Image display apparatus including a controller that controls a light amount regulating film based on an amount of extraneous light received by a light receiving element

• US 7,922,373 B2
• Filed: 11/14/2008
• Issued: 04/12/2011
• Est. Priority Date: 11/16/2007
• Status: Expired due to Fees

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Kadowaki, Shinichi, Mizushima, Tetsuro, Yamamoto, Kazuhisa
• Primary Examiner(s): Cariaso; Alan
• Application Number:
  US12/271,155
• Publication Number:
  US 20090141496A1
• Time in Patent Office: 879 Days
• Field of Search: 362/482, 362/84, 362/259, 362/293, 362/260, 362/503, 362/511, 349/11, 405/42, 405/43
• US Class Current: 362/489
• CPC Class Codes: B60K 2360/334 Projection means
• CPC Class Codes: G02B 2027/0118 comprising devices for improving the contrast of the display / brillance control visibility
• CPC Class Codes: G02B 2027/014 comprising information/image processing systems
• CPC Class Codes: G02B 26/123 Multibeam scanners, e.g. using multiple light sources or beam splitters
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence

Abstract

An image display apparatus includes a laser source for emitting ultraviolet or blue display-use laser light having a wavelength of 420 nm or less; and a display unit including a fluorescent light generating section for generating fluorescent light when irradiated with the display-use laser light, wherein the display unit displays an image using the fluorescent light generated by the fluorescent light generating section, wherein the display unit further includes an extraneous light shielding section for shielding an extraneous light which is emitted from a back side of the display unit and which has a wavelength in a range where the fluorescent light is generated so as to prevent the extraneous light from entering in the fluorescent light generating section.

Claims

1. An image display apparatus comprising:

a laser source for emitting ultraviolet or blue display-use laser light having a wavelength of 420 nm or less;

a display unit including a fluorescent light generating section for generating fluorescent light when irradiated with the display-use laser light, wherein said display unit displays an image using the fluorescent light generated by said fluorescent light generating section,

a controller for controlling a light amount regulating film; and

a light receiving element provided on a back side of said fluorescent light generating section;

wherein said display unit further includes an extraneous light shielding section for shielding an extraneous light which is emitted from a back side of said display unit and which has a wavelength in a range where the fluorescent light is generated so as to prevent said extraneous light from entering in said fluorescent light generating section, and said light amount regulating film formed on the back side of said fluorescent light generating section for adjusting the amount of the extraneous light which reaches said fluorescent light generating section; and

said controller controls said light amount regulating film based on the amount of the extraneous light received by said light receiving element, thereby adjusting the amount of the extraneous light to be transmitted through said light amount regulating film.

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

said extraneous light shielding section includes a transparent plate formed on the back side of said fluorescent light generating section, said transparent plate containing a material which blocks the extraneous light which has the wavelength in a range where the fluorescent light is generated.

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

said extraneous light shielding section includes an extraneous light filtering film formed on the back side of said fluorescent light generating section, said extraneous light filtering film containing a material which blocks the extraneous light which has the wavelength in a range where the fluorescent light is generated.

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

said display unit further includes an antireflective film formed so as to cover at least an inside surface of said fluorescent light generating section.

5. The image display apparatus according to claim 4, wherein:

said antireflective film contains a material having a photocatalytic effect.

6. The image display apparatus according to claim 4, wherein:

said antireflective film has a single-layered or multi-layered structure.

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

said laser source focuses the display-use laser light focuses within said fluorescent light generating section.

8. The image display apparatus according to claim 1 further comprising:

a scanning section for scanning the display-use laser light over said display unit,

wherein said fluorescent light generating section generates the fluorescent light for use in displaying the image by scanning the display-use laser light over said fluorescent light generating section by said scanning section.

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

said laser source includes a semiconductor laser device having a plurality of striped active regions.

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

the fluorescent light is green light.

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

said laser source includes a semiconductor laser device which emits laser light components in at least three wavelength ranges having different central wavelengths so that said fluorescent light generating section generates red, green and blue components of the fluorescent light when irradiated with the display-use laser light.

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

a transparent plate formed on the back side of said fluorescent light generating section constitutes part of a windshield of a vehicle, said image display apparatus further comprising;

a scanning section for scanning the display-use laser light over said display unit; and

an optical fiber for guiding the display-use laser light emitted from said laser source to said scanning section.

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

said laser source is provided under a dash panel or a seat of the vehicle.

14. The image display apparatus according to claim 12, further comprising:

a display-use laser light shielding section for preventing the display-use laser light scanned by said scanning section from entering a visual space of a vehicle occupant.

15. The image display apparatus according to claim 12 wherein said controller controls said image display apparatus to cut off power supply to said laser source under conditions where a seat belt for a vehicle occupant is not locked to a specific position.