Technical Insight
White LEDs Debut in Operating Theatre (LED News)
Surgeons and scientists in Kyoto are collaborating on a head-mounted prototype white LED lighting system designed to provide directed illumination during surgical operations. The LEDs were mounted on simple lightweight goggles and made headlines in Japan recently following their use in a successful 2-hour forearm operation. Performing surgery under normal halogen-based ceiling lighting fixtures can leave the surgeon s head casting shadow and even hindering the light source, but the head-mounted LEDs allow lighting under all operation conditions. The system uses 56 white Nichia LEDs on each side of the lenses to provide up to 450 lm of illumination, without overheating either the doctor or patient. Power is supplied by a relatively light 7.2 V waist-mounted battery. Surgeon Junichi Shimada said that more sophisticated systems are currently being planned. One area of concern is the color rendering of the white emitters, which are based on standard 3 mm InGaN blue LEDs coated with yellow YAG phosphors. These 2-color devices do not correctly represent the red colors from skin, blood, tissue and internal organs. See .