Projection display device

• US 8,651,671 B2
• Filed: 04/12/2010
• Issued: 02/18/2014
• Est. Priority Date: 04/23/2009
• Status: Active Grant

• Current Assignee: OM Digital Solutions Corporation
• Original Assignee: Olympus Corporation
• Inventors: Miyazaki, Kanto, Murayama, Kazuaki
• Primary Examiner(s): Legasse, Jr., Francis M
• Assistant Examiner(s): BROOKS, JERRY L.
• Application Number:
  US12/798,875
• Publication Number:
  US 20100271599A1
• Time in Patent Office: 1,408 Days
• Field of Search: 353/98, 362/259, 359/599, 359707-718, 359/722, 359/723
• US Class Current: 353/98
• CPC Class Codes: G02B 27/0933 Systems for active beam shaping by rapid movement of an element
• CPC Class Codes: G02B 27/1033 having a single light modulator for all colour channels
• CPC Class Codes: G02B 27/1053 having a single light modulator for all colour channels
• CPC Class Codes: G02B 27/48 Laser speckle optics
• CPC Class Codes: G02B 5/0278 used in transmission
• CPC Class Codes: G03B 21/14 Details
• CPC Class Codes: G03B 21/2033 LED or laser light sources
• CPC Class Codes: G03B 21/208 Homogenising, shaping of the illumination light

Abstract

A projection display device which displays an image by projecting the image on a screen includes a laser light source 1 (1a, 1b, 1c) for emitting coherent light, a display device 3 for forming an image to be displayed on a screen 5 in an area illuminated by a luminous flux from the laser light source 1, a first diffusion plate 14 for diffusing a luminous flux, and a second diffusion plate 15 for diffusing a luminous flux. The first diffusion plate 14 is provided in at least one of a conjugate position of the laser light source 1 or the vicinity of the conjugate position in the optical path of the optical system including the laser light source 1 through the screen 5. The second diffusion plate 15 is provided in at least one of a conjugate position of the display device 3 or the vicinity of the conjugate position. At least one of the first diffusion plate 14 and the second diffusion plate 15 fluctuates perpendicularly to an optical axis.

Claims

1. A projection display device which displays an image by projecting the image on a screen, comprising:

at least one light source outputting coherent light;

a display device forming an image to be displayed on the screen in an area illuminated by a luminous flux from the light source;

a first diffusion unit diffusing the luminous flux;

a second diffusion unit diffusing the luminous flux; and

a luminous flux intensity leveling unit leveling intensity of the luminous flux;

wherein;

the first diffusion unit is provided in a light source conjugate position in an optical path of an optical system including the light source through the screen;

the second diffusion unit is provided in at least one of a display device conjugate position and a vicinity of the position in the optical path of the optical system;

at least one of the first diffusion unit and the second diffusion unit fluctuates perpendicularly to an optical axis;

the optical system including the light source through the screen comprises;

an optical system for illumination propagating the luminous flux emitted from the light source into a predetermined optical path and leading the luminous flux toward the screen; and

an optical system for projection scaling up and projecting, onto the screen, the image formed in the illuminated area of the display device,

wherein the display device forms an image to be displayed on the screen in the area illuminated by the luminous flux led by the optical system for illumination;

the first diffusion unit is provided in the light source conjugate position in the optical path of the optical system for illumination;

the second diffusion unit is provided in at least one of the display device conjugate position and the vicinity of the conjugate position in the optical path of the optical system for illumination;

the luminous flux intensity leveling unit is provided in the optical system for illumination, a luminous flux incident surface of the luminous flux intensity leveling unit has a conjugate relationship with the light source, a luminous flux emission surface of the luminous flux intensity leveling unit has a conjugate relationship with the display device;

the first diffusion unit is provided in a position of the luminous flux incident surface or a vicinity of the position; and

the second diffusion unit is provided in a position of the luminous flux emission surface or a vicinity of the position.

2. The device according to claim 1, wherein at least one of the first diffusion unit and the second diffusion unit is an optical diffusion device capable of arbitrarily forming a diffusion angle and a luminous intensity distribution form acquired when a luminous flux is transmitted.

3. The device according to claim 2, wherein the diffusion angle of the optical diffusion device is 10°

through 40°

.

4. The device according to claim 1, further comprising a fluctuating unit perpendicularly fluctuating at least one of the first diffusion unit and the second diffusion unit to an optical axis.

5. The device according to claim 4, wherein the fluctuating unit comprises a piezoelectric element.

6. The device according to claim 1, wherein a fluctuation speed when at least one of the first diffusion unit and the second diffusion unit fluctuates perpendicularly to an optical axis is 2.0 mm/s or more.

7. The device according to claim 1, wherein the display device reflects a luminous flux and forms an image.

8. The device according to claim 1, wherein the display device transmits a luminous flux and forms an image.

9. The device according to claim 1, wherein the luminous flux intensity leveling unit, the first diffusion unit and the second diffusion unit are configured in a unitary construction.

10. The device according to claim 1, wherein the luminous flux intensity leveling unit is a rod integrator.