OCULAR DATA INPUT SYSTEM Russian patent published in 2002 - IPC

FIELD: observation devices. SUBSTANCE: system designed to enter service information such as range to object measured by range finder to ocular has optically coupled display unit, projection system incorporating projection lens and matching subsystem, and ocular. Newly introduced in projection system is plane-parallel strip placed in front of or behind projection lens and tilted to optical axis of projection system. Equation solved is , where Δt is ocular astigmatism reduced to plane of objects coinciding with display unit; α₁ is correction factor; d is width of plane-parallel strip; n is refractive index of plane-parallel strip material; ε is angle of plane- parallel strip inclination to optical axis of projection system. At Δt>0 plane-parallel strip is tilted in sagittal section of projection system and at Δt<0 it is inclined in meridian section of projection system. EFFECT: improved quality of system image in data input to edge of field of vision due to ocular astigmatism correction. 5 dwg