Input device for a computer

• US 6,498,604 B1
• Filed: 05/20/1999
• Issued: 12/24/2002
• Est. Priority Date: 02/12/1997
• Status: Expired due to Fees

• Current Assignee: Kanitech A/S
• Original Assignee: Kanitech A/S
• Inventors: Jensen, Jørgen Korsgaard
• Primary Examiner(s): Hjerpe, Richard
• Assistant Examiner(s): Nguyen, Kevin M.
• Application Number:
  US09/315,664
• Time in Patent Office: 1,314 Days
• Field of Search: 345/179, 345/166, 178/18.01
• US Class Current: 345/179
• 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 3/03543 Mice or pucks G06F3/03541 takes precedence
• CPC Class Codes: G06F 3/03546 using a rotatable ball at the tip as position detecting member

Abstract

The present invention provides an input device for positioning a cursor on a computer screen by movement of a ball whose rotary movements are transformed into electronic signals, which is unique in that the angular rotations of the ball can be detected by an optical detection means by use of substantively coherent light in such a manner that the rotation of the ball is converted into data values with respect to an x-axis and a y-axis, said axes being preferably perpendicular to each other. This provides a compact detecting device which is suitable for the construction of a computer mouse with the shape of a ball-point pen.

Claims

1. An input device for positioning a cursor on a computer screen, the device comprising:

a ball adapted to move on a substrate;

optical detection means for detecting angular rotation of the ball in two dimensions perpendicular to each other, and transforming the angular rotation of the ball in two perpendicular dimensions into electrical signals;

wherein said optical detection means comprises

a first set of detectors adapted to detect an angular rotation in a first of the two perpendicular dimensions, said first set comprising at least two detectors,

a second set of detectors adapted to detect an angular rotation in a second of the two perpendicular dimensions, said second set comprising at least two detectors, and

at least one source of substantially coherent electromagnetic radiation communicating with the first and second sets of detectors through a system of lenses, the system of lenses being common to the first and second sets of detectors and the at least one source of coherent electromagnetic radiation, such that light to both the first and second sets of detectors passes through the common system of lenses, and such that light both from the source and to the detectors passes through the common system of lenses.

2. An input device according to claim 1, wherein the optical detection means is adapted to detect a movement of a speckle pattern generated by coherent electromagnetic radiation from the at least one source of coherent electromagnetic radiation scattered from a surface of the ball.

3. An input device according to claim 1, wherein the at least one source of coherent electromagnetic radiation comprises a laser.

4. An input device according to claims 1, wherein each the first and second sets of detectors comprises two detectors arranged such that a change in a speckle pattern on a surface of the ball caused by the angular rotation of the ball is detected by a first detector in one of the first and second sets and then by a second detector in the one of the first and second sets.

5. An input device according to claim 4, wherein a transit time between detected speckles in the speckle pattern is determined by electronic means.

6. An input device according to claim 1, wherein the ball comprises markings on a surface thereof, the markings being optically detectable by the optical detection means.

7. An input device according to claim 6, wherein an area on the surface of the ball that is illuminated by the coherent radiation has a size that is essentially the same as a size of the markings.

8. An input device according to claim 6, wherein the detection means further comprises a collimating lens.

9. An input device according to claim 6, wherein the ball comprises a core, a marking layer comprising markings, a reflection layer, and a protection layer.

10. An input device according to claim 6, wherein the detection means comprise a CCD camera, and wherein the markings of the ball detectable by CCD camera.

11. An input device according to claim 1, wherein the detectors are arranged in an array to enable detection of a relative movement in both direction and distance of a marking on the ball surface with respect to the detection means.

12. An input device according to claim 1, wherein a beam from the at least one electromagnetic radiation source is split into two or more beams.

13. An input device according to claim 1, wherein the ball is comprised of steel.

14. An input device according to claim 1, wherein the device comprises a pressure sensitivity meter for recording a ball pressure.

15. An input device according to claim 1, wherein the device comprises an accelerometer for measuring an acceleration of the device in up to three dimensions.

16. An input device according to claim 1, wherein the device comprises a substantially tubular housing with the ball rotatably disposed at one end thereof.

17. An input device according to claim 1, wherein the input device further comprises an electronic signal processing unit the electrical signals from the optical detection means into signals corresponding to a direction in which the ball rotates.

18. An input device according to claim 1, wherein a focus of the optical detection means is asymmetrically directed towards a surface of the ball.

19. An input device according to claim 1, wherein the angular rotation of the ball is transferred to two shafts, and wherein the optical detection means detect the angular rotation of the ball by detecting an angular rotation of each of the shafts.

20. An input device according to claim 1, wherein the input device further comprises a battery, and battery capacity measuring means for generating and transmitting a signal indicating a remaining capacity of the battery.

21. An input device according to claim 6, wherein the detection means further comprises a diffractive optical element.

22. An input device according to claim 6, wherein the detection means further comprises a circularising lens.

23. An input device according to claim 6, wherein the detection means further comprises a polarising beam splitter.

24. An input device according to claim 6, wherein the detection means further comprises a quarter wave plate.

25. An input device according to claim 11, wherein the detectors are arranged in a quadratic array.

26. An input device according to claims 19, wherein the shafts are arranged perpendicular to each other.