Randomly-polarized laser : how bad is it ?

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Randomly-polarized laser : how bad is it ?

Post by thycore » Sat Sep 30, 2017 2:05 am

Hia !

In my reading of the wonderful book Practical Holography, I figured that my laser was, in fact, randomly polarized (Uniphase 1125).

Question : how bad is it ?

- It will not be easy to use the brewster angle to avoid unnecessary reflexion on the glass plate (= half of power lost ), so, my 15mw laser becomes 7mw at some point ?
- It will have no impact on coherence length : polarized or not, I can make holograms of the same depth ?
- Is the "rotation of the polarization" slow or fast ? is it like the laser "chooses a random polarization and keeps it during the session" or is it like "it changes all the time, like every seconds or so ?"

Thanks again for your great support !

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Re: Randomly-polarized laser : how bad is it ?

Post by admin_jsfisher » Tue Oct 03, 2017 6:59 pm

Have a look at Sam's Laser FAQ. Search for "Unrandomizing the Polarization of a Randomly Polarized HeNe Tube".

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Re: Randomly-polarized laser : how bad is it ?

Post by 142laser » Mon Jul 09, 2018 6:16 pm

An 1125 is a 5 mW laser, healthy ones do 7.5 mW so they put 15 on the danger label. It is probably doing 6-7 mW. Phil

PS Sam and I have many, many HeNe's of all powers.

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