| 摘要 |
PURPOSE:To separate different kinds of laser beams having different wavelengths from each other with high accuracy by irradiating a fruit with a mixed laser beam composed of the different kinds of laser beams and receiving and detecting reflected light and transmitted light separated. CONSTITUTION:A mixed laser beam composed of different kinds of laser beams having different wavelengths and projected upon a fruit is made incident on an interference filter 1a after passing through the fruit. Since the filter 1a high- low reflects light when the incident angle is 45 deg. depending the wavelengths, the filter 1a reflects a first laser beam, but transmits second and third laser beams. Similarly, an interference filter 2a reflects the second laser beam, but transmits the third laser beam. A third interference filter absorbs partly reflected second laser beam at a trap 23, but transmits the first and third laser beams. A first colored glass filter absorbs the partly transmitted third laser beams at a trap 24, but transmits the first laser beam. A second colored glass filter absorbs partly reflected third laser beam at a trap 25, but transmits the second laser beam. Therefore, first, second, and third photodetectors respectively receive and detect the third, first, and second laser beams. |
