help with first project

[numberonekiwi]

Hi I would like to build my first simple laser and have come across this little package

http://www.jaycar.co.nz/productView...d2=&pageNumber=&priceMin=&priceMax=&SUBCATID=


Although this would only be a practice build for me I would ultimately like to pull a diode from a DVD drive but have a few questions about this

1- It was mentioned on one of the how to extract the diode from a video but that clip stated it had to be from a RW drive (not just +r/-r) is there any reason for this (red vs IR)?

2- would the lens supplied in the above unit be ok to use with ~200mW(16x) dvd laser ?

3- Would I be right in assuming that 8x DVD is around 140mW and if so is this enough power to still pop balloons and light matches?

4- most important are all dvd Diodes the same size ? or fit the lens mentioned earlier


Many thanks from a newbie

**DDL EDIT: Fixed link**

 

[Greenie]

Until a Mod fixes the link here it is http://www.jaycar.co.nz

Their site seems to be down for me but i'll check back later to see if I can help you with your question.

 

[numberonekiwi]

ok thanks for that I know @ the moment I am having great difficulties with international sites bandwidths/speeds less than dial up must be in both directions

 

[o_DEATH_ANG3L_o]

That diode is only 10 mW. You will not be able to burn anything with it. :-/

 

[Things]

aaahhh yes, i have used a couple of those diodes! fun to play with, but no burning in them.

 

[numberonekiwi]

it was not my main intention with this diode to burn things but to get a little practice with the 'getting it all working without killing the diode'

The main thing I wanted to know is that pictures I have seen of higher power diodes from DVD drives look similar to the 10mW one and was wondering / actually hoping that I could just use the lens that comes with the 10mW and fit it straight to the DVD lens

I have ordered an asus DRW-1814BL to replace my liteon 8X drive which I will use (hopefully for this project) anyway I suppose it is all about try it and see if it works

 

[marianne]

it might be better to fit it into an appropriately sized aixiz module? and good luck

 

[JECS]

1- the main reason is that the rw drives have the most powerful lasers since they need to burn at quicker speeds. ir lasers are dangerous since you cant see the beam.

2- possibly? but you will need a housing that will provide cooling so an aixiz module would be a good thing to have because it will do that and it will have an adjustable lense

3- it will still pop balloons. probably just not as quick. all depends how you have things set up. (i have seen movies of 8x lasers popping balloons)

4- i dont think they are always the same size but they usually are. i think ive even heard about some people getting square diodes.

i never had a chance to test the lenses from the dvd burner but i dont think they will work in a pointer. pretty sure i saw something about them focusing the beam at very close range. which makes sense since they need to burn to a cd not even an inch away. which means that after that point the beam will start to unfocus and spread out.

 

[numberonekiwi]

I have just dissected the diodes out of my asus 8x DVD burner and the process was quite simple but one of the diodes had an extra piece on the top about 1.5~2.0 mm cube I assumed this was proberly the IR diode so applied power to it and it emitted a red light but not very bright I then applied power to the other Diode and a huge amount of red light came out So I think my assumptions were correct do some DVD burners use two red LDs or not?

 

[MarioMaster]

you were probably seeing the near IR from the cd diode, since it's probably got a decent output power you were probably seeing the IR light as it's not completely invisible

 

[numberonekiwi]

When I was testing the burning LD I was using 2x NiMH rechargeable AA batteries and got a reasonable amount of light took a while to get it focused but it did not seem to have any heat even shining it on my skin with a black dot from a marker pen I measured the current and the brightness dropped of significantly with around 30mA I thinks this was due to the voltage drop inside the DVM however when I put a 3rd battery 3.6v and a 1N5401 diode to drop the voltage to about 3.0v got around 90mA and again a fairly bright light couldn't measure heat as was holding other wires

 

[numberonekiwi]

Latest I tried through lack of burning power was with 3x aa batteries 3.6V and I had heat 10~15 sec on my hand with a black dot and the heat was quite alot and also burned tiny holes in a black plastic bag so YES finally I have a toy will post some pics when I can but I think I need a few more posts But I have one question if running @ 140mA and 3.7v will i fry this LD or is that a normal current ? or should I have like a small resistor in series ?
I am currently using the LD in the heat sink that was mounted in the DVD as it is a very similar size to an AA battery therefore fits a battery holder