New measurement technique that uses three near infrared diode lasers for non-destructive evaluation of sugar content in fruits

摘要

For non-destructive evaluation of sugar content in fruits, it has been proposed new measurement technique that usesthree near infrared diode lasers. The reflectance Ri at the wavelength λi is defined by the ratio of two diffuse light powersreaching the two receiving fibers that were positioned at the different distance from a light emitting fiber. The value γ =ln (Ri/Rk)/ln (Rj/Rk) reaches the value that doesn't approximately depend on optical path length. As a simulation result ofγ to a modeled apple, it was found that there are some combinations of three near-infrared wavelengths in which thecorrelation of γ and the sugar content of fruits raise. We actually evaluated the sugar content of apples by the use ofthree diode lasers 911nm, 936nm and 1055nm. As a result, it was confirmed that the measurement technique proposedhere was usefulness.