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Title: Paper area density measurement from forward transmitted scattered light

Abstract

A method whereby the average paper fiber area density (weight per unit area) can be directly calculated from the intensity of transmitted, scattered light at two different wavelengths, one being a non-absorpted wavelength. Also, the method makes it possible to derive the water percentage per fiber area density from a two-wavelength measurement. In the optical measuring technique optical transmitted intensity, for example, at 2.1 microns cellulose absorption line is measured and compared with another scattered, optical transmitted intensity reference in the nearby spectrum region, such as 1.68 microns, where there is no absorption. From the ratio of these two intensities, one can calculate the scattering absorption coefficient at 2.1 microns. This absorption coefficient at this wavelength is, then, experimentally correlated to the paper fiber area density. The water percentage per fiber area density can be derived from this two-wavelength measurement approach.

Inventors:
 [1]
  1. San Ramon, CA
Issue Date:
Research Org.:
Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
OSTI Identifier:
873717
Patent Number(s):
6229612
Assignee:
Regents of University of California (Oakland, CA)
Patent Classifications (CPCs):
G - PHYSICS G01 - MEASURING G01N - INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
Y - NEW / CROSS SECTIONAL TECHNOLOGIES Y10 - TECHNICAL SUBJECTS COVERED BY FORMER USPC Y10S - TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
DOE Contract Number:  
W-7405-ENG-48
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
paper; density; measurement; forward; transmitted; scattered; light; method; whereby; average; fiber; weight; unit; directly; calculated; intensity; wavelengths; non-absorpted; wavelength; makes; derive; water; percentage; two-wavelength; optical; measuring; technique; example; microns; cellulose; absorption; line; measured; compared; reference; nearby; spectrum; region; 68; ratio; intensities; calculate; scattering; coefficient; experimentally; correlated; derived; approach; density measurement; scattered light; transmitted intensity; absorption coefficient; absorption line; method whereby; /356/162/250/

Citation Formats

Koo, Jackson C. Paper area density measurement from forward transmitted scattered light. United States: N. p., 2001. Web.
Koo, Jackson C. Paper area density measurement from forward transmitted scattered light. United States.
Koo, Jackson C. Mon . "Paper area density measurement from forward transmitted scattered light". United States. https://www.osti.gov/servlets/purl/873717.
@article{osti_873717,
title = {Paper area density measurement from forward transmitted scattered light},
author = {Koo, Jackson C},
abstractNote = {A method whereby the average paper fiber area density (weight per unit area) can be directly calculated from the intensity of transmitted, scattered light at two different wavelengths, one being a non-absorpted wavelength. Also, the method makes it possible to derive the water percentage per fiber area density from a two-wavelength measurement. In the optical measuring technique optical transmitted intensity, for example, at 2.1 microns cellulose absorption line is measured and compared with another scattered, optical transmitted intensity reference in the nearby spectrum region, such as 1.68 microns, where there is no absorption. From the ratio of these two intensities, one can calculate the scattering absorption coefficient at 2.1 microns. This absorption coefficient at this wavelength is, then, experimentally correlated to the paper fiber area density. The water percentage per fiber area density can be derived from this two-wavelength measurement approach.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {2001},
month = {1}
}