The CZ-H52 from Keyence Corp. of America is a digital fiber optic UV sensor that detects fluorescent agents used in products and packaging materials. These include labels on plastic, metal and glass containers, tamper-evident packaging, protective coatings on soft drink and medicine containers, dyes, fluorescent paints and clear adhesives. An ultraviolet beam is emitted from the transmitter in the sensor head, and the receiver picks up the visible light reflected by fluorescent materials. Performance is not affected by background patterns or colors, and a sputtered gold coating on the receiver lens eliminates reflections from ambient and stray light. The sensor head measures 15 × 22 × 24 mm and has a detection range from 25 to 55 mm. The receiver detects fluorescent wavelengths from 425 to 550 nm.