The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 04, 1977
Filed:
Jan. 06, 1975
Alan L Wertheimer, North Wales, PA (US);
Leeds & Northrup Company, North Wales, PA (US);
Abstract
A rotating mask having three spatial filters is placed in the light path after a laser beam is passed through a sample having a collection of particles. The mask sequentially filters the light scattered by each particle to produce at a detector receiving the filtered light a response which is in accordance with the second, third and fourth power of the particle diameter. The detector integrates the response to all particles in the laser beam and the signal resulting from the integration of the response due to the individual filters is used to calculate statistical parameters. The mean of the area distribution is calculated as the third power response divided by the second power response. The mean of the volume distribution is calculated as the fourth power response divided by the third power response and the standard deviation of the area distribution as the square root of the product of the mean of the area distribution and the difference between the mean of the volume distribution and the mean of the area distribution.