Illumination device and projector

• US 8,454,169 B2
• Filed: 10/04/2010
• Issued: 06/04/2013
• Est. Priority Date: 11/17/2009
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Kaseya, Hiroyasu
• Primary Examiner(s): Epps, Georgia Y
• Assistant Examiner(s): CHOWDHURY, SULTAN U.
• Application Number:
  US12/897,165
• Publication Number:
  US 20110116053A1
• Time in Patent Office: 974 Days
• Field of Search: 353/30, 353/31, 353/34, 353/48, 353/89, 353/94, 353/98, 353/99, 362/19, 362244-246, 362/268, 362/331, 362/551, 362/561, 362/800, 359/618, 359/619, 359/622, 359/623, 359/624
• US Class Current: 353/38
• CPC Class Codes: G02B 19/0028 refractive and reflective surfaces, e.g. non-imaging catadioptric systems
• CPC Class Codes: G02B 19/0057 in the form of a laser diode array, e.g. laser diode bar semiconductor laser arrays with beam combining arrangement H01S5/4012
• CPC Class Codes: G02B 19/0066 in the form of an LED array
• CPC Class Codes: G02B 27/0961 Lens arrays lens arrays per se G02B3/0006
• CPC Class Codes: G02B 27/1046 for use with transmissive spatial light modulators
• CPC Class Codes: G02B 27/123 The splitting element being a lens or a system of lenses, including arrays and surfaces with refractive power
• CPC Class Codes: G02B 27/149 using crossed beamsplitting surfaces, e.g. cross-dichroic cubes or X-cubes
• CPC Class Codes: G03B 21/20 Lamp housings
• CPC Class Codes: G03B 21/2053 Intensity control of illuminating light controlled by video signal processing H04N5/74 or H04N9/31

Abstract

An illumination device includes: a light source which emits a plurality of emission lights; a first condenser lens which stacks the plural emission lights emitted from the light source; a first fly-eye lens which divides lights stacked by the first condenser lens into a plurality of partial lights; a second fly-eye lens which converges the plural partial lights; and a second condenser lens which stacks the plural partial lights converged by the second fly-eye lens, wherein the first condenser lens stacks the plural emission lights emitted from the light source on the first fly-eye lens, and the second fly-eye lens stacks the plural partial lights on an illumination receiving area.

Claims

1. An illumination device comprising:

a light source which emits a plurality of emission lights;

a first condenser lens which stacks the plural emission lights emitted from the light source;

a first fly-eye lens which divides lights stacked by the first condenser lens into a plurality of partial lights;

a second fly-eye lens which converges the plural partial lights;

a second condenser lens which stacks the plural partial lights converged by the second fly-eye lens; and

a plurality of converging lenses provided in correspondence with the plural emission lights on an optical path between the light source and the first condenser lens to individually converge the plural emission lights emitted from the light source,

wherein

the first condenser lens stacks the plural emission lights emitted from the light source on the first fly-eye lens,

the second fly-eye lens stacks the plural partial lights on an illumination receiving area,

the plural first condenser lenses are disposed within a plane crossing the optical axes of the plural emission lights emitted from the light source, and

the plural emission lights emitted from the light source are stacked on the first fly-eye lens by each of the first condenser lenses.

2. The illumination device according to claim 1, wherein

the distance between the first condenser lens and the first fly-eye lens is longer than the focal distance of the first condenser lens;

and

the diameter of the lights stacked on the light entrance surface of the first fly-eye lens by the first condenser lens is shorter than the effective diameter of the first condenser lens.

3. The illumination device according to claim 1, wherein

the first fly-eye lens has a plurality of first element lenses disposed within a plane crossing the lights stacked by the first condenser lens at right angles;

the second fly-eye lens has a plurality of second element lenses disposed within a plane crossing the lights received from the first fly-eye lens at right angles; and

an effective diameter Sf of each of the second element lenses satisfies the following expression (1)

Sf≧

f2×

Ss/f1 

 

(1)

(Ss;

effective diameter of the first condenser lens, f1;

focal distance of the first condenser lens, f2;

focal distance of each of the first element lenses).

4. The illumination device according to claim 1, further comprising a plurality of collimating lenses provided in correspondence with the plural emission lights on an optical path between the light source and the converging lenses to individually convert the plural emission lights emitted from the light source into collimated lights.

5. The illumination device according to claim 1, further comprising a field lens disposed on an optical path between the first condenser lens and the first fly-eye lens to converge the lights stacked by the first condenser lens on the first fly-eye lens.

6. The illumination device according to claim 1, wherein the light source is a semiconductor laser, a super luminescent diode, or a light emitting diode.

7. The illumination device according to claim 1, wherein a plurality of lines and a plurality of rows of the plural emission lights are disposed.

8. A projector comprising:

the illumination device according to claim 1;

a light modulation device which modulates light received from the illumination device according to image information; and

a projection device which projects an image formed by the light modulation device.