Patent ID: 7574252

Claim:
An apparatus for measuring fat thickness in a target body part of a person, the apparatus comprising: a single light emitter emitting near infrared rays; an inner reflector having a reflecting plane outside to reflect the near infrared rays emitted by the light emitter; an outer reflector surrounding the inner reflector and having a reflecting plane inside to reflect the near infrared rays emitted by the light emitter; a light receiver receiving light reflected from the target body part in response to the near infrared rays; and a calculator calculating the fat thickness in the target body part using the light received by the light receiver, wherein the calculator comprises: a ratio calculator calculating a ratio of intensity of the light received by the light receiver to intensity of the near infrared rays radiated at the target body part to obtain absorptance, and a thickness calculator calculating the fat thickness in the target body part using the calculated absorptance and a relationship between the absorptance and the fat thickness.