Photochromic Lens Tester w/ LED Light Pad The photochromic lens tester with LED technology quickly demonstrates the photochromic properties of a lens. – Place the lens onto the lower surface under the UV LED lamps. The lens will darken in approx. 10 sec. The UV LED light does not alter the lens’ photochromic properties. – Place the lens onto the upper light pad to check the color intensity. The white LED light simulates sunlight and will show the color shade of a sun lens in a realistic way. It avoids color alteration caused by artificial lights. Power supply: 100V (12V 2 with transformer) Dimensions: 220x145x210 mm. Weight: 0.80 kg.