Development of a device to measure human hair luster

Evaluating human hair luster is important in developing effective hair care products. Many methods of measuring human hair luster have been proposed, but most have major disadvantages: some require cutting the subject's hair, some utilize bulky equipment, and some take much time. A device that does not impose excessive burden on the subject and hair, but can easily and conveniently measure human hair luster, has not yet been developed. Overcoming the disadvantages of the traditional method, our new device can measure luster accurately without cutting the hair. Neither the subject's hairstyle nor its color influences the measurements. The device is small, and the time required for measurement is only 0.2 sec. The hair of 84 subjects was evaluated using this device, and there was a high correlation between the sensory score and the measurements obtained.