Mirror with dichroic coating lamp housing

• US 5,177,396 A
• Filed: 12/19/1990
• Issued: 01/05/1993
• Est. Priority Date: 12/19/1990
• Status: Expired due to Fees

• Current Assignee: GTE Products Corporation (Ams-Osram AG)
• Original Assignee: GTE Products Corporation (Ams-Osram AG), GTE Sylvania Incorporated (Ams-Osram AG)
• Inventors: Hoeben, Louis L. J. M., Gielen, Joseph G. M. G., Mellor, Charles E.
• Primary Examiner(s): Yusko, Donald J.
• Assistant Examiner(s): Patel, Ashok
• Application Number:
  US07/630,148
• Time in Patent Office: 748 Days
• Field of Search: 313/113, 313/112, 313/25, 313/579, 313/580, 313/635, 313/638, 312/341, 312/296, 312/293, 312/310, 312/311, 359/360, 359/589, 359/359, 359/584, 359/585, 359/586, 359/588, 359/838, 359/839, 359/884
• US Class Current: 313/113
• CPC Class Codes: F21V 7/24 characterised by the material
• CPC Class Codes: F21V 7/28 characterised by coatings
• CPC Class Codes: G02B 5/0833 comprising inorganic materials only
• CPC Class Codes: G02B 5/0858 the reflecting layers comprising a single metallic layer with one or more dielectric layers

Abstract

A light mirror and a lamp including a light mirror are disclosed. The light mirror includes a light pervious substrate having a reflecting surface, a metal coating disposed in the reflecting surface, and a dichroic coating disposed on the metal coating. The dichroic coating is designed to reflect essentially all of the visible light spectrum and to transmit infra-red radiation and any unreflected portion of the visible light spectrum. A method for controlling the heat transmission of a cold light mirror is also disclosed.

Claims

1. A lamp comprising:

a light mirror having a reflector-shaped light pervious substrate partially enclosing an interior and having a reflecting surface, a reflective metal coating disposed on the reflecting surface of the reflector-shaped substrate, and a dichroic coating made of twenty nine alternating layers of SiO₂ and ZnS disposed on the metal coating; and

a light source capsule mounted within the interior of the reflector wherein the light mirror transmits less than 0.5% of light having wavelengths from about 430 nm to about 700 nm and reflects at least about 80% of light having wavelengths from about 800 nm to about 2500 nm.

2. A lamp in accordance with claim 1 wherein the metal coating comprises a metal having a reflection coefficient greater than or equal to about 0.8.

3. A lamp in accordance with claim 1 wherein the metal coating has a thickness less than or equal to 200 nm.

4. A lamp in accordance with claim 1 wherein the metal coating comprises aluminum.

5. A lamp in accordance with claim 1 wherein the metal coating comprises silver.

6. A lamp in accordance with claim 1 wherein the metal coating comprises gold.

7. A lamp in accordance with claim 1 wherein the metal coating comprises rhodium.

8. A lamp in accordance with claim 1 wherein each of said alternating layers of silicon oxide and zinc sulfide, has a respective optical thickness, wherein:

layer 1 comprises SiO₂ with an optical thickness of 30 nm;

layer 2 comprises ZnS with an optical thickness of 162.5 nm;

layer 3 comprises SiO₂ with an optical thickness of 162.5 nm;

layer 4 comprises ZnS with an optical thickness of 162.5 nm;

layer 5 comprises SiO₂ with an optical thickness of 162.5 nm;

layer 6 comprises ZnS with an optical thickness of 162.5 nm;

layer 7 comprises SiO₂ with an optical thickness of 162.5 nm;

layer 8 comprises ZnS with an optical thickness of 162.5 nm;

layer 9 comprises SiO₂ with an optical thickness of 162.5 nm;

layer 10 comprises ZnS with an optical thickness of 162.5 nm;

layer 11 comprises SiO₂ with an optical thickness of 162.5 nm;

layer 12 comprises ZnS with an optical thickness of 135.8 nm;

layer 13 comprises SiO₂ with an optical thickness of 135.8 nm;

layer 14 comprises ZnS with an optical thickness of 135.8 nm;

layer 15 comprises SiO₂ with an optical thickness of 135.8 nm;

layer 16 comprises ZnS with an optical thickness of 135.8 nm;

layer 17 comprises SiO₂ with an optical thickness of 135.8 nm;

layer 18 comprises ZnS with an optical thickness of 135.8 nm;

layer 19 comprises SiO₂ with an optical thickness of 135.8 nm;

layer 20 comprises ZnS with an optical thickness of 110.5 nm;

layer 21 comprises SiO₂ with an optical thickness of 110.5 nm;

layer 22 comprises ZnS with an optical thickness of 110.5 nm;

layer 23 comprises SiO₂ with an optical thickness of 110.5 nm;

layer 24 comprises ZnS with an optical thickness of 110.5 nm;

layer 25 comprises SiO₂ with an optical thickness of 110.5 nm;

layer 26 comprises ZnS with an optical thickness of 110.5 nm;

layer 27 comprises SiO₂ with an optical thickness of 110.5 nm;

layer 28 comprises ZnS with an optical thickness of 110.5 nm;

layer 29 comprises SiO₂ with an optical thickness of 110.5 nm, wherein layer 1 of SiO₂ being disposed on the metal coating.

9. A lamp in accordance with claim 1 wherein the substrate comprises glass.

10. A lamp in accordance with claim 1 wherein the reflector-shaped substrate has a rim and a lens mounted in the rim of the reflector-shaped substrate so as to form a closed lamp.

11. A lamp in accordance with claim 8 wherein the metal coating comprises aluminum.

12. A lamp in accordance with claim 11 wherein the metal coating has a thickness from about 12 nm to about 100 nm.

13. A lamp in accordance with claim 12 wherein the metal coating has an optical thickness of about 100 nm.

14. A lamp in accordance with claim 13 wherein the metal coating comprises a first metal film having an optical thickness of about 50 nm and a second metal film having an optical thickness of about 50 nm.

15. A lamp in accordance with claim 14 wherein the light source is a tungsten halogen light source.

16. A lamp in accordance with claim 14 wherein the light source is an incandescent light source.

17. A lamp in accordance with claim 14 wherein the light source is a metal halide light source.