Lighter Eyepiece Assembly：
EFL:25.1mm+/-0.5mm；
Exit pupil diameter≥14mm on axis；
Exit pupil distance：25mm；
Field of view ≥40°(for 17.5mm image format)
M.T.F at 30lp/mm≥86% on axis
Distortion：-5.5% (at semi-field angle of 20°)
Immersion:20 meters for not less than 2 hours
Weight≦ 50 grams
Lighter Objective Assembly：
EFL:25.1mm+/-0.5mm；
F-Number≤1.23；
Field of view ≥40°(for 17.5mm image format)
M. T.F at 70lp/mm≥43% on axis
Distortion：-4.7% (at semi-field angle of 20°)
Immersion:20 meters for not less than 2 hours
Weight≦41 grams
Eyepiece and Objective Assembly
Distortion：＜1%，+/-0.5% at semi-field angle of 20°；
Resolution：adapted to high resolution three generation image intensifier；
Magnification：1×
Diopter focus：+2 to -6
Field of view ≥40°；