Portable device for the accurate measurement of eye movements both in light and obscurity

• US 4,102,564 A
• Filed: 02/20/1976
• Issued: 07/25/1978
• Est. Priority Date: 04/18/1975
• Status: Expired due to Term

• Current Assignee: Henry L. Michael
• Original Assignee: Henry L. Michael
• Inventors: Michael, Henry L.
• Primary Examiner(s): Corbin, John K.
• Assistant Examiner(s): Lee, John D.
• Application Number:
  US05/660,030
• Time in Patent Office: 886 Days
• Field of Search: 351/6, 351/7, 351/13, 351/16, 351/38, 248/118, 248/226 A, 297/391, 297/392, 297/406, 297/410, 357/17, 357/18
• US Class Current: 351/210
• CPC Class Codes: A61B 3/113 for determining or recording eye movement

Abstract

A portable device for accurately measuring horizontal and vertical movements of each eye of a subject by reflecting thereon non-modulated invisible infrared light and converting the movements into continuous voltages. The device comprises emitters and detectors, arranged in a fixed spaced relationship and mounted rigidly either on a helmet worn by the subject, a head clamp holding the head immobile, or a separate support outside the subject.

Claims

1. A device for measurement of movements of an eye of a subject comprising support means for engaging the head of a subject in fixed relation therewith, a housing mounted on said support means at a fixed distance from the eye of the subject, two non-modulated infra-red light sources in said housing positioned to direct infra-red beams of light onto the eye of the subject, two sensing means in said housing equally spaced from said sources along a straight line therewith for receiving infra-red light reflected from said eye by the corresponding sources, said sensing means and said light sources being in fixed relationship in said housing, each of said sensing means including an infra-red light filter to pass substantially only infra-red light, said housing having an opening located in the center of the line joining the sources and the sensing means and through which opening a beam of visible light can be directed towards the subject to permit the irradiating infra-red light to correctly fall upon the eye before commencing an operation, means for selectively interrupting said visible light, means for calibrating said housing on said support means for controlling the positioning of said beams from said sources to the eye and thereby the reflected beams from said eye, and non-modulated electronic means connected to said sensing means for producing an output signal, said calibrating means permitting lateral sliding movement of said housing along an axis parallel to said line joining the sources and sensing means and pivotal movement of said housing along an axis parallel to said line.

2. A device as claimed in claim 1 wherein said light sources and said sensing means are disposed on said line for responding to one linear movement of the eye.

3. A device as claimed in claim 2 wherein two of said housings are disposed on said support means, each housing being operative with a respective eye.

4. A device as claimed in claim 2 wherein two further light sources and two further sensing means are disposed on a line perpendicular to said line with the first two light sources and two sensing means thereon.

5. A device as claimed in claim 4 wherein said light sources and sensing means are arranged symmetrically on their respective lines and said lines intersect at a common center, said source of visible light being at said center.

6. A device as claimed in claim 1 wherein said support means comprises a helmet affixable onto the head of the subject, and a rigid bar on said helmet for support of said housing.

7. A device as claimed in claim 1 wherein said sensing means includes means for analog conversion of the sensed infra-red reflected light into said output signal.

8. A device as claimed in claim 1 wherein said support means comprises a rigid first U-tube structure including branches which lie behind the ears of the subject, a curved portion above the head of the subject, said branches having ends inclined toward an object to which said structure is to be secured, supports for the chin and the forehead and flaps secured by straps to hold the top and back of the head of the subject.

9. A device as claimed in claim 8 wherein said support means further comprises a second U-tube structure adjustably secured to the first U-tube structure and projecting in front thereof.