IP Library Granted Patent US 9,500,935
Granted Patent B2
US 9,500,935 · App. 14/112,528 · Granted Nov 22, 2016

Projection image display device

Inventors: Hiroko Chifu (Tokyo, JP); Motoyasu Utsunomiya (Tokyo, JP)
Assignee: NEC Display Solutions, Ltd.
G03B21/142G02B26/008G02B27/102G02B27/48G03B21/204G03B21/208H04N9/3144H04N9/3161G02B2207/113
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Quick Facts
Patent No.
US 9,500,935
App. No.
14/112,528
Granted
Nov 22, 2016
Kind
B2
Abstract

A projection image display device includes: a laser light source; phosphor excited by excitation laser light emitted from laser light source to emit light; an optical functional reflector (cross dichroic prism) into which at least one laser light from laser light source and fluorescent light from phosphor enters and which reflects light of a specific wavelength band while transmitting light of the other wavelength band; a diffusion plate that diffuses the laser light; a diffusion plate driver for moving the diffusion plate; and a spatial light modulation element (digital micromirror device) that modulates the light output from cross dichroic prism. Diffusion plate is disposed on the optical path of excitation laser light applied from laser light source to phosphor.

Claims (54)

1. A projection image display device comprising:

a laser light source;

a phosphor excited by excitation laser light emitted from at least one laser light source to emit light;

a reflector into which at least one of laser light from the laser light sources and fluorescent light from the phosphor enters and which reflects light of a specific wavelength band while transmitting light of the other wavelength band;

a plurality of diffusion plates that diffuse the laser light;

at least one diffusion plate driver which moves the diffusion plates; and

a spatial light modulation element that modulates the light output from the reflector,

the diffusion plates being disposed on an optical path of the excitation laser light applied from the laser light source to the phosphor, wherein

the excitation laser light applied to the phosphor from at least one of the laser light sources and light source laser light from the laser light source other than said laser light source pass through different optical paths before entering the reflector; and

the diffusion plates are respectively arranged on the optical path of the excitation laser light before entering the reflector and on the optical path of the light source laser light before entering the reflector.

2. The projection image display device according to claim 1 , further comprising: a circular substrate coated or mixed with the phosphor to be excited by the excitation laser light to emit fluorescent light of a desired color; and a wheel motor for driving the circular substrate to rotate.

3. The projection image display device according to claim 1 , further comprising:

a circular substrate coated or mixed with the phosphor to be excited by the excitation laser light to emit fluorescent light of a desired color;

a wheel motor for driving the circular substrate to rotate; and

a leaf spring for holding at least one of the diffusion plates,

wherein the at least one diffusion plate driver comprises the wheel motor, and a solid propagation frequency of the wheel motor matches a natural frequency of the leaf spring.

4. The projection image display device according to claim 1 , further comprising a leaf spring for holding at least one of the diffusion plates,

wherein the at least one diffusion plate driver comprises a vibration motor, and a solid propagation frequency of the vibration motor matches a natural frequency of the leaf spring.

5. The projection image display device according to claim 1 , further comprising a leaf spring for holding at least one of the diffusion plates,

wherein the diffusion plate driver comprises a cooling fan, and a solid propagation frequency of the cooling fan matches a natural frequency of the leaf spring.

6. The projection image display device according to claim 1 , wherein:

the diffusion plates are respectively arranged on the optical path of the excitation laser light applied to the phosphor from at least one of the laser light sources before entering the reflector and on the optical path of the light source laser light from the laser light source other than said laser light source before entering the reflector;

the plurality of diffusion plates are respectively connected to different leaf springs; and

each leaf spring is connected to the diffusion plate driver.

7. The projection image display device according to claim 6 , wherein a solid propagation frequency of the diffusion plate driver matches a natural frequency of at least one of the leaf springs for holding the plurality of diffusion plates.

8. The projection image display device according to claim 1 , further comprising a light integrator located between the reflector and the spatial light modulation element and configured to form light that passed through the reflector into a rectangular light flux of a uniform illuminance distribution,

wherein the light integrator comprises a light tunnel.

9. The projection image display device according to claim 1 , wherein the reflector comprises a cross dichroic prism.

10. The projection image display device according to claim 1 , wherein the spatial light modulation element comprises a digital micromirror device.

11. A projection image display device, comprising:

a plurality of laser light sources;

a phosphor excited by excitation laser light emitted from at least one laser light source to emit light;

a reflector into which at least one of laser light from the laser light sources and fluorescent light from the phosphor enters and which reflects light of a specific wavelength band while transmitting light of the other wavelength band;

a plurality of diffusion plates that diffuse the laser light;

at least one diffusion plate driver which moves the diffusion plates; and

a spatial light modulation element that modulates the light output from the reflector,

the diffusion plates being disposed on an optical path of the excitation laser light applied from the laser light source to the phosphor, wherein:

the excitation laser light applied to the phosphor from at least one of the laser light sources, and light source laser light from the laser light source other than said laser light source are synthesized on an optical path before entering the reflector; and

the diffusion plates are arranged on the optical path of the excitation laser light and the light source laser light that have been synthesized,

the diffusion plates are respectively arranged on the optical path of the excitation laser light applied to the phosphor from at least one of the laser light sources before entering the reflector and on the optical path of the light source laser light from the laser light source other than said laser light source before entering the reflector;

the plurality of diffusion plates are respectively connected to different leaf springs; and

each leaf spring is connected to the at least one diffusion plate driver.

12. The projection image display device according to claim 1 , wherein:

the diffusion plates are respectively arranged on the optical path of the excitation laser light applied to the phosphor from at least one of the laser light sources before entering the reflector and on the optical path of the light source laser light from the laser light source other than said laser light source before entering the reflector;

the plurality of diffusion plates are respectively connected to different leaf springs; and

each leaf spring is connected to the at least one diffusion plate driver.

13. The projection image display device according to claim 11 , wherein a solid propagation frequency of the at least one diffusion plate driver matches a natural frequency of at least one of the leaf springs for holding the plurality of diffusion plates.

14. The projection image display device according to claim 12 , wherein a solid propagation frequency of the at least one diffusion plate driver matches a natural frequency of at least one of the leaf springs for holding the plurality of diffusion plates.

15. A method for displaying an image, comprising:

applying excitation laser light to a phosphor from a laser light source through a diffusion plate which diffuses laser light and which is driven by a diffusion plate driver;

causing at least one of laser light from the laser light source and fluorescent light from the phosphor to enter into a reflector which reflects light of a specific wavelength band while transmitting light of the other wavelength band;

modulating the light output from the reflector; and

projecting the modulated light, wherein

the diffusion plate is held by a leaf spring, and the diffusion plate driver has a solid propagation frequency which matches a natural frequency of the leaf spring.

Assignments (2)
CHANGE OF NAME Recorded Feb 8, 2021
From: NEC DISPLAY SOLUTIONS, LTD.
To: SHARP NEC DISPLAY SOLUTIONS, LTD.
Reel/Frame 055256/0755 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 21, 2013
From: CHIFU, HIROKO; UTSUNOMIYA, MOTOYASU
To: NEC DISPLAY SOLUTIONS, LTD.
Reel/Frame 031505/0819 →
Continuity (1)
Related Publication 20140043589A1 · Feb 13, 2014