Keypad lighting using polymer light emitting devices

• US 7,612,306 B2
• Filed: 03/25/2008
• Issued: 11/03/2009
• Est. Priority Date: 02/20/2003
• Status: Active Grant

• Current Assignee: Sony Ericsson Mobile Communications (Sony Group Corp.)
• Original Assignee: Sony Ericsson Mobile Communications USA Incorporated (Sony Group Corp.)
• Inventors: Larsson, Mats, Klinghult, Gunnar
• Primary Examiner(s): Friedhofer; Michael A
• Application Number:
  US12/054,759
• Publication Number:
  US 20080173526A1
• Time in Patent Office: 588 Days
• Field of Search: 200/5.A, 200310-317, 341/20, 341/22, 341/35, 345/156, 345168-170, 345/184
• US Class Current: 200/314
• CPC Class Codes: H01H 13/70 having a plurality of operating members associated with different sets of contacts, e.g. keyboard mounting together a plurality of independent switches H02B
• CPC Class Codes: H01H 2219/037 using organic materials, e.g. organic LED
• CPC Class Codes: H04M 1/22 Illumination; Arrangements for improving the visibility of characters on dials

Abstract

At least one key of a keypad of an electronic device, such as a wireless terminal, includes a polymer light emitting device, also referred to as a polymer LED, thereon. A polymer LED may be on the inner and/or outer surface of the face of the key and may be unpatterned and/or patterned to form a symbol.

Claims

1. A wireless terminal comprising:

a housing;

a plurality of electronic components in the housing that are configured to transmit and/or receive wireless communications;

a keypad at least partially in the housing, comprising at least one key that comprises;

at least one wall including first and second opposing ends;

a face that extends from the first end and including an outer surface facing away from the second end that is configured for user activation and an inner surface opposite the outer surface and facing toward the second end; and

a polymer light emitting layer on the outer surface, opposite the inner surface.

2. A wireless terminal according to claim 1 wherein the polymer light emitting layer is patterned to form a symbol.

3. A keypad for an electronic device comprising:

at least one key including a face; and

a polymer light emitting layer on the at least one key that is conformal to the face;

wherein the at least one key comprises a first key and a second key, wherein the polymer light emitting layer on the first key is configured to emit light of a first color and wherein the polymer light emitting layer on the second key is configured to emit light of a second color that is different from the first color.

4. A keypad according to claim 3 wherein the at least one key comprises:

a face including an outer surface that is configured for user activation and an inner surface opposite the outer surface;

wherein the polymer light emitting layer is on the inner surface, opposite the outer surface.

5. A keypad according to claim 4 wherein the at least one key includes at least one wall that extends from the inner surface and wherein the wireless terminal further comprises first and second electrodes that are electrically connected to the polymer light emitting layer and extend along the at least one wall.

6. A keypad according to claim 3 wherein the at least one key comprises:

a face including an outer surface that is configured for user activation and an inner surface opposite the outer surface;

wherein the polymer light emitting layer is on the outer surface, opposite the inner surface.

7. A keypad according to claim 6 further comprising a coating on the polymer light emitting layer opposite the outer surface.

8. A keypad according to claim 3 wherein the polymer light emitting layer is an unpatterned polymer light emitting layer.

9. A keypad according to claim 8 wherein the at least one key comprises:

a face including an outer surface that is configured for user activation and an inner surface opposite the outer surface;

wherein at least one of the outer surface and the inner surface is patterned to form a symbol.

10. A keypad according to claim 8 wherein the at least one key comprises:

a face including an outer surface that is configured for user activation and an inner surface opposite the outer surface;

wherein at least one of the outer surface and the inner surface includes a patterned layer thereon which forms the symbol.

11. A keypad according to claim 3 wherein the polymer light emitting layer is patterned to form a symbol.

12. A key for an electronic device comprising:

at least one wall including first and second opposing ends;

a face that extends from the first end and including an outer surface facing away from the second end that is configured for user activation and an inner surface opposite the outer surface and facing toward the second end; and

a polymer light emitting layer on the outer surface opposite the inner surface and that is conformal to the face.

13. A key according to claim 12 wherein the polymer light emitting layer is an unpatterned polymer light emitting layer.

14. A key according to claim 13 wherein at least one of the outer surface and the inner surface is patterned to form a symbol.

15. A key according to claim 14 wherein at least one of the outer surface and the inner surface includes an opening therein which forms the symbol.

16. A key according to claim 13 wherein at least one of the outer surface and the inner surface includes a patterned layer thereon which forms the symbol.

17. A key according to claim 12 wherein the polymer light emitting layer is patterned to form a symbol.

18. A key according to claim 12 further comprising a coating on the polymer light emitting layer opposite the outer surface.

19. A key according to claim 12 further comprising:

first and second electrodes that are electrically connected to the polymer light emitting layer and extend along the at least one wall.

20. A key according to claim 12 wherein the polymer light emitting layer is configured to emit light of a first color and to emit light of a second color that is different from the first color.