Thermally stabilized optical system

A temperature-stabilized wide angle lens system, having a fixed effective focal length, F, and having half field of view (FOV) of at least 90 degree, the temperature-stabilized wide angle lens system comprising:

• a first lens group consisting of a first lens, a second lens and a third lens;
• a second lens group consisting of a fourth lens, a fifth lens, a sixth lens, and a seventh lens;
• a third lens group consisting of an eighth lens, a ninth lens, and a tenth lens, the first through tenth lenses disposed in sequential order along an optical axis of the wide angle lens system from an object side to an image side thereof, and
• wherein the first through tenth lenses cooperate to provide the fixed effective focal length, and the first through tenth lenses are configured to:
• i. maintain F such that F changes by less than 1 micron over a temperature range of 20° C. to 50° C., and/or
• ii. have less than 1 micron of lateral color throughout a half field of view between 55 degrees and 105 degrees for all wavelengths of light between 430 nm-650 nm throughout the temperature range of 20° C. to 50° C., and/or
• iii. maintain an MTF at 156 lp/mm greater than 30% throughout a half field of view from 55 degrees to at least 90 degrees for all wavelengths of light between 430 nm-650 nm throughout the temperature range of 20° C. to 50° C., and/or
• iv. provide an f-number of 2.4 or less,
• whereby thermal stability of the wide angle lens system is achieved.