OPTIC DEVICE FOR DETECTION OF CHARACTERISTICS OF PARTICLES IN MOVEMENT

摘要

The device uses the Doppler effect principle of laser velocity measurement. It comprises optical emission and reception guides formed by optical integration techniques on a single substrate (12), preferably glass. The emission guides, connected to a light source (3) produce two mutually coherent beams (1, 2) whose inclination from one another (A) is such as to constitute interference fringes in a measurement region (P) external to the substrate. The reception guides transmit to a detection and processing circuit (11, 9) the light refracted by the passage of particles across the measurement region. The substrate (12) is mounted on a support (15) installed in the orifice of a wall (16) along which flows the fluid transporting the particles to be examined. The substrate (12) comprises a plane (17) that is in contact with the fluid. This device facilitates determining the speed, size and/or number of moving particles in a fluid being displaced along a wall (16).