EXPRESSION OF MRF4 IN CRANIAL REGIONS OF XENOPUS LAEVIS EMBRYOS

Six-component projection lens systems (13) for use in CRT projection televisions (10) are provided. To provide an improved overall modulation transfer function across the field of view of the lens, the system's first lens element (L1) has an object side surface (S2) which has a best fit spherical surface which is convex to the CRT (16). To provide partial axial color correction, the system's second lens element (L2) is made of a high dispersion material, such as styrene.