Patent ID: 9709699
Date: 2017-07-18
CPC Classifications: B82Y,G02B,Y10S

Claim:
1. An optical system comprising at least one athermal lens integrally formed of a nano-nano composite optical ceramic (NNCOC) material having a crystalline structure and comprising a first plurality of nanograins of a first component nanograin material having a first coefficient of thermal expansion, a first thermo-optic coefficient, and a first index of refraction, and a separate, second plurality of nanograins of a different second component nanograin material having a second coefficient of thermal expansion, a second thermo-optic coefficient, and a second index of refraction, each of the first and second pluralities of nanograins having a sub-micron grain size in a direction of light transmission through the at least one athermal lens, and a volumetric ratio of the first and second pluralities of nanograins in the nano-nano composite optical ceramic material being substantially non-varying throughout the at least one athermal lens and selected to achieve a substantially constant focal length of the optical system over an operating temperature range from about −40° C. to about 70° C., and based on a first relationship between the first coefficient of thermal expansion and the first index of refraction and a rate of change of the first index of refraction over the operating temperature range, and a second relationship between the second coefficient of thermal expansion and the second index of refraction and a rate of change of the second index of refraction over the operating temperature range, the crystalline structure of the nano-nano composite optical ceramic material obtained by sintering the first component nanograin material and the second component nanograin material and applying a hot isostatic press.