IMAGE DISPLAY APPARATUS

• US 20100238099A1
• Filed: 03/11/2010
• Published: 09/23/2010
• Est. Priority Date: 03/19/2009
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: SUMIYAMA, Fumika
• Granted Patent: US 8,425,056 B2
• Time in Patent Office: Days
• US Class Current: 345/87
• CPC Class Codes: G09G 3/001 using specific devices not provided for in groups G09G3/02 - G09G3/36, e.g. using an intermediate record carrier such as a film slide; Projection systems; Display of non-alphanumerical information, solely or in combination with alphanumerical information, e.g. digital display on projected diapositive as background slide projectors per se G03B23/00 = 42 HP
• CPC Class Codes: G09G 3/02 by tracing or scanning a light beam on a screen

Abstract

An image display apparatus includes: a light source unit which emits axially symmetric polarized light having polarization distribution symmetric with respect to the center axis of light; and a scanning unit which applies the axially symmetric polarized light to a projection surface for scanning to form an image.

Claims

1. An image display apparatus comprising:

a light source unit which emits axially symmetric polarized light having polarization distribution symmetric with respect to the center axis of light; and

a scanning unit which applies the axially symmetric polarized light to a projection surface for scanning to form an image.

2. The image display apparatus according to claim 1, wherein the light source unit includes

a laser beam source which emits a laser beam, and

a polarized light forming unit disposed on the optical path of the laser beam to convert the entering laser beam into the axially symmetric polarized light.

3. The image display apparatus according to claim 2, wherein:

the polarized light forming unit is a liquid crystal modulation element having a liquid crystal layer sandwiched between a pair of substrates; and

an orientation regulating force for orienting liquid crystal molecules of the liquid crystal layer in a concentric shape is given to the surfaces of the pair of the substrates facing the liquid crystal layer.

4. The image display apparatus according to claim 2, wherein the polarized light forming unit is an optical fiber having LP11 mode as a propagation mode.

5. The image display apparatus according to claim 2, wherein:

the polarized light forming unit is a retardation film; and

the retardation film has a first area which converts the polarization direction of the laser beam into a first direction and a second area which converts the polarization direction of the laser beam into a second direction different from the first direction within a beam spot of the applied laser beam.

6. The image display apparatus according to claim 2, wherein the polarized light forming unit includes

a branching unit which branches the laser beam into first separation light and second separation light,

a light combining unit which combines the first separation light and the second separation light into one combined light, and

a polarization element disposed at least either on the optical path of the first separation light or on the optical path of the second separation light and making the polarization directions of the first separation light the second separation light different from each other.

7. The image display apparatus according to claim 2, further comprising an expanding optical system on the optical path between the laser beam source and the polarized light forming unit.

8. The image display apparatus according to claim 1, wherein the light source unit includes

a light emission unit which emits light,

an external resonator which reflects a part of the light emitted from the light emission unit toward the light emission unit, and

a polarized light forming unit disposed on the optical path between the light emission unit and the external resonator to convert the entering light into the axially symmetric polarized light.

9. The image display apparatus according to claim 1, wherein:

the light source unit includes

a light emission unit which emits light, and

an external resonator which reflects a part of the light emitted from the light emission unit toward the light emission unit; and

the external resonator is a grating mirror which converts the entering light into the axially symmetric polarized light and reflects the converted light.

10. The image display apparatus according to claim 1, wherein:

the light source unit is provided;

a laser light source is provided to supply a laser beam having a color different from the color of the axially symmetric polarized light emitted from the light source unit;

a color combining optical system is provided to combine the axially symmetric polarized light and the laser beam having the different color; and

the axially symmetric polarized light is a color light having higher visibility than that of the laser beam having the different color.

11. The image display apparatus according to claim 1, wherein:

plural units of the light source unit are provided to supply the plural axially symmetric polarized lights having colors different from each other; and

a color combining optical system is provided to combine the plural axially symmetric polarized lights having colors different from each other.

12. The image display apparatus according to claim 2, wherein:

a plurality of laser beam sources are provided to supply plural types of laser beams having colors different from each other;

a color combining optical system is provided to combine the plural types of laser beams having colors different from each other; and

the polarized light forming unit is disposed on the optical path of the combined laser beam supplied from the color combining optical system.

13. An image display apparatus comprising:

a plurality of light source units each of which emits axially symmetric polarized light having polarization distribution symmetric with respect to the center axis of light,

wherein the light source units are disposed in two-dimensional matrix in correspondence with pixels forming an image to be displayed to form the image on a projection surface by using the axially symmetric polarized light.

14. The image display apparatus according to claim 13, wherein the light source unit includes

a laser beam source which emits a laser beam, and

a polarized light forming unit disposed on the optical path of the laser beam to convert the entering laser beam into the axially symmetric polarized light.

15. The image display apparatus according to claim 13, wherein the light source unit includes

a light emission unit which emits light,

an external resonator which reflects a part of the light emitted from the light emission unit toward the light emission unit, and

a polarized light forming unit disposed on the optical path between the light emission unit and the external resonator to convert the entering light into the axially symmetric polarized light.

16. The image display apparatus according to claim 13, wherein:

the light source unit includes

a light emission unit which emits light, and

an external resonator which reflects a part of the light emitted from the light emission unit toward the light emission unit; and

the external resonator is a grating mirror which converts the entering light into the axially symmetric polarized light and reflects the converted light.

17. The image display apparatus according to claim 13, wherein:

the light source unit is provided;

a laser light source is provided to supply a laser beam having a color different from the color of the axially symmetric polarized light emitted from the light source unit;

a color combining optical system is provided to combine the axially symmetric polarized light and the laser beam having the different color; and

the axially symmetric polarized light is a color light having higher visibility than that of the laser beam having the different color.

18. The image display apparatus according to claim 13, wherein:

plural units of the light source unit are provided to supply the plural axially symmetric polarized lights having colors different from each other; and

a color combining optical system is provided to combine the plural axially symmetric polarized lights having colors different from each other.

19. The image display apparatus according to claim 14, wherein:

a plurality of laser beam sources are provided to supply plural types of laser beams having colors different from each other;

a color combining optical system is provided to combine the plural types of laser beams having colors different from each other; and

the polarized light forming unit is disposed on the optical path of the combined laser beam supplied from the color combining optical system.