Method and apparatus for particle analysis
AssigneeAmersham International plc
InventorMartin F. Finlan
Life of this patent
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Abstract
The apparatus comprises a cell 2 containing the sample 1 under investigation. Electromagnetic waves P1,P2 are applied from opposite directions and interfere with one another in the region of the cell to form a standing wave pattern 6. DUe to electrostriction effects the standing wave pattern causes particles within the sample to concentrate in certain areas in a pattern corresponding to that of the standing wave 6. This pattern of particle concentration forms a grating when seen by an input wave Pin of electromagnetic wave radiation and, provided conditions are correct, results in the generation of a phase conjugate wave Pout. Means (not shown) are provided for measuring the intensity of the phase conjugate wave Pout which gives a sensitive measure of the size of the particles suspended in the sample.
Claims18
Apparatus for particle analysis, said apparatus comprising a container made of electromagnetic radiation transparent material for containing a fluid sample to be analysed, means for setting up, within the sample, a stationary electromagnetic field comprising regions of high and low field intensity in a standing wave pattern in such a way as to establish within the sample a grating, means for applying to said grating an input wave of electromagnetic radiation in such a way as to cause said grating to generate a phase conjugate wave and means for measuring the intensity of said phase conjugate wave.
A method for the analysis of particles suspended within a fluid medium, said method comprising setting up, within a sample, a stationary electromagnetic field comprising regions of high and low field intensity in a standing wave pattern in such a way as to establish within the sample a grating, applying to said grating an input wave of electromagnetic radiation in such a way as to cause said grating to generate a phase conjugate wave, and measuring the intensity of said phase conjugate wave.
Dependencies are inferred from the claim text.