I am setting up a 4th harmonic generator for a Q-switched Nd:Yag laser that will already have the second harmonic generator in place. I need to know how to orient the KDP crystal with respect to the incident laser beam and at what temperature I should set its oven to. I am hoping there is a laser jock who can make quick work of these questions.
The KDP crystal has a graphite arrow on the top that points to one face and on the near side there is a graphite arrow pointing down.
The second harmonic generator is already installed on the laser, with a crystal tilt dial on the top. A third harmonic generator is also shown in the picture but will not be used at the same time as the 4th harmonic generator.
The simple scheme of the 4th harmonic (and 266 nm separating optics) is shown below.
