FACILITY MEASURING CHARACTERISTICS OF TRANSPARENT IN HOMOGENEITIES Russian patent published in 2003 - IPC

FIELD: optical shadow devices recording pulsation of gradient of refractive index of examined optically clear medium. SUBSTANCE: objective of invention consists in compensation for vibration noise under conditions of minimal flow noise and in measurement of average speed of flow of medium in examined space. This objective is achieved by installation of photodetector overlapping field of vision and incorporating several photodiodes in plane of image of middle of examined space in shadow device. One photodiode placed in center presents rectangle with side ratio less than 0.02 which long side is parallel to edge of knife and other photodiodes are arranged in symmetry with central photodiode. Output of central photodiode and summary output of all photodetectors are connected to subtracter and output of subtracter is linked to input of signal processing device. Outputs of photodetectors spaced apart most of all in direction perpendicular to edge of knife are connected to corresponding correlators which outputs are connected to input of facility measuring average speed of flow. EFFECT: compensation for vibration noise, measurement of average speed of low of medium. 1 dwg