A Near-Infrared (NIR) Technique for Imaging Food Materials

摘要

The results of imaging experiments in food materials are presented, using near-infrared wavelengths. The technique uses a modulated source and a lock-in amplifier detection circuit to give a high sensitivity to changes in through-transmission signal levels. This is shown to lead to a set of images, whereby the internal content of vari-ous foods can he imaged. Examples are presented of the detection of foreign bodies, both metallic and nonnietallic, to illustrate the imaging performance.