NONINVASIVE NONDISRUPTIVE ASSESSMENT OF EYELID DYNAMICS BY MEANS OF EDDY-CURRENT NO-TOUCH SENSORS

Abstract

Systems and processes for measurement of the eyelid movements of a subject, which explores eyelids' electrical conductivity, namely the established fact that eyelids are acting as sliding electrodes moving over the cornea, is comprised of a system for generating a high frequency weak and harmless oscillating electromagnetic field in the proximity of the eyelid movement path without interference with the vision or activity of any such subject, therefore induces so-called Eddy Currents in the eyelid, which in its turn produce its own electromagnetic field with a value depended on the eyelid position; the interaction between the basic oscillating electromagnetic field and the field generated by the eyelid is changing electromagnetic field inductance, which will be measured with very high accuracy by means of resonance sensing electronics; such systems can transmit data from its detecting electronics to a remote monitor that compels no restrictions on operator activity.

Claims

1. Systems for assessment of displacement of the eyelid of a subject, comprised of: means for generating electromagnetic fields resonant circuit, such electromagnetic field generating means designed to be located proximate the eyelid movement path of any such subject without interference with the vision or activity of any such subject; means for detecting variable electromagnetic fields generated by a moving eyelid in such a generated electromagnetic field, and means for utilizing the information provided by any such detected electromagnetic fields; such systems and processes utilize the fact that eyelids moving over the cornea of an eye act as sliding electrodes which generate currents called Eddy Currents, which in its turn are generating own electromagnetic field that interacts with initial electromagnetic field and the result of this interactions changes the resonant circuit inductance that reveals position of the eyelid to resonant circuit position with the data from such sensing electronics is susceptible of transmission to, or recording by, or display by other systems.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings illustrate complete preferred embodiments of the present invention, by way of example only, according to the best modes presently devised for the practical application of the principles thereof, and in which:

[0031] FIG. 1 schematically illustrates the elements for measuring eyelid dynamics, according to one preferred embodiment of the present invention, in a High Performance Phase Lock Loop (PLL), as explained below;

[0032] FIG. 2 is a photograph illustrating an air-core coil with Inductance-to-Digital Micro-Converter LDC1000, of the present invention, carried for convenience on an eyeglass frame used in the experimental study;

[0033] FIG. 3 presents a computer display graphically showing measurement results of three eye blinks with about 2 second intervals as determined by the eyelid dynamic measuring systems and processes of the present.

DETAILED DESCRIPTION OF THE DRAWINGS

[0034] The elements for measuring eyelid dynamics, according to one preferred embodiment of the present invention is schematically illustrated in FIG. 1. It shows a combined eye with an eyelid (1), which provides the environment for measuring eyelid dynamics according to the systems and processes of the present invention. LC resonator (2), (for example in the form of an air core carried on an eyeglass frame, as shown in FIG. 2), is designed to placed and held in the proximity of eye/eyelid (1). Cristal Oscillator with short term frequency stability. In preferred embodiments of the present invention, changes in frequency detected by the air core are processed through Phase Detector (4), Amplifier (5) and to Loop Filter (6), for transmission to, or recording by, or display by other systems (7).

[0035] It will be appreciated that the Electronic Circuit of FIG. 1 is, in fact, a Phase Locked Loop (PLL) that ensures a precise detection in the change of sensor resonance circuit frequency induced in the air core by proximate eyelid movement.

[0036] On FIG. 2 shows, in addition to the frame (3) and LC-resonator (2), Inductance-to-Digital Micro-Converter (1), such as a tiny commercial off-the-shelf Inductance-to-Digital Micro-Converter, LDC1000 (Texas Instruments), in operative connection with LC-resonator (2), assembled on eyeglass frame (3) with USB connector (4) to a computer

[0037] On FIG. 3 has shown an image of computer displays inductance measurement of three eye blinks profiles on amplified time scale with about 2 sec. interval of a person during a test.

[0038] While the invention has been particularly shown, described and illustrated in detail with reference to preferred embodiments, processes, and modifications thereof, it should be understood by those skilled in the art that the foregoing and other modifications are exemplary only, and that equivalent changes in form and detail may be made therein without departing from the true spirit and scope of the invention as claimed, except as precluded by the prior art.