Navigation device including thermal sensor

Patent metadata

Field	Value
Publication number	US-9377366-B2
Application number	US-201313936364-A
Country	US
Kind code	B2
Filing date	Jul 8, 2013
Priority date	Jul 8, 2013
Publication date	Jun 28, 2016
Grant date	Jun 28, 2016

Abstract

A navigation device includes a thermal sensor and a processing unit. The thermal sensor is configured to output temperature readings of a work surface. The processing unit is configured to identify a lift event according to the temperature readings.

First claim

What is claimed is:

1. A navigation device, configured to be operated on a work surface, the navigation device comprising:
a light guide comprising a light emergent surface;
an image sensor facing the light emergent surface and configured to capture reflection images of the work surface according to light emerging from the light emergent surface;
a bolometer facing the same light emergent surface of the same light guide as the image sensor and configured to output temperature readings of the work surface according to the light emerging from the light emergent surface; and
at least one processing unit configured to perform tracking operation according to the reflection images and identify a lift event according to the temperature readings.

2. The navigation device as claimed in claim 1 , wherein the image sensor is a CCD image sensor or a CMOS image sensor.

3. The navigation device as claimed in claim 1 , further comprising a light source configured to illuminate the work surface.

4. The navigation device as claimed in claim 3 , wherein the light guide is configured to direct light emitted by the light source.

5. The navigation device as claimed in claim 1 , wherein the processing unit is configured to calculate a temperature value according to the temperature readings, and identify the lift event according to the temperature value or a temperature variation of the temperature value.

6. The navigation device as claimed in claim 5 , wherein when the temperature value is smaller than or equal to a temperature threshold or when the temperature variation is larger than or equal to a variation threshold, the processing unit identifies that the lift event occurs.

7. The navigation device as claimed in claim 1 , wherein when the processing unit identifies that the lift event occurs, the navigation device enters a sleep mode or a hovering mode.

8. The navigation device as claimed in claim 7 , wherein in the sleep mode the image sensor is disabled and the bolometer is operated continuously.

9. A navigation device, configured to be operated on a work surface, the navigation device comprising:
a light guide comprising a light emergent surface;
a light source configured to emit a main beam to the work surface and the work surface reflecting the main beam to generate a main reflection optical path;
an image sensor
facing the light emergent surface,
located on or outside the main reflection optical path, and
configured to capture reflection images of the work surface according to light emerging from the light emergent surface;

a bolometer facing the same light emergent surface of the same light guide as the image sensor and configured to output temperature readings of the work surface according to the light emerging from the light emergent surface; and
at least one processing unit configured to perform tracking operation according to the reflection images and identify a lift event according to the temperature readings.

10. The navigation device as claimed in claim 9 , wherein the image sensor is a CCD image sensor or a CMOS image sensor.

11. The navigation device as claimed in claim 9 , wherein the processing unit is configured to calculate a temperature value according to the temperature readings, and identify the lift event according to the temperature value or a temperature variation of the temperature value.

12. The navigation device as claimed in claim 11 , wherein when the temperature value is smaller than or equal to a temperature threshold or when the temperature variation is larger than or equal to a variation threshold, the processing unit identifies that the lift event occurs.

13. The navigation device as claimed in claim 9 , wherein when the processing unit identifies that the lift event occurs, the navigation device enters a sleep mode or a hovering mode.

14. The navigation device as claimed in claim 13 , wherein in the sleep mode the image sensor is disabled and the bolometer is operated continuously.

15. A navigation device, operated on a work surface, the navigation device comprising:
a light guide comprising a light emergent surface;
an infrared light source configured to illuminate the work surface;
an image sensor facing the light emergent surface and configured to receive light emerging from the light emergent surface;
a bolometer facing the same light emergent surface of the same light guide as the image sensor and configured to output temperature readings of the work surface according to the light emerging from the light emergent surface; and
a processing unit configured to identify a lift event according to the temperature readings.

16. The navigation device as claimed in claim 15 , wherein the processing unit is configured to calculate a temperature value according to the temperature readings, and identify the lift event according to the temperature value or a temperature variation of the temperature value.

17. The navigation device as claimed in claim 16 , wherein when the temperature value is smaller than or equal to a temperature threshold or when the temperature variation is larger than or equal to a variation threshold, the processing unit identifies that the lift event occurs.

18. The navigation device as claimed in claim 15 , wherein when the processing unit identifies that the lift event occurs, the navigation device enters a sleep mode or a hovering mode.

19. The navigation device as claimed in claim 18 , wherein in the sleep mode the bolometer is operated continuously.

20. The navigation device as claimed in claim 18 , further comprising an accelerometer operating in the hovering mode.

Assignees

• Pixart Imaging Inc

Inventors

• Chia Chin-Wee

Classifications

• G06F3/03543

  Mice or pucks (G06F3/03541 takes precedence) · CPC title

• G06F3/0317 Primary

  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 title

• G06F3/038

  Control and interface arrangements therefor, e.g. drivers or device-embedded control circuitry · CPC title

• G01K3/10 Primary

  in respect of time, e.g. reacting only to a quick change of temperature · CPC title