OPTICAL JOG WHEEL WITH SPIRAL CODING ELEMENT

• US 20080099669A1
• Filed: 08/21/2007
• Published: 05/01/2008
• Est. Priority Date: 11/01/2006
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Avago Technologies ECBU IP Singapore Pte Limited (Broadcom, Inc.)
• Inventors: Orsley, Timothy James, Wong, Weng Fei, Lum, Chee Foo, Foo, Siang Leong
• Granted Patent: US 7,675,026 B2
• Time in Patent Office: Days
• US Class Current: 250/230
• CPC Class Codes: G01D 5/3473 Circular or rotary encoders

Abstract

A user navigational apparatus. The user navigational apparatus includes a dial, a coding element, and an encoder. The coding element is coupled to a dial. The coding element includes a track of alternating reflective and non-reflective sections, each having a substantially oblique leading edge relative to a direction of movement of the coding element. The encoder includes an emitter and a detector. The emitter generates a light signal incident on the track of the coding element. The detector detects a reflected light signal which corresponds to a portion of the incident light signal that is reflected off of the reflective sections of the track. The detector also generates a channel signal corresponding to the reflected light signal.

Claims

1. A user navigational apparatus comprising:

a dial;

a coding element coupled to the dial, the coding element comprising a track of alternating reflective and non-reflective sections, wherein each of the reflective and non-reflective sections comprises a substantially oblique leading edge relative to a direction of movement of the coding element; and

an encoder comprising an emitter and a detector, the emitter configured to generate a light signal incident on the track of the coding element, the detector configured to detect a reflected light signal reflected off of the reflective sections of the track and to generate a channel signal corresponding to the reflected light signal.

2. The user navigational apparatus of claim 1 further comprising:

a decoder coupled to the encoder, the decoder to generate a count signal corresponding to the channel signal; and

a microprocessor coupled to the decoder, the microprocessor to implement a user navigational operation on a controlled device in response to a movement of the dial by a user.

3. The user navigational apparatus of claim 2 wherein the user navigational operation comprises a scrolling operation corresponding to rotation of the dial, a first button click operation corresponding to a depression of the dial, or a second button click operation corresponding to a depression of an independent button.

4. The user navigational apparatus of claim 3 wherein at least one of the first and second button click operations corresponds to a directional selection or an item selection.

5. The user navigational apparatus of claim 3 further comprising:

a switch coupled to the dial, the switch configured to generate a switch signal in response to depression of the dial at approximately a location of the switch;

a dome switch operationally coupled to the independent button; and

an illumination ring approximately surrounding the independent button, wherein the dial circumscribes the illumination ring and the independent button.

6. The user navigational apparatus of claim 5 further comprising:

a back plate;

a circuit substrate coupled to the back plate, wherein the encoder is coupled to the circuit substrate; and

a mounting bracket coupled to the back plate, wherein the coding element, the dial, the independent button, and the illumination ring are mounted to the mounting bracket.

7. The user navigational apparatus of claim 1 wherein the detector comprises:

a photodiode to detect the reflected light signal reflected off of the reflective sections of the track; and

signal processing circuitry coupled to the photodiode, the signal processing circuitry to generate the channel signal corresponding to the reflected light signal.

8. The user navigational apparatus of claim 7 further comprising an air gap between the coding element and the emitter and between the coding element and the detector, wherein the emitter and the detector are not encapsulated by an encapsulant.

9. The user navigational apparatus of claim 7 further comprising an encapsulant to jointly encapsulate the emitter and the detector.

10. The user navigational apparatus of claim 7 further comprising:

a first encapsulant to encapsulate the emitter; and

a second encapsulant to encapsulate the detector.

11. The user navigational apparatus of claim 7 further comprising:

a first encapsulant to encapsulate the emitter; and

a second encapsulant to encapsulate a wire bond of the detector, wherein the second encapsulant does not encapsulate the photodiode.

12. The user navigational apparatus of claim 1 wherein the encoder comprises an incremental, multi-turn, multi-channel, rotary encoder.

13. The user navigational apparatus of claim 1 wherein the encoder comprises a chip-on-board emitter and detector or a discrete transfer molded emitter-detector package.

14. A user navigational apparatus comprising:

a rotary dial;

means for generating a light signal incident on a coded track;

means for generating a spiral-shaped light image in response to the light signal incident on the coded track; and

means for detecting motion of the coded track, wherein the coded track is configured to move in response to a first user movement of the rotary dial.

15. The user navigational apparatus of claim 14 further comprising:

means for implementing a user navigational operation on a controlled device in response to the first user movement of the rotary dial; and

means for activating a switch in response to a second user movement of the rotary dial.

16. The user navigational apparatus of claim 14 further comprising means for encapsulating at least a portion of an encoder mounted in conjunction with the coded track.

17. The user navigational apparatus of claim 14 further comprising means for detecting the spiral-shaped light image.

18. A method for making a user navigational apparatus, the method comprising:

coupling a code wheel to a rotary dial, wherein the code wheel comprises a track of alternating reflective and non-reflective sections, wherein each of the reflective and non-reflective sections comprises a substantially oblique leading edge relative to a direction of movement of the code wheel;

mounting an emitter on a circuit substrate relative to the code wheel, the emitter to generate a light signal incident on the track of the code wheel; and

mounting a detector on the circuit substrate relative to the code wheel, the detector to detect a reflected spiral-shaped light signal reflected off of the reflective sections of the track and to generate a channel signal corresponding to the reflected light signal.

19. The method of claim 18 further comprising:

coupling the detector to a decoder to generate a count signal corresponding to the channel signal; and

coupling the decoder to a microprocessor to implement a user navigational operation on a controlled device in response to a movement of the rotary dial by a user.

20. The method of claim 18 further comprising mounting a switch on the circuit substrate at a location aligned with a portion of the rotary dial, wherein the switch is configured to generate a switch signal in response to depression of the portion of the rotary dial.