Reading device for the visually handicapped

• US 4,548,485 A
• Filed: 09/01/1983
• Issued: 10/22/1985
• Est. Priority Date: 09/01/1983
• Status: Expired due to Fees

• Current Assignee: Stewart Dean
• Original Assignee: Stewart Dean
• Inventors: Dean, Stewart
• Primary Examiner(s): Frankfort, Charles
• Assistant Examiner(s): Will, Thomas B.
• Application Number:
  US06/528,527
• Time in Patent Office: 782 Days
• Field of Search: 353/67, 353/66, 353/65, 353/63, 353/81, 353/97, 353/79, 350/508, 350/576, 350/301
• US Class Current: 353/67
• CPC Class Codes: G03B 21/06 affording only episcopic projection

Abstract

An optical viewing device enabling visually handicapped persons to read ordinary textual material in full color, the device comprising a stage for holding the material and an X-Y positioner used to move the textual material on the stage; lights beneath the stage for illuminating the material; an objective to form a real image; a prism or mirrors for reflecting the imaging rays from the objective through 90 degrees and for reinverting the rays; two mirrors to reflect the rays to an approximately vertical, directional, controlled brightness rear projection screen, so that the imaging rays successively passing from the objective to the reflecting/reinverting prism or mirrors and the two mirrors form a real, erect enlarged image on the screen.

Claims

1. An optical viewing device to enable a visually handicapped person to read ordinary textual material, the device comprising a substantially horizontal stage for holding the textual material;

means for moving the textual material parallel to the stage;

means below the stage for illuminating the material on the stage;

an objective to form imaging rays and provide a real image of the material;

means for both reflecting the imaging rays from the objective through substantially 90 degrees and reinverting the imaging rays;

a first reflecting surface;

a second reflecting surface; and

a substantially vertically oriented, directional, controlled brightness rear projection viewing screen, the imaging rays from the objective successively passing from the reflecting means and the first and second surfaces to form a real erect enlarged image of the material as viewed from the front of the screen.

2. A device according to claim 1 wherein the image brightness on the screen is from about 2.5 to about 400 foot-candles.

3. A device according to claim 2 wherein the brightness is measured normal to the screen.

4. A device according to claim 1 wherein the surface of the screen initially receiving the imaging rays comprises a lenticular material.

5. A device according to claim 1 wherein the surface of the screen initially receiving the imaging rays comprises a plurality of parallel substantially semi-cylindrical transparent ridges.

6. A device according to claim 1 wherein the surface of the screen initially receiving the imaging rays comprises a Fresnel lens.

7. A device according to claim 1 wherein the image is from 5 to 30 diameters larger than the original material.

8. A device according to claim 1 wherein the reflecting surfaces are first-surface mirrors.

9. A device according to claim 1 wherein the reflecting surfaces are planar.

10. A device according to claim 1 wherein the reflecting means is an Amici prism.

11. A device according to claim 1 wherein the reflecting means is two mirrors disposed at right angles to each other.

12. A device according to claim 1 wherein the stage includes means for moving the textual material in two dimensions parallel to the stage and maintaining the material a substantially constant distance from the objective.

13. A device according to claim 1 including means for forced air cooling of the illuminating means and means for shutting off the illuminating means when the cooling means is inoperative.

14. A device according to claim 1 wherein the screen is vertically above the stage.

15. A device according to claim 1 wherein a secondary objective is used to modify the real image formed by the objective.