Applanation tonometer having cornea alignment means
First Claim
1. An applanation tonometer to measure an intraocular pressure of an eye of a patient undergoing testing, said applanation tonometer comprising:
- a light source to generate light, said light source to be aligned with a cornea of the patient'"'"'s eye undergoing testing;
a light-transmitting body having first and opposite ends, a longitudinal axis running between said first and opposite ends, and a circular contact tip located at the first end to be moved into contact with an area of the eye undergoing testing and apply a pressure thereagainst, said circular contact tip being positioned to receive the light generated by said light source and transmitted in a first direction inwardly through said light-transmitting body towards the patient'"'"'s eye and to reflect at least some of the inwardly-transmitted light in a second direction outwardly through said light-transmitting body away from the patient'"'"'s eye depending upon the area of contact between the circular contact tip of said light-transmitting body and the patient'"'"'s eye;
a pair of circular light-blocking disks spaced one behind the other and embedded within the opposite end of said light-transmitting body, each of said pair of circular light-blocking disks having a diameter which is identical to one another and to the diameter of the circular contact tip of said light transmitting body and a light-transmitting channel running through a center thereof and lying along the longitudinal axis of said light-transmitting body so that the light that is generated by said light source is transmitted from said light source in said first direction through the light-transmitting channels of said pair of circular light-blocking disks located at the opposite end of said light-transmitting body to the circular contact tip located at the first end of said light-transmitting body by which the cornea of the eye undergoing testing is illuminated, such that the light with which the cornea is illuminated provides a visual indication to the patient whether said light source and the patient'"'"'s cornea are aligned with one another to enable the intraocular pressure of the patient'"'"'s eye to be measured;
a photo detector to receive the light reflected by said circular contact tip in the second direction outwardly through said light-transmitting body and to provide an output signal in response thereto; and
a force detector to provide an output signal in response to the pressure generated at the area of contact between the circular contact tip of said light-transmitting body and the patient'"'"'s eye.
1 Assignment
0 Petitions
Accused Products
Abstract
An applanation tonometer is disclosed for providing a measurement of intraocular fluid pressure inside the eye of a patient. The applanation tonometer includes a light-transmitting prism having a cornea contact tip at one end and a cornea alignment aid at the opposite end. The cornea alignment aid enables the patient to advise a vision professional when a light source of the tonometer is properly aligned with his cornea so that intraocular fluid pressure can be accurately measured. A light-blocking baffle is located at the opposite end of the prism, and a thin light-transmitting channel is formed through the baffle to lie on the longitudinal axis of the prism. In a preferred embodiment, the light baffle is at least one opaque disk, and the light-transmitting channel is a clear spot at the center of the opaque disk through which light is transmitted to the patient'"'"'s cornea.
5 Citations
6 Claims
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1. An applanation tonometer to measure an intraocular pressure of an eye of a patient undergoing testing, said applanation tonometer comprising:
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a light source to generate light, said light source to be aligned with a cornea of the patient'"'"'s eye undergoing testing; a light-transmitting body having first and opposite ends, a longitudinal axis running between said first and opposite ends, and a circular contact tip located at the first end to be moved into contact with an area of the eye undergoing testing and apply a pressure thereagainst, said circular contact tip being positioned to receive the light generated by said light source and transmitted in a first direction inwardly through said light-transmitting body towards the patient'"'"'s eye and to reflect at least some of the inwardly-transmitted light in a second direction outwardly through said light-transmitting body away from the patient'"'"'s eye depending upon the area of contact between the circular contact tip of said light-transmitting body and the patient'"'"'s eye; a pair of circular light-blocking disks spaced one behind the other and embedded within the opposite end of said light-transmitting body, each of said pair of circular light-blocking disks having a diameter which is identical to one another and to the diameter of the circular contact tip of said light transmitting body and a light-transmitting channel running through a center thereof and lying along the longitudinal axis of said light-transmitting body so that the light that is generated by said light source is transmitted from said light source in said first direction through the light-transmitting channels of said pair of circular light-blocking disks located at the opposite end of said light-transmitting body to the circular contact tip located at the first end of said light-transmitting body by which the cornea of the eye undergoing testing is illuminated, such that the light with which the cornea is illuminated provides a visual indication to the patient whether said light source and the patient'"'"'s cornea are aligned with one another to enable the intraocular pressure of the patient'"'"'s eye to be measured; a photo detector to receive the light reflected by said circular contact tip in the second direction outwardly through said light-transmitting body and to provide an output signal in response thereto; and a force detector to provide an output signal in response to the pressure generated at the area of contact between the circular contact tip of said light-transmitting body and the patient'"'"'s eye. - View Dependent Claims (2, 3, 4, 5, 6)
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Specification