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The laser driver board can be used in conjunction
with the phase controller and
PSD boards in order to provide a fully functional derivative
spectroscopy measurement system.
A low-noise, high-quality laser driver module working in a constant
current configuration is used to provide a highly stable laser diode
drive current. Capable of providing 2A this module also comes with
current limit control, soft-start drive circuitry and input
modulation protection.
The current through the laser diode is controlled by a single 0 to
2volt signal which can be derived from an external source or more
usually from the phase controller board (analogue output). This
ensures that the measurement system is fully synchronised and that
maximum signal detection sensitivity can be achieved. A d.c or ramp
voltage can also be added to the modulation-input signal. This
signal input when used in conjunction with a reference channel
arrangement can provide feed back control of the measurement system
and keep the laser at the wavelength required.
In addition to the laser driver circuitry the board also contains a
very low noise dual rail power supply which, when used in a full
stack arrangement, is used to power the PSD board and provide a
suitable low noise power source for front end photodiode amplifiers.
Photodiode amplifiers and high precision
Peltier control modules are also available from AOS.
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