Chapter One: Introduction
© 2018 Cutting Edge Optronics, Inc.
6
Patara I and II Laser User Manual
Optics Subsystem
The optical subsystem consists of an optical assembly on a Northrop Grumman
industrial laser optics bench.
Electronic Subsystem
The electronic subsystem consists of a 4U sized eDrive with an internal TEC
controller (see
eDrive User Manual
[CEO-UMAN-0001] for details). Refer to
Chapter 4: Installation and Operation
to setup and operate the eDrive with the
Patara laser. Contact a Northrop Grumman service engineer for assistance.
Operation at reduced power requires that two settings be adjusted in the eDrive:
the Q-switch power, and Iset, the drive current level. The laser shipment includes
the ATP Test Report Data Summary that provides the values necessary to achieve
the full, 9 W, 5 W, and 2 W power conditions.
The temperature of the second harmonic generation (SHG) crystal for phase
matching is crucial to determining the performance of the Patara laser. It is set
and controlled by a TEC controller inside the eDrive. Refer to the
Check the
eDrive
section of this manual in
Chapter 4: Installation and Operation
for TEC
Controller settings.
Thermal Control Subsystem
Thermal control and heat removal from the laser transmitter is accomplished by
the chiller. The laser’s integral flow switch will interrupt drive current to the
amplifier module and power to the Q-switch should the flow rate fall below 1
gpm (3.8 lpm). Flow direction is labeled on the laser optics housing below the
coupler ports. Please observe the flow direction at all times.
The thermal control system must be capable of maintaining the temperature set
point to ±0.1 °C with a flow rate of 1.5 gpm (5.7 lpm). An input pressure of
approximately 49 psi is required at the laser housing. Chiller pressure may be
several psi higher if additional filtering, flow metering, fittings, and long runs of
coolant tubing are used.
Coolant used in the system must be compatible with the materials used in the
internal coolant lines of the laser. Tap or deionized water must be avoided
because of corrosion and mineral deposits. Northrop Grumman can supply an
approved coolant for this application.
