Computer input device using orientation sensor

• US 5,363,120 A
• Filed: 09/27/1993
• Issued: 11/08/1994
• Est. Priority Date: 10/14/1987
• Status: Expired due to Term

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: Wang Laboratories Incorporated
• Inventors: Drumm, Donald E.
• Primary Examiner(s): Yusko, Donald J.
• Assistant Examiner(s): Holloway, III, Edwin C.
• Application Number:
  US08/128,043
• Time in Patent Office: 407 Days
• Field of Search: 345/163, 345/164, 345/165, 345/166, 345/157, 345/158, 340/686, 340/689, 349/20, 349/21, 73/653, 73/655, 73/505, 200/52 A, 200/61.45 R, 200/61.52, 200/6 A, 200/61.46, 200/61.47, 200/61.83, 200/61.1, 200/220, 273/148 B, 250/221, 250/573, 250/574, 250/575, 250/577, 33/365, 33/366, 33/377
• US Class Current: 345/158
• 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 3/0346 with detection of the device orientation or free movement in a 3D space, e.g. 3D mice, 6-DOF [six degrees of freedom] pointers using gyroscopes, accelerometers or tilt-sensors

Abstract

A hand-held device for controlling cursor movement on a data terminal having a display. An internal orientation sensor provides an electrical signal that is related to the orientation of the device without it being adjacent to any fixed surface. The orientation sensor includes a hollow spherical housing having at least one LED and one phototransistor mounted opposingly in the inner wall, along an axis extending through the center point of the housing. The housing is half-filled with a transparent liquid having a specified viscosity and index of refraction and half-filled with air. A light beam emitted from the LED is refracted upon passing through the boundary between the air and the liquid. As the orientation sensor rotates with respect to the vertical axis, the changing refraction angle of the light beam causes the phototransistor to detect changing intensities of light, which are representative of the angle of rotation.

Claims

1. A graphics system for displaying a cursor and providing controlled movement of the cursor, comprising:

a display terminal unit having a display screen;

a computer, coupled to said display terminal unit, programmed to control the position of a cursor on the display screen in response to cursor control signals;

a computer input device coupled to said computer, the computer input device sensing angular orientation at the input device independently of the computer;

the computer input device generating electrical signals representative of the angular orientation of the input device with respect to a vertical axis passing therethrough for a continuous range of angles and for a continuous range of directions; and

means, coupled to said computer, for generating cursor control signals for controlling the position of a cursor in response to said electrical signals.

2. A system input device as recited in claim 1, wherein said computer input device includes command switch means for initiating computer command signals.

3. A system as recited in claim 1, wherein said computer input device includes trigger switch means, electrically coupled to the interface means, for initiating a subprogram for controlling cursor speed.

4. A system as recited in claim 1, wherein said input device includes:

a housing having a circular cross section and center point in a plane which includes said vertical axis;

a first light source and a first photodetector mounted opposingly in the plane of the circular cross section of the housing on a first axis extending through the center point of the circular cross section;

a second light source and a second photodetector mounted opposingly in the plane of the circular cross section of the housing on a second axis extending through the center point of the circular cross section, the second axis being displaced from the first axis;

a liquid medium and a gaseous medium within the housing, said media having a boundary surface therebetween; and

differential amplifier means, coupled to said photodetector;

whereby the output of the differential amplifier is representative of the magnitude and direction of angular displacement of the input device within said plane.

5. A system as recited in claim 4, wherein the boundary surface between the liquid medium and gaseous medium intersects the center point of the circular cross section.

6. A system as recited in claim 4, wherein said second axis is displaced 90 degrees from said first axis.

7. A system as recited in claim 4, wherein said housing is spherical.

8. A system as recited in claim 4, wherein said light sources are light emitting diodes.

9. A system as recited in claim 4 wherein said photodetectors are phototransistors.

10. A system as recited in claim 4, wherein said liquid medium is castor oil.

11. A system as recited in claim 4, wherein said liquid medium is mineral oil.

12. A computer input device, comprising:

a housing;

sensor means, within the housing, for sensing the magnitude and direction of angular displacement of the housing for a continuous range of angles and for a continuous range of directions relative to a vertical axis and generating electrical signals representative thereof; and

interface means, coupled to the sensor means, for translating said electrical signals into position control signals for transmission to a computer.

13. An input device as recited in claim 12, further including switch means for initiating computer command signals.

14. An input device as recited in claim 12, further including trigger switch means, electrically coupled to said interface means, for initiating a subprogram for controlling cursor speed.

15. An input device as recited in claim 12, wherein said sensor means includes:

a sensor housing having a circular cross section and center point in a plane which includes said vertical axis;

a first light source and a first photodetector mounted opposingly in the plane of the circular cross section of the housing on a first axis extending through the center point of the circular cross section;

a second light source and a second photodetector mounted opposingly in the plane of the circular cross section of the housing on a second axis extending through the center point of the circular cross section, the second axis being displaced from the first axis;

a liquid medium and a gaseous medium within the sensor housing, said media having a boundary surface therebetween; and

differential amplifier means, coupled to said photodetectors;

whereby the output of the differential amplifier is representative of the magnitude and direction of angular displacement of the input device within said plane.

16. An input device as recited in claim 15, wherein the boundary surface between the liquid medium and gaseous medium intersects the center point of the circular cross section.

17. An input device as recited in claim 15, wherein said second axis is displaced 90 degrees from said first axis.

18. An input device as recited in claim 15, wherein said housing is spherical.

19. An input device as recited in claim 15, wherein said light sources are light emitting diodes.

20. An input device as recited in claim 15 wherein said photodetectors are phototransistors.

21. An input device as recited in claim 15, wherein said liquid medium is castor oil.

22. An input device as recited in claim 15, wherein said liquid medium is mineral oil.

23. An input device as recited in claim 12, wherein said sensor means includes:

a spherical housing having a center point defined therein which includes said vertical axis;

four light source/photodetector pairs, each pair mounted opposingly on an axis extending through the center point of the spherical housing and evenly spaced therearound;

said light source/photodetector pairs being arranged, within said spherical housing, with the light sources in the upper hemisphere and the photodetectors in the lower hemisphere;

said housing having a first vertical plane defined therein which includes two light source/photodetector pairs, and a second vertical plane defined therein which includes two other pairs, the planes intersecting orthogonally at the center point;

a liquid medium and a gaseous medium, within the housing, having a boundary surface therebetween which intersects the center point of the circular cross section; and

first differential amplifier means, coupled to the photodetector in the first plane;

second differential amplifier means, coupled to the photodetectors in the second plane;

whereby the output of the first and second differential amplifiers is representative of the magnitude and direction of angular displacement of the spherical housing in any direction with respect to said vertical axis.

24. A method for controlling the position of a cursor on a display screen, comprising the steps of:

sensing the magnitude and direction of angular displacement of a user-movable housing for a continuous range of angles with respect to a reference axis passing through said housing for a continuous range of directions;

generating electrical signals representative of said magnitude and direction; and

translating said electrical signals into digital cursor position control signals for transmission to a computer.