PROJECTION OBJECTIVE Russian patent published in 1995 - IPC

FIELD: optical instrument engineering. SUBSTANCE: all lenses are simple in five-lens objective. The first lens is positive meniscus, the second and the fourth lenses are negative, the third and the fifth lenses are positive. Positive lenses are made of glass with n_e=1,74, ν_e=50,, and negative lenses are made of glass with 1,62 < n_e< 1,65; 33,6 < ν_e< 34,3. EFFECT: improved efficiency of application in fax machines and so on. 9 dwg, 1 tbl