Alpes Lasers ECLK, Руководство пользователя

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Chapter 3: Maintenance
available four M2.5 screws.
Figure 3.4: S-2 pulsed driver. Connect QCL wires to screw teminals 4 and 7 as
indicated.
Make sure the encapsulated temperature sensor is well in its socket. Set up the
TC-3 temperature controller to ’4 wire RTD’, enable the connection and let the tem-
perature stabilize. Notice that in an unpurged environment, the minimal operation
temperature is limited by the dew point to about
17
◦
C
1
. Lower temperature may lead
to condensation on the gain chip and cause damages. In a purged environment, the
minimal operation temperature is given by the power consumption of gain chip and is
typically about
−
30
◦
C. Set the TEC current limit to
≤
5 A.
3.3 Back lens alignment
Place the back lens as shown in Fig. 3.5. The back lens is mounted in a holder
attached by two M3 screws to the focus adjuster flexure mechanism; this position is
fixed and does not allow any movement. The adjuster is attached via an adapter plate
to the heatsink assembly using two pairs of M3 screws and spring washers. There
is a quite large freedom in positioning the adjuster with respect to the adapter plate
which allows the lens alignment in the xz-plane. Do not tighten the screws completely
at this moment.
A coarse geometrical alignment of the back lens follows. The adjuster knob is tight-
ened in the middle of the allowed moving range. In the z-axis, the lens holder is
positioned as close as possible to the gain chip. Notice, that the shape of the lens
holder prevents any direct contact between the laser facet and the surface of the lens.
In the x-axis, the lens holder is shifted such, that the nylon-tip screw holding the lens
lies in the same plane as the gain chip. In the y-axis, by tightening the adjuster screws,
the center of lens is aligned with the laser facet. The final position is shown in Fig. 3.5
(left). Fasten the screws tightly to ensure that they do not move when manipulating
1
depending on meteorological conditions
20 ECLK user’s manual v1.0.6