Beckman Coulter LS 13 320, User Manual

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PN B05577AC xxiv
LS 13 320 Introduction
Fourier Optics
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Micro Liquid Module (MLM)
In addition, an AutoPrep Station can be used in conjunction with the ALM.
The LS 13 320 incorporates Beckman Coulter's patented PIDS (Polarization Intensity Differential
Scattering) technology to provide a dynamic range of 0.017 µm to 2000 µm.
Figure 2 shows the PIDS
detectors.
Figure 2 PIDS Detectors
The LS 13 320 is designed to be fully compliant with the ISO standard covering particle sizing by the
laser scattering method (ISO 13320-1 Particle size analysis - Laser scattering methods - Part 1:
General principles).
The LS 13 320 includes a sophisticated software package with a multi-component Standard
Operating Procedure (SOP). This multi-component Standard Operating Procedure (SOP) assists
operators by ensuring that analyses are the same run-after-run.
Every element of the analysis, from method set-up to the final printout, can be locked into a user-
definable SOP. The SOP routine is divided into two distinct components; an SOM (Standard
Operating Method) and a Preference (.prf) file. The SOM includes all aspects of the analysis relating
to the instrument settings. The Preference file (.prf) includes choices relating to data presentation
and output formats.
Fourier Optics
Measuring Moving Particles
The LS 13 320 determines particle size distributions by measuring the pattern of light scattered by
the particles in the sample. This pattern of scattered light is often called a scattering pattern or
scattering function. More specifically, a scattering pattern is formed by light intensity as a function
of scattering angle. Each particle's scattering pattern is characteristic of its size. The pattern
measured by the LS 13 320 is the sum of the patterns scattered by each constituent particle in the
sample.