Dual-band passively athermal optical lens system
First Claim
1. An optical system comprising:
- at least one beam of infrared light including both mid-wave infrared light and long-wave infrared light;
an external entrance pupil, for infrared light to be shown through, being located in front of the optical system;
a transparent formed material through which the at least one beam of infrared light, including both mid-wave infrared light and long-wave infrared light, travels;
a series of optical materials spaced at varying distances from one another by a series of spacers, a respective spacer, of the series of spacers, separating each adjacent pair of optical materials from one another during operation of the optical system;
a Dewar window, and a filter being located between the last optical material and a focal plane;
the series of optical materials and spacers being selected and arranged so as to simultaneously focus both the mid-wave infrared light and the long-wave infrared light of the at least one beam of infrared light on the focal plane; and
the series of spacers varying the spacing of the optical materials from one another, during operation of the optical system, so that the optical system is passively athermal over an operating temperature range from about −
40°
C. to about 60°
C.
1 Assignment
0 Petitions
Accused Products
Abstract
An optical lens system for focusing light on a focal plane for detection by a detector device. The optical lens system comprises a series of optical materials including first and last optical materials with a plurality of other optical materials located therebetween. A housing accommodates the series of optical materials, and each of the optical materials is spaced a desired distance from one another. An external entrance pupil supplies infrared light to the series of optical materials of the optical lens system, and the entrance pupil is located in front of the first optical material. A Dewar window and a filter are located between the last optical material and the focal plane. The optical materials are selected and arranged to focus simultaneously both mid-wave infrared light and long-wave infrared light on the focal plane over a wide temperature range.
12 Citations
20 Claims
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1. An optical system comprising:
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at least one beam of infrared light including both mid-wave infrared light and long-wave infrared light; an external entrance pupil, for infrared light to be shown through, being located in front of the optical system; a transparent formed material through which the at least one beam of infrared light, including both mid-wave infrared light and long-wave infrared light, travels; a series of optical materials spaced at varying distances from one another by a series of spacers, a respective spacer, of the series of spacers, separating each adjacent pair of optical materials from one another during operation of the optical system; a Dewar window, and a filter being located between the last optical material and a focal plane; the series of optical materials and spacers being selected and arranged so as to simultaneously focus both the mid-wave infrared light and the long-wave infrared light of the at least one beam of infrared light on the focal plane; and the series of spacers varying the spacing of the optical materials from one another, during operation of the optical system, so that the optical system is passively athermal over an operating temperature range from about −
40°
C. to about 60°
C. - View Dependent Claims (2, 3, 4)
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5. An optical lens system for receiving light, via an entrance pupil, and focusing light on a focal plane for detection by a detector device, the optical lens system comprising:
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a series of optical materials comprising a first optical material and a last optical material with a plurality of other optical materials located between the first optical material and the last optical material; a housing accommodating the series of optical materials, and each of the optical materials being spaced a desired distance from one another; the external entrance pupil for supplying infrared light to the series of optical materials of the optical lens system, and the entrance pupil being located in front of the series of optical materials; at least one beam of infrared light passing through the external entrance pupil and through the series of optical materials accommodated within the housing; a Dewar window and a filter being located between the last optical material and the focal plane; each of the optical materials, of the series of optical materials of the optical lens system, being spaced from an adjacent optical material by a spacer which is selected and arranged to correspondingly expand or contract, due to temperature changes of the optical lens system, and thereby minutely ater the relative spacing of each the series of optical materials from one another and simultaneously focus both mid-wave infrared light and long-wave infrared light, of the at least one beam of infrared light, on the focal plane over an operating temperature range from about −
40°
C. to about 60°
C. - View Dependent Claims (6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
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18. An optical lens system for receiving light, via an entrance pupil, and focusing light on a focal plane for detection by a detector device, the optical lens system comprising:
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a series of optical materials comprising a first optical material and a last optical material with a plurality of other optical materials located between the first optical material and the last optical material; a housing accommodating the series of optical materials and each of the optical materials being spaced a desired distance from one another; the external entrance pupil for supplying infrared light to the series of optical materials of the optical lens system, and the entrance pupil being located in front of the series of optical materials; at least one beam of infrared light passing through the external entrance pupil and through the series of optical materials accommodated within the housing; a Dewar window and a filter being located between the last optical material and the focal plane; and the series of optical materials are selected and arranged so as to simultaneously focus both mid-wave infrared light and long-wave infrared light of the at least one beam of infrared light on the focal plane; wherein the series of optical materials of the optical lens system comprises; a first series of optical lens which focuses an image of the at least one beam of infrared light at a preliminary imaging plane located between the first and the last optical materials, and a second series of optical lens which reexpand the at least one beam of infrared light, focused at the preliminary imaging plane, and refocuses the at least one beam of infrared light at the focal plane. - View Dependent Claims (19, 20)
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Specification