Self-operable tonometer for measuring intraocular pressure of a patient's eye

A tonometer for measuring intraocular pressure (IOP) of a patient's eye, the tonometer comprising:

• a probe for contacting the eye, the probe being movable relative to the eye while in contact with the eye, wherein the probe has a flat, transparent window with a known delimited calibration area such that a contact area between the probe and the eye can be compared to the calibration area to determine areas of applanation;
• a transducer coupled to the probe and including circuitry for providing a digital force signal indicating a force with which the probe contacts the eye;
• a light emitter for emitting light toward the eye;
• a camera for receiving light reflected from the eye and for providing a digital video image data indicating an area of applanation;
• and
• a processor for receiving digital force signals and digital video image data and for determining IOP in response thereto.

A tonometer for measuring intraocular pressure (IOP) of a patient's eye, the tonometer comprising:

• a probe for contacting the eye with a force and for deforming an area of the eye, the probe being movable relative to the eye when in contact with the eye so that the force and area can vary;
• a transducer coupled to the probe for providing force signals indicative of forces with which the probe contacts the eye;
• an optical detector for providing area signals indicative of areas of contact between the probe and the eye;
• and
• a processor, responsive to the force and area signals, for using a plurality of force and area signals to determine IOP, the processor receiving force signals at a first constant rate and area signals at a second constant rate different from the first constant rate, the processor synchronizing the force and area signals.

A method for measuring an intraocular pressure (IOP) of a patient's eye with a device including a probe for contacting the eye with a varying force and for deforming the eye with a varying area, a force sensor for determining forces with which the probe contacts the eye, and an area sensor for determining areas of flattening of a cornea of the patient's eye, the method comprising the computer-implemented steps of:

• measuring, at a first constant rate, a plurality of forces representing forces with which the probe contacts the eye;
• measuring, at a second constant rate different from the first rate, a plurality of areas representing areas of deformation of the eye when the probe contacts the eye;
• and
• determining a value of IOP based on a plurality of force signals and a plurality of area signals.

A tonometer for measuring intraocular pressure (IOP) of a patient's eye, the tonometer comprising:

• a probe for contacting the eye;
• a transducer, coupled to the probe in an easily removable and reattachable manner, for determining a force with which the probe contacts the patient's eye and for providing a force signal, the transducer including a stationary plate and a movable plate that form a variable capacitor, the probe being attached to the movable plate such that deflections of the movable plate causes changes in the capacitance of the variable capacitor;
• an optical system for determining an area of applanation when the probe contacts the eye and for providing an area signal indicative of the area;
• and
• a processor for receiving the force signal and the area signal and for determining IOP in response thereto.

A tonometer for measuring intraocular pressure (IOP) of a patient's eye, the tonometer comprising:

• a probe for contacting the eye, the probe being movable relative to the eye while in contact with the eye;
• a transducer coupled to the probe, the transducer including a first movable plate coupled to the probe, and a second stationary plate substantially parallel to the first movable plate, the first and second plates forming a variable capacitor;
• circuitry coupled to the transducer for providing a force signal indicating a force with which the probe contacts the eye;
• a light emitter for emitting light toward the eye;
• an optical detector for receiving light reflected from the eye and for providing area data indicating an area of applanation;
• and
• a processor for receiving the force signals and area data and for determining IOP in response thereto.

A tonometer for measuring intraocular pressure (lOP) of a patient's eye, the tonometer comprising:

• a probe for contacting the eye, the probe being movable relative to the eye while in contact with the eye and having a transparent window with a known delimited calibration area such that a contact area between the probe and the eye can be compared to the calibration area to determine areas of applanation;
• a transducer coupled to the probe;
• circuitry coupled to the transducer for providing a force signal indicating a force with which the probe contacts the eye;
• a light emitter for emitting light toward the eye;
• an optical detector for receiving light reflected from the eye and for providing area data indicating an area of applanation;
• and
• a processor for receiving the force signals and the area data and for determining IOP in response thereto.