DOUBLE-CHANNEL DAY AND NIGHT VIEWING DEVICE Russian patent published in 2003 - IPC

FIELD: electronic devices. SUBSTANCE: double-channel day and night viewing device has day viewing channel incorporating lens, erecting system, and ocular; night viewing channel incorporating image converter lens, projection lens, and ocular common for both channels; optical switching system incorporating four optical deflectors. Night-viewing channel lens is built of two components of which first one is lens of day viewing channel. Focal power of night viewing channel second component is higher than that of day viewing channel lens by 1.5 to 4 times. Second component of night viewing channel lens has two groups of lenses spaced apart through large air gap, absolute power of second group of lenses being higher than that of first group by 1.2 to 1.7 times and air gap may be greater than focal distance of second component of night viewing channel lens by 1.5 to 4 times. EFFECT: greatly reduced size of device. 9 cl, 1 dwg