Light scattering apparatus and method for determining radiation exposure to plastic detectors

Patent · Mon Dec 31 23:00:00 EST 2001

OSTI ID:874862

Hermes, Robert E ^[1]

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1. White Rock, NM

An improved system and method of analyzing cumulative radiation exposure registered as pits on track etch foils of radiation dosimeters. The light scattering apparatus and method of the present invention increases the speed of analysis while it also provides the ability to analyze exposure levels beyond that which may be properly measured with conventional techniques. Dosimeters often contain small plastic sheets that register accumulated damage when exposed to a radiation source. When the plastic sheet from the dosimeter is chemically etched, a track etch foil is produced wherein pits or holes are created in the plastic. The number of these pits, or holes, per unit of area (pit density) correspond to the amount of cumulative radiation exposure which is being optically measured by the apparatus. To measure the cumulative radiation exposure of a track etch foil a high intensity collimated beam is passed through foil such that the pits and holes within the track etch foil cause a portion of the impinging light beam to become scattered upon exit. The scattered light is focused with a lens, while the primary collimated light beam (unscattered light) is blocked. The scattered light is focused by the lens onto an optical detector capable of registering the optical power of the scattered light which corresponds to the cumulative radiation to which the track etch foil has been exposed.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM
• DOE Contract Number: W-7405-ENG-36
• Assignee: The Regents of the University of California (Oakland, CA)
• Patent Number(s): US 6476910
• OSTI ID: 874862
• Country of Publication: United States
• Language: English

Related Subjects

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ability
accumulated
amount
analysis
analyze
analyzing
apparatus
beam
blocked
capable
chemically
collimated
collimated beam
contain
conventional
corresponds
created
cumulative
damage
density
detector
detectors
determining
dosimeter
dosimeters
etch
etched
exit
exposed
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focused
foil
foils
holes
impinging
improved
increases
intensity
lens
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light
light beam
measure
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optical
optically
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pit
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plastic
portion
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primary
produced
properly
provides
radiation
radiation dosimeter
radiation source
register
registered
registering
scattered
scattering
sheet
sheets
source
speed
techniques
track
track etch
unit
unscattered