Alpes Lasers ECLK, Руководство пользователя

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3. Maintenance
The External Cavity Laser Kit is shipped assembled and aligned. The system is
highly sensitive to optical alignment and any manipulation of its opto-mechanical
components might lead to a suboptimal operation. In this case, or in the case of
any intentional reconfiguration, such as the installation of a new gain chip or a new
diffraction grating, it is essential to set up the system properly in order to produce a
well-performing laser action. The following sections describe the optical alignment
procedure.
The alignment leads to beam of a gaussian profile collimated along the z-axis of
the system (see Fig. 3.1). Figure 3.1 shows schematically the degrees of freedom
available on placing the components. To install a gain chip in the external cavity
system, complete the following steps:
1. Install the new chip-on-carrier on the laser module.
2. Connect the QCL wires to the pulsed driver (pay attention to polarity).
3. Install the front and back lenses.
4. Remove the rotation stage from the grating module.
5. Turn on the temperature controller and the laser driver.
6. Adjust the back lens to collimate the beam using an IR detector or camera.
7. Put the rotation stage back on the grating module.
8. Monitor power of the front facet with an IR camera.
9. Optimize the grating tilt using the goniometer and the back lens focal distance
using the focus adjuster to minimize laser threshold.
10. Adjust the front lens to collimate the output beam.
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