OPTICAL MOUSE WITH LIMITED WAVELENGTH OPTICS

• US 20090153486A1
• Filed: 12/18/2007
• Published: 06/18/2009
• Est. Priority Date: 12/18/2007
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Bohn, David
• Granted Patent: US 8,847,888 B2
• Time in Patent Office: Days
• 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
• CPC Class Codes: G06F 3/03543 Mice or pucks G06F3/03541 takes precedence

Abstract

Various embodiments of optical mice are disclosed that facilitate off-surface detection while also providing high-contrast images of a tracking surface. In one embodiment, an optical mouse comprises a light source configured to emit light having a wavelength in or near a blue region of a visible light spectrum toward a tracking surface, an image sensor, and an optical band pass filter configured to pass the light having the wavelength in or near the blue region of the visible light spectrum emitted by the light source while filtering red and infrared wavelengths. Further, the mouse also comprises a controller configured to receive image data from the image sensor and to identify a tracking feature in the image data. The band pass filter prevents ambient light in the filtered wavelengths from reaching the image sensor, and thereby facilitates off-surface detection, while the blue color of the incident light and band pass filter provides a high-contrast image for motion tracking.

Claims

1. An optical mouse, comprising

a light source configured to emit light having a wavelength in or near a blue region of a visible light spectrum toward a tracking surface;

an image sensor;

an optical band pass filter disposed optically between the tracking surface and the image sensor and configured to pass the light having the wavelength in or near the blue region of the visible light spectrum emitted by the light source; and

a controller configured to receive image data from the image sensor and to identify a tracking feature in the image data.

2. The optical mouse of claim 1, wherein the controller is configured to detect an off-surface condition based upon an amount of light reaching the image sensor.

3. The optical mouse of claim 1, wherein the band pass filter comprises a window that forms a portion of a bottom surface of the mouse.

4. The optical mouse of claim 1, wherein the band pass filter comprises one or more of a coating on a lens disposed optically between the tracking surface and the image sensor and a coating on the image sensor.

5. The optical mouse of claim 1, wherein the optical mouse has a specular architecture.

6. The optical mouse of claim 1, wherein the optical mouse has an oblique architecture.

7. The optical mouse of claim 1, wherein the light source is configured to emit white light.

8. The optical mouse of claim 1, wherein the light source is configured to emit blue light.

9. An optical mouse, comprising

a light source configured to emit light having a wavelength in the range of 400-490 nm toward a tracking surface;

an image sensor;

an optical band pass filter disposed optically between the tracking surface and the image sensor and configured to pass the wavelength of light emitted by the light source to the image sensor while blocking red and infrared wavelengths; and

a controller configured to detect an off-tracking-surface condition of the mouse based upon an amount of light that reaches the image sensor.

10. The optical mouse of claim 9, wherein the mouse has a specular optical architecture.

11. The optical mouse of claim 9, wherein the mouse has an oblique optical architecture.

12. The optical mouse of claim 9, wherein the light source is configured to emit light in a wavelength range of 400-490 nm.

13. The optical mouse of claim 9, wherein the band pass filter comprises a window that forms a portion of a bottom surface of the mouse.

14. The optical mouse of claim 9, wherein the band pass filter comprises one or more of a coating on a lens disposed optically between the tracking surface and the image sensor and a coating on the image sensor.

15. In an optical mouse comprising a light source and an image sensor, a method of operating the mouse, comprising:

illuminating a tracking surface with light from the light source having a wavelength in or near a blue region of the visible light spectrum;

filtering light reflected by the tracking surface toward the image surface to block red and infrared wavelengths of light while passing the light having the wavelength in or near the blue region of the visible light spectrum emitted by the light source;

detecting an off-surface condition based upon a reduction in an amount of light that reaches the image sensor; and

changing an operating condition of the mouse upon detecting the off-surface condition.

16. The method of claim 15, wherein modifying an operating condition of the mouse comprises switching the mouse to a low-power mode.

17. The method of claim 15, wherein modifying an operating condition of the mouse comprises ceasing a tracking of motion of the mouse.

18. The method of claim 17, further comprising detecting an on-surface condition and then resuming tracking of motion of the mouse.

19. The method of claim 15, wherein illuminating a tracking surface with light from the light source having a wavelength in or near a blue region of the visible light spectrum comprises illuminating the tracking surface with light comprising one or more bands in a wavelength range of 400-490 nm.

20. The method of claim 15, wherein filtering light reflected by the tracking surface comprises passing light in a band located within a wavelength range of 400-490 nm.