Sensory aid for visually handicapped people

• US 4,227,209 A
• Filed: 08/09/1978
• Issued: 10/07/1980
• Est. Priority Date: 08/09/1978
• Status: Expired due to Term

• Current Assignee: Charles Stark Draper Laboratory Incorporated
• Original Assignee: Charles Stark Draper Laboratory Incorporated
• Inventors: Warner, David A.
• Primary Examiner(s): Murray, Richard
• Application Number:
  US05/932,271
• Time in Patent Office: 790 Days
• Field of Search: 358/83, 358/94, 358/212, 358/213, 358/240, 358/241, 358/180
• US Class Current: 348/63
• CPC Class Codes: G09G 2340/0407 Resolution change, inclusive of the use of different resolutions for different screen areas
• CPC Class Codes: G09G 2340/14 Solving problems related to the presentation of information to be displayed
• CPC Class Codes: G09G 3/20 for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters

Abstract

A sensory aid system for visually handicapped persons. The system provides a magnified image of graphical material, such as text. The system includes an image sensor which may include a lens assembly and photodiode detector array. The image sensor is coupled to a display array, with each detector array element having a one-to-one correspondence with one (or a group of) display array elements. The display array may be adjusted electronically to provide any degree of magnification simply by changing the number of elements in the array driven by the signal information. The display array elements may be red light emitting diodes (LED'"'"'s). In this form, the present invention provides a magnified brightly illuminated red image of the black areas of print against a black, or dark, background, instead of the conventional text format of black print (information) on white paper (noise).

Claims

1. A sensory aid system for visually handicapped persons, comprising:

an image sensor including a lens assembly adapted to focus a graphic image on a plurality of detector networks, each detector network including means for converting a portion of a graphic image into an electrical signal representative of a picture element of that image, and

display means including an array of display elements wherein at least one of said display elements is coupled to a corresponding one of said detector networks wherein said image sensor further comprises a control means, said control means being operable to couple each of said drive signals to groups of one or more adjacent elements in said detector array wherein the number of display elements in said groups is selectable.

2. A system according to claim 1 wherein said image sensor comprises an array of photodiodes, each element of said photodiode array being a portion of one of said detector networks and being responsive to light from the associated portion of said graphic image, each of said detector networks further including means to generate a picture element signal representative of the intensity of said light from said portion and means to periodically sample and hold said picture element signal to generate a signal for driving at least one corresponding element of said display array.

3. A system according to claim 1 wherein said picture element signal generating means provides signals representative of one of n levels of intensity.

4. A system according to claim 3 where n=2.

5. A system according to claim 1 wherein said picture element signal generating means provides signals representative of one of n levels of intensity.

6. A system according to claim 5 where n=2.

7. A system according to claim 1 wherein said display elements are light emitting diodes (LED'"'"'s) and said drive signal generator is adapted so that portions of said image characterized by relatively low reflectivity are represented in said display array by illuminated LED'"'"'s and portions of said image characterized by relatively high reflectivity are represented in said display array by non-illuminated LED'"'"'s.

10. System according to claim 7 wherein said display means further comprises an output lens adapted for magnification of the image formed by said display array.

11. System according to claim 1 wherein said display means further comprises an output lens adapted for magnification of the image formed by said display array.

12. System according to claim 1 wherein said display means further comprises an output lens adapted for magnification of the image formed by said display array.

13. System according to claim 1 wherein said detector networks are adapted so that portions of said image characterized by relatively low reflectivity are represented in said display by illuminated display elements, and portions of said image characterized by high reflectivity are represented in said display by non-illuminated display elements.

14. System according to claim 13 wherein each of said display elements is one or more light emitting diodes (LED'"'"'s).

15. System according to claim 1 further comprising a means for illuminating said graphic image.

16. System according to claim 1 wherein said picture element signal generating means provides a signal having a first binary value when said light intensity is below a predetermined threshold and a second binary value when said light intensity is above said predetermined threshold.

17. System according to claim 16 wherein said picture element signal generating means further includes means to adjustably select said predetermined threshold.

8. A system according to claim 8 wherein said picture element signal generating means provides signals representative of one of n levels of intensity.

9. A system according to claim 8 where n=2.

18. A method of providing an image of graphical material for visually handicapped people comprising:

converting the image to electric picture element signals by means of an image sensor, each of said picture element signals being representative of the intensity of light from an associated portion of said image.

19. A method of providing an image of graphical material for visually handicapped people comprising:

converting the image to electric picture element signals by means of an image sensor, each of said picture element signals being representative of the intensity of light from an associated portion of said image,

converting said picture element signals to corresponding signals suitable to drive one or more elements of a light emitting diode (LED) array, and coupling said drive signals to said array elements, whereby portions of said image characterized by relatively low reflectivity are represented in said LED array by illuminated LED'"'"'s and portions of said image characterized by relatively high reflectivity are represented in said LED array by non-illuminated LED'"'"'s

wherein said coupling step includes the sub-step of coupling each of said drive signals to a group of adjacent display elements in said array, wherein the number of elements in said groups is selected.

20. A sensory aid system for visually handicapped persons, comprising:

an image sensor including a lens assembly adapted to focus a graphic image on a plurality of detector networks, each detector network including means for converting a portion of a graphic image into an electrical signal representative of a picture element of that image, and

display means including an array of display elements wherein at least one of said display elements is coupled to a corresponding one of said detector networks,

wherein said detector networks and adapted so that portions of said image characterized by relatively low reflectivity are represented in said display by illuminated display elements, and portions of said image characterized by high reflectivity are represented in said display by non-illuminated display elements,

wherein the light from said illuminated display elements is red.

21. System according to claim 20 wherein each of said display elements is one or more light emitting diodes (LED'"'"'s).

22. A system according to claim 20 wherein said image sensor further comprises a control means, said control means being operable to couple each of said drive signals to groups of one or more adjacent elements in said detector array wherein the number of display elements in said groups is selectable.

23. A system according to claim 22 wherein said picture element signal generating means provides signals representative of one of n levels of intensity.

24. A system according to claim 23 where n=2.