Intraocular pressure measuring device

Abstract

To provide an intraocular pressure measuring device that can reduce the discomfort experienced by examiners during intraocular pressure measurement. [Solution] An intraocular pressure measuring device for measuring the intraocular pressure of an eye under examination, comprising: a fluid discharge means for discharging fluid onto the cornea of ​​the eye under examination via a nozzle; and a temperature changing means for changing the temperature of the fluid discharged from the fluid discharge means. It also comprises a temperature control means for controlling the drive of the temperature changing means. Furthermore, it comprises a fluid transfer means for storing and transferring fluid to the fluid discharge means, which is different from the housing in which the fluid discharge means is housed.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to tonometry for measuring intraocular pressure of an eye to be examined.

BACKGROUND ART

[0002] Tonometry devices are known that measure intraocular pressure by discharging a fluid such as air from a nozzle toward an eye to be examined, and detecting the deformation state (for example, the applanation state) of the cornea caused by the discharged fluid.

PRIOR ART DOCUMENTS

PATENT DOCUMENTS

[0003]

PATENT DOCUMENT 1

SUMMARY OF THE INVENTION

PROBLEMS TO BE SOLVED BY THE INVENTION

[0004] Meanwhile, in the measurement of intraocular pressure of an eye to be examined, many people feel uncomfortable that fluid is discharged toward the eye to be examined, but fluid jet type devices cannot eliminate the discharge. On the other hand, it is conceivable that the temperature of the fluid varies depending on the environment during intraocular pressure measurement, and the temperature of the fluid may increase such discomfort.

[0005] In view of the conventional problems, the present disclosure takes as its technical problem to provide a tonometry device capable of reducing the discomfort of an examinee during intraocular pressure measurement.

MEANS FOR SOLVING THE PROBLEMS

[0006] To solve the above problems, the present disclosure is characterized by having the following configuration.

[0007] A tonometry device for measuring intraocular pressure of an eye to be examined, comprising: a fluid discharging unit that discharges a fluid to the cornea of the eye to be examined via a nozzle; and a temperature changing unit that changes the temperature of the fluid discharged from the fluid discharging unit. [Brief explanation of the drawing]

[0008] [Figure 1] This diagram shows the external configuration of an intraocular pressure measuring device. [Figure 2] This diagram shows the internal configuration of an intraocular pressure measuring device. [Figure 3] This diagram shows the state in which the check valve is blocking the through-hole. [Figure 4] This diagram shows the check valve in a state where it passes through a through-hole. [Figure 5] This is a diagram showing the optical system of an intraocular pressure measuring device. [Figure 6] This flowchart shows the control operation of an intraocular pressure measuring device. [Modes for carrying out the invention]

[0009] <Overview> The outline of the intraocular pressure measuring device according to this embodiment is described below. The items classified in <> below can be used independently or in relation to each other.

[0010] An intraocular pressure measuring device (for example, intraocular pressure measuring device 1) may measure the intraocular pressure of the eye being examined in a non-contact manner. The intraocular pressure measuring device may also include an intraocular pressure measuring means (for example, a measuring unit 100) that measures intraocular pressure by deforming the cornea of ​​the eye being examined with a fluid. For example, the intraocular pressure measuring means may include a fluid discharge means, an intraocular pressure measuring optical system, etc., as part of the intraocular pressure measuring means. Of course, the intraocular pressure measuring device may also include measuring means other than the intraocular pressure measuring means.

[0011] <Fluid discharge means> The intraocular pressure measuring device may include a fluid discharge means (e.g., a fluid discharge unit 200) for discharging a fluid (for example, air, etc.) through a nozzle onto the cornea of ​​the eye being examined. The fluid discharge means may include a first housing (e.g., a housing 215), an airtight chamber (e.g., an airtight chamber 221), and a nozzle (e.g., a nozzle 206). The first housing may house a cylinder and a piston for compressing the fluid. The airtight chamber may house the fluid compressed by the cylinder and piston. The nozzle may be connected to the airtight chamber.

[0012] <Means of changing temperature> The intraocular pressure measuring device may include a temperature changing means (e.g., a temperature changing unit 250) for changing the temperature of the fluid discharged from the fluid discharge means. The temperature changing means may have at least a heat source. For example, the heat source may be a cooling source (such as a cooler), a heating source (such as a heater), a hot and cold source, etc.

[0013] The heat source may be switched on and off by operating a mechanical operating mechanism. For example, it may be switched on and off via the transmission of an electrical signal corresponding to the opening and closing or switching of an electrical circuit when a mechanical switch is pressed. Alternatively, the heat source may be switched on and off by operating an optical operating mechanism. For example, it may be switched on and off via the transmission of a control signal corresponding to the passage or blocking of light when an optical switch is pressed. Of course, the heat source may also be switched on and off by operating an operating mechanism other than mechanical or optical.

[0014] The temperature change means may further include a temperature detection unit. For example, the temperature detection means may be a temperature sensor for detecting the temperature of a fluid. Alternatively, for example, the temperature detection means may be a temperature sensor for detecting the temperature of a reservoir where the fluid is temporarily or permanently stored.

[0015] For example, since the intraocular pressure measurement device has the temperature changing means, it is possible to change the temperature of the fluid ejected toward the subject (the subject's eye) to a temperature that is less likely to cause discomfort. Thereby, the discomfort of the subject during intraocular pressure measurement can be reduced.

[0016] Note that when the heat source is a heating source, it is not always necessary to provide a dedicated component. The heating source may also serve as a member for operating the device. For example, at least one of a light source, a power supply circuit and a control circuit for optical members, a communication circuit, an actuator, a processor, and the like may be used. In this case, it is preferable to provide a temperature detection unit together with the member for operating the device as the heating source, and detect the temperature of the fluid while warming the fluid. Furthermore, a separate cooling source may be provided, and the temperature of the fluid may be detected while cooling the fluid as necessary.

[0017] <Temperature control means> The intraocular pressure measurement device may include a temperature control means (for example, the control unit 80) that controls driving of the temperature changing means. The temperature control means may control on / off of the heat source based on a control signal accompanying an operation of an optical operation means, or a control signal accompanying an operation of an operation means different from a mechanical and optical operation means. Further, the temperature control means may control the heat source in accordance with the temperature detected by the temperature detection unit to raise or lower the temperature of the fluid. Alternatively, the temperature of the fluid may be kept constant. Since the intraocular pressure measurement device has the temperature control means together with the temperature changing means, the temperature of the fluid can be maintained at a temperature that is less likely to cause discomfort.

[0018] The temperature control means may maintain the temperature of the fluid at any temperature that can be changed by the examiner. Further, the temperature control means may maintain the temperature of the fluid at a predetermined temperature set in advance based on experiments, simulations, or the like. For example, the temperature of such a fluid may be a temperature that is generally considered less likely to cause discomfort. As an example, it may be 20°C to 35°C.

[0019] In the present embodiment, the temperature changing unit may be arranged in the fluid discharging unit. For example, the temperature changing unit may be arranged inside the fluid discharging unit. As an example, the inside of the fluid discharging unit may be an inner wall surface of the fluid discharging unit. Also, for example, the temperature changing unit may be arranged outside the fluid discharging unit. As an example, the outside of the fluid discharging unit may be an outer wall surface in contact with the fluid discharging unit. Alternatively, as an example, the outside of the fluid discharging unit may be the periphery that does not come into contact with the fluid discharging unit. In this case, in consideration of the change in density accompanying the change in the temperature of the fluid, the temperature changing unit may be arranged at the upper part or the lower part of the fluid discharging unit.

[0020] In the present embodiment, the temperature changing unit may be arranged in the later-described fluid transfer unit. For example, the temperature changing unit may be arranged inside or outside the fluid transfer unit. As an example, the temperature changing unit may be arranged on the inner wall surface or the outer wall surface of the fluid transfer unit, or around the fluid transfer unit. For example, when the temperature changing unit is provided in the fluid transfer unit, a fluid is stored separately from the fluid to be discharged, and the temperature of the stored fluid can be adjusted. Thereby, in the intraocular pressure measurement of the subject's eye, the temperature-adjusted fluid can be efficiently discharged.

[0021] <Fluid transfer unit> The intraocular pressure measurement apparatus may include a fluid transfer unit that stores a fluid and transfers the fluid to the fluid discharging unit, the fluid transfer unit being different from the housing in which the fluid discharging unit is accommodated (for example, the fluid transfer section 230). The fluid transfer unit may be connected to the fluid discharging unit. The fluid transfer unit may have at least a storage section (for example, a storage chamber 236). The storage section may be a space for storing (accommodating) the fluid. For example, in this case, the fluid may naturally flow to the fluid discharging unit depending on the density of the fluid. Note that the fluid transfer unit may have a blower section (for example, a fan or the like), and may be configured such that the fluid flows to the fluid discharging unit by the blower section.

[0022] The fluid transfer means may further include a second housing (e.g., housing 237). The second housing may house a cylinder and a piston for compressing the fluid. For example, in this case, the fluid compressed by the cylinder and piston of the second housing is pushed out to the fluid discharge means.

[0023] In this embodiment, one fluid transfer means may be provided. The one fluid transfer means may store the fluid required for one intraocular pressure measurement of the cornea, or it may store the fluid required for multiple intraocular pressure measurements of the cornea. In this embodiment, multiple fluid transfer means may be provided. The multiple fluid transfer means may each store the fluid required for one intraocular pressure measurement of the cornea, thereby storing the fluid required for multiple intraocular pressure measurements of the cornea. Alternatively, the multiple fluid transfer means may each store the fluid required for multiple intraocular pressure measurements of the cornea, thereby storing the fluid required for multiple intraocular pressure measurements of the cornea.

[0024] <Transport control means> The intraocular pressure measuring device may include a transport control means (e.g., a control unit 80) that controls the driving of the fluid transport means. The transport control means may push the fluid stored in the fluid transport means to the fluid discharge means. For example, the transport control means may at least control the piston of the second storage section, thereby causing the compressed fluid in the storage section to be discharged to the fluid discharge means. This allows for the efficient transport of fluid at an appropriate temperature into the fluid discharge means.

[0025] The transport control means may push out one dose of fluid from the fluid transport means each time the intraocular pressure of the cornea is measured. For example, if multiple doses of fluid are stored in one fluid transport means, the transport control means may push out one dose of fluid at a time. Alternatively, if multiple doses of fluid are stored separately in multiple fluid transport means, the transport control means may push out one dose of fluid at a time. This allows for the continuous use of temperature-controlled fluid even when measuring the intraocular pressure of the eye being examined, thereby improving the efficiency and reducing the time required for intraocular pressure measurement.

[0026] In this embodiment, the temperature control means and the transfer control means may be provided as separate control means. Of course, the temperature control means and the transfer control means may also be provided as a single control means and used interchangeably.

[0027] <Check valve> The intraocular pressure measuring device may be equipped with a check valve (e.g., check valve 240) to suppress backflow of fluid when fluid is not being transported by the fluid transport means. The check valve may be provided in the flow path of the connecting section that connects the fluid transport means and the fluid discharge means. For example, the check valve may be located at the outlet of the fluid transport means and at the inlet of the connecting section. Alternatively, for example, the check valve may be located at any position between the inlet and outlet of the connecting section. Alternatively, for example, the check valve may be located at the outlet of the connecting section and at the inlet of the fluid discharge means.

[0028] The check valve may be opened and closed via a drive source. Alternatively, the check valve may be opened and closed using the pressure difference between the inside and outside of the fluid transfer means. For example, it may be opened and closed by controlling the positive and negative pressure inside and outside the fluid transfer means. This can suppress the possibility of the fluid temperature decreasing or increasing due to mixing of, for example, a fluid whose temperature has not been adjusted in the fluid discharge means with a fluid whose temperature has been adjusted in the fluid transfer means (for example, a fluid kept at a constant temperature) in the fluid transfer means. Alternatively, it can suppress the possibility of the fluid temperature decreasing or increasing due to mixing of a temperature-adjusted fluid transferred into the fluid discharge means with a fluid whose temperature will be adjusted in the fluid transfer means. Therefore, it becomes possible to discharge fluid at a more stable temperature for the eye being examined.

[0029] <Examples> The intraocular pressure measuring device of this embodiment will be described below with reference to the drawings. For example, the intraocular pressure measuring device discharges fluid onto the cornea of ​​the eye being examined and measures the intraocular pressure of the eye being examined based on the relationship between the deformation state of the cornea at that time and the pressure of the fluid.

[0030] Figure 1 shows the external configuration of the intraocular pressure measuring device 1. The intraocular pressure measuring device 1 may include a base 2, a face support unit 3, a drive unit 4, a control unit 80, a display unit 85, a measurement unit (examination unit) 100, etc. The base 2 supports the measurement unit 100 so that it can move. The face support unit 3 supports the face of the person being examined. The face support unit 3 includes a forehead rest 3a, a chin rest 3b, a chin rest sensor 3c, a chin rest drive unit 3d, etc. The chin rest sensor 3c detects whether the chin is resting on the chin rest 3b. The chin rest drive unit 3d moves the chin rest 3b up and down to adjust its height. The drive unit 4 moves the measurement unit 100 relative to the base 2 in the XYZ direction (three-dimensional direction). Of course, the drive unit 4 may be provided separately for each direction of movement. The drive unit 4 may be equipped with a well-known movement mechanism. The control unit 80 controls the entire intraocular pressure measuring device 1. The display unit 85 displays, for example, an observation image of the eye under examination and measurement results. The display unit 85 may be provided integrally with the intraocular pressure measuring device 1, or it may be provided separately from the device. The display unit 85 may be positioned so that the display screen faces not only the subject but also the subject. Various operation instructions from the examiner or the subject are input to the display unit 85. The display unit 85 may also be used as an operation unit 86. In this case, the display unit 85 is used for various settings of the intraocular pressure measuring device 1, measurement start, operation during fluid inhalation, etc. Various human interfaces such as a joystick, mouse, keyboard, trackball, buttons may be used as the operation unit 86. The measurement unit 100 includes an optical system for measuring the eye under examination. In this embodiment, the measurement unit 100 includes a fluid discharge unit 200, a fluid transfer unit 230, a temperature change unit 250, a check valve 240, a measurement optical system 10, etc.

[0031] <Fluid discharge section> Figure 2 shows the internal configuration of the intraocular pressure measuring device 1. The fluid discharge unit 200 discharges fluid onto the cornea of ​​the eye E being examined. For example, the fluid discharge unit 200 includes a first cylinder 201, a first piston 202, a first solenoid actuator (hereinafter referred to as the first solenoid) 203, a nozzle 206, a glass plate 208, a glass plate 209, a pressure sensor 212, an air vent hole 213, an airtight chamber 221, and a housing section 223.

[0032] The housing section 215 houses at least a first cylinder 201 and a first piston 202 for compressing a fluid, such as air, to be discharged to the eye under examination. The first cylinder 201 and the first piston 202 are used as a fluid compression mechanism for compressing the fluid. For example, the first cylinder 201 is cylindrical. The first piston 202 slides along the axial direction of the first cylinder 201. The first piston 202 compresses the fluid in the compression chamber 224 within the first cylinder 201.

[0033] The first solenoid 203 is a so-called linear solenoid and operates linearly. The first solenoid 203 comprises a movable body 204 and a coil 205. For example, a magnetic material such as a permanent magnet is used for the movable body 204. When current flows through the coil 205, a magnetic field is generated inside the coil 205. The movable body 204 is moved in direction A in Figure 2 by the electromagnetic force it receives from the magnetic field. The movable body 204 is fixed to the first piston 202 by screws, bolts, nuts, etc. (not shown). Therefore, the first piston 202 moves together with the movable body 204. The movement of the movable body 204 causes the first piston 202 to move in the compression direction (direction A in Figure 2, which is the forward direction).

[0034] The direction of movement of the movable body 204 can be changed by changing the direction of the current flowing through the coil 205. For example, by flowing a forward current through the coil 205 to move the first piston 202 in direction A and compress the fluid in the compression chamber 224, and then flowing a reverse current through the coil 205, the first piston 202 can be moved in direction B (reverse direction) and returned to its initial position. Note that the first solenoid 203 is not limited to a linear solenoid; it may be a rotary solenoid or another drive source.

[0035] Nozzle 260 is connected to the airtight chamber 221. Nozzle 206 discharges the fluid compressed in the compression chamber 224 to the outside. Nozzle 206 has a discharge port 206a. Glass plate 208 is transparent and holds the nozzle 206 while transmitting observation light and alignment light. Glass plate 209 forms the rear wall of the airtight chamber 221 while transmitting observation light and alignment light. Pressure sensor 212 detects the pressure in the airtight chamber 221. Air vent hole 213 reduces the resistance until the first piston 202 gains initial velocity and can provide a pressure change that rises in proportion to time.

[0036] <Fluid transfer section> The fluid transfer unit 230 stores the fluid and transfers the fluid to the fluid discharge means. For example, the fluid transfer unit 230 includes a second cylinder 231, a second piston 232, a second solenoid 233, a storage chamber 236, a housing section 237, a through hole 239, and the like.

[0037] The housing 237 houses at least a second cylinder 231 and a second piston 232 for compressing the fluid to be transferred to the fluid discharge means. The second cylinder 231 and the second piston 232 are used as a fluid compression mechanism for compressing the fluid. For example, the second cylinder 231 is cylindrical. For example, the second cylinder 231 has a through hole 239 for taking in fluid from outside the second cylinder 231. For example, the second piston 232 slides along the axial direction of the second cylinder 231. The second piston 232 compresses the fluid in the storage chamber 236 within the second cylinder 231. The second solenoid 233, like the first solenoid 203, comprises a movable body 234 and a coil 235. For example, the second piston 232 and the movable body 204 fixed to the second piston 232 are moved in the compression direction or the retraction direction by controlling the direction of the current flowing through the coil 205.

[0038] The fluid transfer unit 230's storage chamber 236 can store the fluid necessary for multiple intraocular pressure measurements of the cornea. For example, with each intraocular pressure measurement, the second piston 232 moves stepwise from its initial position in the compression direction, narrowing the space in the storage chamber 236. Then, one dose of fluid is pushed out at a time. Also, for example, once all the fluid necessary for multiple intraocular pressure measurements has been used, the second piston 232 moves all at once back to its initial position, widening the space in the storage chamber 236. At this time, fluid is drawn in from outside the fluid transfer unit 230 through the through-hole 239 (details will be described later), and the fluid necessary for multiple intraocular pressure measurements is stored again.

[0039] <Temperature change section> The temperature change unit 250 changes the temperature of the fluid discharged from the fluid discharge means. For example, the temperature change unit 250 is provided inside the fluid transfer unit 230 and changes the temperature of the fluid stored in the fluid transfer unit 230. For example, the temperature change unit 250 includes at least a heat source 251. The heat source 251 is a heater (hereinafter referred to as heater 251). Furthermore, for example, the temperature change unit 250 includes a detection unit 252. The detection unit 252 is a thermometer (hereinafter referred to as thermometer 252). For example, the thermometer 252 measures the temperature of the storage chamber 236.

[0040] <Connection part> The connecting section 260 connects the fluid discharge section 200 and the fluid transfer section 230. The connecting section 260 is the fluid pathway through which the fluid from the fluid transfer section 230 is transferred to the fluid discharge section 200. <Check valve>

[0041] In this embodiment, a check valve 240 is provided in the fluid flow path F1, which is the fluid flow path F1 through the fluid transfer section 230, the connecting section 260, and the fluid discharge section 200 to the nozzle 206. The check valve 240 has a first check valve 240a, a second check valve 240b, and a third check valve 240c.

[0042] A first check valve 240a and a second check valve 240b are provided in the fluid discharge section 200. The first check valve 240a is provided between the compression chamber 224 and the nozzle 260. The second check valve 240b is provided between the compression chamber 224 and the connecting section 260. For example, the second check valve 240b is provided on the compression chamber 224 side and closes the opening of the connecting section 260. A third check valve 240c is provided in the fluid transfer section 230. The third check valve 240c is provided between the storage chamber 236 and the through hole 239. For example, the third check valve 240c is provided on the compression chamber 224 side and closes the opening of the through hole 239.

[0043] The third check valve 240c will be explained using Figures 3 and 4. Figure 3 shows the third check valve 240c in a state where it is blocking the through-hole 239. Figure 3(a) is a view of the third check valve 240c from the opposite direction to the flow path F1, and Figure 3(b) is a cross-sectional view of the CC of the third check valve 240c. Figure 4 shows the third check valve 240c in a state where it is passing through the through-hole 239. The third check valve 240c includes a check valve seat 310, a check valve body 311, a fastening part 312, an outlet 313, etc. Note that the first check valve 240a and the second check valve 240b have the same structure as the third check valve 240c and are therefore omitted.

[0044] The third check valve 240c has a structure in which a check valve body 311 is assembled to a check valve seat 310 by a fastening part 312. The check valve body 311 is a soft film-like (or sheet-like) material such as a resin film or rubber sheet. The outlet 313 of the check valve seat 310 is positioned to align with the opening of the through hole 239. When fluid is discharged, the fluid flows in the direction of the flow path F1, deforming the check valve body 311 and passing through the third check valve 240c (see Figures 3(b) and 4). On the other hand, when fluid is drawn in, the fluid flows in the opposite direction to the flow path F1 and hits the check valve body 311, but since the check valve body 311 is seated on the check valve seat 310 and does not deform, it cannot flow into the outlet 313. As a result, the third check valve 240c can allow the fluid to pass only in the direction of the flow path F1. <Measurement optical system> Figure 5 is a schematic diagram of the measurement optical system 10 of the intraocular pressure measuring device 1. For example, the measurement optical system 10 includes an observation optical system 130, an index projection optical system 140, a fixation optical system 48, a corneal deformation detection optical system 500, a corneal thickness measurement optical system 70, a face imaging optical system 90, and so on.

[0045] <Observation Optical System> The observation optical system 130 captures an anterior segment image for observing the eye under examination. The anterior segment image captured by the observation optical system 130 is used for alignment of the measurement unit 100, etc. For example, the observation optical system 130 includes a beam splitter 31, an objective lens 32, a dichroic mirror 33, an imaging lens 37, a filter 34, an image sensor 35, and the like. Illumination light from the infrared illumination light source 30 is reflected by the anterior segment and formed on the image sensor 35 via the beam splitter 31, objective lens 32, dichroic mirror 33, imaging lens 37, and filter 34. Optical axis L1 is used as the observation optical axis.

[0046] The filter 34 transmits light from the infrared illumination source 30 and the alignment indicator light source 40, but is opaque to light from the infrared light source 50 for corneal deformation detection (described later) and to visible light. The image formed on the image sensor 35 is displayed on the display unit 85.

[0047] <Indicator projection optical system> The indicator projection optical system 140 projects an indicator onto the eye under examination. The indicator projection optical system 140 includes an indicator light source 40, a projection lens 41, and the like. For example, the indicator light source 40 can be switched on / off. The indicator light source 40 may also have an adjustable light intensity. Infrared light projected from the indicator light source 40 via the projection lens 41 is reflected by the beam splitter 31 and projected onto the eye under examination from the front. The corneal bright spot formed at the corneal apex by the indicator light source 40 is imaged onto the image sensor 35 via the beam splitter 31 and filter 34 and used for detecting alignment in the up, down, left, and right directions. The optical axis L1 is used as the alignment optical axis.

[0048] The fixation optical system 48 has an optical axis L1 and presents the fixation target to the eye E being examined from the front. In this case, the optical axis L1 is used as the fixation optical axis. For example, the fixation optical system 48 has a visible light source (fixation lamp) 45, a projection lens 46, and a dichroic mirror 33, and projects light onto the eye E being examined to cause it to fixate in the front direction. The visible light source 45 can be an LED, a laser, or other light source. In addition, the visible light source 45 can be a pattern light source such as a point light source, a slit light source, or a ring light source, or a two-dimensional display such as a liquid crystal display.

[0049] The visible light emitted from the visible light source 45 passes through the projection lens 46, is reflected by the dichroic mirror 33, passes through the objective lens 32, and is projected onto the fundus of the eye under examination E. As a result, the eye under examination E fixates on a fixed point in the forward direction, fixing the line of sight. The visible light emitted from the visible light source 45 is converted into a parallel beam of light by passing through the projection lens 46 and the objective lens 32.

[0050] The corneal deformation detection optical system 500 includes a light-emitting optical system 500a and a light-receiving optical system 500b, and is used to detect the deformation state of the cornea Ec. Each optical system 500a and 500b is located in the measuring unit 100 and is moved three-dimensionally by the drive unit 4.

[0051] The light projection optical system 500a has an optical axis L3 as the light projection optical axis and illuminates the cornea Ec of the eye under examination E from an oblique direction. The light projection optical system 500a includes, for example, an infrared light source 50, a collimator lens 51, and a beam splitter 52. The light receiving optical system 500b has a photodetector 57 and receives the reflected light of the illumination light at the cornea Ec of the eye under examination E. The light receiving optical system 500b is arranged substantially symmetrically with respect to the light projection optical system 500a with respect to the optical axis L1. The light receiving optical system 500b includes, for example, a lens 53, a beam splitter 55, a pinhole plate 56, and a photodetector 57, and forms an optical axis L2 as the light receiving optical axis.

[0052] Light emitted from the infrared light source 50 is made into a nearly parallel beam by the collimator lens 51, reflected by the beam splitter 52, and then becomes coaxial (coincident) with the optical axis L3 of the light receiving optical system 70b (described later), and is projected onto the cornea Ec of the eye under examination. The light reflected from the cornea Ec becomes coaxial (coincident) with the optical axis L2 of the light projection optical system 70a (described later), passes through the lens 53, is reflected by the beam splitter 55, passes through the pinhole plate 56, and is received by the photodetector 57. The lens 53 is coated with a coating that is opaque to the light from the infrared illumination light source 30 and the indicator light source 40. Furthermore, the optical system for detecting corneal deformation is arranged so that the amount of light received by the photodetector 57 is maximized when the eye under examination is in a predetermined deformed state (flattened state).

[0053] Furthermore, the corneal deformation detection optical system 500 also serves as part of the first working distance detection optical system, and the light projection optical system of the first working distance detection optical system also serves as the light projection optical system 500a of the corneal deformation detection optical system 500. The light receiving optical system 600b, which receives reflected light from the cornea Ec by the infrared light source 50, has, for example, the lens 53, beam splitter 58, focusing lens 59, and position detection element 60 of the light projection optical system 500a, and forms the optical axis L2 as the light receiving optical axis.

[0054] Illumination light emitted from the infrared light source 50 and reflected by the cornea Ec forms a virtual image of the infrared light source 50, which is a reference image. The light from this reference image passes through lens 53 and beam splitter 55, is reflected by beam splitter 58, passes through focusing lens 59, and enters a one-dimensional or two-dimensional position detection element 60 such as a PSD or line sensor. As the eye under examination E (cornea Ec) moves in the working distance direction (Z direction), the reference image from the infrared light source 50 also moves on the position detection element 60, so the control circuit 20 obtains working distance information based on the output signal from the position detection element 60. In this embodiment, the output signal from the position detection element 60 is used for alignment (rough adjustment) in the working distance direction (Z direction). The light receiving optical system 600b of the first working distance detection optical system does not have as high a magnification as the light receiving optical system 70b described later. Therefore, the distance detection range in the Z direction of the position detection element 60 is wider than that of the light receiving element 77.

[0055] The corneal thickness measurement optical system 70 includes a light-emitting optical system 70a, a light-receiving optical system 70b, and a fixation optical system 48, and is used to measure the corneal thickness of the eye E under examination. In addition, the light-emitting optical system 70a also serves as part of the corneal deformation detection optical system 500 and the first working distance detection optical system.

[0056] The light projection optical system 70a has an optical axis L2 as the light projection optical axis and irradiates illumination light (measurement light) from an oblique direction toward the cornea Ec of the eye E under examination. The light projection optical system 70a includes, for example, an illumination light source 71, a focusing lens 72, a light limiting member 73, a concave lens 74, and a lens 53 which is also used in the corneal deformation detection optical system 500. The illumination light source 71 is a visible light source or an infrared light source (including near-infrared), and for example, a light source such as an LED or a laser is used. The focusing lens 72 focuses the light emitted from the illumination light source 71. The infrared light source 50 and the illumination light source 71 use different wavelength bands.

[0057] The light limiting member 73 is positioned in the optical path of the light projection optical system 70a and limits the light emitted from the illumination light source 71. The light limiting member 73 is positioned approximately conjugate to the cornea Ec. For example, a pinhole plate or a slit plate can be used as the light limiting member 73. The light limiting member 73 is used as an aperture that allows some of the light emitted from the illumination light source 71 to pass through while blocking other light. The light projection optical system 70a then forms a predetermined pattern of light beam (e.g., a spot beam, a slit beam) on the cornea of ​​the eye E under examination.

[0058] The light-receiving optical system 70b has a light-receiving element 77 and receives reflected light from the illuminating light on the front and back surfaces of the cornea of ​​the eye under examination E. The light-receiving optical system 70b is arranged approximately symmetrically with respect to the light-emitting optical system 70a with respect to the optical axis L1. The light-receiving optical system 70b has, for example, a light-receiving lens 75, a concave lens 76, and a light-receiving element 77, and forms the optical axis L3 as the light-receiving optical axis. Note that the light-receiving optical system 70b in Figure 5 also serves as a second working distance detection optical system for detecting the alignment state in the Z direction with respect to the eye under examination E.

[0059] The light-receiving element 77 has multiple photoelectric conversion elements and receives reflected light from the front and back surfaces of the cornea, respectively. For example, the light-receiving element 77 can be a light detection device such as a one-dimensional line sensor or a two-dimensional area sensor. The light-receiving optical system 70b of the corneal thickness measurement optical system 70 and the second working distance detection optical system is used for observation at a high magnification. Therefore, the distance detection range of the light-receiving element 77 in the Z direction is narrower than that of the position detection element 60.

[0060] As the eye under examination E (cornea Ec) moves in the working distance direction (Z direction), the reflected light from the illumination light source 71 at the cornea Ec also moves across the photodetector 77. Therefore, the control unit 80 obtains working distance information based on the output signal from the photodetector 77 of the second working distance detection optical system. The control unit 80 also uses this output signal from the photodetector 77 to determine the corneal deformation state and blinking of the eye under examination E, and controls the drive of the first solenoid 203.

[0061] Light emitted from the illumination light source 71 is focused by the focusing lens 72, illuminating the light limiting member 73 from behind. After the light from the illumination light source 71 is limited by the light limiting member 73, it is imaged (focused) near the corneal Ec by the lens 53. Near the corneal Ec, for example, a pinhole image (when a pinhole plate is used) or a slit image (when a slit plate is used) is formed. At this time, the light from the illumination light source 71 is imaged near the point where it intersects with the visual axis on the corneal Ec.

[0062] When illumination light is projected onto the cornea Ec by the light projection optical system 70a, the reflected light from the cornea Ec travels in a direction symmetric to the projected light beam with respect to the optical axis L1. The reflected light is then imaged by the light-receiving lens 75 onto the light-receiving surface on the light-receiving element 77.

[0063] The lens 53, which is used in both the light-receiving optical systems 500b and 600b and the light-emitting optical system 70a, is positioned to concentrate the reflected light from the infrared light source 50 at the center of the hole in the pinhole plate 56, and to concentrate the illumination light from the illumination light source 71 at both the front and back surfaces of the corneal Ec.

[0064] The face imaging optical system 90, for example, captures the face of a subject. The face imaging optical system 90 is, for example, an optical system for capturing a face that includes at least one of the subject's left or right eyes. For example, as shown in Figure 3, the face imaging optical system 90 of this embodiment mainly comprises, for example, an image sensor 91 and an imaging lens 92.

[0065] The face imaging optical system 90 is positioned to capture both eyes of the subject when the measuring unit 100 is in its initial position. In this embodiment, the initial position of the measuring unit 100 is set to a position shifted to the right with respect to the optical axis L1 of the measuring unit 100 to facilitate examination of the right eye. Therefore, the face imaging optical system 90 is positioned to capture both eyes of the subject when the measuring unit 100 is in its initial position shifted to the right. For example, the face imaging optical system 90 is positioned at the center of the machine when the measuring unit 100 is in its initial position. For example, if the initial position is set based on half the interpupillary distance, i.e., the interpupillary distance of one eye, the face imaging optical system 90 may be positioned shifted to the left or right by the interpupillary distance of one eye with respect to the center of the machine of the device body.

[0066] In this embodiment, the face imaging optical system 90 is moved together with the measurement unit 100 by the drive unit 4. Of course, the face imaging optical system 90 may also be fixed to the base 2 and not move.

[0067] The face imaging optical system 90 may also be a wide-angle camera. In this case, the imaging lens 92 may be, for example, a wide-angle lens. For example, wide-angle lenses include fisheye lenses and conical lenses. This allows the face imaging optical system 90 to reliably capture the subject's face with a wide field of view. The face imaging optical system 90 may also perform infrared imaging. This makes the captured image less susceptible to the influence of the surrounding environment. Of course, it may also be a camera that captures visible light.

[0068] <Control System> The intraocular pressure measuring device 1 includes a control unit 80 (see Figure 2). The control unit 80 is responsible for various controls of the intraocular pressure measuring device 1. For example, the control unit 80 includes a general CPU (Central Processing Unit) 81, ROM 82, RAM 83, etc. For example, the ROM 82 stores the intraocular pressure measuring device control program, initial values, etc. for controlling the intraocular pressure measuring device 1. For example, the RAM 83 temporarily stores various information. The control unit 80 is connected to the measurement unit 100, the face imaging optical system 90, the drive unit 4, the display unit 85, the operation unit 86, the chin rest drive unit 3d, the storage unit (e.g., non-volatile memory) 84, etc. For example, the storage unit 84 is a non-transient storage medium that can retain its contents even if the power supply is cut off. For example, a hard disk drive, a removable USB flash memory, etc. can be used as the storage unit 84.

[0069] <Control operation> The control operation of the intraocular pressure measuring device 1, which has the above configuration, will be explained with reference to Figure 6. Here, we will give an example of measuring intraocular pressure using the intraocular pressure measuring device 1, but this is just one example, and it is also possible to measure other things such as corneal pressure.

[0070] (Step S101: Various settings) The examiner selects an intraocular pressure measurement mode by operating the display unit 85 or the operation unit 86. The control unit 80 drives the heater 251 of the temperature change unit 250 in response to the operation signal based on the selection of the intraocular pressure measurement mode, warming the air pre-stored in the storage chamber 236 of the fluid transfer unit 230. The control unit 80 also displays the temperature detected by the thermometer 252 of the temperature change unit 250 on the display unit 85. For example, the control unit 80 may change the display color of the numerical value according to the air temperature. For example, the control unit 80 may display the numerical value in white when the air temperature is below a predetermined temperature, and in orange when the air temperature is above the predetermined temperature.

[0071] In this embodiment, when the intraocular pressure measurement mode is selected, the output of the heater 251 is increased or decreased to maintain the air at approximately 35 degrees Celsius, close to body temperature. Of course, a temperature other than 35 degrees Celsius may be set, or the examiner may be able to set any temperature from a settings screen or the like.

[0072] (Step S102: Air transfer) Next, the examiner prepares to use warmed air for measuring the intraocular pressure of the eye under examination. For example, when the device is started, the air present in the compression chamber 224 of the fluid discharge unit 200 may be at a temperature that the subject may find uncomfortable. However, the air whose temperature has been adjusted in step S1 is normally prevented from flowing into the fluid discharge unit 200 by the second check valve 240b. Therefore, it is necessary to expel the cold air from the fluid discharge unit 200 and transfer the warm air from the fluid transfer unit 230 to the fluid discharge unit 200.

[0073] The inspector may confirm that the air temperature in the fluid transfer unit 230 has reached 35 degrees Celsius by the numerical indicator color and operate an air transfer button (not shown). Based on the operation signal from the air transfer button, the control unit 80 drives the first solenoid 203 to move the first piston 202 in the compression direction. Alternatively, when the control unit 80 detects that the air temperature in the fluid transfer unit 230 has reached 35 degrees Celsius, it may automatically drive the first solenoid 203 to move the first piston 202 in the compression direction. As a result, the air is compressed in the compression chamber 224, passes through the first check valve 240a, and is discharged from the nozzle 206.

[0074] When the discharge of compressed air from the nozzle 206 is complete, the control unit 80 moves the first piston 202 in the retraction direction, returning it to its initial position. At the same time as returning the first piston 202 to its initial position, the control unit 80 drives the second solenoid 233, moving the second piston 232 one step in the compression direction. At this time, the air balance between the fluid discharge section 200 and the fluid transfer section 230 is disrupted, and the compression chamber 224 becomes negative pressure, while the storage chamber 236 becomes positive pressure. Since air flows from negative pressure to positive pressure, air attempts to flow into the compression chamber 224 from the nozzle 260 and the storage chamber 236 via the first check valves 240a and 240b, respectively. However, the air attempting to flow from the nozzle 260 into the compression chamber 224 cannot flow into the compression chamber 224 because the check valve body of the first check valve 240a is seated on the check valve seat. On the other hand, air attempting to flow from the storage chamber 236 to the compression chamber 224 can enter the compression chamber 224 because the check valve body of the second check valve 240b moves away from the check valve seat. In other words, air flows into the compression chamber 224 only from the fluid transfer section 230 in the direction of the flow path F1. As a result, the fluid discharge section 200 is filled with warm air, making it possible to use warm air for intraocular pressure measurement.

[0075] (Step S103: Alignment) The examiner places the subject's face on the face support unit 3. Based on the detection signal from the chin rest sensor 3c, the control unit 80 detects that the chin is resting on the chin rest 3b, illuminates the subject's face, and captures an image of the anterior segment of the subject's eye. The control unit 80 also displays the anterior segment image on the display unit 85.

[0076] The examiner operates the control unit 86 to move the measuring unit 100 relative to the eye under examination in at least one of the X, Y, and Z directions, while confirming the anterior segment image of the eye under examination. For example, the measuring unit 100 is moved in the XY direction so that the center position of the alignment index image included in the anterior segment image matches the optical axis L1. Alternatively, the measuring unit 100 is moved in the Z direction based on the image ratio between the image spacing of the alignment index image at infinity and the image spacing of the alignment index image at finite distance. The movement of the measuring unit 100 relative to the eye under examination can also be performed fully automatically. Alignment is completed when the control unit 80 detects that the displacement of the optical axis L relative to the center position of the alignment index image and the displacement of the image ratio of the alignment index image are within an acceptable range.

[0077] (Step S104: Measurement) Once the alignment between the eye under examination and the measurement unit 100 is complete, the control unit 80 measures the intraocular pressure using the fluid discharge unit 200 and the corneal deformation detection optical system 500. For example, the control unit 80 drives the first solenoid 203 to move the first piston 202 in the compression direction. This compresses the air in the first cylinder 201. The air used here is heated to 35 degrees Celsius. Alternatively, for example, the control unit 80 blows compressed air from the nozzle 206 towards the cornea. The cornea is gradually deformed by the blowing of compressed air, and when it reaches a flattened (or compressed) state, the maximum amount of light is incident on the photodetector 57. The control unit 80 determines the intraocular pressure value based on the output signal from the pressure sensor 212 and the output signal from the photodetector 57.

[0078] When measuring intraocular pressure continuously, such as by blowing compressed air onto the eye being examined (measured eye) multiple times or switching between the right and left eyes, the second piston 232 in the fluid transfer unit 230 moves in the compression direction one step at a time, supplying and consuming one dose of air to the fluid discharge unit 200.

[0079] As described above in step S102, once the compressed air blowing is complete, the control unit 80 returns the first piston 202 to its initial position and simultaneously moves the second piston 232 one step. Due to the air balance between the fluid discharge unit 200 and the fluid transfer unit 230 (for example, the relationship between negative and positive pressure), one batch of heated air is transferred to the fluid discharge unit 200. For example, the second piston 232 can move in 10 steps, and one batch of heated air is transferred sequentially, for a total of 10 batches, by being pushed out. The amount of air that can be stored in the storage chamber 236 and the number of steps to which the air can be moved are not limited.

[0080] When the air stored in the storage chamber 236 is depleted (i.e., when the second piston 232 has moved to the 10th stage), the control unit 80 returns the second piston 232 to its initial position. At this time, the air balance between the outside and inside of the fluid transfer unit 230 is disrupted, resulting in a positive pressure state outside the fluid transfer unit 230 and a negative pressure state inside the storage chamber 236. Since air flows from negative pressure to positive pressure, air attempts to flow into the storage chamber 236 from the compression chamber 224 and the outside of the fluid transfer unit 230 via the second check valves 240b and 240c, respectively. However, the air attempting to flow from the compression chamber 224 into the storage chamber 236 cannot enter because the check valve body of the second check valve 240b is seated on the check valve seat. On the other hand, air attempting to flow from outside the fluid transfer section 230 into the storage chamber 236 can enter the storage chamber 236 because the check valve body 311 of the third check valve 240c separates from the check valve seat 310. In other words, air flows into the storage chamber 236 only from outside the fluid transfer section 230 in the direction of the flow path F1. As a result, the storage chamber 236 is filled with outside air (cold air). In the storage chamber 236, the cold air is heated to 35 degrees by the heater 251.

[0081] Furthermore, the timing at which the first piston 202 is returned to its initial position and the timing at which the second piston 232 is returned to its initial position are different, as determined by the control unit 80. For example, the control unit 80 may move the second piston 232 of the fluid transfer unit 230 to its initial position at a timing before air is present in the compression chamber 224 of the fluid discharge unit 200 and before the first piston 202 is moved in the compression direction. Alternatively, the control unit 80 may move the second piston 232 of the fluid transfer unit 230 to its initial position at a timing after the air has been pushed out of the compression chamber 224 and the first piston 201 has been moved backward to its initial position. In these cases, the compression chamber 224 is under positive pressure, the storage chamber 236 is under negative pressure, and the outside of the fluid transfer unit 230 is under negative pressure. Air flowing from the compression chamber 224 towards the storage chamber 236 is blocked by the second check valve 240b, but air flowing from the outside towards the storage chamber 236 is not blocked by the third check valve 240c.

[0082] (Step S105: Output Result) When the control unit 80 acquires the measurement results for the right and left eyes, it outputs this data. For example, the control unit 80 displays the measurement results on the display unit 85, prints them out, or outputs them to an external device wirelessly or via a wired connection.

[0083] As described above, the intraocular pressure measuring device of this embodiment is an intraocular pressure measuring device for measuring the intraocular pressure of an eye under examination, and comprises a fluid discharge means for discharging fluid onto the cornea of ​​the eye under examination via a nozzle, a temperature changing means for changing the temperature of the fluid discharged from the fluid discharge means, and a discharge control means for controlling the drive of the fluid discharge means. For example, by having a temperature changing means in the intraocular pressure measuring device, the temperature of the fluid discharged towards the subject (eye under examination) can be changed to a temperature that is less likely to cause discomfort. This can reduce the discomfort experienced by the subject during intraocular pressure measurement.

[0084] Furthermore, the intraocular pressure measuring device of this embodiment is equipped with a temperature control means for controlling the driving of the temperature change means. For example, by having a temperature control means along with the temperature change means in the intraocular pressure measuring device, the temperature of the fluid can be maintained at a temperature that is less likely to cause discomfort. For example, by maintaining the temperature of the fluid at a temperature that is considered less likely to cause discomfort, such as body temperature, the discomfort of the subject can be reduced.

[0085] Furthermore, the intraocular pressure measuring device of this embodiment includes a fluid transfer means that stores fluid and transfers it to a fluid discharge means, and is separate from the housing that houses the fluid discharge means, and the temperature changing means is provided in the fluid transfer means. For example, if the temperature changing means is provided in the fluid discharge means, it is necessary to take in new fluid and adjust its temperature each time fluid is discharged. Once fluid is discharged, it takes time to change the temperature of the fluid to be discharged next. However, if the temperature changing means is provided in the fluid transfer means, fluid is stored separately from the discharged fluid, and the temperature of the stored fluid can be adjusted. This makes it possible to efficiently discharge temperature-adjusted fluid when measuring the intraocular pressure of the eye under examination.

[0086] Furthermore, the intraocular pressure measuring device of this embodiment includes a transfer control means for controlling the drive of the fluid transfer means, and the transfer control means pushes the fluid stored in the fluid transfer means to the fluid discharge means. For example, by devising the arrangement of the fluid transfer means with respect to the fluid discharge means, the fluid in the fluid transfer means can be transferred to the fluid in the fluid discharge means. As an example, the fluid heated in the fluid transfer means can be transferred into the fluid discharge means by raising it. In this case, the cold fluid in the fluid discharge means descends into the fluid transfer means and circulates. However, with such a configuration, it takes time for the temperature of the fluid in the fluid discharge means to reach the appropriate temperature. When a transfer control means is provided together with the fluid transfer means, as in this embodiment, the fluid at the appropriate temperature can be efficiently transferred into the fluid discharge means.

[0087] In the intraocular pressure measuring device of this embodiment, the fluid transport means stores the fluid necessary for multiple intraocular pressure measurements of the cornea, and the transport control means pushes out one dose of fluid each time an intraocular pressure measurement is performed. As a result, even when measuring the intraocular pressure of the eye being examined in succession, a temperature-controlled fluid can be used continuously, thereby improving the efficiency and time required for intraocular pressure measurement.

[0088] Furthermore, in the intraocular pressure measuring device of this embodiment, a check valve is provided in the flow path connecting the fluid transport means and the fluid discharge means to suppress backflow of fluid when the fluid transport means is not transporting fluid. This suppresses the possibility that, for example, untemperature-adjusted fluid in the fluid discharge means and temperature-adjusted fluid (for example, fluid kept at a constant temperature) in the fluid transport means will mix, causing the fluid temperature to drop or rise. Alternatively, it suppresses the possibility that temperature-adjusted fluid transported into the fluid discharge means and fluid whose temperature will be adjusted in the fluid transport means will mix, causing the fluid temperature to drop or rise. Therefore, it becomes possible to discharge fluid at a more stable temperature to the eye under examination.

[0089] <Example of transformation> In this embodiment, the intraocular pressure measuring device 1 has the temperature change unit 250 located in the fluid transfer unit 230, but is not limited to this. In this embodiment, the temperature change unit 250 may be located in the fluid discharge unit 200. For example, the heater 251 and thermometer 252 of the temperature change unit 250 may be provided inside the first cylinder 201. In this configuration, the intraocular pressure measuring device 1 does not necessarily have to include the fluid transfer unit 230.

[0090] In this embodiment, the intraocular pressure measuring device has the heater 251 and thermometer 252 of the temperature change unit 250 both located in the fluid transfer unit 230, but is not limited to this. For example, the heater 251 may be located in the fluid transfer means and the thermometer 252 in the fluid discharge means. Of course, the thermometer 252 may be located in both the fluid transfer means and the fluid discharge means.

[0091] The intraocular pressure measuring device 1 of this embodiment is equipped with one fluid transfer unit 230, but is not limited thereto. The intraocular pressure measuring device 1 of this embodiment may be equipped with a plurality of fluid transfer units. In this case, the fluid discharge unit 200 is provided with a first fluid transfer unit and a second fluid transfer unit via a connecting unit. The first fluid transfer unit and the second fluid transfer unit may each have a cylinder, piston, solenoid, etc. Furthermore, the first fluid transfer unit and the second fluid transfer unit may each have a temperature change unit including a heater. The control unit 80 may transfer and discharge temperature-adjusted air by controlling the pressure (positive and negative pressure) in the fluid discharge unit 200, the first fluid transfer unit, and the second fluid transfer unit.

[0092] If the intraocular pressure measuring device has one fluid transport unit 230, once all the air in the fluid transport unit 230 is used up, intraocular pressure cannot be measured while the temperature of the newly drawn-in air via the third check valve 240c is adjusted. This reduces the efficiency of intraocular pressure measurement. However, if the device has multiple fluid transport units, even if all the air in the first fluid transport unit is used up, the air in the second fluid transport unit can be used. That is, while new air is being drawn into the first fluid transport unit and its temperature is being adjusted, the temperature-adjusted air from the second fluid transport unit can be used. For example, by the time the air in the second fluid transport unit is used up, the air in the first fluid transport unit will have been sufficiently warmed. Therefore, the time required to adjust the air in at least one fluid transport unit can be used, improving the efficiency of intraocular pressure measurement. [Explanation of Symbols]

[0093] 1. Intraocular pressure measuring device 80 Control Unit 85 Display section 100 Measuring part 200 Fluid discharge section 230 Fluid transfer section 240 Check valve 250 Temperature change section 260 Connection section

Claims

1. An intraocular pressure measuring device for measuring the intraocular pressure of the eye under examination, A fluid discharge means for discharging fluid onto the cornea of ​​the eye under examination via a nozzle, A temperature changing means for changing the temperature of the fluid discharged from the fluid discharge means, An intraocular pressure measuring device characterized by being equipped with the following features.

2. In the intraocular pressure measuring device according to claim 1, An intraocular pressure measuring device characterized by comprising a temperature control means for controlling the driving of the temperature change means.

3. In the intraocular pressure measuring device according to claim 1 or 2, A fluid transfer means for storing the fluid and transferring it to the fluid discharge means, comprising a fluid transfer means different from the housing in which the fluid discharge means is housed, The intraocular pressure measuring device is characterized in that the temperature changing means is provided in the fluid transfer means.

4. In the intraocular pressure measuring device according to claim 3, The system includes a transfer control means for controlling the drive of the fluid transfer means, The intraocular pressure measuring device is characterized in that the transfer control means pushes the fluid stored in the fluid transfer means to the fluid discharge means.

5. In the intraocular pressure measuring device of claim 4, The fluid transfer means stores the fluid necessary for multiple intraocular pressure measurements of the cornea, The transport control means is characterized by dispensing the fluid one dose at a time each time the intraocular pressure is measured.

6. In an intraocular pressure measuring device according to any one of claims 3 to 5, An intraocular pressure measuring device characterized in that a check valve is provided in the flow path connecting the fluid transfer means and the fluid discharge means to suppress backflow of the fluid when the fluid transfer means is not transferring the fluid.

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