Green laser help?

[Georgy291]

cheers secretly i actually was going to do this to mod my green one to burn things, but im also doing it for the electronic desighn, im my self a 6th form student....next year hoping to do avionics in uni (for those who dont know....avionics is short for electronic systems on a aircraft) but my dad is a huge electronic engeneer so he is helping me out on this hugely

and i know its not linear at all with diodes, my dad has already given me a desighn for 90% efficient current source that will suply the laser diode with 250mA from any voltages ranging 3v to 32v, i just lost the circuit diagram...waiting for him to re draw it, but for those who are here im sure youd be interested to see it to. il post it today about 8ish


As for the shining in to planes, no chance at cruising since they are 15km in the air but by heathrow it would be just annoying, as modern planes are landed using ILS and pilot doesnt really do anything, so you would just annoy him

[SamanthaCarter]

It's not the current source you should be worried about. It's crystal efficiency. It's very easy to overheat and destroy the crystals. Happy learning ^^ Green lasers can be an expensive hobby, that's for sure...

[Whiternoise]

As for the shining in to planes, no chance at cruising since they are 15km in the air but by heathrow it would be just annoying, as modern planes are landed using ILS and pilot doesnt really do anything, so you would just annoy him

As far as i'm aware, yes you use ILS, but it's only a feedback system - so the pilot still has to set glide slopes and so on. Fact remains that you should not be shining lasers near airfields regardless of what technology the pilots use to land or take off. Heathrow actually poses a reasonable risk, there number of planes holding stack around london is pretty large, and those headings have to be controlled manually most of the time.

Take the Hudson incident last week, the pilot had to take control of the aircraft at about 1 mile, most green lasers can easily reach that. If it had happened at night, there could have been a serious issue. But just because there are automated processes doesn't mean that everything is magically safe. The main danger, as i said, is from things like helicopters which tend to fly at fairly low altitudes.

There's also the potential security risk. If you shine a laser at a plane, who's to know that it's just some rubbishrubbishrubbishrubbish with a laser pointer and not someone with a laser guided weapon?

I know it sounds pedantic and i'm sounding like a killjoy (don't get me wrong, i love my green laser ), but i'm planning on getting a PPL (and possibly going to go commercial) and currently fly gliders so i've had a fair amount of time in the air - the risk is very real.

[Georgy291]

I finnaly got the data for the power suply for the diodes, i seriously recoment stipping any electronics the curent laser comes, to the just diode its self, and replacing it with this, google this chip ZXLD1350

the overall efficiency goes up to about 90% off the electronics, thats 90% off the battery power going straght to the diode, also this keeps the diodes max brightness regardless off the states of battery. ie 100% brightness when batt is full, 100% when batt is half full, 100% just before batt runs out, i know amasing tehnology,

i used this driver to power my LED tourch and it does wonders, its either like i said on full brightness all the time or when batts die it just switches off and you know to replace them,

full spec sheet is

http://www.zetex.com/3.0/pdf/ZXLD1350.pdf

i dont think you need such a high electronics knoledge to work it out how it works but there are few complex formulae

SamanthaCarter thats something for you to look at, a chalenge for you to work out how it works

oh and btw my sole perpose of doing this is to make a cutting laser

[Georgy291]

sorry Whiternoise i have just noticed your post,

im not stupid to do that since i know its silly thing to do, and i also live no where near a big airport i live 200miles away from heathrow, im a rubbish place called swansea

[DataMatrix]

it first consists of a infared laser off 808nm then it has got a crystal thats green in colour and couses the 532nm light

You got ripped off. Infrared lasers without an IR filter are highly dangerous to your eyes!

[Georgy291]

i only payed £5 for it, i dont think thats a rip off?

[SamanthaCarter]

Ya, I paid about £25 for 5mw green laser back in the day. But yeah..


808 Diode - some sort of rare earth crystals i can't remember off the top of my head which shifts 808 to 1064 then the next crystal is frequency doubler to 532nm. Then after the Multiple Crystal Assembly... a small infrared filter, before being fed into a collimator lens to create a nice thin beam =)

Amazing how small the MCA is actually...like..as small as 1mm squared. Higher output models have larger more efficiency crystals. Talking PGL-3 150mw lasers and stuff.

As for the law-it's "pointers" which can't be <1mw technically. After that, they need to have safety switches and be classed as professional standard lasers...not hand held pointers.

But who cares =D As long as one is careful and not silly with them, they can be great fun. Burning through black insulation tape is very satisfying.