Viasho 4W 532nm Laser System Review!

[Laser Ben]

Alright guys, I just tested the beam, measured 2.2mm at the aperture and a almost exactly 25mm at 50 feet. This calculates out to a divergence of 1.496mRad. Very nice beam for a laser of this size/power! It is very round and runs in TEM00 mode for the time I have observed it.

Modulation to come next!

[Simon]

Ben,

How much is it ?

[aijii]

Yeah, test the modulation.

[Laser Ben]

Okay, modulation results! All tests are on TTL+ input (friend still has my function generator ). All inputs are 5V square wave at full power. Laser was sent into an integrating sphere with an avalanche photodiode and measured on a scope. In some of the pictures, there is the modulation input shown as input B. It shows as 50V/Div, but it was set on 10:1 scale so it is really 5V/Div.

[ElektroFreak]

Not bad at all!.. is it possible to use some other waveforms to observe linearity while ramping up to 5V over time rather than instantaneous TTL type stuff?

EDIT nvm.. just saw the part about the function generator..

[tocket]

Potential is not a very good unit for measuring radiant power. I'd convert it into something that actually makes sense (W).

[Laser Ben]

I don't have a sensor that can measure 0-5W full scale at very high speeds. This is about as linear as you are going to get, plus, it is only to see how the output rises and falls. If you want power measurements, go look on the first page.

[tocket]

How about calibrating the photodiode you're using now against another power meter? Once you have made the power-response curve you can easily convert between the two.