Imaging array

• US 4,521,773 A
• Filed: 08/28/1981
• Issued: 06/04/1985
• Est. Priority Date: 08/28/1981
• Status: Expired due to Term

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Lyon, Richard F.
• Primary Examiner(s): Curtis, Marshall M.
• Application Number:
  US06/296,947
• Time in Patent Office: 1,376 Days
• Field of Search: 350/3.70, 350/3.78, 365/49, 365/234, 365/235, 365/127, 365/215, 235/472, 340/710, 340/709, 340/707, 340/706, 340/794, 382/50, 382/68
• US Class Current: 345/166
• 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

Abstract

An imaging array provides a plurality of distinguishable bitmap images and comprises an array of sensor cells capable of sensing radiation. The cells are connected in a manner to form distinguishable bitmap images through a pattern of correspondence among the cells. Each bitmap image formed comprises a combination of one or more cells indicative of detecting an image pixel within a field of array cells that have been nonindicative of such detection. The pattern of correspondence may be one of inhibition of the operation of other cells in the array or one of indication of operation to other cells in the array. Various patterns of correspondence can be created among the cells creative of bitmap images. Bitmap images may consist of combinations of responsive cells within a field of nonresponsive cells in the array. For example, each bitmap image may comprise radiation responsive array cells that have sensed a sufficient quantity of radiation within a field of cells which have not sensed radiation or have been inhibited from sensing radiation. On the other hand, each bitmap image may comprise array cells that have not sensed a sufficient quantity of radiation within a field of cells that have sensed a sufficient quantity of radiation. An application of the imaging array is in an IC chip for a cursor control device or an "optical mouse" for use with an interactive display oriented computer system to provide movement for a visible cursor from position to position on a display screen of such a system.

Claims

1. An imaging array comprising a planar array of optical sensor cells each capable of sensing and converting optical radiation into an electrical output signal when any one of said cells has sensed a predetermined quantity of radiation, a field of contrasting features detectable by said sensor array, the difference in the spatial frequency of said contrasting features in said field relative to the spatial relation of said cells productive of an intermediary pattern comprising at least one detected contrasting feature from said field, circuit means coupled to each of said cells to receive said output signals with the output signals of each of said cells coupled with several of said neighboring cells in said array to alter the output of said neighboring cells resulting in the recognition of said intermediary pattern as being one of a limited plurality of predetermined such patterns.

2. The imaging array of claim 1 wherein the electrical correspondence among said cells is such that at least one of said cells in the array has sensed said predetermined quantity of radiation from said field to produce said output signal and the remainder of the cells in the array either having not sensed said predetermined quantity of radiation from said field to produce said output signal or have been electrically inhibited by a neighboring cell from reporting any sensitization from said field due to receipt of an output signal from said neighboring cell.

3. The imaging array of claim 1 wherein the electrical correspondence among said cells is such that at least one of said cells in the array has not sensed said predetermined quantity of radiation from said field and produce an indication thereof and the remainder of the cells in the array having sensed said predetermined quantity of radiation from said field to enable said nonsensing cells to produce said output signal due to said indication received from said sensing cells.

4. The imaging array of any of the claims 1, 2 and 3 wherein said planar array comprises a linear array of cells.

5. The imaging array of any one of the claims 1, 2 and 3 wherein said sensor cells and circuit means are integrally formed in an integrated circuit chip.

6. The imaging array of any one of the claims 1, 2 and 3 wherein said optically detectable pattern comprises a multitude of uniform spaced features on a contrasting background, means to focus said field onto said sensor array.

8. The imaging array of claim 2 wherein said array comprises a two dimensional array of cells.

31. The imaging array of claim 1 wherein each of said cells comprises a dynamic node, reset means coupled to said dynamic node and capable of charging said dynamic node to a voltage representing a first logic state, photosensitive means coupled to said dynamic node and capable of discharging said dynamic node to a voltage representing a second logic stage, said circuit means includes logic means coupled to said dynamic node to provide said output signal when said dynamic node is at said second state, said output signal coupled to the same logic means of at least one neighborhood cell in said array.

32. In the imaging array of claim 31 wherein said logic means includes an inverter coupled to said dynamic node to provide said output.

33. In the imaging array of claim 31 wherein said logic means includes cross coupled NOR gates, an input of one NOR gate coupled to the output of one sensor cell and at least one other input to said one NOR gate coupled to the output of the other NOR gate, another input to said other NOR gate coupled to the output of at least one other sensor cell.

34. In the imaging array of claim 31 wherein said logic means includes pairs of cross coupled NOR gates, an input of one NOR gate coupled to the output of one sensor cell and at least one other input to said one NOR gate coupled to the output of the other NOR gate of each pair, the output of said one NOR gate coupled to an inverter, the output of said inverter coupled as an input to at least one of said other NOR gates in another of said cross coupled NOR gate pairs.

35. The imaging array of any one of the claims 1, 2 and 3 wherein said planar array comprises a two dimensional array of cells.

7. A imaging array including a field of optically detectable features, said array comprising a planar array of optical sensor cells and capable of recognizing a plurality of distinguishable bitmap images upon relative translation between said array and said field, circuit means coupled to each of said cells to provide a plurality of cell outputs each capable of representing whether a cell has sensed a predetermined quantity of radiation received from said field and providing a corresponding output signal the output signal of each of said cells coupled to at least one neighborhood cell to inhibit the operation of said at least one neighboring cell when said inhibiting cell has sensed said predetermined quantity of radiation, the neighborhood cell inhibition productive of a limited number of said distinguishable bitmap images recognizable from said field.

9. The imaging array of claim 7 wherein said sensor cells and said circuit means are integrally formed in an integrated circuit chip.

10. The imaging array of claim 7 wherein said field comprises a multitude of spatial features on a contrasting background, means to focus said field onto said array.

11. The imaging array of claim 10 wherein said field of spatial features is illuminated from the front surface thereof.

12. The imaging array of claim 10 wherein said field of spatial features is transmissive of illumination through said field.

13. The imaging array of claim 10 wherein said field comprises a plurality of spaced light features on a dark background.

14. The imaging array of claim 10 wherein the spacing between said features is greater than the extent of inhibition across said array but less than the extent of said array.

15. The imaging array of claim 10 wherein said field comprises a plurality of spaced dark features on a light background.

16. The imaging array of any one of the claims 10 to 15 wherein said field comprises uniformly spaced features.

17. The imaging array of any one of the claims 10 to 15 wherein said features consist of spots.

18. The imaging array of claim 7 wherein the extent of said neighborhood cell inhibition is over a substantial portion of said array.

36. The imaging array of claim 7 wherein said array comprises a linear array of cells.

37. The imaging array of claim 7 wherein each of said sensor cells includes threshold means comprising a dynamic node coupled to photosensitive means which is coupled to a reference voltage, reset means coupled to said dynamic node and capable of charging said dynamic node to a voltage representative of a first logic state, said photosensitive means discharging said dynamic node to a voltage representing a second logic state upon receipt of said predetermined quantity of radiation from said field, said circuit means including logic means coupled to said threshold means to produce said output signal when said dynamic node reaches said second logic state, said output coupled to the same logic means of at least one neighborhood cell in said array.

38. In the imaging array of claim 37 wherein said logic means includes an inverter coupled to said dynamic node to provide said output.

39. In the imaging array of claim 37 wherein said logic means includes cross coupled NOR gates, an input of one NOR gate coupled to the output of one sensor cell and at least one other input to said one NOR gate coupled to the output of the other NOR gate, another input to said other NOR gate coupled to the output of at least one other sensor cell.

40. In the imaging array of claim 37 wherein said logic means includes pairs of cross coupled NOR gates, an input of one NOR gate coupled to the output of one sensor cell and at least one other input to said one NOR gate coupled to the output of the other NOR gate of each pair, the output of said one NOR gate coupled to an inverter, the output of said inverter coupled as an input to at least one of said other NOR gates in another of said cross coupled NOR gate pairs.

41. The imaging array of any one of the claims 10 to 15 wherein said field comprises nonuniformly spaced features.

19. An imaging array comprising a plurality of sensor cells capable of sensing and converting optical radiation into an electrical signal, means for presenting a field of features to said array for sensitizing selected ones of said cells based upon the spatial frequency of contrasting features in said field relative to the spatial relation of said array cells so as to be productive of an intermediary pattern comprising at least one contrasting feature from said field detectable by said array, circuit means coupled to said cells, the electrical corrspondence among said cells via said circuit means to inhibit the sensing operation of cells in the array that are in proximity to a cell that has sensed a predetermined quantity of radiation productive of said electrical signal, said inhibition extended over a predetermined extent of the array whereby at least one of said cells in the array has sensed radiation and remaining cells in the array have either not sensed radiation or have been inhibited from sensing radiation, said at least one of said cells thereby producing recognizable bitmap images within the metes and bounds of the array.

20. The imaging array of claim 19 wherein said sensor array comprises a two dimensional array of cells.

21. The imaging array of claim 19 wherein said sensor cells and circuit means are integrally formed in an integrated circuit chip.

22. The imaging array of claim 19 wherein said field comprises a multitude of spatial features on a contrasting background, means to focus said field onto said array.

23. The imaging array of claim 22 wherein said field of spatial features is illuminated from the front surface thereof.

24. The imaging array of claim 22 wherein illumination is transmissive through said field of spatial features.

25. The imaging array of claim 22 wherein said field comprises a plurality of spaced light features on a dark background.

26. The imaging array of claim 22 wherein the spacing between said features is greater than the extent of inhibition across said array but less than the extent of said array.

27. The imaging array of claim 22 wherein said field comprises a plurality of spaced dark features on a light background.

28. The imaging array of any one of the claims 22 to 27 wherein said field comprises uniformly spaced features.

29. The imaging array of any one of the claims 22 to 27 wherein said features consist of spots.

30. The imaging array of claim 19 wherein the extent of inhibition is over a substantial portion of said array.

42. The imaging array of claim 19 wherein said array comprises a linear array of cells.

43. The imaging array of any one of the claims 22 to 27 wherein said field comprises nonuniformly spaced features.

44. An imaging array comprising a planar array of optical sensor cells each capable of sensing and converting optical radiation into an electrical signal, means for presenting a field of contrasting features to said array for sensitizing selected ones of said cells based upon the spatial frequency of contrasting features in said field relative to the spatial relation of said cells so as to be productive of an intermediary pattern detectable by said array, and circuit means coupled to said cells to provide a plurality of cell outputs each capable of representing whether a cell has sensed a predetermined quantity of radiation received from said field and providing a corresponding output signal, the output signal from each of said cells coupled across to at least one neighborhood cell whereby the electrical correspondence due to said output signal cross coupling results in said intermediary pattern being recognized as one of a limited plurality of predetermined bitmap images.

45. The imaging array of claim 44 wherein each of said recognized and predetermined bitmap images is representative of an occurrence of a particular event based upon an instantaneous intermediary pattern developed from said field.

46. The imaging array of claim 44 wherein the electrical correspondence among said cells in said array is such that at least one of said cells has sensed said predetermined quantity of radiation from said field to produce said output signal and the remainder of said cells either having not sensed said predetermined quantity of radiation from said field or have been electrically inhibited by a neighboring cell via said output signal from reporting any sensitization from said field due to said electrical correspondence.

47. The imaging array of claim 44 wherein the electrical correspondence among said cells in said array is such that at least one of said cells has not sensed said predetermined quantity of radiation from said field and the remainder of said cells have sensed said predetermined quantity of radiation from said field and have indicated such to enable said nonsensing cells to produce said output signal due to said electrical correspondence.

48. In an imaging array, a plurality of sensor cells, each cell comprising a dynamic node, reset means coupled to said dynamic node and capable of charging said dynamic node to a voltage representing a first logic state, photosensitive means coupled to said dynamic node and discharging said dynamic node to a voltage representing a second logic state upon receipt of a predetermined quantity of radiation, logic means coupled to said dynamic node to produce an output when said dynamic node reaches said second logic state, the output of said logic means being connected to the input of the same logic means of at least one other of said cells in said array to alter the response of said other cells upon receipt of said output.

49. In the imaging array of claim 48 wherein said logic means comprises cross coupled NOR gates, an input of one NOR gate coupled to the output of one sensor cell and at least one other input to said one NOR gate coupled to the output of the other NOR gate, another input to said other NOR gate coupled to the output of at least one other sensor cell.

50. In the imaging array of claim 48 wherein said logic means comprises pairs of cross coupled NOR gates, an input of one NOR gate coupled to the output of one sensor cell and at least one other input to said one NOR gate coupled to the output of the other NOR gate of each pair, the output of said one NOR gate coupled to an inverter, the output of said inverter coupled as an input to at least one of said other NOR gates in another of said cross coupled NOR gate pairs.

57. In the imaging array of claim 48 wherein said logic means produces an output when said dynamic node reaches said second state and no other input to said logic mens from at least one other of said cells has reached said second logic state to produce a corresponding output.

51. The method of producing distinguishable bitmaps with an array of sensor cells comprising the steps

providing an illuminated pattern comprising a field of features on a contrasting background,

moving the sensor cell array relative to the illuminated pattern,

permitting each cell to sense the presence of radiation reflected from the array pattern whereby some of said cells are responsive and some are nonresponsive,

inhibiting the continuance of the response of cells in proximity of another neighboring cell that senses a sufficient amount of radiation from the array pattern, and

reporting out from each cell as to whether the cell has been either responsive or nonresponsive or inhibited whereby a distinguishable bitmap is produced comprising responsive cells in a field of nonresponsive and inhibited cells.

52. The method of claim 51 which includes the steps of

extending the operation of inhibition of neighboring cells over a predetermined extent of the array of imaging cells.

53. The method of claim 52 which includes the step of

providing spacing of the features in the pattern larger than the extent of inhibition but less than the extent of the array.

54. The method of producing distinguishable bitmaps with a planar array of sensor cells comprising the steps of

providing an illuminated pattern comprising a field of features on a contrasting background,

moving the sensor cell array relative to the illuminated pattern,

permitting each cell to sense the presence of radiation reflected from the array pattern whereby some of said cells are responsive and some are nonresponsive,

correlating the results obtained from each cell with at least one neighboring cell to alter the response state of at least one of the correlation cells if one of said correlation cells has sensed a predetermined quantity of radiation, and

reporting out from each sensor cell as to whether the cell has been either responsive or nonresponsive due to said correlating thereby producing a distinguishable bitmap representation from the array.

55. The method of claim 54 wherein the step of correlating comprises the step of either inhibiting the response state of at least one neighboring cell or enabling the response state of at least one neighboring cell.

56. The method of claim 54 which includes the step of

interpreting each distinguishable bitmap representation to be indicative that an optically sensed event has occurred.

58. In an imaging array, a planar array of optical sensor cells each capable of sensing and converting optical radiation into an electrical signal in response to a field of repetitive contrasting features, the spatial relation of said features and said cells productive of detectable patterns by said cells upon relative positional movement between said field and said array, and circuit means coupled to said cells to provide a plurality of cell outputs each capable of representing whether a cell has sensed a predetermined quantity of radiation received from said field and providing a corresponding output signal the output signal of some of said cells coupled to at least one neighborhood cell in a manner to provide electrical correlation among said cells capable of altering the output of some of said cells whereby said field is recognized as one of limited plurality of predetermined bitmap images.

59. In the imaging array of claim 58 wherein said electrical correlation among said cells is such that at least one of said array has sensed said predetermined quantity of radiation from said field and the remainder of said cells either have not sensed said predetermined quantity of radiation from said field or have been inhibited by a neighboring cell from reporting sensitization from said field due to said correlation whereby said sensing cells are productive of a first state output signal and said remainder cells are productive of a second state output signal, the totality of said output signals forming one of said bitmap images.

60. In the imaging array of claim 58 wherein said electrical correlation among said cells is such that at least one of said cells has not sensed said predetermined quantity of radiation from said field and the remainder of said cells have sensed said predetermined quantity of radiation and have indicated such to said nonsensing cells due to said correlation whereby said nonsensing cells are productive of a first state output signal and said remainder cells are productive of a second state output signal, the totality of said output signals forming one of said bitmap images.

61. In the imaging array of claim 58 wherein said electrical correlation among said cells is such that at least one of said cells in said array has sensed said predetermined quantity of radiation from said field productive of said output signal and the remainder of said cells have not sensed said predetermined quantity of radiation from said field or have been inhibited by a sensing cell output signal from reporting sensitization from said field.

62. In the imaging array of claim 58 wherein said electrical correlation among said cells is such that at least one of said cells has not sensed said predetermined quantity of radiation from said field and the remainder of said cells have sensed said predetermined quantity of radiation and have indicated such to said nonsensing cell, said indication enabling an output signal from said nonsensing cell.

63. In the imaging array of any one of the claims 58 through 62 wherein the extent of said correlation among said cells is determined by how many output signals from neighborhood cells are coupled to each cell representing the neighborhood, said extent governing the types and numbers of said bitmap images that are recognized by said circuit means.