LENS Russian patent published in 2003 - IPC

FIELD: optics. SUBSTANCE: lens has five components: first component is negative meniscus facing object space with concave surface and bonded of negative and positive lenses, second component is single positive meniscus facing image space with concave surface, third component is single negative meniscus facing image space with concave surface, fourth component is single positive meniscus facing image space with concave surface and fifth component is positive lens cemented from positive and negative lenses and mounted at distance more than 0.47 focal length of lens from fourth component for adjustment. Spectrum-splitting unit which thickness is not less than 0.3 focal length of entire lens is placed between fourth and fifth components. Optical powers and coefficients of linear expansion of components correspond to relations specified in formula of invention. EFFECT: enlarged aperture ratio, raised quality of image in wide spectral range λ=500-900 nm thanks to increase of coefficients of transmission of modulation over entire field of vision and provision for low thermal detuning of lens. 6 dwg, 1 tbl