THORLABS ITC4000 Series, Руководство по эксплуатации

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3 Operating the ITC4000 Series
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Temp. Protection Mode:
The temperature protection of the ITC4000 offers an internal temperature window monitoring
by the integrated TEC module. You can choose between:
None no action
Output enable the laser Output is switched off during the temperature is out of the selected
window and will be switched on automatically, if the temperature goes back
into the specified temperature window range
Protection the laser Output is switched off and can only be switched on by pressing the
"LD-ON" key again
Noise Reduction Filter
The noise reduction filter is a low pass that can be enabled to significantly decrease the laser
current noise.
Enabled The filter is enabled, LD current noise is reduced.
Disabled No filter.
Note
·
The noise reduction filter is available only in ITC4001, ITC4005 and ITC4005QCL.
·
Enabling the NR filter, the constant current modulation bandwidth decreases!
3.4 LD Source Setup
Setting the operating mode:
In the LD Source Setup menu you can change the operating mode of the ITC's laser current
driver between Constant Current mode and Constant Power mode. In Constant Current mode
an internal current loop to the laser will be closed. You can set the laser output current in
Ampere, read back and display the actual laser current. In Constant Current mode a preselec-
ted pulse regime enabled in section
QCW Pulse Settings may work together with the internal
laser current loop. In Constant Power mode a control loop will be closed via an external feed-
back source (current or voltage). A laser current dependent on the feedback value will be
driven. The optical output power can be set in Watts, when the response of the connected
feedback sensor is known and entered. Additionally you can set the corresponding feedback
current for photodiodes or the feedback voltage for voltage sensors like thermopiles.
Setting the laser current limit:
In the LD Source Setup menu, the laser diode current limit can be set. This limit is active in the
constant current mode and in the constant power mode, and protects the laser diode against
excessive laser current. This value can be set from 1 mA to 1.01 A (ITC4001), from 2 mA to
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