Glass reflector for projector and manufacturing method for the same

• US 6,957,900 B2
• Filed: 11/28/2003
• Issued: 10/25/2005
• Est. Priority Date: 06/26/2003
• Status: Expired due to Fees

• Current Assignee: AGC Techno Glass Corp. (AGC, Inc.)
• Original Assignee: AGC Techno Glass Corp. (AGC, Inc.)
• Inventors: Momoi, Hiroshi, Takada, Nobuhisa, Nishio, Hiroyasu, Hirano, Naomi
• Primary Examiner(s): Husar, Stephen
• Assistant Examiner(s): Han, Jason
• Application Number:
  US10/722,412
• Publication Number:
  US 20040264200A1
• Time in Patent Office: 697 Days
• Field of Search: 362/296, 362347-350, 362/341, 359868-869, 313/113, 428/410
• US Class Current: 362/296.03
• CPC Class Codes: C03B 11/10 for making hollow or semi-hollow articles
• CPC Class Codes: C03B 23/20 Uniting glass pieces by fusing without substantial reshaping
• CPC Class Codes: C03B 23/26 Punching reheated glass
• CPC Class Codes: F21V 7/10 Construction
• CPC Class Codes: F21V 7/24 characterised by the material
• CPC Class Codes: F21V 7/28 characterised by coatings

Abstract

For example, the reflector according to the present invention is a reflector made of glass for a projector which is composed of amorphous glass whose thermal expansion coefficient is 30 to 45×10⁻⁷/° C. and includes a reflective surface for reflecting light emitted from a light source and an opening for inserting a light source bulb or a conductor to the light source bulb, in which the opening is smoothed by heat-treating the surface thereof after opening-drilling, thus mechanical damage is removed from the processed part.

Claims

1. A reflector made of glass for a projector comprising amorphous glass having a thermal expansion coefficient of 30 to 45×

10<sup>−

7</sup>/°

C. and including a reflective surface for reflecting light emitted from a light source and an opening for inserting a light source bulb or a conductor to said light source bulb, wherein said opening is smoothed by heat-treating the surface thereof after opening-drilling, thus mechanical damage is removed from a processed part.

2. A reflector made of glass for a projector according to claim 1, wherein said opening is smoothed by applying a flame by a burner.

3. A reflector made of glass for a projector according to claim 2, wherein the mean roughness of said smoothed opening is 0.03 μ

m or less.

4. A reflector made of glass for a projector according to claim 1, wherein said opening is smoothed by applying a flame by a burner and the mean roughness of said smoothed surface opening is 0.03 μ

m or less.

5. A reflector made of glass for a projector according to claim 4, wherein said reflective surface is in a shape of a rotational elliptical surface or a rotational parabolic surface and the surface accuracy in the neighborhood of said opening is less than ±

20 μ

m for an ideal curved surface.

6. A reflector made of glass for a projector according to claim 1, wherein said opening is smoothed by radiation of a laser beam.

7. A reflector made of glass for a projector according to claim 6, wherein said reflective surface is in a shape of a rotational elliptical surface or a rotational parabolic surface and the surface accuracy in the neighborhood of said opening is less than ±

20 μ

m for an ideal curved surface.

8. The reflector according to claim 1, wherein said amorphous glass is a borosilicate glass or an aluminosilicate glass.

9. The reflector according to claim 1, wherein a composition of said amorphous glass is approximately 80.9% SiO₂, 2.3% Al₂O₃, 4% Na₂O, and 12.7% B₂O₃.

10. The reflector according to claim 1, wherein a composition of said amorphous glass is approximately 78% SiO₂, 2.1% Al₂O₃, 5.2% Na₂O, and 14.5% B₂O₃.

11. The reflector according to claim 1, wherein said opening is defined as a region from an end of the opening to about 20 mm from the end of the opening in a radial direction.

12. A reflector made of glass for a projector comprising amorphous glass having a thermal expansion coefficient of 30 to 40×

10<sup>−

7</sup>/°

C. and including a reflective surface for reflecting light emitted from a light source and an opening for inserting a light source bulb or a conductor to said light source bulb, wherein said opening is smoothed by applying a flame to the surface thereof by a burner after opening-drilling and the mean roughness of said smoothed surface is 0.03 μ

m or less.

13. A reflector made of glass for a projector according to claim 12, wherein said reflective surface is in a shape of a rotational elliptical surface or a rotational parabolic surface and the surface accuracy in the neighborhood of said opening is less than ±

20 μ

m for an ideal curved surface.

14. A glass reflector with heat-resistance for a projector, comprising:

a curved reflective surface portion for reflecting light emitted from a light source bulb; and

an opening portion drilled through the curved reflective surface portion to insert the light source bulb or a conductor to the light source bulb, wherein the glass reflector is made of amorphous glass with thermal expansion coefficient of 30 to 45×

10<sup>−

7</sup>/°

C., and the opening portion has a fire-polished surface with a mean roughness of 0.03 μ

m or less without mechanical damage.

15. A glass reflector with heat-resistance for a projector according to claim 14, wherein an operating temperature of the curved reflective surface portion and the opening portion is approximately 450°

C.