LuxaScope Rechargeable Ophthalmoscope LED 3.7 V Whitedirect ophthalmoscope in pocket size correction values: + 20 bis 20 D ( 1 2 3 4 6 8 10 15 20 D) 5 different apertures: Fixation cross, large circle, small circle, semicircle, green filter illumination: LED illumination can be dimmed for an individual glare free brightness automatic switchoff after 3 minutes life expectancy of LEDs: approx. 50. 000 hours by constant current drive colour temperature: approx. 4. 200 K optimized design of head two