THORLABS LDM21, User Manual

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LDM21 Chapter 4: Operation
TTN013394-D02 Page 10
Chapter 4 Operation

With the laser mounted and the laser and temperature controller
connected, the LDM21 is ready to operate. Please refer to the operating
instructions for the laser and temperature controller for specific
operating instructions.

When operating at low temperatures in high humidity climates, the laser
mount may develop internal condensation. If this occurs, turn the laser
off, open the case, and allow the mount to dry off completely before re-
using.

When using a collimiating optic in the 1" threaded mount, the lens may
be positioned slightly laterally by loosening the four 2-56 screws on the
cover and shifting the cover plate manually.
4.1. Safe Operating Area
The LDM21 is intended to be operated at a fixed temperature set-point of 25 °C
but can be operated as low as 20 °C as long as the input power to the laser
diode (input current x LD voltage) does not exceed the values specified in the
Safe Operating Area curve as a function of ambient temperature. It is not
recommended that the LDM21 be driven with more than 600 mW of input power,
set to a temperature below 20 °C, or operated in an ambient temperature above
35 °C. Operating the LDM21 outside of the safe operating area will result in
thermal runaway of the cooling system which will damage the laser diode
mounted in the unit.
Additionally, the 2 W maximum cooling capacity includes the power dissipated by
the TEC element in addition to the input power of the laser diode. Careful
monitoring of the TEC power (TEC Current x TEC Voltage) along with the
parameters of the SOA curve will further ensure that the system is operating
within its capabilities.