Abstract: A semiconductor body is used by the present invention in the detection of ultraviolet radiation. An antireflection layer is on a portion of a surface of said body with electrical contacting means on the remaining portion of the body. A phosphor layer is on the antireflection layer. The phosphor layer is capable of converting the ultraviolet radiation into visible or near infrared radiation which can be detected by the semiconductor body. On the phosphor layer is a metallic film which is substantially transmissive to ultraviolet radiation and substantially reflective to visible or near infrared radiation. The converted radiation in the phosphor layer which strikes the metallic flow may therefore be directed toward the semiconductor body for detection.