OPTICAL SYSTEM OF BINOCULAR OBSERVATION DEVICE Russian patent published in 1995 - IPC

FIELD: optical instrumentation engineering. SUBSTANCE: optical system has two channels which optical axes are placed at angle not less than 90 deg relative to each other. Each channel is made in the form of lens including single negative meniscus 4 facing space of objects with convexity and biconvex lens 5 of prism inversion system 2 and eye-piece 3 incorporating meniscus 8 of biconcave 9 and biconvex 10 lenses cemented together, single biconvex 11 and positive 12 lenses. Difference of refractive indices of materials of biconcave 9 and biconvex 10 lenses of meniscus of eye-piece 3 is not less than 0.25 and difference of coefficients of average dispersion is not less than 40. In each of channels lens 5 is made of biconvex lens 6 and positive meniscus 7. Meniscus 8 of eye-piece is produced positive and positive lens 12 is manufactured in the form of meniscus facing space of images with concavity. Difference of refractive indices of materials of lens 6 and meniscus 7 of lens 5 is not less than 0.2 and ratio of thicknesses of lenses 9 and 10 is chosen as 1:1.55. Binocular device has magnification of X1, linear field 250 mm, diameter of exit pupil 4 mm, spacing of exit pupil 32 mm, front working length 683.9 mm. EFFECT: enhanced quality of picture with simultaneous increase of outlying of exit pupil with growth of value of linear field. 8 dwg