Projection type image display apparatus and projection optical system

• US 8,210,693 B2
• Filed: 03/18/2010
• Issued: 07/03/2012
• Est. Priority Date: 03/31/2009
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Nishikawa, Jun
• Primary Examiner(s): Epps, Georgia Y
• Assistant Examiner(s): CHOWDHURY, SULTAN U.
• Application Number:
  US12/661,500
• Publication Number:
  US 20100245784A1
• Time in Patent Office: 838 Days
• Field of Search: 353/30, 353/31, 353/34, 353/38, 353/69, 353/70, 353/77, 353/78, 353/98, 353/99, 353/122, 359/364, 359726-736, 359/858, 359/859, 348/783
• US Class Current: 353/99
• CPC Class Codes: G02B 13/16 for use in conjunction with image converters or intensifiers , or for use with projectors, e.g. objectives for projection TV
• CPC Class Codes: G02B 17/08 Catadioptric systems used in non-imaging applications G02B19/00
• CPC Class Codes: G03B 21/28 Reflectors in projection beam in illumination beam G03B21/2066

Abstract

A projection type image display apparatus includes: a light source; an illumination optical system that uniformly illuminates beams, which are emitted from the light source, on a surface of an image modulation element as a primary image plane; and a projection optical system that projects image information of the primary image plane modulated by the image modulation element on a screen as a secondary image plane in an enlarged manner. The projection optical system includes a first optical system having a positive refractive power and including a plurality of transmissive surfaces, and a second optical system having a positive refractive power and including a concave reflective surface. The first optical system has a first reflective surface disposed between any surfaces of the plurality of transmissive surfaces, and a second reflective surface disposed between the first optical system and second optical system.

Claims

1. A projection type image display apparatus comprising:

a light source;

an illumination optical system that uniformly illuminates beams, which are emitted from the light source, on a surface of an image modulation element as a primary image plane; and

a projection optical system that projects image information of the primary image plane modulated by the image modulation element on a screen as a secondary image plane in an enlarged manner,

wherein the projection optical system includes

a first optical system that has a positive refractive power and includes a plurality of transmissive surfaces, and

a second optical system that has a positive refractive power and includes a concave reflective surface,

wherein the first optical system has

a first reflective surface disposed between any surfaces of the plurality of transmissive surfaces, and

a second reflective surface disposed between the first optical system and second optical system, and

wherein assuming that an optical axis is a z axis, a y-axis rotation angle of the first reflective surface is β

1, and a y-axis rotation angle of the second reflective surface is β

2, the following conditional expressions are satisfied

20°

<

|β

1|<

45°

 

 

(1)

20°

<

|β

2|<

45°

 

 

(2).

2. The projection type image display apparatus according to claim 1, wherein assuming that an x-axis rotation angle of the first reflective surface is α

1 and an x-axis rotation angle of the second reflective surface is α

2, the following conditional expressions are satisfied

3°

<

|α

1|<

20°

 

 

(3)

3°

<

|α

2|<

20°

 

 

(4).

3. The projection type image display apparatus according to claim 1, wherein the following conditional expressions are satisfied

−

10°

<

α

1+α

2<

10°

 

 

(5)

−

10°

<

β

1+β

2<

10°

 

 

(6).

5. The projection type image display apparatus according to claim 1, wherein all the first and second reflective surfaces are flat reflective surfaces.

4. A projection type image display apparatus comprising:

a light source;

an illumination optical system that uniformly illuminates beams, which are emitted from the light source, on a surface of an image modulation element as a primary image plane; and

a projection optical system that projects image information of the primary image plane modulated by the image modulation element on a screen as a secondary image plane in an enlarged manner,

wherein the projection optical system includes

a first optical system that has a positive refractive power and includes a plurality of transmissive surfaces, and

a second optical system that has a positive refractive power and includes a concave reflective surface,

wherein the first optical system has

a first reflective surface disposed between any surfaces of the plurality of transmissive surfaces, and

a second reflective surface disposed between the first optical system and second optical system, and

wherein assuming that an optical axis is a z axis, a y-axis rotation angle of the first reflective surface is β

1, a y-axis rotation angle of the second reflective surface is β

2, an x-axis rotation angle of the first reflective surface is α

1, and an x-axis rotation angle of the second reflective surface is α

2, the following conditional expressions are satisfied

20°

<

|β

1|<

45°

 

 

(1)

20°

<

|β

2|<

45°

 

 

(2)

3°

<

|α

1|<

20°

 

 

(3)

3°

<

|α

2|<

20°

 

 

(4)

−

10°

<

α

1+α

2<

10°

 

 

(5)

−

10°

<

β

1+β

2<

10°

 

 

(6).

6. A projection optical system comprising:

a first optical system that has a positive refractive power and includes a plurality of transmissive surfaces, and

a second optical system that has a positive refractive power and includes a concave reflective surface,

wherein the projection optical system is configured to project an image in an enlarged manner from a primary image plane on a reduction side to a secondary image plane on a magnification side,

wherein the first optical system has

a first reflective surface disposed between any surfaces of the plurality of transmissive surfaces, and

a second reflective surface disposed between the first optical system and second optical system, and

wherein assuming that an optical axis is a z axis, a y-axis rotation angle of the first reflective surface is β

1, a y-axis rotation angle of the second reflective surface is β

2, an x-axis rotation angle of the first reflective surface is α

1, and an x-axis rotation angle of the second reflective surface is α

2, the following conditional expressions are satisfied

20°

<

|β

1|<

45°

 

 

(1)

20°

<

|β

2|<

45°

 

 

(2)

3°

<

|α

1|<

20°

 

 

(3)

3°

<

|α

2|<

20°

 

 

(4)

−

10°

<

α

1+α

2<

10°

 

 

(5)

−

10°

<

β

1+β

2<

10°

 

 

(6).