Illumination device and image display apparatus

• US 10,018,900 B2
• Filed: 02/14/2017
• Issued: 07/10/2018
• Est. Priority Date: 06/18/2010
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Kita, Koji
• Primary Examiner(s): Howard, Ryan
• Application Number:
  US15/432,054
• Publication Number:
  US 20170153537A1
• Time in Patent Office: 511 Days
• Field of Search: 353 84, 353 85, 353 94, 353122, 353 30, 353 31, 359885-892, 313483, 313501, 362 84, 362231, 2504842, 2504844
• CPC Class Codes: F21V 13/08 the elements being filters or photoluminescent elements and reflectors
• CPC Class Codes: F21V 13/14 the elements being filters or photoluminescent elements, reflectors and refractors
• CPC Class Codes: F21V 14/04 by movement of reflectors in vehicle head lamps F21S41/675
• CPC Class Codes: F21V 14/08 by movement of the screens or filters
• CPC Class Codes: F21V 5/04 of lens shape
• CPC Class Codes: F21V 7/05 plane
• CPC Class Codes: F21V 9/08 for producing coloured light, e.g. monochromatic; for reducing intensity of light with provision for controlling the colour F21V9/40
• CPC Class Codes: F21V 9/14 for producing polarised light
• CPC Class Codes: F21V 9/32 characterised by the arrangement of the photoluminescent material
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: F21Y 2115/30 Semiconductor lasers
• CPC Class Codes: G02B 26/008 in the form of devices for effecting sequential colour changes, e.g. colour wheels
• CPC Class Codes: G02B 27/283 used for beam splitting or combining
• CPC Class Codes: G03B 21/006 using LCD's
• CPC Class Codes: G03B 21/142 Adjusting of projection optics
• CPC Class Codes: G03B 21/204 using secondary light emission, e.g. luminescence or fluorescence using different colours G03B33/00; if related to video signals H04N9/3197
• CPC Class Codes: G03B 21/2073 Polarisers in the lamp house peculiar to electronic spatial light modulators H04N9/3197

Abstract

An illumination device includes: an excitation light source that emits excitation light having a first wavelength; and a fluorescent member that includes a fluorescent substance that, when it is irradiated with the excitation light, emits light having a second wavelength longer than the first wavelength, transmits a part of the excitation light and reflects another part of the excitation light, and a first reflective film provided at a side of the fluorescent substance, which is opposite to an excitation light incidence side, the fluorescent member emitting multiplexed light including an excitation light component reflected from the fluorescent substance and the first reflective film and a light component emitted from the fluorescent substance.

Claims

1. An illumination device comprising:

an excitation light source configured to emit excitation light having a spectrum with a first peak wavelength;

a rotating member comprising

a reflector, and

a fluorescent substance disposed between the reflector and excitation light source and having a continuous doughnut shape from a perspective of an excitation light propagating direction, the fluorescent substance positioned to receive the excitation light and produce an emission light having a spectrum with a second peak wavelength that is different than the first peak wavelength,

wherein the reflector is configured to reflect the emission light having the spectrum with the second peak wavelength;

a spectral optical system at an excitation light incidence side of the fluorescent substance and including a polarization beam splitter, in which the excitation light emitted from the excitation light source is incident to the spectral optical system;

a quarter wavelength plate provided between the polarization beam splitter and the fluorescent substance; and

a condensing optical system provided between the quarter wavelength plate and the fluorescent substance.

2. The illumination device of claim 1,

wherein the excitation light is incident along the continuous doughnut shape as the fluorescent substance rotates with the reflector.

3. The illumination device of claim 1,

wherein the excitation light has a spectrum with a peak wavelength within an inclusive range of 430 through 480 nm.

4. The illumination device of claim 1,

wherein the reflector has a continuous doughnut shape from the perspective of the excitation light propagating direction, and the reflector and the fluorescent substance are concentric.

5. The illumination device of claim 1, wherein the fluorescent substance is formed along a circumference of a substrate.

6. The illumination device of claim 1, wherein the spectrum with the first peak wavelength range is in at least a blue spectrum and the spectrum with the second peak wavelength range is in at least a red spectrum and a green spectrum.

7. The illumination device of claim 1, wherein the reflector includes a reflective film which reflects the excitation light and guides the excitation light to the fluorescent substance.

8. An illumination device comprising:

an excitation light source configured to emit excitation light having a first wavelength range with a first peak wavelength;

a rotating member comprising

a fluorescent portion including a fluorescent substance that when irradiated with the excitation light emits an emission light having a second wavelength range with a second peak wavelength that is different from the first peak wavelength, and

a reflective portion disposed behind the fluorescent substance that reflects the emission light emitted from the fluorescent substance,

wherein the fluorescent portion has a ring shape;

a spectral optical system at an excitation light incidence side of the fluorescent substance and including a polarization beam splitter, in which the excitation light emitted from the excitation light source is incident to the spectral optical system;

a quarter wavelength plate provided between the polarization beam splitter and the fluorescent substance; and

a condensing optical system provided between the quarter wavelength plate and the fluorescent substance.

9. The illumination device of claim 8,

wherein the first wavelength range is within an inclusive range of 430 through 480 nm.

10. The illumination device of claim 8,

wherein the fluorescent portion is formed along a circumference of a substrate.

11. The illumination device of claim 8,

wherein the first wavelength range is in at least a blue spectrum and the second wavelength range is in at least a red spectrum and a green spectrum.

12. The illumination device of claim 8, wherein the reflective portion includes a reflective film which reflects the excitation light and guides the excitation light to the fluorescent substance.

13. An illumination device comprising:

an excitation light source configured to emit excitation light having a spectrum with a first peak wavelength;

a rotating member comprising

a fluorescent substance that is positioned to receive the excitation light and when irradiated with the excitation light emits an emission light having a spectrum with a second peak wavelength that is different from the first peak wavelength, and

a reflective portion disposed behind the fluorescent substance in an excitation light propagating direction that reflects the emission light emitted from the fluorescent substance,

wherein the fluorescent substance has a continuous ring shape from a top view in the excitation light propagating direction;

a spectral optical system at an excitation light incidence side of the fluorescent substance and including a polarization beam splitter, in which the excitation light emitted from the excitation light source is incident to the spectral optical system;

a quarter wavelength plate provided between the polarization beam splitter and the fluorescent substance; and

a condensing optical system provided between the quarter wavelength plate and the fluorescent substance.

14. The illumination device of claim 13,

wherein the excitation light has a spectrum with a peak wavelength within an inclusive range of 430 through 480 nm.

15. The illumination device of claim 13,

wherein the fluorescent substance is formed along a circumference of a substrate.

16. The illumination device of claim 13, wherein the spectrum with the first peak wavelength range is in at least a blue spectrum and the spectrum with the second peak wavelength range is in at least a red spectrum and a green spectrum.

17. The illumination device of claim 13, wherein the reflective portion includes a reflective film which reflects the excitation light and guides the excitation light to the fluorescent substance.

18. An illumination device comprising:

an excitation light source configured to emit excitation light having a spectrum with a first peak wavelength;

a rotating member comprising

a fluorescent ring including a fluorescent substance that when irradiated with the excitation light emits an emission light having a spectrum with a second peak wavelength that is different from the first peak wavelength, and

a reflector disposed behind the fluorescent ring that reflects the emission light emitted from the fluorescent substance;

a spectral optical system at an excitation light incidence side of the fluorescent substance and including a polarization beam splitter, in which the excitation light emitted from the excitation light source is incident to the spectral optical system;

a quarter wavelength plate provided between the polarization beam splitter and the fluorescent substance; and

a condensing optical system provided between the quarter wavelength plate and the fluorescent substance.

19. The illumination device of claim 18,

wherein the reflector has a ring shape, and the reflector and the fluorescent ring are concentric.

20. The illumination device of claim 18,

wherein the excitation light has a spectrum with a peak wavelength within an inclusive range of 430 through 480 nm.