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'''5/20/2014'''
Generating the (probable) 633 seems repeatable. David found it yesterday morning without having to realign the 780 to the 1064. He lost it later in the day, but was able to realign things and find it again. It seems brighter than ever. (He turned up the 780 tapered amp some.)
David coupled the beam that goes through the dichroic through a multimode fiber, and when the modulation is on, you can see some modulation in frequency in the light that it is transmitted. (It's not really flashing in the sense that it never goes to low brightness; the intensity definitely fluctuates visibly, though.) We can see this by eye, but we are still unable to detect it with the power meter or OSA.
We borrowed a filter centered at 630nm from John Boffard from CC Lin's group, and with that filter in front of the fiber coupler, the flashing through the fiber is more pronounced. The flashing light seems to be a larger fraction of the light, and the constant background seems to be cut down.
Looking at the spectrum analyzer, it seems that the "other red" we saw on 5/16 was probably ASE from the 780 tapered amplifier that has a wavelength outside of the range of the notch of the 780 notch filters.
'''5/16/2014'''
--seemed to correspond with the turning on and off of the modulation RF
It was a bit confusing, though, because in addition to the (probable) 633 that has the above characteristics, you can still see other red light coming from the prism. This other red light is constant in intensity, in contrast to the 633. I'm not sure exactly what is from, but it must be from the 785 beam. Maybe it is diffuse scattered light from the reflections of the (small amount of) 785 that reaches the prism. At its best, the 633 was seen to be at least as bright as this other constant beam, if not brighter. The 633 seemed to be coming from the same location on the prism as this other beam, though it was visible when the prism was viewed at a slightly different angle.
We initially overlapped the transmitted 785 (through the dichroic) and the generated 807 that also is transmitted through the dichroic. We did this with the Newport camera.
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