Illumination structure for uniform illumination of keys

• US 9,971,084 B2
• Filed: 02/03/2016
• Issued: 05/15/2018
• Est. Priority Date: 09/28/2015
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Cao, Robert Y., Leong, Craig C., Zercoe, Bradford J., Mathew, Dinesh C., Krishnamurthi, Mahesh, Qi, Jun, Liu, Rong, Yin, Victor H.
• Primary Examiner(s): Bowman, Mary Ellen
• Application Number:
  US15/014,596
• Publication Number:
  US 20170090104A1
• Time in Patent Office: 832 Days
• CPC Class Codes: G02B 6/0038 Linear indentations or grooves, e.g. arc-shaped grooves or meandering grooves, extending over the full length or width of the light guide
• CPC Class Codes: G02B 6/0045 by shaping at least a portion of the light guide
• CPC Class Codes: G02B 6/0061 to provide homogeneous light output intensity
• CPC Class Codes: G06F 1/1662 Details related to the integrated keyboard
• CPC Class Codes: H01H 13/023 Light-emitting indicators for multi-layer switches H01H13/83
• CPC Class Codes: H01H 13/14 Operating parts, e.g. push-button
• CPC Class Codes: H01H 13/7065 characterised by the mechanism between keys and layered keyboards
• CPC Class Codes: H01H 13/83 characterised by legends, e.g. Braille, liquid crystal displays, light emitting or optical elements
• CPC Class Codes: H01H 2219/056 Diffuser; Uneven surface
• CPC Class Codes: H01H 2219/06 Reflector
• CPC Class Codes: H01H 2219/062 Light conductor
• CPC Class Codes: H01H 2219/0622 only an illuminated ring around keys

Abstract

Described is an illumination structure for a key of a keyboard. The illumination structure is used to uniformly illuminate the key and any glyphs that are present on the key. The illumination structure includes a light guide having various features that increase total internal reflection and also illuminate the glyphs of the key.

Claims

1. A key comprising:

a compressible dome;

a keycap positioned above the compressible dome;

a light emitting element; and

a light guide positioned at least partially around the compressible dome and optically coupled to the light emitting element, the light guide comprising;

a light-directing feature operative to direct light from the light emitting element around the light guide;

a set of reflection features operative to reflect the light internally around the light guide; and

a set of illumination features operative to illuminate the keycap.

2. The key of claim 1, wherein the light guide comprises a structural body.

3. The key of claim 2, wherein the structural body comprises one or more cut-out features disposed around the light guide.

4. The key of claim 2, wherein the structural body includes an interlocking feature operative to receive at least a portion of a key mechanism.

5. The key of claim 1, wherein a density of the set of reflection features increases from a first portion of the light guide to a second portion of the light guide.

6. The key of claim 1, wherein at least some of the set of illumination features are offset from a glyph of the keycap.

7. The key of claim 1, wherein the light guide has a generally circular shape.

8. The key of claim 1, wherein the light-directing feature directs a first part of the light in a first direction of travel and a second part of the light in a second direction of travel.

9. The key of claim 1, wherein:

the light guide comprises a body defining;

a top surface;

a bottom surface;

an outer sidewall attaching the top and bottom surfaces; and

an inner sidewall attaching the top and bottom surfaces and internally reflecting more light than the top surface.

10. The key of claim 9, wherein the inner sidewall comprises one or more serrations operable to reflect the light into the compressible dome.

11. An illumination structure for a key of a keyboard, comprising:

a light emitting element;

a structural body; and

a curved light guide coupled to the structural body and comprising;

a set of reflection features operative to reflect the light internally around the light guide, the set of reflection features being arranged in a first density at a first location within the light guide and arranged in a second density at a second location within the light guide; and

a set of illumination features operative to illuminate at least a portion of a keycap positioned above the illumination structure.

12. The illumination structure of claim 11, wherein the structural body comprises one or more ribs coupled to the light guide.

13. The illumination structure of claim 11, wherein the structural body comprises one or more cut-out features positioned around the light guide.

14. The illumination structure of claim 11, wherein the set of reflection features comprise one or more structures having a first set of dimensions and the set of illumination features comprises one or more structures having a second set of dimensions different from the first set of dimensions.

15. The illumination structure of claim 11, wherein the light guide comprises a set of sidewall features operative to reflect light into a center portion of the light guide.

16. The illumination structure of claim 11, wherein the light guide is symmetric about an axis.

17. The illumination structure of claim 11, wherein the light guide is asymmetric.

18. A key for a keyboard comprising:

a keycap disposed within an aperture defined by the keyboard;

a compressible dome positioned below the keycap;

a key mechanism positioned around the compressible dome and coupled to the keycap;

a structural body positioned beneath the key mechanism and formed from an optically translucent material, the structural body coupled to the key mechanism;

a light emitting element; and

a light guide optically coupled to the light emitting element and comprising;

a first internal feature operative to internally reflect light within the light guide;

a second internal feature operative to reflect light out of an inner sidewall of the light guide to illuminate a hollow interior portion of the structural body; and

a third internal feature operative to illuminate at least a portion of the keycap.

19. The key of claim 18, wherein at least a portion of the third internal feature is offset from a glyph of the keycap.

20. The key of claim 18, wherein the first internal feature comprises one or more lenticular structures.