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AssigneeMalvern Instruments Limited
InventorsDavid Michael Spriggs, Duncan Stephenson
Estimating the term…
Apparatus (100) for measuring particle size distribution by light scattering comprises a blue LED (102) and a 633 nm helium neon laser (104). Light output from the LED and laser is separately passed or reflected by a dichroic element (116) onto a common path through a sample cell (122) containing a sample, the particle size distribution of which is to be measured. Light scattered from the sample cell is detected by one or more detectors (112B-H). Light transmitted by the sample cell is detected by detectors 112A, 112J. Output signals from one or more of the detectors are passed to a computation unit (114) which calculates particle size distribution. A small percentage of light from the blue LED is reflected by the dichroic element to a detector (110). Similarly, a small percentage of light from the laser is passed by the dichroic element to the detector. Output signals from the detector are fed back to control units (106, 108) to stabilize the output power of the LED and laser.
Apparatus for measuring particle size distribution of a sample by light scattering, the apparatus comprising a first source for generating a first beam of light having a first wavelength and a second source for generating a second beam of light having a second wavelength, a dichroic element arranged to direct most of the power of the first and second beams onto a common path through the sample by transmission and reflection of the first and second beams respectively at the dichroic element, wherein the apparatus further comprises a first detector arranged to detect a portion of the first beam reflected by the dichroic element before it is directed onto the common path, and further comprising a control system for controlling the power of the first beam and wherein said control system is arranged to receive an output signal from the first detector and to adjust the power of the first beam in response thereto.
A method of measuring particle size distribution for a sample comprising the steps of:
Apparatus for measuring particle size distribution of a sample by light scattering, the apparatus comprising:
Dependencies are inferred from the claim text.