I measured the ETMY oplev beam size at a couple different distances away from the HeNe by taking out the steering mirror and letting the light propagate a ways. I put the steering mirror back, aligned the oplev, and was able to relock the Yarm, so I think it's all back as it has been the last couple of weeks.
Now I need t o do some geometry and ray-tracing matrices to decide what focal length lens to buy, then we'll have a shiny new ETMY oplev. |