BOREAL LASER GasFinder2, Operation Manual

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1.1
Boreal Laser Inc. GasFinder2 Operation Manual — System Description July 17th 2017
Boreal Laser’s patented (US Patent 5,637,872) TDL (Tunable Diode Laser) used in the
GasFinder2 measures gas concentration over an open path. The open path monitoring
system consists of an integrated transmitter/receiver and a remote, passive retrorefl ector
array. The remote retrorefl ector array is initially targeted by the operator using a two-axis
instrument mount assisted by a telescopic sight and an on-board visible red aiming laser.
The
GasFinder2 houses the laser diode source, the transmitter and receiver electronics,
the transmitter and microcomputer subsystems. The GasFinder2 is weather proof and
has connectors for 12VDC power input, and data I/O. A schematic representation of the
GasFinder2 system is shown below in fi gure 1.
The laser light emitted from the transceiver unit propagates through the atmosphere to the
retrorefl ector and returns to the
GasFinder2 , where it is focused onto a photodiode detector. A
portion of the laser beam is passed through an onboard reference cell to provide line centering.
The returning optical signals are converted into electrical waveforms, which the computer
processes to determine the actual concentration of gas along the optical path. The computed
gas concentration is then displayed on the rear panel of the instrument, and can be transmitted
to a computer where the data can be collected, stored, and graphically displayed.
It is possible to alter some of the parameters of the GasFinder2 remotely by using the GasViewOP
software or another terminal program. These can be conected with the GasFinder2 using
suitable cables or radio equipment supplied by Boreal Laser Inc.
Fig. 1 Schematic representation of GasFinder2
Section 1. System Description
Control
Electronics
12VDC input
Data I/O
Keypad
Display
Laser
Diode
Detector
Computer
Calibration
Reference
Cell
Shutter
Aiming
Laser
Signal
Processing
&
Display
Remote
Retroreflector
Aiming Scope