摘要 |
<p>A particle imager and method for imaging particles on surfaces of substrates (19). A reflective suface (17) is scanned by a collimated light beam (57) and particles on the surface are detected by the scattered light caused by the particles. During a scan path (81) the intensity of the scattered light is measured forming intensity traces (91) and location addresses for the detected particles. Data from each scan path is stored in memory. A three-dimensional surface map (95) is formed from the data stored in memory. The intensity traces for a particle (71) when combined together in the surface map form an intensity profile (97, 99, 101) or signature of the particle. These signatures may then be compared to known particle signatures to determine characteristics of the detected particle.</p> |