Mark S Koehler

US Patent:

43447090, Aug 17, 1982

Filed:

May 8, 1980

Appl. No.:

6/147854

Inventors:

Theodore Provder - Olmsted Falls OH
Richard M. Holsworth - Westlake OH
Mark E. Koehler - Middleburg Heights OH

Assignee:

SCM Corporation - Cleveland OH

International Classification:

G01N 2155
G01N 2147

US Classification:

356445

Abstract:

A method and apparatus for photogoniometric analysis of surfaces is disclosed. A photogoniometric instrument includes a light source (12) for providing a collimated beam of light illuminating a test surface (18). A light detector (20) is mounted for rotation about the point of intersection of the illuminating beam on the test surface. A motor (44) drives the detector through a range of reflectance angles, and a microcomputer (52) digitizes the detector output periodically, storing the digitized data words in its memory (68). These stored words define a photogoniometric curve (FIG. 2A) including a specular portion (FIG. 2D) and a nonspecular, or diffuse, portion (FIG. 2C). A host computer (62) receives the photogoniometric data from the microcomputer, deconvolutes the data into spectral and diffuse portions, and analyzes the two portions separately from one another. To accomplish this deconvolution, the host computer subtracts from the photogoniometric data the actual reflectance characteristic of a standard surface whose characteristic lacks the specular peak. This diffuse standard reflectance characteristic is stored in the host computer memory in the form of a mathematical equation which has been curve fitted to the actual reflectance characteristics of the diffused standard.

US Patent:

43110398, Jan 19, 1982

Filed:

Nov 14, 1979

Appl. No.:

6/093996

Inventors:

Mark E. Koehler - Middleburg Heights OH
Theodore Provder - Olmsted Falls OH
Richard A. Zander - Parma OH

International Classification:

G01N 1502

US Classification:

73 614

Abstract:

An apparatus is provided which is characterized by a motor, a transmission, e. g. , a continuously variable ratio friction transmission, and apparatus for interrupting power to the motor for a precise interval of time. A particular utilization of this device is for a photosedimentometer to enable more accurate determinations of particle size and size distribution.