First surface mirror with silicon-metal oxide nucleation layer

1. A mirror comprising:

a substrate supporting a coating, wherein the coating includes at least a reflective layer comprising aluminum, first and second dielectric layers, and at least one layer comprising silicon aluminum oxide, wherein the layer comprising silicon aluminum oxide is located closer to the substrate than are the reflective layer and the dielectric layers, and wherein the reflective layer comprising aluminum is located between the substrate and the dielectric layers;

wherein the layer comprising silicon aluminum oxide is located directly under and contacting the reflective layer comprising aluminum in order to improve at least durability of the first surface mirror; and

wherein the layer comprising silicon aluminum oxide is graded in at least three different respects so that the layer comprising silicon aluminum oxide (a) contains more oxygen at a location closer to the substrate than at a location further from the substrate; (b) contains more Si at a location closer to the substrate than at a location further from the substrate; and (c) contains more Al at a location closer to the reflective layer than at a location further from the reflective layer.

2. The mirror of claim 1 , wherein the mirror is a first surface mirror and is located in a projection television apparatus, and wherein the reflective layer comprising aluminum reflects incoming light away from the substrate.

3. The mirror of claim 1 , wherein the layer comprising silicon aluminum oxide comprises from about 2-67% oxygen, from about 33-98% Si and Al together, and an Si/Al ratio of from about 0.05 to 100.

4. The mirror of claim 1 , wherein the layer comprising silicon aluminum oxide is in direct contact with both the substrate and the reflective layer comprising aluminum.

5. The mirror of claim 1 , wherein the mirror is a first surface mirror and reflects at least about 80% of incoming visible light at about 550 nm.

6. The mirror of claim 1 , wherein at least one of the gradings (a)-(c) is a substantially continuously progressive grading through the thickness of the layer comprising silicon aluminum oxide.

7. The mirror of claim 1 , wherein two or three of the gradings (a)-(c) are substantially continuously progressive gradings through the thickness of the layer comprising silicon aluminum oxide.

8. The mirror of claim 1 , wherein the first dielectric layer comprises silicon oxide and the second dielectric layer comprises titanium oxide.

9. The mirror of claim 1 , wherein the first and second dielectric layers are each provided on the substrate over at least the reflective layer, and wherein the second dielectric layer is an outermost layer of the first surface mirror, and wherein the second dielectric layer has an index of refraction value “n” greater than an index of refraction value “n” of the first dielectric layer.

10. The mirror of claim 9 , wherein the second dielectric layer has an index of refraction value “n” of from about 2.2 to 2.6, and the first dielectric layer has an index of refraction value “n” of from about 1.4 to 1.6.

11. The mirror of claim 1 , wherein the layer comprising silicon aluminum oxide is from about 5 to 50 nm thick.

12. The mirror of claim 1 , wherein the substrate comprises soda lime silica based glass.

13. The mirror of claim 1 , further comprising another layer comprising aluminum oxide and/or silicon aluminum oxide located above and directly contacting the reflective layer.

14. A first surface mirror comprising:

a substrate supporting a coating, wherein the coating includes at least a reflective layer, first and second dielectric layers, and at least one layer comprising silicon aluminum oxide, wherein the layer comprising silicon aluminum oxide is located closer to the substrate than are the reflective layer and the dielectric layers, and wherein the reflective layer is located between the substrate and the dielectric layers;

wherein the layer comprising silicon aluminum oxide is located directly under and contacting the reflective layer in order to improve at least durability of the first surface mirror; and

wherein the layer comprising silicon aluminum oxide is graded in at least two of the following three different respects: (a) the layer comprising silicon aluminum oxide comprises more oxygen at a location closer to the substrate than at a location further from the substrate; (b) the layer comprising silicon aluminum oxide comprises more Si at a location closer to the substrate than at a location further from the substrate; and (c) the layer comprising silicon aluminum oxide comprises more Al at a location closer to the reflective layer than at a location further from the reflective layer.

15. The first surface mirror of claim 14 , wherein the mirror is located in a projection television apparatus, and wherein the reflective layer comprises aluminum and reflects incoming light away from the substrate.

16. The first surface mirror of claim 14 , wherein the layer comprising silicon aluminum oxide comprises from about 2-30% oxygen, from about 70-98% Si and Al together, and an Si/Al ratio of from about 0.05 to 1.5.

17. The first surface mirror of claim 14 , wherein the layer comprising silicon aluminum oxide is in direct contact with both the substrate and the reflective layer.

18. The first surface mirror of claim 14 , wherein the mirror reflects at least about 80% of incoming visible light at about 550 nm.

19. The first surface mirror of claim 14 , wherein at least one of the gradings (a)-(c) is a substantially continuously progressive grading through the thickness of the layer comprising silicon aluminum oxide.

20. The first surface mirror of claim 14 , wherein the layer comprising silicon aluminum oxide is from about 5 to 50 nm thick.

21. A first surface mirror comprising:

a substrate supporting a coating, wherein the coating includes at least a reflective layer, at least one dielectric layer, and at least one layer comprising silicon aluminum oxide, wherein the layer comprising silicon aluminum oxide is located closer to the substrate than are any of the reflective layer and the dielectric layer, and wherein the reflective layer is located between the substrate and the dielectric layer;

wherein the layer comprising silicon aluminum oxide is located directly under and contacting the reflective layer in order to improve at least durability of the first surface mirror, and wherein the reflective layer reflects incoming light away from the glass substrate; and

wherein the layer comprising silicon aluminum oxide is more oxided at a location closer to the substrate than at a location further from the substrate.

22. The first surface mirror of claim 21 , wherein the first surface mirror is located in a projection television apparatus.

23. The first surface mirror of claim 21 , wherein the layer comprising silicon aluminum oxide comprises from about 2-30% oxygen, from about 70-98% Si and Al together, and an Si/Al ratio of from about 0.6 to 1.5.