Pointing device utilizing a photodector array

• US 5,854,482 A
• Filed: 03/28/1997
• Issued: 12/29/1998
• Est. Priority Date: 10/05/1992
• Status: Expired due to Term

• Current Assignee: Logitech Europe S A (Logitech International SA)
• Original Assignee: Logitech, Inc. (Logitech International SA)
• Inventors: Bidiville, Marc, O'Keeffe, Denis, Raeber, Eric, Buczek, Harthmuth, Van Shaik, Floris A., Arreguit, Javier, Bauduin, Fran.cedilla.ois
• Primary Examiner(s): Westin, Edward P.
• Assistant Examiner(s): Lee, John R.
• Application Number:
  US08/825,435
• Time in Patent Office: 641 Days
• Field of Search: 250/221, 250/222.1, 250/229, 250/559.36, 250/559.29, 345/156, 345/157, 345/158, 345/159, 345/160, 345/161, 345/162, 345/163, 345/164, 345/165, 345/166, 345/167, 345/168, 345/169, 345/170, 345/171, 345/172, 356/373, 356/375, 356/376
• US Class Current: 250/221
• CPC Class Codes: G06F 1/1613 for portable computers cooling arrangements therefor G06F1/203; constructional details or arrangements for pocket calculators, electronic agendas or books G06F15/0216; constructional details of portable telephone sets: with several bodies H04M1/0202
• CPC Class Codes: G06F 1/169 the I/O peripheral being an integrated pointing device, e.g. trackball in the palm rest area, mini-joystick integrated between keyboard keys, touch pads or touch stripes G06F1/1643 takes precedence; constructional details of pointing devices G06F3/033
• CPC Class Codes: G06F 2203/0338 Fingerprint track pad, i.e. fingerprint sensor used as pointing device tracking the fingertip image
• CPC Class Codes: G06F 3/0312 for tracking the rotation of a spherical or circular member, e.g. optical rotary encoders used in mice or trackballs using a tracking ball or in mouse scroll wheels tracking relative movement in co-operation with a regularly or irregularly patterned surface, e.g. as in optical mice G06F3/0317; constructional details of scroll or thumb-wheels G06F3/0362; optical rotary encoders G01D5/3473
• CPC Class Codes: G06F 3/0317 in co-operation with a patterned surface, e.g. absolute position or relative movement detection for an optical mouse or pen positioned with respect to a coded surface
• CPC Class Codes: G06F 3/03543 Mice or pucks G06F3/03541 takes precedence
• CPC Class Codes: G06F 3/03547 Touch pads, in which fingers can move on a surface
• CPC Class Codes: G06F 3/03549 Trackballs G06F3/03541 takes precedence
• CPC Class Codes: G06F 3/0383 Signal control means within the pointing device

Abstract

A cursor control device for personal computers and workstations includes various embodiments, some of which include a patterned ball and some of which rely on other patterned surfaces, which recognizes changes in the position of the pattern relative to a sensor having an array of photosensitive elements. Circuitry associated with the sensor determines movement of the pattern across the array, and translates that movement into conventional cursor control signals supplied to a host system.

Claims

1. An optical sensor for detecting radiation reflected off of a surface, said optical sensor comprising:

a plurality of pixels, responsive to said radiation reflected from the surface, each of said pixels includes;

a photodetector element for receiving said radiation reflected from said surface and for converting said radiation into an electrical signal having an signal strength corresponding to an intensity of said received radiation;

a first memory unit for storing a first intensity value of said pixel representing the intensity of radiation received by said photodetector element at a first time;

a second memory unit for storing a second intensity value of said pixel representing the intensity of radiation received by said photodetector element at a second time;

a first comparator, disposed to receive signals from said first memory unit, for identifying that an edge condition occurred between said first time and said second time if a ratio between said first and second intensity values is not within a predefined range.

2. The optical sensor of claim 1, wherein each of said pixels further comprises:

a second comparator, disposed to receive an adjacent pixel signal from an adjacent pixel of each of said plurality of pixels representing an intensity of radiation received by said adjacent pixel, for comparing a signal representing one of said first and second intensity values with said adjacent pixel signal to identify one of said edge condition and a direction of said edge condition.

3. The optical sensor of claim 2, wherein said second comparator determines that an edge condition exists if a ratio of said first intensity value and said second intensity value is not within a predefined range.

4. The optical sensor of claim 1, wherein said surface has a plurality of patterns which appear light and dark when illuminated by said radiation.

5. The optical sensor of claim 4, wherein said surface is part of a ball.

6. The optical sensor of claim 1, wherein said surface reflects one of coherent radiation and partially coherent radiation to create speckle patterns when received by said pixels.

7. A method for detecting radiation reflected off of a surface by a plurality of pixels, comprising the steps of:

receiving said radiation reflected from said surface at a pixel;

converting said radiation into an electrical signal having an signal strength corresponding to an intensity of said received radiation;

storing a first intensity value of said pixel representing the intensity of radiation received by said photodetector element at a first time;

storing a second intensity value of said pixel representing the intensity of radiation received by said photodetector element at a second time; and

identifying that an edge condition occurred between said first time and said second time if a ratio between said first and second intensity values is not within a predefined range.

8. The method of claim 7, further comprising the steps of:

receiving an adjacent pixel signal from an adjacent pixel of each of said plurality of pixels representing an intensity of radiation received by said adjacent pixel; and

comparing a signal representing one of said first and second intensity values with said adjacent pixel signal to identify one of said edge condition and a direction of said edge condition.

9. The method of claim 8, wherein said step of comparing a signal comprises the step of:

determining if a ratio of said first intensity value and said second intensity value is not within a predefined range.

10. The method of claim 7, wherein said surface has a plurality of patterns which appear light and dark when illuminated by said radiation.

11. The method of claim 10, wherein said surface is part of a ball.

12. The method of claim 7, wherein said surface reflects one of coherent radiation and partially coherent radiation to create speckle patterns when received by said pixels.

13. An optical system for detecting radiation reflected off of a surface by a plurality of pixels, comprising:

first receiving means, for receiving said radiation reflected from said surface at a pixel;

converting means, converting said radiation into an electrical signal having an signal strength corresponding to an intensity of said received radiation;

first storing means, for storing a first intensity value of said pixel representing the intensity of radiation received by said photodetector element at a first time;

second storing means, for storing a second intensity value of said pixel representing the intensity of radiation received by said photodetector element at a second time; and

first detecting means, for identifying that an edge condition occurred between said first time and said second time if a ratio between said first and second intensity values is not within a predefined range.

14. The optical system of claim 13, further comprising:

second receiving means, for receiving an adjacent pixel signal from an adjacent pixel of each of said plurality of pixels representing an intensity of radiation received by said adjacent pixel; and

first comparing means, for comparing a signal representing one of said first and second intensity values with said adjacent pixel signal to identify one of said edge condition and a direction of said edge condition.

15. The optical system of claim 14, wherein said comparing means includes:

determining means, for determining if a ratio of said first intensity value and said second intensity value is not within a predefined range.

16. The optical system claim 13, wherein said surface has a plurality of patterns which appear light and dark when illuminated by said radiation.

17. The optical system of claim 16, wherein said surface is part of a ball.

18. The optical system of claim 13, wherein said surface reflects one of coherent radiation and partially coherent radiation to create speckle patterns when received by said pixels.

19. An optical sensor for detecting radiation reflected off of a surface, said optical sensor comprising:

a plurality of pixels, responsive to said radiation reflected from the surface, each of said pixels includes;

a photodetector element for receiving said radiation reflected from said surface and for converting said radiation into an electrical signal having an signal strength corresponding to an intensity of said received radiation; and

a first comparator, disposed to receive an adjacent pixel signal from an adjacent pixel of said pixel representing an intensity of radiation received by said adjacent pixel, for comparing a signal representing said first intensity value with said adjacent pixel signal to identify one of an edge condition and a direction of said edge condition.

20. The optical sensor of claim 19, wherein each of said pixels further comprises:

a first memory unit for storing a first intensity value of said pixel representing the intensity of radiation received by said photodetector element at a first time;

a second memory unit for storing a second intensity value of said pixel representing the intensity of radiation received by said photodetector element at a second time;

a second comparator, disposed to receive signals from said first memory unit, for identifying that said edge condition occurred between said first time and said second time if a ratio between said first and second intensity values is not within a predefined range.

21. The optical sensor of claim 19 wherein said first comparator determines that an edge condition exists if a ratio of said first intensity value and said second intensity value is not within a predefined range.

22. The optical sensor of claim 19, wherein said surface has a plurality of patterns which appear light and dark when illuminated by said radiation.

23. The optical sensor of claim 21, wherein said surface is part of a ball.

24. The optical sensor of claim 19, wherein said surface reflects one of coherent radiation and partially coherent radiation to create speckle patterns when received by said pixels.