Patent US4733926A successfully refreshed from Google Patents.
US4733926A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Infrared polarizing beamsplitter
Assignee: Lockheed Martin Corp
•
Filing: 1986-11-10
•
Granted: 1988-03-29
•
Expires: 2006-11-10
Abstract
Abstract A polarizing cube beamsplitter, which is designed for infrared applications, comprises two 45 DEG prisms made of ZnSe. A first anti-reflection layer, which is a Herpin equivalent layer consisting of the triad of sublayers ZnS-ZnSe-Zns, is deposited onto the hypotenuse of a first one of the prisms. Then, a polarizing stack consisting of a plurality of pairs of thin-film layers of alternating high and low refractive indices is formed on the first anti-reflection layer. One layer in each pair of thin-film layers in the polarizing stack is a Herpin equivalent layer consisting of the triad of sub-layers Te-ZnSe-Te, and the other layer in each pair is a thin film of ZnSe. A layer of prism material ZnSe, which is thick enough to be optically polished, is then formed on the second anti-reflection layer. The hypotenuse of the second prism is likewise optically polished, and is pressed onto the optically polished layer of prism material to form a bond. The resulting beamsplitter is of cubic configuration.
Inventors
- 👤 Alan Title
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:54
CPC Classifications
G; G02; G02B; G02B1/00; G02B1/08; G02B27/00; G02B27/28; G02B27/283
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
151 words
A method of fabricating a polarizing beamsplitter for separating s and p components of an infrared beam, said method comprising the steps of: (a) forming a coating on a surface of a first prism, said coating comprising a stack of substantially identical pairs of thin-film layers, each pair of thin-film layers comprising a first layer of relatively high refractive index and a second layer of relatively low refractive index, one of said first and second layers of each pair of thin-film layers being a Herpin equivalent layer consisting of a triad of sub-layers, said Herpin equivalent layer having an equivalent refractive index that is related to the refractive index of the other of said first and second layers so that the p component of said beam is substantially undeviated and unreflected in passing through each pair of thin-film layers, and (b) bonding a surface of a second prism to said coating.
Claim 2
Independent Claim
151 words
A method of fabricating a polarizing beamsplitter for separating s and p components of an infrared beam, said method comprising the steps of: (a) forming a coating on a surface of a first prism, said coating comprising a stack of substantially identical pairs of thin-film layers, each pair of thin-film layers comprising a first layer of relatively high refractive index and a second layer of relatively low refractive index, one of said first and second layers of each pair of thin-film layers being a Herpin equivalent layer consisting of a triad of sub-layers, said Herpin equivalent layer having an equivalent refractive index that is related to the refractive index of the other of said first and second layers so that the p component of said beam is substantially undeviated and unreflected in passing through each pair of thin-film layers, and (b) bonding a surface of a second prism to said coating.
Claim 3
Dependent Claim
46 words
The method of claim 1 wherein said coating further comprises a first anti-reflection layer formed on said surface of said first prism, the first layer of an initial pair in said stack of substantially identical pairs of thin-film layers being deposited upon said first anti-reflection layer.
Claim 4
Dependent Claim
38 words
The method of claim 2 wherein said coating further comprises a second anti-reflection layer, said second anti-reflection layer being formed on the second layer of a final pair in said stack of substantially identical pairs of thin-film layers.
Claim 5
Dependent Claim
71 words
The method of claim 3 wherein each of said first and second anti-reflection layers is a Herpin equivalent layer consisting of a triad of sub-layers, said equivalent layer having an equivalent refractive index that is related to the refractive indices of said prism and of said equivalent layer of each of said pairs of thin-film layers in said stack so that reflection of the p component of said beam is minimized.
Claim 6
Dependent Claim
65 words
The method of claim 4 wherein said coating further comprises a layer of prism material deposited upon said second anti-reflection layer, said layer of prism material being optically polished, and wherein said surface of said second prism is also optically polished, said surface of said second prism being bonded to said coating by being pressed into contact with said optically polished layer of prism material.
Claim 7
Dependent Claim
80 words
The method of claim 5 wherein said first and second prisms are made of ZnSe, each of said first and second anti-reflection layers is a triad of sub-layers comprising ZnS, ZnSe and ZnS in succession, said first layer of each of said pairs of thin-film layers in said stack is a triad of sub-layers comprising Te, ZnSe and Te in succession, and said second layer of each of said pairs of thin-film layers in said stack is made of ZnSe.
Claim 8
Dependent Claim
49 words
The method of claim 5 wherein each of said first and second prisms is substantially a 45° prism, said coating is formed on the hypotenuse of said first prism, and the surface of said second prism that is bonded to said coating is the hypotenuse of said second prism.
Claim 9
Dependent Claim
149 words
A polarizing beamsplitter for separating s and p components of an infrared beam, said beamsplitter being fabricated by the steps of: (a) forming a coating on a surface of a first prism, said coating comprising a stack of substantially identical pairs of thin-film layers, each pair of thin-film layers comprising a first layer of relatively high refractive index and a second layer of relatively low refractive index, one of said first and second layers of each pair of thin-film layers being a Herpin equivalent layer consisting of a triad of sub-layers, said Herpin equivalent layer having an equivalent refractive index that is related to the refractive index of the other of said first and second layers so that the p component of said beam is substantially undeviated and unreflected in passing through said pair of thin-film layers, and (b) bonding a surface of a second prism to said coating.
Claim 10
Dependent Claim
149 words
A polarizing beamsplitter for separating s and p components of an infrared beam, said beamsplitter being fabricated by the steps of: (a) forming a coating on a surface of a first prism, said coating comprising a stack of substantially identical pairs of thin-film layers, each pair of thin-film layers comprising a first layer of relatively high refractive index and a second layer of relatively low refractive index, one of said first and second layers of each pair of thin-film layers being a Herpin equivalent layer consisting of a triad of sub-layers, said Herpin equivalent layer having an equivalent refractive index that is related to the refractive index of the other of said first and second layers so that the p component of said beam is substantially undeviated and unreflected in passing through said pair of thin-film layers, and (b) bonding a surface of a second prism to said coating.
Claim 11
Dependent Claim
46 words
The beamsplitter of claim 8 wherein said coating further comprises a first anti-reflection layer formed on said surface of said first prism, the first layer of an initial pair in said stack of substantially identical pairs of thin-film layers being deposited upon said first anti-reflection layer.
Claim 12
Dependent Claim
38 words
The beamsplitter of claim 9 wherein said coating further comprises a second anti-reflection layer, said second anti-reflection layer being formed on the second layer of a final pair in said stack of substantially identical pairs of thin-film layers.
Claim 13
Dependent Claim
71 words
The beamsplitter of claim 10 wherein each of said first and second anti-reflection layers is a Herpin equivalent layer consisting of a triad of sub-layers, said equivalent layer having an equivalent refractive index that is related to the refractive indices of said prism and of said equivalent layer of each of said pairs of thin-film layers in said stack so that reflection of the p component of said beam is minimized.
Claim 14
Dependent Claim
64 words
The beamsplitter of claim 11 wherein said coating further comprises a layer of prism material deposited upon said second anti-reflection layer, said layer of prism material being optically polished, and wherein said surface of said second prism is also optically polished, said surface of said prism being bonded to said coating by being pressed into contact with said optically polished layer of prism material.
Claim 15
Dependent Claim
80 words
The beamsplitter of claim 12 wherein said first and second prisms are made of ZnSe, each of said first and second anti-reflection layers is a triad of sub-layers comprising ZnS, ZnSe and ZnS in succession, said first layer of each of said pairs of thin-film layers in said stack is a triad of sub-layers comprising Te, ZnSe and Te in succession, and said second layer of each of said pairs of thin-film layers in said stack is made of ZnSe.
Claim 16
Dependent Claim
49 words
The beamsplitter of claim 12 wherein each of said first and second prisms is substantially a 45° prism, said coating is formed on the hypotenuse of said first prism, and the surface of said second prism that is bonded to said coating is the hypotenuse of said second prism.
Claim 17
Dependent Claim
96 words
A polarizing beamsplitter for separating s and p components of an infrared beam, said beamsplitter comprising a first prism, a coating on a surface of said first prism, and a second prism, a surface of said second prism being bonded to said coating, said first and second prisms being made of the same material, said coating comprising a plurality of thin-film layers, each of said thin-film layers being made of one of only three different materials, one of said three different coating materials being the same material from which said first and second prisms are made.
Claim 18
Dependent Claim
96 words
A polarizing beamsplitter for separating s and p components of an infrared beam, said beamsplitter comprising a first prism, a coating on a surface of said first prism, and a second prism, a surface of said second prism being bonded to said coating, said first and second prisms being made of the same material, said coating comprising a plurality of thin-film layers, each of said thin-film layers being made of one of only three different materials, one of said three different coating materials being the same material from which said first and second prisms are made.
Claim 19
Dependent Claim
48 words
The beamsplitter of claim 15 wherein each of said first and second prisms is substantially a 45° prism, said coating being formed on the hypotenuse of said first prism, said surface of said second prism that is bonded to said coating being the hypotenuse of said second prism.
Claim 20
Dependent Claim
21 words
The beamsplitter of claim 15 wherein said surface of said second prism is bonded to said coating by optically polished contact.
Claim 21
Dependent Claim
58 words
The beamsplitter of claim 15 wherein said coating comprises a first layer of relatively high refractive index and a second layer of relatively low refractive index, the refractive indices of said first and second layers being related to each other so that the p component of said beam is substantially undeviated and unreflected in passing through said coating.
Claim 22
Dependent Claim
66 words
The beamsplitter of claim 18 wherein one of said first and second layers of said coating is an equivalent layer consisting of a triad of sub-layers, said equivalent layer having an equivalent refractive index related to the refractive index of the other of said first and second layers so that the p component of said beam is substantially undeviated and unreflected in passing through said coating.
Claim 23
Dependent Claim
63 words
The beamsplitter of claim 19 wherein said coating comprises a number of pairs of said first and second layers, and said pairs of said first and second layers being formed into a stack, the number of said pairs of said first and second layers in said stack being sufficient to cause reflection of a detectable amount of the s component of said beam.
Claim 24
Dependent Claim
42 words
The beamsplitter of claim 20 wherein said coating further comprises a first anti-reflection layer formed on said surface of said first prism, the first layer of an initial pair of said layers in said stack being deposited upon said first anti-reflection layer.
Claim 25
Dependent Claim
34 words
The beamsplitter of claim 21 wherein said coating further comprises a second anti-reflection layer, said second anti-reflection layer being formed on the second layer of a final pair of said layers in said stack.
Claim 26
Dependent Claim
72 words
The beamsplitter of claim 22 wherein each of said first and second anti-reflection layers is an equivalent layer consisting of a triad of sub-layers, said equivalent layer having an equivalent refractive index that is related to the refractive indices of said first prism and of said equivalent layer of said one of said first and second layers in said stack so that reflection of the p component of said beam is minimized.
Claim 27
Dependent Claim
65 words
The beamsplitter of claim 23 wherein said coating further comprises a layer of prism material deposited upon said second anti-reflection layer, said layer of prism material being optically polished, and wherein said surface of said second prism is also optically polished, said surface of said second prism being bonded to said coating by being pressed into contact with said optically polished layer of prism material.
Claim 28
Dependent Claim
80 words
The beamsplitter of claim 24 wherein said first and second prisms are made of ZnSe, each of said first and second anti-reflection layers is a triad of sub-layers coprising ZnS, ZnSe and ZnS in succession, said first layer of each of said pairs of thin-film layers in said stack is a triad of sub-layers comprising Te, ZnSe and Te in succession, and said second layer of each of said pairs of thin-film layers in said stack is made of ZnSe.
References Cited (Backward Citations)
US4229066A
Cited
US4627688A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-03-29 | 1991-09-28 | 1992-03-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-03-29 | 1995-09-28 | 1996-03-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-03-29 | 1999-09-28 | 2000-03-29 | $7700.00 | Window Closed / Lapsed |