| 摘要 |
<p>A hand-held device for evaluating skin or hair condition which includes a housing, a hydration meter (12), and a plurality of light emitting diodes (LEDs) (14,15,16,18) The hydration meter is supported within the housing and has an external surface portion contactable against skin or hair to measure moisture content At least one of the LEDs both emits and absorbs light Advantageously the LEDs include a red, a blue, a green and two infrared wavelength light emitters</p> |
