... lens (adjustable 20mm), optional 250mm apochromatic objective. 3, the primary mirror with a damping control system that moves the optical lens ... need to facilitate the dentist's surgery. 1, the primary mirror tilting binocular tube continuous range of> 90 °, the maximum turning ... , Φ10.4mm4, eyepiece 12.5 X / 18B5, large objective lens focal length: 250mm (optional 200,300,350,400)6, cold light source ...