THORLABS PICO D, User Manual

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Obtain fast step response with short settling times when moving between fixed
wavelengths (“random access” tuning).
Minimize errors in position due to external forces ( i.e . vibrations, magnetic
fields)
The control system also monitors the optical output power in order to maintain a
constant optical output power throughout the tuning-range of PICO D. Using an ana-
log control port the user can set the optical output power.
The laser chip and the laser cavity are kept at constant temperature using a closed
loop thermo electrical cooler.
The inner metal casing functions as a body for the attachment of the different mod-
ules, such as fiber coupling-, laser unit, and sensor-mechanics. The outer casing is
made of metal and a layer of thermal isolating material. Furthermore there is a mag-
netic shield, made of a high permeability material, for preventing external magnetic
fields to interfere with the motor coils.
All lasers, and especially lasers having a resonator cavities defined by mechanical
tolerances, are delicate precision instruments and they must be handled accordingly.
PICO D is designed to withstand “normal” transportation and “normal” operation con-
ditions. Designer’s Guide
2.4 Mechanical interface
The PICO D is confined to a volume of maximum: 49 mm
×
93 mm
×
260 mm (W
×
H
×
L) [49 mm
×
93 mm
×
274.1 mm if the locking mechanism belonging to the sig-
nal connector is included). The PICO D front panels, having bulkhead and pigtail op-
tical output respectively, are shown in Figure 2–3, and the side-view of PICO D is
shown in Figure 2–4.