JP3461939B2 - Non-contact tonometer fluid pressure testing device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid pressure inspection device for inspecting fluid pressure of a non-contact tonometer.

[0002]

2. Description of the Related Art Conventionally, there is known a non-contact tonometer that obtains intraocular pressure from the fluid pressure when a fluid is ejected to the cornea of an eye to be inspected to form the cornea into a predetermined shape. In this type of non-contact tonometer, it is necessary to know the pressure of the fluid accurately, and the pressure is adjusted before shipping. As an apparatus for inspecting the pressure of ejected fluid, an inspection apparatus having a configuration as shown in FIG. 4 is known.
Reference numeral 60 is a plane mirror that receives fluid ejected from the nozzle 70 of the non-contact tonometer. The plane mirror 60 is attached to the tip of the needle bar 61, and the needle bar 61 is attached to the pivot shaft 62. A spiral spring 63 is provided on the pivot shaft 62, and the spring force of the spring 63 is adjusted by turning a rotation adjusting knob 64. 65 is a balance.

The fluid pressure test is carried out by first aligning the non-contact tonometer with the mirror 60 and then measuring the balance 65.
The weight 66 is hung on the hook 65c. When the weight 66 is hung, the balance 65 rotates in the direction of arrow A about the shaft 65a as a center of rotation, and the downwardly extending leg 65d pushes the upper end portion of the needle bar 61, so that the needle bar 61 moves in the direction of arrow B based on the pivot shaft 62. Rotate in the direction of and tilt. Subsequently, the rotation adjusting knob 64 is turned to adjust the helical spring 63 so that the needle bar 61 is perpendicular to the axis L of the nozzle 70. The spring force in this state corresponds to a predetermined intraocular pressure value. After that, when the balance 65 is retracted in the direction of arrow C, the needle bar 61 is moved to the adjusted spring 63.
Is tilted by rotating in the direction opposite to the arrow B by the spring force. When an airflow is blown from the nozzle 70 toward the tilted mirror 60, the mirror 60 rotates in the direction of arrow B. Mira-60
When is perpendicular to the axis L, the light receiving system 72 that receives the measurement light reflected by the mirror 60 shows the maximum amount of received light.
This tests the fluid pressure of the non-contact tonometer.

[0004]

However, the fluid pressure inspection device as described above has an extremely complicated structure,
Since the force applied to the plane mirror is only a few grams, it requires very precise adjustment. In addition, the handling of the device was very difficult and inconvenient.

The present invention has been devised in view of the above-mentioned drawbacks of the conventional device, and it is an object of the present invention to provide a fluid pressure inspection device for a non-contact tonometer which has a simple structure, requires no troublesome adjustment, and is easy to handle. This is a technical issue.

[0006]

In order to solve the above problems, the present invention is characterized by having the following configuration. (1) by ejecting fluid from nozzles onto the cornea, the fluid pressure inspection apparatus for inspecting a fluid pressure of the non-contact tonometer to obtain intraocular pressure from the fluid pressure when deformed into a predetermined shape, the An opening slightly larger than the nozzle diameter is provided.
Has a closed internal space, and is connected from the nozzle of the non-contact tonometer
The fluid receiving part that receives the ejected fluid and the ejected from the nozzle
Pressure detection means for detecting the pressure of the fluid in the fluid receiving portion ,
Selection means for selecting the test pressure, the pressure detecting means selection
Transmitting means for transmitting a detection signal to the non-contact tonometer when the fluid pressure corresponding to the examination pressure selected by the selecting means is detected, and an angle at the time of measuring the fluid pressure of the non-contact tonometer
It is characterized by inspecting at the membrane position .

(2) A fluid is jetted to the cornea of the eye to be examined.
And obtain the intraocular pressure from the fluid pressure when deformed into a predetermined shape
Fluid pressure inspection device for inspecting the fluid pressure of a non-contact tonometer
In, detecting the fluid pressure of the non-contact tonometer
Pressure detection means and pressure setting means for setting the pressure to be inspected
And a fluid corresponding to the pressure set by the pressure detecting means.
When the pressure is detected, a detection signal is sent to the non-contact tonometer.
And a transmitting means for transmitting the non-contact intraocular pressure.
A light source that emits light toward the light detection means that detects the deformation state of the meter.
Characterized by being a means of conduct

(3) A fluid is jetted to the cornea of the eye to be examined.
And obtain the intraocular pressure from the fluid pressure when deformed into a predetermined shape
Fluid pressure inspection device for inspecting the fluid pressure of a non-contact tonometer
In, detecting the fluid pressure of the non-contact tonometer
Pressure detection means and pressure setting means for setting the pressure to be inspected
And a fluid corresponding to the pressure set by the pressure detecting means.
When the pressure is detected, a detection signal is sent to the non-contact tonometer.
Transmission means and the alignment light of the non-contact tonometer
And a reflecting plate that reflects the light .

[0009]

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a non-contact tonometer 1 and a fluid pressure test device 40.
FIG. 2 is a diagram showing the configuration of FIG. 2, and FIG. 2 is an enlarged view of a main part thereof. As a premise of the description of the fluid pressure inspection device 40, first, the configuration of the non-contact tonometer 1 will be briefly described.

<Non-contact Tonometer> (Fluid ejection mechanism) 2 is a piston, and the piston 2 is driven by a solenoid 3 to reciprocate in a compressed air chamber 4. The compressed air is jetted from the nozzle 5. Reference numeral 6 is a pressure sensor that detects the pressure in the compressed air chamber 4.
Reference numerals 7 and 8 denote transparent glass plates, which hold the nozzle 5 and transmit observation light and alignment light, and also serve as side walls of the compressed air chamber 4. Reference numeral 9 denotes a transparent glass plate provided on the back surface of the nozzle 5, which constitutes a rear wall of the compressed air chamber and transmits observation light and alignment light.

(Optical system) L indicates the optical axis of the observation optical system,
It coincides with the axis of the nozzle 5. On the optical axis L behind the glass plate 9, a half mirror 10, an objective lens 11, and a half lens
The Fumilla-12, the imaging lens 13, and the image pickup device of the television camera 14 are sequentially arranged. A collimating lens 15 and an alignment LED 16 for emitting near-infrared light are arranged on the reflection side of the half mirror 10. A condenser lens 17, a field stop 18, and a photodetector element 19 are sequentially arranged on the reflection side of the half mirror 12. When the eye to be inspected is placed in front of the nozzle 5, the alignment light emitted from the LED 16 is collimated by the collimating lens 15 and then reflected by the half mirror 10 in the optical axis direction. The alignment light reflected by the half mirror 10 passes through the glass plate 9 and the nozzle 5 and is irradiated onto the cornea of the eye to be inspected to form a corneal reflection image. The alignment light reflected by the cornea of the eye to be examined is reflected by the nozzle 5, the glass plate 9,
After passing through the half mirror 10, it is reflected by the half mirror 12, is condensed by the condenser lens 17, passes through the field stop 18, and is received by the photodetector element 19. The alignment state between the eye to be inspected and the non-contact tonometer 1 is detected based on the detection result of the two-dimensional photodetection element 19.

The television camera 14 has an objective lens 11
Also, the anterior ocular segment of the subject's eye is photographed together with the cornea reflection image of the alignment light by the imaging lens 13, and the photographed image is the television monitor
0 is displayed, and the examiner can observe the alignment state. 21 is an LED for detecting the corneal applanation, LE
The light emitted from D21 is collimated by the collimating lens 22. The light reflected by the cornea of the eye to be examined is condensed by the condenser lens 23, passes through the pinhole plate 24, and is received by the photodetector 25. The optical system for detecting the corneal applanation is arranged so that the photodetector 25 detects the maximum light amount when the eye to be inspected is in a predetermined applanation state.

(Processing control system) The signal output from the photo-detecting element 19 is subjected to predetermined processing by the signal detection processing circuit 30 and input to the control circuit 31. The control circuit 31 obtains the alignment state of the subject's eye from the input signal. If this alignment state is within a predetermined allowable range, the control circuit 31 automatically issues a signal for operating the drive circuit 32 (or after the examiner is notified of a message such as alignment completion), The solenoid 3 is driven to start the measurement (by pushing a measurement start switch (not shown)). By driving the solenoid 3, the piston 2 moves with acceleration, and compressed air is blown onto the cornea of the eye to be inspected. The deformed state of the cornea is detected by the photodetector 25, and the output signal of the photodetector 25 is input to the control circuit 31 via the signal detection circuit 33. Reference numeral 34 denotes a pressure detection processing circuit that performs a predetermined process on the output signal of the pressure sensor 6 and inputs the processed signal to the control circuit 31.

FIG. 3 is a diagram showing changes in the air pressure in the compression chamber and changes in the amount of light detected by the photodetector 25 over time during measurement, where a indicates a change in pressure during one cycle. b shows the change in the amount of detected light in one cycle. Signal b from photodetector 25
Indicates a peak, and when it is detected that the eye to be inspected is in an applanation state, the control circuit 31 stops driving the solenoid 3.
The change in the air pressure in the compression chamber shows a peak value after the driving of the solenoid 3 is stopped, and then starts to decrease. The control circuit 31 obtains the pressure value at the timing when the photodetector 25 detects that the eye to be inspected is in the applanation state, and calculates the intraocular pressure based on this pressure value. The intraocular pressure data calculated by the control circuit 31 is displayed on the television monitor 20 via the display circuit 35.

<Fluid Pressure Inspection Device> Next, the construction of the fluid pressure inspection device 40 for inspecting the pressure of the fluid ejected from the non-contact tonometer 1 will be described. Reference numeral 41 is an alignment reflecting plate having a curved surface with a standard radius of curvature of the cornea, and the reflecting plate 41 is attached to the tip of a supporting rod 42 (the reflecting plate 41 is integrally formed with the supporting rod 42). May be formed). The diameters of the reflection plate 41 and the support rod 42 are formed such that they do not block the air flow ejected from the nozzle 5 and do not block the light emitted from the LED 46 described later.
The rear portion of the support rod 42 is held by the support base block 43. The support base block 43 is provided with a fluid receiving portion 44 having an opening centered on the support rod 42, and the opening diameter is designed to receive the entire air flow ejected from the non-contact tonometer 1. The diameter of the nozzle 5 is slightly larger than that of the nozzle 5.

Reference numeral 45 is a pressure sensor, and the pressure sensor 45
Detects the pressure of the fluid sprayed in the fluid receiving portion 44. Reference numeral 46 denotes an LED that emits the same near-infrared light as the LED 21, and the LED 46 is held by the support block 43 and its optical axis is set when the reflector 41 and the non-contact tonometer 1 are placed in a predetermined positional relationship. Are arranged so as to coincide with the detection optical axis of the cornea applanation detection optical system.

The signal detected by the pressure sensor 45 is sent to the amplifier 5
0 through three comparators 51a, 51b and 51
It is input in parallel to c. Variable resistors 52a, 52b and 52c are connected to the other end of each comparator 51, respectively. The resistance value of each variable resistor 52 is preset according to the fluid pressure to be inspected. The inspection pressure is simply adjusted by adjusting the resistance value of each variable resistor 52 based on the air flow ejected by the calibrated non-contact tonometer. To be precise, the fluid pressure (the fluid pressure obtained by calibrating the pressure in the cylinder to the fluid pressure at the position of the cornea) is calibrated to a resistance value corresponding to the pressure on the pressure sensor. The test pressure is, for example, an intraocular pressure value of 10 mmHg, 2
Three types of 0 mmHg and 40 mmHg are set.

Each of the comparators 51 outputs a signal when the voltage level of the signal input from the pressure sensor 45 reaches the voltage level input from the variable resistor 52. 5
Reference numeral 3 is a changeover switch for changing over the connection of the comparator 51 in order to select the inspection pressure. Changeover switch 53
The other end of the pulse generator 5 is connected to the pulse generator 54.
When a signal is input, 4 generates and outputs a signal for one pulse. Reference numeral 55 is a drive circuit for driving the LED 46.

A fluid pressure inspection method using the fluid pressure inspection device 40 having the above configuration will be described. The fluid pressure test device 40 is held by a holder (not shown) on the chin rest of the non-contact tonometer. When the variable resistor 52a is set to the inspection pressure corresponding to the intraocular pressure value of 10 mmHg, the changeover switch 53 is operated to connect it to the comparator 51a.

The alignment of the fluid pressure inspection device 40 is performed in the same manner as the alignment of the eye to be inspected, with the reflection plate 41 being regarded as the cornea of the eye to be inspected. That is, the apex position of the reflection plate 41 corresponds to the apex of the cornea. When the reflector 41 and the non-contact tonometer can be aligned in a predetermined relationship, compressed air is ejected from the nozzle 5 of the non-contact tonometer (or the examiner pushes the measurement start switch to eject the air). ). The injected compressed air raises the pressure of the fluid receiving portion 44, and the pressure sensor 45 detects this. Pressure sensor 4
The signals sequentially detected by 5 are sent to each comparator 51,
The comparator 51a compares the voltage level of the variable resistor 52a with the pulse generator 5 when the voltage level exceeds a preset level.
Send a signal to 4. The pulse generator 54 emits a pulse signal, and the drive circuit 55 is activated by this signal to activate the LED 46.
Lights up. That is, the LED 46 replaces the applanation signal from the LED 21.

When the applanation signal from the LED 46 is obtained,
The device calculates the measured value and displays it on the television monitor 20.
The fluid pressure of the non-contact tonometer 1 can be inspected by comparing and confirming the measured data and the set inspection pressure.

[0023]

As described above, according to the fluid pressure inspection apparatus of the present invention, the fluid pressure ejected from the non-contact tonometer can be easily inspected without making a troublesome adjustment each time of inspection. . In addition, since it has a simple structure with no moving parts, it is very easy to handle, and there is no fear of it changing due to aging or frequency of use.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a non-contact tonometer and a fluid pressure test device.

FIG. 2 is an enlarged view of a main part of FIG.

FIG. 3 is a diagram showing changes in air pressure in the compression chamber and changes in the amount of light detected by a photodetector with time during measurement.

FIG. 4 is a diagram illustrating a configuration of a conventional fluid pressure inspection device.

[Explanation of symbols]

40 Fluid pressure tester 41 Reflector 45 Pressure sensor 46 LED 51 comparator 52 Variable resistor

Claims (3)

(57) [Claims] 1. A fluid pressure of a non-contact tonometer for inspecting the fluid pressure of a non-contact tonometer, which is obtained by ejecting fluid from a nozzle onto a cornea of an eye to be examined and deforming the fluid into a predetermined shape. In the fluid pressure inspection device, an opening slightly larger than the diameter of the nozzle is installed.
Nozzle of the non-contact tonometer, which has a shaved internal space
From the nozzle and the fluid receiving part that receives the fluid to be ejected from
A pressure detecting means for detecting the pressure of fluid in the fluid receiving portion is, selection means for selecting the test pressure, the the detection signal for detecting a fluid pressure corresponding to the test pressure said pressure sensing means is selected by the selection means When the fluid pressure of the non-contact tonometer is measured , the transmission means for transmitting to the non-contact tonometer is provided .
A fluid pressure inspection device, which inspects at the cornea position . 2. A fluid pressure inspecting apparatus for inspecting the fluid pressure of a non-contact tonometer, which obtains the intraocular pressure from the fluid pressure when the fluid is ejected to the cornea of the eye to be inspected and is deformed into a predetermined shape, The pressure detection means for detecting the fluid pressure of the non-contact tonometer, the pressure setting means for setting the pressure to be inspected, and the detection signal when the pressure detection means detects the fluid pressure corresponding to the set pressure A non-contact type tonometer, wherein the non-contact type tonometer is a light emitting unit which emits light toward a light detecting unit which detects a deformation state of the non-contact tonometer. Fluid pressure test device for tonometer. 3. A fluid is jetted to the cornea of an eye to be examined,
Non-contact to obtain intraocular pressure from fluid pressure when deformed to a fixed shape
In a fluid pressure inspection device for inspecting the fluid pressure of a tonometer
Pressure sensor for detecting the fluid pressure of the non-contact tonometer.
The knowing means and the pressure setting means for setting the pressure to be inspected,
The pressure detection means detects the fluid pressure corresponding to the set pressure.
Transmission to send detection signal to the non-contact tonometer when informed
Means for reflecting the alignment light of the non-contact tonometer
Fluid pressure testing device of the non-contact type tonometer which a reflector, characterized in that it comprises the that.