Principal Investigator: Albert McSweeney (Georgia Institute of Technology)
Sponsor: GWRI
Start Date: 1970-07-01; Completion Date: 1971-06-30;
Keywords:
Description:
Use of optical transformation techniques for measuring sediment particle size distributions has been investigated. An optical Fourier transformation system was set up in conjunction with a bundle of fiberoptic light-pipes connected to an array of photodetectors for analyzing the transforms of samples.
A simple analysis of two of the seven information channels of the fiber-optic bundle was performed as a test. The measurements of intensity due to two known monodisperse samples were used to generate a 2 x 2 matrix of weight functions. This matrix was small enough to be easily calculated and provided an example for calculating the larger transformation matrix required for using all seven channels. The matrix of weight functions was then used to transform the measured intensity from a mixture where one of the two particle sizes present was significantly different from either of the sizes used to determine the matrix. Quantitative results show that while the system could not distinguish between 160 ~m and 187 ~m diameter particles, it did discriminate well between 267 ~m and 321 ~m diameter particles. The implied size resolution and accuracy are encouraging and both characteristics are expected to improve as more fiber-optic channels are used.