INPUT DEVICE WITH PHOTODETECTOR PAIRS

• US 20110316776A1
• Filed: 06/24/2010
• Published: 12/29/2011
• Est. Priority Date: 06/24/2010
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Inventors: Ong, Chi-Boon, Yao, Yu-Feng, Ong, Sze-Ping
• Granted Patent: US 8,711,093 B2
• Time in Patent Office: Days
• US Class Current: 345/158
• CPC Class Codes: G06F 3/0304 Detection arrangements using opto-electronic means constructional details of pointing devices not related to the detection arrangement using opto-electronic means G06F3/033; optical digitisers G06F3/042
• CPC Class Codes: G06F 3/033 Pointing devices displaced or positioned by the user , e.g. mice, trackballs, pens or joysticks; Accessories therefor digitisers characterised by the transducing means G06F3/041
• CPC Class Codes: G06F 3/042 by opto-electronic means

Abstract

Input devices configured to provide user interface by detecting three dimensional movement of an external object are disclosed. The input device comprises at least two photodetector pairs, a radiation source and a circuit configurable to detect differential and common mode signals generated in the photodetector pairs. By detecting the common mode and differential signals, movement of an external object may be determined and used to control a pointer, or a cursor.

Claims

1. An input device configured to provide user interface by detecting three dimensional movement of an external object, comprising:

a substrate;

a radiation source located on the substrate, the radiation source configured to emit a radiation;

a first photodetector pair located on the substrate with the radiation source located between the first photodetector pair, wherein the first photodetector pair and the radiation source are positioned along a first axis, and wherein the first photodetector pair are configured such that movement of the external object along the first axis is operable to cause more photo signal to be generated in one photodetector of the first photodetector pair and less photo signal to be generated in the other photodetector of the first photodetector pair;

a second photodetector pair located on the substrate with the radiation source located between the second photodetector pair, wherein the second photodetector pair and the radiation source are positioned along a second axis perpendicular to the first axis, and wherein the second photodetector pair are configured such that movement of the external object along the second axis is operable to cause more photo signal to be generated in one photodetector of the second photodetector pair and less photo signal to be generated in the other photodetector of the second photodetector pair; and

a circuit configured to detect movement of the external object, wherein movement of the external object along the first axis is detected through photo signals generated in the first photodetector pair, movement of the external object along the second axis is detected through photo signals generated in the second photodetector pair, and movement along an axis perpendicular to the first and second axes is detected through photo signals generated in both the first and second photodetectors pair.

2. The input device of claim 1 further comprising:

a third photodetector pair located on the substrate with the radiation source located between the third photodetector pair, wherein the third photodetector pair and the radiation source are positioned along a third axis, and movement of the external object along the third axis is operable to cause more photo signal to be generated in one photodetector of the third photodetector pair and less photo signal to be generated in the other photodetector of the third photodetector pair; and

a fourth photodetector pair located on the substrate with the radiation source located between the fourth photodetector pair, wherein the fourth photodetector pair and the radiation source are positioned along a fourth axis, and movement of the external object along the fourth axis is operable to cause more photo signal to be generated in one photodetector of the fourth photodetector pair and less photo signal to be generated in the other photodetector of the fourth photodetector pair,

wherein the third and fourth axes are position on the same plane as the first and second axes, and wherein movement of the external object along the third axis is detected through photo signals generated in the third photodetector pair, movement of the external object along the fourth axis is detected through photo signals generated in the fourth photodetector pair, and movement along an axis perpendicular to the third and fourth axes is detected through photo signals generated in both the third and fourth photodetector pairs.

3. The input device of claim 1, further comprising a top plate positioned above the substrate, wherein the top plate is planarly parallel to the substrate.

4. The input device of claim 3, further comprising a sensor configured to produce an output when the external object touches the top plate.

5. The input device of claim 1, wherein the circuit comprises a differential amplifier.

6. The input device of claim 1, wherein the input device further comprises a reflector dome positioned above the radiation source, the first and second photodetector pairs, wherein the reflector dome is configured to reflect the radiation from the radiation source to the first and second photodetectors pair.

7. The input device of claim 6, wherein the external object compresses the reflector dome causing more radiation to be reflected onto all, or a portion of the first or second photodetector pairs.

8. The input device of claim 1, wherein the radiation emitted by the radiation source has a wavelength between 450 nm to 950 nm.

9. The input device of claim 1, wherein the input device further comprises an indicating light source configured to provide indication when the external objected is detected.

10. The input device of claim 1, wherein the input device forms a portion of a three dimensional navigation device.

11. The input device of claim 1, wherein the input device forms a portion of a mobile device.

12. A navigation input device configured to provide user interface by detecting three dimensional movement of an external object, comprising:

a substrate;

a radiation source located on the substrate, the radiation source configured to emit a radiation;

a first photodetector pair located on the substrate with the radiation source located in the middle of the first photodetector pair, wherein the first photodetector pair and the radiation source positioned to form a first axis, and movement of the external object along the first axis is operable to cause more photo signal to be generated in one photodetector of the first photodetector pair and less photo signal to be generated in the other photodetector of the first photodetector pair;

a first circuit electrically coupled to the first photodetector pair, the first circuit configured to produce a first output signal which correlates to movement of the external object along the first axis;

a second photodetector pair located on the substrate with the radiation source located in the middle of the second photodetector pair, wherein the second photodetector pair and the radiation source positioned to form a second axis perpendicular to the first axis, and movement of the external object along the second axis operable to cause more photo signal to be generated in one photodetector of the second photodetector pair and less photo signal to be generated in the other photodetector of the second photodetector pair;

a second circuit electrically coupled to the second photodetector pair, the second circuit configured to produce a second output signal which correlates to movement of the external object along the second axis; and

,

a third circuit electrically coupled to the first and second photodetector pairs, the third circuit configured to detect movement of the external object along a third axis perpendicular to the first and second axes, wherein the third circuit configured to produce a third output signal which correlates to movement of the external object along the third axis.

13. The navigation input device of claim 12, wherein the navigation input device further comprises a top plate positioned above the substrate and wherein the top plate is planarly parallel to the substrate.

14. The navigation input device of claim 13, wherein the navigation input device further comprises a sensor configured to produce an output when an external object touches the top plate.

15. The navigation input device of claim 12, wherein the first and second circuits comprise differential amplifiers.

16. The navigation input device of claim 12, further comprising a reflector dome positioned above the radiation source and the first and second photodetector pairs, wherein the reflector dome is configured to reflect radiation from the radiation source to the first and second photodetector pairs and wherein the reflector dome is configured to cause more radiation to be reflected onto all, or a portion of the first or second photodetector pairs when the reflector dome is compressed by an external object.

17. The navigation input device of claim 16, wherein the metal dome made from a resilient material at least partially coated with a metallic or reflective material.

18. The navigation input device of claim 12, wherein the radiation emitted by the radiation source has a wavelength between 450 nm to 950 nm.

19. The navigation input device of claim 12, wherein the navigation input device forms a portion of a mobile device.

20. The navigation input device of claim 12, wherein the input device forms a portion of a mobile device.