Compact, high cold shield efficiency optical system

Patent · Mon Feb 13 23:00:00 EST 1984

OSTI ID:6672811

Gibbons, R C

An optical system is disclosed for use with a radiant energy receiver which provides high cold shield efficiency and is compact; further the optical system is temperature tolerant to maintain focus with changes in temperature and wavelength without operator intervention. The optical system has primary utility in the infrared region of the spectrum and where a two dimensional array of detectors senses the infrared radiant energy or flux from the scene of interest. The optical system is comprised of a window for environmental protection and two objective mirrors for folding and focusing the scene of interest on a first focal plane. Relay optical means, which may be comprised of one or more optical elements, relays and relocates the first focal plane to a second focal plane which is coincident with the surface of the two dimensional detector array; the relay optical means also forms an exit pupil (the image of the aperture stop) around which the aperture of a cold shield is positioned to minimize extraneous radiant energy falling on the detector array. Using a positive and negative refractive lens and judicious selection of materials allows the relay optical means to automatically compensate for variation in its index of refraction as a function of temperature and wavelength.

• Assignee: Texas Instruments Incorporated
• Patent Number(s): US 4431917
• OSTI ID: 6672811
• Country of Publication: United States
• Language: English

Related Subjects

440300* -- Miscellaneous Instruments-- (-1989)
47 OTHER INSTRUMENTATION
APERTURES
BACKGROUND RADIATION
CHROMATIC ABERRATIONS
ELECTROMAGNETIC RADIATION
FLUX DENSITY
FOCUSING
INFRARED RADIATION
LENSES
MEASURING INSTRUMENTS
MIRRORS
OPENINGS
OPTICAL PROPERTIES
OPTICAL SYSTEMS
PHYSICAL PROPERTIES
RADIANT FLUX DENSITY
RADIATION DETECTORS
RADIATIONS
REFRACTIVITY
SHIELDING
TEMPERATURE DEPENDENCE