Improvement of FD method to measure the distribution of particles’ sizes

The method to measure the distribution of particles.size based on FD principle has been applied for a long time.However its results are affected by the limitation of SSPD and the error of inversion method itself.In the paper,the effect of diffration image central framing,the characters of PSD and CCD response property are studied.Then two methods,i.e.the central framing by PSD and RGB equilibrium by CCD for the diffraction image receiving are put forward,which settle the problem of precision of central framing and determination of r and H and meanwhile escape the problem of peak value saturation by a CCD.Finally,a continual distribution I(H) is obtained and the distribution of particles.size n(D) is inverted accurately upon the Shifrin inversion in the measurement.