5 shows a state during a focusing operation of the eye hardness measuring apparatus of FIG.
It is a figure showing the section picture of the to-be-tested part which received light.

6 shows a cross-sectional image of a portion to be inspected during a photographing operation of the eye hardness measuring apparatus of FIG. 1, FIG. 6 (a) shows a cross-sectional image in a no-load state, and FIG. FIG. 6C shows a cross-sectional image at the time of low pressure load, and FIG.
(D) shows an image in a non-loaded state and an image in a loaded state combined.

FIG. 7 is a side view schematically showing another example of the injection device in the eye hardness measurement device of the present invention.

[Explanation of symbols]

 Reference Signs List 1 eye hardness measurement device 2 imaging device 3 injection device 4 arithmetic device 5 imaging optical device 6 imaging control device 7 alignment control unit 8 image memory 9 measurement control unit 10 nozzle 11 compressor 12 regulator 13 accumulator 14 speed controller 15 electromagnetic on-off valve 16 injection Control device 17 Image processing unit 18 Arithmetic unit 21 Illumination optical system 22 Imaging optical system 23 Alignment optical system 24 Focusing optical system 25 Strobe discharge tube 26 Measurement camera 27 Light emitting diode 28 TV camera 29 Focusing lamp 30 Slit 31 Illumination lens 32 Objective Lens 33 Beam Splitter 34 Half Mirror 35 Mist Separator 36 Tank 37 (First) Upstream Pressure Detector 38 (First) Downstream Pressure Detector 41 Injection Device 41a First Line 41b Second Line 42 Second Regulator 43 Second accumulator 44 Second speed controller 45 Second solenoid on-off valve 47 Second upstream pressure detector E Eye to be examined F Optical axis G Slit light (image of the part to be inspected) P Part to be inspected S Pressure sensor for calibration

Claims (10)

[Claims] 1. An air beam emitting means for emitting an air beam to the surface of an eye to be inspected, a cross-section observation optical device for observing a cross section of a portion of the eye to which the air beam is emitted, and a shape of the cross section And an eye hardness calculating means for calculating the eye hardness of the eye to be examined. 2. The air bundle ejecting means comprises an air nozzle capable of facing an eye to be examined, and an air pumping device for ejecting air having different pressures at different times through the air nozzle.
The eye hardness measurement device according to the above. 3. An air compressor for compressing and sending air toward the air nozzle, a first air pressure stabilizing device for adjusting the air pressure to be sent, and storing the stabilized air. The ocular rigidity measuring device according to claim 2, further comprising: a first accumulator that performs the operation; and a first on-off valve. 4. A second pneumatic pressure stabilizing device for adjusting air pressure to be sent toward an air nozzle after branching downstream of the air pressurizer, wherein the air pressure feeding device stores the stabilized air. 4. The apparatus according to claim 3, further comprising a second compressor and a second on-off valve in that order, wherein the second on-off valve and the air nozzle are configured to merge downstream of the first on-off valve between the second on-off valve and the air nozzle. 5. Eye hardness measurement device. 5. Between the first accumulator and the first on-off valve,
4. The eye hardness measuring device according to claim 3, further comprising a first air flow regulator for adjusting a flow rate of the air flow from the first compressor. 6. Between the second accumulator and the second on-off valve,
5. The eye hardness measurement device according to claim 4, further comprising a second air flow rate adjuster that adjusts a flow rate of the air flow from the second compressor. 7. The cross-section observation optical device includes: a slit light irradiating unit configured to irradiate a slit light on a portion of the eye to which the air flux is emitted; and a light receiving unit configured to receive the slit light reflected by the eye. The eye hardness measurement device according to claim 1, further comprising: 8. The ocular rigidity measurement according to claim 1, wherein the ocular rigidity calculating means includes a calculating means for calculating the concave volume based on the obtained concave shape of the surface of the eye to be examined in the cross section. apparatus. 9. The ocular hardness measuring apparatus according to claim 1, wherein the air bundle ejecting means is controlled so as to eject air having different pressures at different times through the air nozzle. 10. An injection control device, further comprising: a switchable exhaust port for the first opening / closing valve; wherein the injection control device changes a set pressure of the first pneumatic pressure stabilizing device; 5. The eye hardness measuring apparatus according to claim 4, wherein the apparatus is configured to control switching of the first on-off valve between opening and closing and exhaust.