Patent ID: 7400405
Filing Date: 2008-07-15
Classification: G01J,G01N

Abstract:
1. A handheld instrument for checking produce for the presence of pesticide residue, comprising: a housing having a grip which can be held in the hand and a barrel which can be pointed at the produce, an excitation source and an emission detector within the housing toward the rear of the barrel, a first group of optical fibers for directing light from the source down the barrel toward the produce to induce fluorescent emission from pesticide residue on the produce, a dichroic filter positioned toward the front of the barrel for transmitting the light toward the produce and reflecting emissions from pesticide residue on the produce, a second group of optical fibers for transmitting the reflected emissions down the barrel toward the detector, a first set of filters for selectively passing light of wavelengths which induce maximum fluorescent emission from different pesticides, a second set of filters for selectively passing emissions having spectral contents characteristic of the different pesticides, and means for selectively bringing the filters in the respective sets for one of the pesticides into registration with the excitation source and the emissions detector.