Aethalometer

Patent · Mon Jan 01 00:00:00 EST 1990

OSTI ID:867244

Hansen, Anthony D ^[1]

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1. Berkeley, CA

An improved aethalometer (10) having a single light source (18) and a single light detector (20) and two light paths (21, 22) from the light source (18) to the light detector (20). A quartz fiber filter (13) is inserted in the device, the filter (13) having a collection area (23) in one light path (21) and a reference area (24) in the other light path (22). A gas flow path (46) through the aethalometer housing (11) allows ambient air to flow through the collection area (23) of the filter (13) so that aerosol particles can be collected on the filter. A rotating disk (31) with an opening (33) therethrough allows light for the light source (18) to pass alternately through the two light paths (21, 22). The voltage output of the detector (20) is applied to a VCO (52) and the VCO pulses for light transmission separately through the two light paths (21, 22 ) are counted and compared to determine the absorption coefficient of the collected aerosol particles.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• DOE Contract Number: AC03-76SF00098
• Assignee: United States of America as represented by United States (Washington, DC)
• Patent Number(s): US 4893934
• OSTI ID: 867244
• Country of Publication: United States
• Language: English

Related Subjects

aethalometer
improved
10
single
light
source
18
detector
20
paths
21
22
quartz
fiber
filter
13
inserted
device
collection
23
path
reference
24
gas
flow
46
housing
11
allows
ambient
air
aerosol
particles
collected
rotating
disk
31
33
therethrough
pass
alternately
voltage
output
applied
vco
52
pulses
transmission
separately
counted
compared
determine
absorption
coefficient
single light
light transmission
aerosol particle
aerosol particles
voltage output
ambient air
gas flow
light source
flow path
absorption coefficient
light detector
light paths
rotating disk
light path
quartz fiber
fiber filter
/356/