Projector light source utilizing a solid state green light source

• US 6,212,213 B1
• Filed: 01/29/1999
• Issued: 04/03/2001
• Est. Priority Date: 01/29/1999
• Status: Expired due to Term

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Agilent Technologies, Inc.
• Inventors: Weber, Andreas G., Mueller, Gerd, Trutna, Jr., William R.
• Primary Examiner(s): Healy, Brian
• Application Number:
  US09/240,284
• Time in Patent Office: 795 Days
• Field of Search: 372/43, 372/50, 257/89, 257/93, 257/40, 257/88, 257/90, 313/503, 313/504, 313/505, 313/500, 313/501
• US Class Current: 372/50.1
• CPC Class Codes: G03B 21/2033 LED or laser light sources
• CPC Class Codes: G03B 21/204 using secondary light emission, e.g. luminescence or fluorescence using different colours G03B33/00; if related to video signals H04N9/3197
• CPC Class Codes: G03B 27/545 for enlargers
• CPC Class Codes: H04N 9/3108 by using a single electronic spatial light modulator
• CPC Class Codes: H04N 9/315 Modulator illumination systems general applications of lighting devices F21V; general optical systems G02B; lamp houses for projectors not peculiar to the presence of an electronic spatial light modulator G03B21/20

Abstract

A light source constructed from a two dimensional array of light emitting devices. The light emitting devices include first, second and third types of light emitter. The first type of light emitting device covers a first area in the two dimensional array and emits light in a first region of the optical spectrum. The second type of light emitting device covers a second area in the two dimensional array and emits light in a second region of the optical spectrum, and the third type of light emitting device covers a third area in the two dimensional array and emits light in a third region of the optical spectrum. The first, second, and third areas are chosen such that the simultaneous output from all emitters generates white light. At least one of the emitter types covers an area larger than that covered by the others. In the preferred embodiment of the present invention, the first type of light emitting device includes a light emitting device that emits light at a wavelength less than the wavelength of a green region of the optical spectrum; a color conversion compound absorbs this light and re-emits it in the green region of the optical spectrum.

Claims

1. A light source comprising a two dimensional array of light emitting devices, said light emitting devices comprising:

a first type of light emitting device covering a first area in said two dimensional array and emitting light in a first region of the optical spectrum,

a second type of light emitting device covering a second area in said two dimensional array and emitting light in a second region of the optical spectrum, and

a third type of light emitting device covering a third area in said two dimensional array and emitting light in a third region of the optical spectrum, wherein

said first, second, and third areas are chosen such that simultaneous output from all emitters generates white light, and wherein at least one of said first, second, and third areas differs from another of said first, second, and third areas.

3. The light source of claim 1 wherein one of said light emitting devices is a LED.

4. The light source of claim 1 wherein one of said light emitting devices is a laser.

2. A light source comprising a two dimensional array of light emitting devices, said light emitting devices comprising:

a first type of light emitting device covering a first area in said two dimensional array and emitting light in a first region of the optical spectrum,

a second type of light emitting device covering a second area in said two dimensional array and emitting light in a second region of the optical spectrum, and

a third type of light emitting device covering a third area in said two dimensional array and emitting light in third region of the optical spectrum, wherein

said first, second, and third areas are chosen such that simultaneous output from all emitters generates white light, and wherein at least one of said first, second, and third areas differs from another of said first, second, and third areas, and wherein said first type of light emitting device comprises a light emitting device that emits light at a wavelength less than the wavelength of a green region of the optical spectrum and a color conversion compound for absorbing said emitted light and emitting light and emitting light in said green region of the optical spectrum.