User:Andy Maloney/Notebook/Lab Notebook of Andy Maloney/2009/06/09/Please sir, may I have some more laser?

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So below is the data for the LD over a 90 minute period. As you can see, the light shifts upwards over some time. I have no clue as to why it would do this.

Fiber update

So I was able to do a better job of aligning the fiber to the output of the cylindrical lenses. I was able to get a maximum power output of 415 mW. I start with about 700 mW and considering that I go through 11 elements, I think this is pretty good. Also, I believe this will be more than enough light to work for tweezing but I'm not sure.

It occurred to me that I have no clue as to where the telescope should go and why it should go there. The output from the collimating lenses gives a beam that is 10 mm in diameter which is close to the goal of 12.7 mm so I think a 1:1 telescope will work fine. I can make it larger but, we don't have the lenses to do that. But, I want to know where it should go and why it should go there before I set it up.

We should try to tweeze some beads tomorrow. And yes, I'm totally ignoring what I stated above. I still need to look into it.

Steve Koch 00:09, 10 June 2009 (EDT): Tweezing sounds great! I don't understand that laser drift either. If necessary, I think Evan bought another power stabilizer that we could try to use. Hopefully you got the email that I sent you with the Neuman & Block review. The telescope location is determined by: (a) mapping the first telescope lens onto the back aperture (so the beam doesn't move but only tilts) and (b) so you can reach the xyz stage with your hand conveniently while operating the tweezers. I forget that you weren't here during any of our OT discussions in the past. Larry & Ant know a ton about it, and Larry wrote up some really great summary pages on the private wiki. I suppose those should be sanitized and transferred over to the public now?

Update

Ha! Sanitized. At any rate, I successfully created a cannon tonight. This is due to my unfamiliarity with trying to get the condenser and objective to work properly so that you get a diffraction limited beam to tweeze with and at the same time be able to see what is going on. I guess someone can show me what's up with this later.

When you go to attach the fiber to the collimating lenses, you need to take care that the fiber is centered in the housing. Otherwise, you get a funky beam out.

Finally, we may need to look into better optics for the steering lenses and getting some more mechanics to make our lives easier.

How in the world did you guys get it to work previously? I will note finally that there is enough power in the beam to be able to visualize it through the goggles in the microscope. And those things are ND 5+!

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