Multispectral imaging system comprising new multispectral optics

Patent metadata

Field	Value
Publication number	US-9658105-B2
Application number	US-201514848555-A
Country	US
Kind code	B2
Filing date	Sep 9, 2015
Priority date	Sep 9, 2014
Publication date	May 23, 2017
Grant date	May 23, 2017

Abstract

A compact multispectral imaging system comprising a set of optical elements capable of simultaneously focusing light from one or more spectral bands (SWIR, MWIR, and LWIR) to a common focal plane and a detector capable of capturing the multispectral image, wherein the optical elements comprise optics made from new optical materials or in combination with existing optical materials that transmit in multispectral wavelength regions.

First claim

What is claimed as new and desired to be protected by Letters Patent of the United States is:

1. A compact multispectral imaging system, comprising:
two or more refractive optical elements, wherein the optical elements can simultaneously focus light from shortwave infrared (SWIR) spectral bands, midwave infrared (MWIR) spectral bands, longwave (LWIR) infrared spectral bands, or any combination thereof to a common focal plane, wherein at least one optical element comprises an optical material as defined by one of the following descriptions:
a polycrystalline ceramic material comprising a Group 2 element, a lanthanide, and sulfur, and having greater than 65% transmission in SWIR, MWIR and LWIR wavelength regions, a refractive index of about 2.49 at a wavelength of 3 μm, a SWIR Abbe number (V SWIR ) of about 31, a MWIR Abbe number (V MWIR ) of about 93, a LWIR Abbe number (V LWIR ) of about 20, and a coefficient of thermal expansion (CTE) of about 15×10 −6 /° C.;
an optical glass material comprising arsenic and sulfur and having transmission in SWIR, MWIR and LWIR wavelength regions with a −3 dB electronic edge at about 0.56 μm and a −3 dB multiphonon edge at about 12.7 μm, a refractive index of about 2.40 at a wavelength of 3 μm, a V SWIR of about 23, a V MWIR of about 162, a V LWIR of about 48, a thermo-optic coefficient (dn/dT) of about −17×10 −6 /° C. at a wavelength of 3 μm, a glass transition temperature (T g ) of about 195° C., a viscosity of about 10 8.4 Pa·S at 240° C., and a coefficient of thermal expansion (CTE) of about 26.6×10 −6 /° C.;
an optical glass material comprising Ge, As, and Se and having transmission in SWIR, MWIR and LWIR wavelength regions with a −3 dB electronic edge at about 0.79 μm and a −3 dB multiphonon edge at about 18.2 μm, a refractive index of about 2.71 at a wavelength of 3 μm, a V SWIR of about 15, a V MWIR of about 175, a V LWIR of about 142, a thermo-optic coefficient (dn/dT) of about 39×10 −6 /° C. at a wavelength of 3 μm, a glass transition temperature (T g ) of about 196° C., a viscosity of about 10 8.7 Pa·S at 240° C., and a coefficient of thermal expansion (CTE) of about 23.2×10 −6 /° C.;
an optical glass material comprising Ge, As, S, and Te and having transmission in SWIR, MWIR and LWIR wavelength regions with a −3 dB electronic edge at about 0.89 μm and a −3 dB multiphonon edge at about 12.5 μm, a refractive index of about 2.40 at a wavelength of 3 μm, a V SWIR of about 22, a V MWIR of about 160, a V LWIR of about 48, a thermo-optic coefficient (dn/dT) of about −5.9×10 −6 /° C. at a wavelength of 3 μm, a glass transition temperature (T g ) of about 196° C., a viscosity of about 10 8.8 Pa·S at 240° C., and a coefficient of thermal expansion (CTE) of about 25.6×10 −6 /° C.;
an optical glass material comprising Ge, As, and Se and having transmission in SWIR, MWIR and LWIR wavelength regions with a −3 dB electronic edge at about 0.78 μm and a −3 dB multiphonon edge at about 17.5 μm, a refractive index of about 2.65 at a wavelength of 3 μm, a V SWIR of about 16, a V MWIR of about 201, a V LWIR of about 235, a thermo-optic coefficient (dn/dT) of about −18.4×10 −6 /° C. at a wavelength of 3 μm, a glass transition temperature (T g ) of about 201, a viscosity of about 10 101 Pa·S at 240° C., and a coefficient of thermal expansion (CTE) of about 30.2×10 −6 /° C.;
an optical glass material comprising Ge, As, and Se and having transmission in SWIR, MWIR and LWIR wavelength regions with a −3 dB electronic edge at about 0.74 μm and a −3 dB multiphonon edge at about 17.2 μm, a refractive index of about 2.48 at a wavelength of 3 μm, a V SWIR of about 19, a V MWIR of about 200, a V LWIR of about 127, a thermo-optic coefficient (dn/dT) of about 8.3×10 −6 /° C. at a wavelength of 3 μm, a glass transition temperature (T g ) of about 192, a viscosity of about 10 97 Pa·S at 240° C., and a coefficient of thermal expansion (CTE) of about 26×10 −6 /° C.;
an optical glass material comprising Ge, As, Se, and Te and having transmission in MWIR and LWIR wavelength regions with a −3 dB electronic edge at about 1.43 μm and a −3 dB multiphonon edge at about 18.2 μm, a refractive index of about 3.18 at a wavelength of 3 μm, a V MWIR of about 111, a V LWIR of about 258, a thermo-optic coefficient (dn/dT) of about 177×10 −6 /° C. at a wavelength of 3 μm, a glass transition temperature (T g ) of about 191, a viscosity of about 10 87 Pa·S at 240° C., and a coefficient of thermal expansion (CTE) of about 18.3×10 −6 /° C.;
an optical glass material comprising Ge, As, and S and having transmission in SWIR, MWIR and LWIR wavelength regions with a −3 dB electronic edge at about 0.57 μm and a −3 dB multiphonon edge at about 12.7 μm, a refractive index of about 2.39 at a wavelength of 3 μm, a V SWIR of about 24, a V MWIR of about 161, a V LWIR of about 47, a thermo-optic coefficient (dn/dT) of about −6.1×10 −6 /° C. at a wavelength of 3 μm, a glass transition temperature (T g ) of about 201, a viscosity of about 10 8.7 Pa·S at 240° C., and a coefficient of thermal expansion (CTE) of about 25.3×10 −6 /° C.;
an optical glass material comprising Ge, As, and Se and having transmission in SWIR, MWIR and LWIR wavelength regions with a −3 dB electronic edge at about 0.79 μm and a −3 dB multiphonon edge at about 18.9 μm, a refractive index of about 2.67 at a wavelength of 3 μm, a V SWIR of about 15, a V MWIR of about 189, a V LWIR of about 185, a thermo-optic coefficient (dn/dT) of about 1.5×10 −6 /° C. at a wavelength of 3 μm, a glass transition temperature (T g ) of about 193, a viscosity of about 10 8.8 Pa·S at 240° C., and a coefficient of thermal expansion (CTE) of about 25.7×10 −6 /° C.;
an optical glass material comprising Ge, As, S, and Se and having transmission in SWIR, MWIR and LWIR wavelength regions with a −3 dB electronic edge at about 0.61 μm and a −3 dB multiphonon edge at about 12.8 μm, a refractive index of about 2.42 at a wavelength of 3 μm, a V SWIR of about 23, a V MWIR of about 162, a V LWIR of about 50, a thermo-optic coefficient (dn/dT) of about −3.9×10 −6 /° C. at a wavelength of 3 μm, a glass transition temperature (T g ) of about 197, a viscosity of about 10 86 Pa·S at 240° C., and a coefficient of thermal expansion (CTE) of about 25.1×10 −6 /° C.;
an optical glass material comprising Ge, As, and Se and having transmission in SWIR, MWIR and LWIR wavelength regions with a −3 dB electronic edge at about 0.74 μm and a −3 dB multiphonon edge at about 17.5 μm, a refractive index of about 2.53 at a wavelength of 3 μm, a V SWIR of about 18, a V MWIR of about 195, a V LWIR of about 134, a thermo-optic coefficient (dn/dT) of about 23.5×10 −6 /° C. at a wavelength of 3 μm, a glass transition temperature (T g ) of about 191, a viscosity of about 10 89 Pa·S at 240° C., and a coefficient of thermal expansion (CTE) of about 27×10 −61 ° C.;
an optical glass material comprising As, S, and Se and having transmission in SWIR, MWIR and LWIR wavelength regions with a −3 dB electronic edge at about 0.62 μm and a −3 dB multiphonon edge at about 12.9 μm, a refractive index of about 2.43 at a wavelength of 3 μm, a V SWIR of about 23, a V MWIR of about 164, a W LWIR of about 52, a thermo-optic coefficient (dn/dT) of about −0.3×10 −6 /° C. at a wavelength of 3 μm, a glass transition temperature (T g ) of about 196, a viscosity of about 10 8.2 Pa·S at 240° C., and a coefficient of thermal expansion (CTE) of about 25.5×10 −6 /° C.;
an optical glass material comprising As, S, and Se and having transmission in SWIR, MWIR and LWIR wavelength regions with a −3 dB electronic edge at about 0.64 μm and a −3 dB multiphonon edge at about 13 μm, a refractive index of about 2.46 at a wavelength of 3 μm, a V SWIR of about 21, a V MWIR of about 165, a V LWIR of about 56, a thermo-optic coefficient (dn/dT) of about 0.8×10 −6 /° C. at a wavelength of 3 μm, a glass transition temperature

Assignees

• Bayya Shyam S
• Gibson Daniel J
• Nguyen Vinh Q
• Sanghera Jasbinder S
• Vizgaitis Jay
• Us Navy

Inventors

• Bayya Shyam S
• Gibson Daniel J
• Nguyen Vinh Q
• Sanghera Jasbinder S
• Vizgaitis Jay

Classifications

• G01J3/0208

  using focussing or collimating elements, e.g. lenses or mirrors; performing aberration correction · CPC title

• G01J3/2823 Primary

  Imaging spectrometer · CPC title

• G01J2003/2826

  Multispectral imaging, e.g. filter imaging · CPC title

• G02B13/146

  with corrections for use in multiple wavelength bands, such as infrared and visible light, e.g. FLIR systems · CPC title

• G02B1/02

  made of crystals, e.g. rock-salt, semi-conductors (G02B1/08 takes precedence) · CPC title