Optical elements with protective undercoating
An apparatus and method are disclosed for an optical element which may comprise a main optical body comprising a crystal containing halogen atoms; a reflectivity coating for changing the reflectivity of a surface of the main body; and, an intermediate protective layer comprising a material containing free halogen atoms. The crystal may comprise an alkaline earth metal and may comprise fluorine atoms, e.g., calcium fluoride or magnesium fluoride. The intermediate protective layer may comprises a material containing free fluorine atoms, e.g., a material doped with fluorine atoms, e.g., doped fused silica. The intermediate layer comprises an amorphous portion and a polycrystalline portion. The optical element may also comprise a main optical element body; a reflectivity coating comprising a metal halide on an exterior the a surface of the main optical body; and a thin layer of protective outer coating on the reflectivity coating comprising a dense non-porous material thin enough to be transparent to the light of a selected short wavelength. The reflectivity coating may comprise a plurality of layers with at least one layer comprising a metal fluoride and the protective outer coating may comprise a layer of silicon oxyfluoride.
1 . An optical element comprising:
a main optical body comprising a crystal containing halogen atoms;
a reflectivity coating for changing the reflectivity of a surface of the main body; and,
an intermediate protective layer comprising a material containing free halogen atoms.
2 . The apparatus of claim 1 further comprising:
the crystal comprises an alkaline earth metal.
3 . The apparatus of claim 1 further comprising:
the crystal comprises fluorine atoms.
4 . The apparatus of claim 1 further comprising:
the crystal comprises calcium fluoride.
5 . The apparatus of claim 2 further comprising:
the crystal comprises calcium fluoride.
6 . The apparatus of claim 3 further comprising:
the crystal comprises calcium fluoride.
7 . The apparatus of claim 1 further comprising:
the crystal comprises magnesium fluoride.
8 . The apparatus of claim 2 further comprising:
the crystal comprises magnesium fluoride.
9 . The apparatus of claim 3 further comprising:
the crystal comprises magnesium fluoride.
10 . The apparatus of claim 1 further comprising:
the intermediate protective layer comprises a material containing free fluorine atoms.
11 . The apparatus of claim 2 further comprising:
the intermediate protective layer comprises a material containing free fluorine atoms.
12 . The apparatus of claim 3 further comprising:
the intermediate protective layer comprises a material containing free fluorine atoms.
13 . The apparatus of claim 4 further comprising:
the intermediate protective layer comprises a material containing free fluorine atoms.
14 . The apparatus of claim 5 further comprising:
the intermediate protective layer comprises a material containing free fluorine atoms.
15 . The apparatus of claim 6 further comprising:
the intermediate protective layer comprises a material containing free fluorine atoms.
16 . The apparatus of claim 7 further comprising:
the intermediate protective layer comprises a material containing free fluorine atoms.
17 . The apparatus of claim 8 further comprising:
the intermediate protective layer comprises a material containing free fluorine atoms.
18 . The apparatus of claim 9 further comprising:
the intermediate protective layer comprises a material containing free fluorine atoms.
19 . The apparatus of claim 10 further comprising:
the intermediate protective layer comprises a material doped with fluorine atoms.
20 . The apparatus of claim 11 further comprising:
the intermediate protective layer comprises a material doped with fluorine atoms.
21 . The apparatus of claim 12 further comprising:
the intermediate protective layer comprises a material doped with fluorine atoms.
22 . The apparatus of claim 13 further comprising:
the intermediate protective layer comprises a material doped with fluorine atoms.
23 . The apparatus of claim 14 further comprising:
the intermediate protective layer comprises a material doped with fluorine atoms.
24 . The apparatus of claim 15 further comprising:
the intermediate protective layer comprises a material doped with fluorine atoms.
25 . The apparatus of claim 16 further comprising:
the intermediate protective layer comprises a material doped with fluorine atoms.
26 . The apparatus of claim 17 further comprising:
the intermediate protective layer comprises a material doped with fluorine atoms.
27 . The apparatus of claim 18 further comprising:
the intermediate protective layer comprises a material doped with fluorine atoms.
28 . The apparatus of claim 19 further comprising:
the intermediate protective layer comprises doped fused silica.
29 . The apparatus of claim 20 further comprising:
the intermediate protective layer comprises doped fused silica.
30 . The apparatus of claim 21 further comprising:
the intermediate protective layer comprises doped fused silica.
31 . The apparatus of claim 22 further comprising:
the intermediate protective layer comprises doped fused silica.
32 . The apparatus of claim 23 further comprising:
the intermediate protective layer comprises doped fused silica.
33 . The apparatus of claim 24 further comprising:
the intermediate protective layer comprises doped fused silica.
34 . The apparatus of claim 25 further comprising:
the intermediate protective layer comprises doped fused silica.
35 . The apparatus of claim 26 further comprising:
the intermediate protective layer comprises doped fused silica.
36 . The apparatus of claim 37 further comprising:
the intermediate protective layer comprises doped fused silica.
37 . The apparatus of claim 1 further comprising:
the intermediate layer comprises an amorphous portion and a polycrystalline portion.
38 . The apparatus of claim 2 further comprising:
the intermediate layer comprises an amorphous portion and a polycrystalline portion.
39 . The apparatus of claim 3 further comprising:
the intermediate layer comprises an amorphous portion and a polycrystalline portion.
40 . The apparatus of claim 4 further comprising:
the intermediate layer comprises an amorphous portion and a polycrystalline portion.
41 . The apparatus of claim 5 further comprising:
the intermediate layer comprises an amorphous portion and a polycrystalline portion.
42 . The apparatus of claim 6 further comprising:
the intermediate layer comprises an amorphous portion and a polycrystalline portion.
43 . The apparatus of claim 7 further comprising:
the intermediate layer comprises an amorphous portion and a polycrystalline portion.
44 . The apparatus of claim 8 further comprising:
the intermediate layer comprises an amorphous portion and a polycrystalline portion.
45 . The apparatus of claim 9 further comprising:
the intermediate layer comprises an amorphous portion and a polycrystalline portion.
46 . A method of forming an optical element comprising:
providing a main optical body comprising a crystal containing halogen atoms;
applying a reflectivity coating for changing the reflectivity of a surface of the main body; and,
applying an intermediate protective layer comprising a material containing free halogen atoms.
47 . The method of claim 46 further comprising:
the crystal comprises an alkaline earth metal.
48 . The method of claim 46 further comprising:
the crystal comprises fluorine atoms.
49 . The method of claim 46 further comprising:
the crystal comprises calcium fluoride.
50 . The method of claim 47 further comprising:
the crystal comprises calcium fluoride.
51 . The method of claim 48 further comprising:
the crystal comprises calcium fluoride.
52 . The method of claim 46 further comprising:
the crystal comprises magnesium fluoride.
53 . The method of claim 47 further comprising:
the crystal comprises magnesium fluoride.
54 . The method of claim 48 further comprising:
the crystal comprises magnesium fluoride.
55 . The method of claim 49 further comprising:
the intermediate protective layer comprises a material containing free fluorine atoms.
56 . The method of claim 50 further comprising:
the intermediate protective layer comprises a material containing free fluorine atoms.
57 . The method of claim 51 further comprising:
the intermediate protective layer comprises a material containing free fluorine atoms.
58 . The method of claim 52 further comprising:
the intermediate protective layer comprises a material containing free fluorine atoms.
59 . The method of claim 50 further comprising:
the intermediate protective layer comprises a material containing free fluorine atoms.
60 . The method of claim 51 further comprising:
the intermediate protective layer comprises a material containing free fluorine atoms.
61 . The method of claim 52 further comprising:
the intermediate protective layer comprises a material containing free fluorine atoms.
62 . The method of claim 53 further comprising:
the intermediate protective layer comprises a material containing free fluorine atoms.
63 . The method of claim 54 further comprising:
the intermediate protective layer comprises a material containing free fluorine atoms.
64 . The method of claim 55 further comprising:
the intermediate protective layer comprises a material doped with fluorine atoms.
65 . The method of claim 56 further comprising:
the intermediate protective layer comprises a material doped with fluorine atoms.
66 . The method of claim 57 further comprising:
the intermediate protective layer comprises a material doped with fluorine atoms.
67 . The method of claim 58 further comprising:
the intermediate protective layer comprises a material doped with fluorine atoms.
68 . The method of claim 59 further comprising:
the intermediate protective layer comprises a material doped with fluorine atoms.
69 . The method of claim 60 further comprising:
the intermediate protective layer comprises a material doped with fluorine atoms.
70 . The method of claim 61 further comprising:
the intermediate protective layer comprises a material doped with fluorine atoms.
71 . The method of claim 62 further comprising:
the intermediate protective layer comprises a material doped with fluorine atoms.
72 . The method of claim 63 further comprising:
the intermediate protective layer comprises a material doped with fluorine atoms.
73 . The method of claim 64 further comprising:
the intermediate protective layer comprises doped fused silica.
74 . The method of claim 65 further comprising:
the intermediate protective layer comprises doped fused silica.
75 . The method of claim 66 further comprising:
the intermediate protective layer comprises doped fused silica.
76 . The method of claim 67 further comprising:
the intermediate protective layer comprises doped fused silica.
77 . The method of claim 68 further comprising:
the intermediate protective layer comprises doped fused silica.
78 . The method of claim 69 further comprising:
the intermediate protective layer comprises doped fused silica.
79 . The method of claim 70 further comprising:
the intermediate protective layer comprises doped fused silica.
80 . The method of claim 71 further comprising:
the intermediate protective layer comprises doped fused silica.
81 . The method of claim 72 further comprising:
the intermediate protective layer comprises doped fused silica.
82 . The method of claim 46 further comprising:
the intermediate layer comprises an amorphous portion and a polycrystalline portion.
83 . The method of claim 47 further comprising:
the intermediate layer comprises an amorphous portion and a polycrystalline portion.
84 . The method of claim 48 further comprising:
the intermediate layer comprises an amorphous portion and a polycrystalline portion.
85 . The method of claim 49 further comprising:
the intermediate layer comprises an amorphous portion and a polycrystalline portion.
86 . The method of claim 50 further comprising:
the intermediate layer comprises an amorphous portion and a polycrystalline portion.
87 . The method of claim 51 further comprising:
the intermediate layer comprises an amorphous portion and a polycrystalline portion.
88 . The method of claim 52 further comprising:
the intermediate layer comprises an amorphous portion and a polycrystalline portion.
89 . The method of claim 53 further comprising:
the intermediate layer comprises an amorphous portion and a polycrystalline portion.
90 . The method of claim 54 further comprising:
the intermediate layer comprises an amorphous portion and a polycrystalline portion.
92 . An optical element comprising:
a main optical element body;
a reflectivity coating comprising a metal halide on an exterior surface of the main optical body;
a thin layer of protective outer coating on the reflectivity coating comprising a dense non-porous material thin enough to be transparent to the light of a selected short wavelength.
93 . The apparatus of claim 92 further comprising:
the reflectivity coating comprises a plurality of layers with at least one layer comprising a metal fluoride.
94 . The apparatus of claim 92 further comprising:
the protective outer coating comprises a layer of silicon oxyfluoride.
95 . The apparatus of claim 93 further comprising:
the protective outer coating comprises a layer of silicon oxyfluoride.
95 . A method of protecting an optical element comprising:
providing a main optical element body;
coating an exterior surface of the main optical element body with a reflectivity coating comprising a metal halide;
coating an exterior surface of the reflectivity coating with a thin layer of protective outer coating comprising a dense non-porous material thin enough to be transparent to the light of a selected short wavelength.
96 . The method of claim 95 further comprising:
the reflectivity coating comprises a plurality of layers with at least one layer comprising a metal fluoride.
97 . The method of claim 95 further comprising:
the protective outer coating comprises a layer of silicon oxyfluoride.
98 . The method of claim 96 further comprising:
the protective outer coating comprises a layer of silicon oxyfluoride.