Powering up a blue laser diode to 500mW 🙂
Note how it acts like a poor LED until 150mA, at which point the laser process fires 🔥

The 505B is an accurate, adjustable current source which allows for external modulation input.

It’s designed for low-noise (<1.5uA RMS) and it has a photo diode input, so with a calibrated light sensor, you can achieve constant power regulation.

Last but not least: it’s designed for maximum safety with two interlock circuits, one with a physical key.
Its internal design has a complex redundant output circuit, which ensures that the laser will NEVER illuminate unintended and it will NEVER exceed the chosen power setting.

A fancy current source indeed, a laboratory grade instrument 🙂

This video was shot wearing the appropriate safety glasses, be VERY CAREFUL when experimenting with lasers. Even a short duration reflection at this power level WILL damage your vision 🚨‼️

#electronicsengineering #electronics #physics #stem #laserfun #funwithlasers #ee #testandmeasurement

Whipped up a rubber band gun design in #Inkscape tonight, redesigning it as I run the first #LaserCut (hence the messy trigger). #FunWithLasers... Here's my laser cutter tracing out the design. The trigger mechanism needs a lot of work...

I found a small speaker and attached a square of reflector tape onto the dome.

Using the #CuteGen™️ I sent 1Vpp, 40Hz, to the speaker. No sound, which really isn’t a surprise because it hardly has any response at such low frequencies.

On the scope however, a funny curve appeared 😃

The top sine wave is the speaker drive signal, the lower yellow trace is the output from the laser amplifier (see my other post, building the circuit).
There’s a clear marking at the top and bottom of the sine wave. Between them, a sawtooth-like response. Each of the sawtooth peaks means the speaker surface moved a whole wavelength, in this case 650nm. 4-5 of those means that the speaker moves about 3um (micro meter) in each direction.
Not much 😳🤯

No wonder there’s no audible sound 👌🏻

It took a while for me to adjust it all to produce this measurement. But it does work 😎

#physics #stemeducation #stem #electronics #electronicsengineering #testandmeasurement #uni-t #rohdeschwarz #laser #funwithlasers

Saturday morning was a quick session at the new Creative Dunblane makerspace producing some Christmas decorations for a food bank Reverse Santa gift event #funwithlasers