年間 12 号発行
ISSN 印刷: 1044-5110
ISSN オンライン: 1936-2684
Indexed in
CORRECTING MALVERN PARTICLE SIZE MEASUREMENTS FOR PHASE DISTORTION
要約
The two effects of phase distortion on particle size measurements made with a Malvern spray analyzer are identified as beam spread and a shift of the Airy pattern extrema to higher spatial frequencies. Beam spread is shown to be present regardless of the laser beam coherence length (lc), while the Airy pattern shift occurs when the size of the particle being sampled exceeds lc. A correction scheme that removes the effects of phase distortion whenever possible is outlined, and then evaluated by comparing phase-distorted particle size information with its undistorted counterpart. The enhanced agreement indicates that the proposed technique successfully removes the effects of phase distortion whenever possible. Finally, guidelines are provided for determining when phase distortion is present, and when the correction scheme can be applied.