The Resonance GCSO2-1 is a UV-sensitive camera that compares images in two spectral bands to produce concentration maps of SO2
plumes. This method is based on differential optical absorption spectroscopy (DOAS) methodology for remote sensing of atmospheric
gases (Refs 1-12). GCSO2-1 has been under development since 2008 and the GC-SO2-1 is an elegant implementation of the method
that has several unique features. It employs a single back-thinned CMOS camera, which simultaneously captures two images of the target
plume in bands centered on 310 and 320 nm. Offsets due to changes between two imaging chips or moving filters are eliminated. The two
images are mirrored about the optical axis of the camera, which eliminates distortion and edge dimming. A complete calibration is
obtained by use of a PC-controlled SO2 gas cell wheel. Modeling and measurements show that the concentration maps from GCSO2-1
are highly specific to SO2 and are insensitive to changes in the spectrum of daylight due to solar elevation.
Features
- Produces quantitative images of SO2 in plumes from volcanoes and
stacks that can be used to determine SO2-mass fluxes in tonnes/day
- Captures simultaneous images at 310 and 320 NM
- Single UV lens for image stability
- Single detector eliminates drift between 2 detectors
- Distortion control with mirrors to cancel pincushion and barrel distortion
- Callibration using COSPEC SO2 cells
- Automatic dark subtraction
- Uses Ratio-of-Ratios technique for calibrated ppm-m 3D image
- Manual alignment adjustment through rear acces port
- Connects to control laptop computer via ethernet
- Powers off of external battery, DC, or AC outlet
Specifications
Shown with optional wireless camera
GCS02-1 Gas Camera integrated with scanning DOAS
Sakurajima, March 2016
Unzen, March 2016
Time-lapse of S02 measurements
S02 emission observed at Mount Aso, Japan September 2016
~20 ppm-m
Back-thinned CMOS
12-bit
4.8kg
284 x 182 x 188mm
63 lp/mm (center
12.5 x 16 degrees
LabVIEW based software
Sensitivity for SO2
Detection Method
ADC
Mass
Dimensions
MTF
Field of view
Software
Copyright Resonance Ltd., December 2011
143 Ferndale Drive North, Barrie, ON L4N 9V9 Tel: 705-733-3633 Fax: 705-733-1388 Email:sales@resonance.on.ca