PURPOSE: To absorb infrared rays, ultraviolet rays, and visible range light other than near ultraviolet rays without providing any interference on an element surface nor spoiling its characteristics by providing a specific impregnated material layer on the surface of a plastic transparent body.
CONSTITUTION: The impregnated material layer 1a which transmits light with wavelength within a specific range as to visible rays and absorbs light outside the range is formed on the surface of a transparent body formed of plastic, e.g. lens 1, filter for absorbing infrared or ultraviolet rays, and condenser lens 3. This impregnated material layer 1a uses a coloring agent made of dispersed dye. This coloring agent has minimum transmissivity to, for example, about 520nm wavelength and cuts off ≥600nm long-wavelength light and ≤480nm wavelength light. The colored layer 1a on the surface of the optical element is formed by being impregnated with the coloring agent, so uniform light is transmitted regardless of the thickness of the element. Consequently, the optical element which transmits light rays within the visible range of specific wavelength and absorbs light with wavelength outside the specific range while maintaining the characteristics of the optical element is obtained.
NAMIKI KAZUO
TOMIJIMA YASUYUKI
| JPS4724831A |
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