Abstract: A method and system for measuring a refractive index of a particle sample by using a polarization difference of scattered light distribution. The method comprises: acquiring a vertically polarized scattered light energy distribution E? and a horizontally polarized scattered light energy distribution E?, and calculating a scattered light energy distribution polarization difference Ed; according to Mie theory, calculating a vertically polarized scattered light energy matrix (aa) and a scattered light polarization difference matrix (bb) with k×l dimensions under a supposed refractive index value of n(i); calculating a particle size distribution W(i) of a measured particle; acquiring a polarization difference of scattered light distribution (cc); calculating a RMS error ?(j) of Ed and (cc); changing the refractive index value; and repeating the process over and over until finding a refractive index value with the smallest RMS error, wherein the refractive index is the true refractive index of the particle sample.

Abstract: A method and system for measuring a refractive index of a particle sample by using a polarization difference of scattered light distribution. The method comprises: acquiring a vertically polarized scattered light energy distribution E? and a horizontally polarized scattered light energy distribution E?, and calculating a scattered light energy distribution polarization difference Ed; according to Mie theory, calculating a vertically polarized scattered light energy matrix (aa) and a scattered light polarization difference matrix (bb) with k×? dimensions under a supposed refractive index value of n(i); calculating a particle size distribution W(i) of a measured particle; acquiring a polarization difference of scattered light distribution (cc); calculating a RMS error ?(i) of Ed and (cc); changing the refractive index value; and repeating the process over and over until finding a refractive index value with the smallest RMS error, wherein the refractive index is the true refractive index of the particle sample.

Abstract: A laser particle size analyzer with a liquid sheath flow measuring cell comprises a measuring cell which comprises a particle flow leading-in cavity (3000), a medium flow leading-in cavity (1000) and a measuring glass cavity (2000), wherein the medium flow leading-in cavity (1000) is connected to an upper portion of the measuring glass cavity (2000); the medium flow leading-in cavity (1000) is annularly arranged at a periphery of the particle flow leading-in cavity (3000), and a gap (607) is formed between the medium flow leading-in cavity (1000) and the particle flow leading-in cavity (3000); a medium flow (70) flows into the measuring glass cavity (2000) from the gap (607), and a particle flow (60) flows into the measuring glass cavity (2000) from the particle flow leading-in cavity (3000). The laser particle size analyzer achieves technical effects of long service life, simple operation and good use effect of the measuring cell.

Abstract: The disclosure provides a stereoscopic vision three dimensional measurement method and system calculating a laser speckle as a texture. The measurement method includes that: a forming process of a laser speckle is simulated first, and calculation is performed to obtain a digitized laser speckle diagram, then the laser speckle diagram is outputted onto a film or a photographic dry plate, the laser speckle diagram on the film or the photographic dry plate is projected onto a surface of a measured object subsequently; a left view and a right view of the measured object are acquired finally, and all matching points corresponding to each other are found in the left view and the right view, and then a three dimensional point cloud of the surface of the measured object is reconstructed.

Abstract: The disclosure provides a stereoscopic vision three dimensional measurement method and system calculating a laser speckle as a texture. The measurement method includes that: a forming process of a laser speckle is simulated first, and calculation is performed to obtain a digitized laser speckle diagram, then the laser speckle diagram is outputted onto a film or a photographic dry plate, the laser speckle diagram on the film or the photographic dry plate is projected onto a surface of a measured object subsequently; a left view and a right view of the measured object are acquired finally, and all matching points corresponding to each other are found in the left view and the right view, and then a three dimensional point cloud of the surface of the measured object is reconstructed.