Four element objective lens for CCD imaging measurement chamber - comprises two meniscus collimating elements, each with bi-concave flint glass component, on opposite sides of iris

摘要

The meniscus lens element (1) on the object side has only a low refractive power (negative or positive) and is formed of three components, including a biconcave lens of short flint glass between two collecting lenses of heavy crown glass. An iris (2) separates it from another three component meniscus lens element (3) which divides the image plane and is matched to the focal surface. The structure affords sufficient refractive power for fully apochromatic performance. USE/ADVANTAGE - For remote sensing of the Earth or other planets, an extremely compact lens of high resolution in the 400 to 1000 nm wavelength range covers a field of view of at least plus or minus 20 deg.