... Diameter of Visual Field(mm):10×(18mm),16×(14.5mm),Adjustable Range of Pupil Distance(mm)50 ~ 82Adjustable Diopter-5D,+5DSlit ... )Continuously variable from 1mm to 10mmSlit Angle Slit Inclination 0 ~ 180°adjustbale 0-23 degreeLight Spot Diameter(mm),φ10, φ7 , φ5,φ3 ... ,φ1,φ0.2Filterheat absorption,grey,red free, cobalt blueIllumination bulb12V/50W halogen ...