1992 年 7 巻 2 号 p. 119-124
A new method to identify the shape and the size of fibrils of asbestos by the diffraction patterns of the laser beam from the fibrils has been developed. The diffraction patterns from the fibrils are identified with reference shapes in the Multiplexed Matched Spatial Filter. The locations of the autocorrelation peaks on the back focal plane of an inverse Fourier transform lens show the shape, size and position of the fibrils simultaneously and instantaneously. This method of the measurement of the shape, size and position of the small fibrils is examined theoretically and experimentally.