| 摘要 |
PURPOSE:To widen an observation range and to improve the efficiency of photodetection and the accuracy of measurement by disposing the optical fibers in a light emitting part so as to be enclosed by six pieces of the optical fibers in a photodetecting part and disposing the optical fibers in the photodetecting part so as to contact the another optical fibers in the light emitting part. CONSTITUTION:The optical fiber bundle to be inserted into powder is so disposed that the optical fibers 18' in a light emitting part are enclosed by six pieces of the optical fibers 18'' in a photodetecting part, and that the optical fibers 18'' in the photodetecting part are in contact with the another optical fibers in the light emitting part. Therefore the light emitting range of the fibers 18' and the photodetecting range of the fibers 18'' overlap as shown by the shaded parts in the figure and since virtually no blind zones are formed, the range of observation is widened and the efficiency of photodetection is improved. The ascending speed of bubbles and the sizes of the bubbles are measured from the varying intensities of the light reflected from particles and the bubbles by using such fibers, whereby the discrimination between the bubbles and the particles is made easy and the improvement in the accuracy of measurement is made possible. |
