First Build First Thread

[Tux]

I wouldn't call myself a complete noob when it comes to lasers, but I do require some assistance in building one from scratch. Just to be clear Im going to be a senior in high school and the top science class I have had is AP physics, so i will understand the basics pretty well.

Ok down to business, right now I have started to build a driver for a KEM 401 ACA PS3 blu-ray diode. I got the driver and ever thing hooked up on a bread board to one of the two laser diodes I extracted. I put the laser diode in one of my old green laser housings that was rated at 5mw. It wasn't working at first so i removed the voltage regulator from the circut and low and behold it worked, but something was wrong, the beam wasn't focused at all and after I put the lense over it the beam was to weak to escape.

The circutry I used came from this youtube video. I bought all the exact parts as he did.
YouTube - ‪DIY: How to build a laser diode driver‬‎
Im sure you guys have seen this before.

Also If there are any other household objects that have laser diodes worth extracting let me no as well.

Cheers

 

[Vaporizer]

I made my 1st driver circuit from that same schematic. It was posted elsewhere. I had seen that and abt 400,000 other vids on YT abt them. lol
I had a used LM317 in a drawer. It kinda works. I'm using 2 14500 900ma batteries in series. They read 7.365v loaded and the current draw can be adjusted from 35ma to abt 245ma. The laser diodes I removed from a CD & a DVD burner hardly illuminate. I measured the output voltage and its just barely over 3v at max current. This seems to low. I connected a LED to it and it will get slightly brighter at max, but never burn it up.
So, till I can get to RS, I'm down till I can get another one to try. It barely gets warm too. Not another good sign from all I've read here so far. A world of info on the forum.
I used a small brass tubed lens and it was bright enough to see and focus it at abt 1" to a pin point (no red beam), but thats all I could get from it. The body shell did get pretty warm so I'd just do 30-45 sec tries. Both are 3 lead, but I have no idea at this point if they have the capability to be a burner.
Off to read more threads!
Good luck on yours and be safe.

 

[Tux]

Ok I think Im going to scrap my PS3 laser build I think I damaged one of the diodes by trying to sauder with it or it making contact with powerfull magnet. The other diode works but the beam is weak and un focused, I can litarly stare into the diode, the LEDs ive hooked up to my power supply shine brighter:yabbmad:. So right no Im looking for any houshold objects that could be worth taking apart to extract the diode. I hear DVD or CD burners are good. Are they within the visable spectrum.

 

[chipdouglas]

ps3 lasers are like 40mw rated. also what color was the out put? also you might have "led'd" your diode. meaning it probably will never lase.

around here for simple projects we use a driver called the "ddl" it is named after the person who intoduced it here. but it is a driver based off of the lm317 regulator. it has resistors, a diode and a capacitor. also to start off cheap i recommend a "PHR" 405nm blu-ray. sorry for not posting links, i am lazy right now, i am currently nursing a hang over. there are so many diodes out there. you really have to becareful. don't use cd or dvd diodes. you want to use dvd burner diodes.

michael

 

[chipdouglas]

DON"T EVER STARE INTO A DIODE.... there are powerful infrared diodes that you cant see the light and will instantly fry your eyes!!!!! For somebody in APphysics you sure lack common sense LoL

and yes i double posted :na:

michael

 

[Vaporizer]

You can literally stare into the diode?!
From what I've read many CD type diodes are near IR and the eye has no blink response at that wavelength, along with you not being able to see the actual output.
I'm a noob to this forum, but not to electronics and some low power lasers.
You should never stare into one. Period.
My son and I use a digital camera or the web cam at an angle as it can see a wider range of light than the human eye. If it were accidentally get fried, due to a direct lase from bad placement, rather it than our eyes.

Please be careful. The eye damage a laser can cause is not reversible.

 

[Tux]

Ok I know that is a given (not to look into a laser diode) I have a summer internship in reaserch lab, we work in a lab that deals with helium neon lasers, so you can say Im sort of qualified to handel them. Im not retarded lol. I was actually building it in the lab during my free time.
I was extemly carefull up untill the point when I actually got it working, I was really disapointed it was so week.

What about a laser printer has anyone tried extracting diode(s) out of one.

@vaporizer Yeah I used a digital camera as well to get a better look at the spectrum, I wasnt to happy with the results of the picture at all so I looked around the laser diode in its last stage of the housing (no focusing lense) without looking directly into it.

 

[qumefox]

What color was the light? the BR diode will be a deep purple. They're also only good for I think less than 20mw. That pickup will have 650nm (DVD) and 780nm(CD) diodes as well.

Not sure why anyone would go to the trouble for less than 20mw. that little power at 405nm isn't going to be anything spectacular. You should get a PHR sled or diode. Look at the BST section. You can find then for <$10 and they'll do >100mw.

How many pins did each diode have? It was my understanding that the ps3's used a single diode with all three wavelengths but I could be wrong. If it had two diodes, the one with three pins is probably the BR, and the one with more is the combination DVD/CD laser

Laser diodes also won't have a beam by themselves. They need optics to collimate the beam.

As far as other things to scavenge diodes out of. DVD burners (not readers) will probably be the only thing that would catch your interest. CD stuff is 780, so it's IR for the most part. DVD is 650nm, so it's red. In general the faster the burner, the stronger the diode you can get from it.

 

[Kevlar]

DON"T EVER STARE INTO A DIODE.... there are powerful infrared diodes that you cant see the light and will instantly fry your eyes!!!!! For somebody in APphysics you sure lack common sense LoL

and yes i double posted :na:

michael

You should see his other thread: http://laserpointerforums.com/f38/casio-projector-445nm-1w-laser-pointer-build-53997.html#post760146

 

[qumefox]

That's... kinda scary. I think he needs to build a few low power builds successfully before jumping up to 1W... It's kinda like giving a 16 year old a Bugatti Veyron to learn to drive with.. Sure there's a chance nothing will happen but the most likely outcome is people getting hurt and a totaled car (or laser, in this case.)

 

[Tux]

Alright I'm listing to you guys, Ive been reading up on everything on heat sinking, Aixiz housing, drivers and battery types. I've scrapped my plans to build a 1w 445nm laser, and I am now looking at pointer with a 405nm PHR-803T out of a Xbox 360 HD drive.
It says in this graph: http://hacylon.case.edu/laser/diode_blu_roundup.PNG that I can reach 100mw, but is that wise to do, it looks like the power dropped a bit around 100ma.
I purchased the PHR-803 from High tech dealz along with the Aixiz housing, looks like an awesome site to get stuff cheap from america.

Ok this driver thing is still confusing the hell out me, I would preferably make my own from parts from radio shack, its not because I want to save money its just that I enjoy the feeling of creating something awesome. The driver that I had built for my PS3 LD did have a LM317 and a 25ohm resitor pot, instead of the 100ohm resistor pots im seeing in allot of the wiring diagrams in LPF. However I feel that I might have broken my LM317, when I pressed my finger on it the LM317 it burnt my finger, but looking at the schematics I realized its rated to work up 125C. Is there any way to test if it is broken or not. I want to get this one thing straight with you guys, the voltage regulator, being the LM317, all it does is make sure there is a constant voltage in the circuit, meaning it protects the LD from any influxes in voltage the battery may have?

Ok the main questions that has been bothering is:
How do I compensate for the voltage drop? Battery with higher voltage?
The recommended settings for the PHR-803T is a 100ma power being anywhere from 60-100mw, using P=IV the voltage should be 6-9V. So does that mean I use a 9V battery?

 

[qumefox]

Your radio shack still has actual electronic parts? Wow. The ones here have a few bins left, but they're pretty much all empty.

Back to the original question though. The ddl circuit your building is using the LM317 to regulate CURRENT. not VOLTAGE. There's a difference. Unless you know what your doing, you probably shouldn't change component values from what's specified. For the first build, stick to a design that's known to work. As far as if the LM317 is still good or not, that's fairly simple to test once you make sure the rest of the circuit and component values are correct.. Just put it on a test load (a 1 ohm resistor and a string of 6 1n4001's in series to emulate a BR diode) and measure the voltage across the 1 ohm resistor to read your driver's output current. mV = mA. If it's regulating current, then your LM317 is working fine. If not, replace it. Not like it'll break the bank to do so heh. If your worried about it getting hot, just put a heatsink on it.

As far as compensating for voltage drop. You have to remember the ddl circuit is a buck regulator. It's input voltage always has to stay higher than what the diode wants or else you lose power. For a PHR driven at 120mA, that will be around 5v. So if your battery voltage drops below 5v using this driver, the regulator's output power goes down as the battery dies. No way around this. I'd probably go with two protected 16340 lithium ion batteries in series. By the time they get down to their 2.75v cutoff (which would be 5.5v for both in series), your still above the 5v limit. Unprotected cells will work too but you really have to keep an eye on the voltage. Run them down past 2.75v and they're pretty much trash.

 

[Kevlar]

I saw that video too. It's probably the same thing but check out Rog's site, very easy to follow schematic for the "ddl" driver. Also, check out everything on his site, very cool and helpful stuff

Laser driver - It can be done

Here is another very helpful site by another LPF member:

Laser Man - Guides

 

[Cheech]

The driver in the youtube video in the OP is what I use for all my builds. The only thing I do different is I get rid of the pot/rheostat. I don't really care to dim my lasers, just full power. You should just build the circuit with a the 10ohm resistor to keep things simple for the PHR. Other than that I believe your ps3 builds probably just got fried because to much current,max I believe is 40ma. Don't worry about voltage drop, the diode will take what it needs with the 9v.
Have fun, good luck, keep reading.
http://laserpointerforums.com/f51/unfinished-build-guide-53972.html
http://laserpointerforums.com/f51/i-want-build-laser-thread-52972.html

^same as above

 

[Vaporizer]

I have 3 Radio Shacks within 20mi. 2 of them still have LM317's, 7805 regulators and the 1N4001's. One had the 25ohm pot. I have the circuit built and with one 10ohm resistor its current range seems to be 35-125ma. Adding the 2nd 10ohm in parallel for the 5ohm value increases its current range to just over 235ma.
Just as you said the voltage doesn't change with the pot. I'm using 1 & 2 14500 900ma lipos I have on hand.
I still need to build the test bed for setting up an initial test, then use a fixed resistor for the final build to save space.

Is there a chart somewhere I haven't found yet that lists the most popular laser diodes, the max voltage and current they can live with? Or is it a look up on each one for a pdf?
One thread I found on here shows needing the voltage required for the diode added to the voltage needed for the LM317 plus 1.2v for proper operation. It came out at 7.2v for a red and 9v for a BR stating the BR needed 4.5v.

Thanks for all the info.

Edit: Ok, that info was from rog's page and the answer is below the diode examples:
"You could put 12v or more in for either laser diode all that will happen is that the regulator turns any volts it cannot use into heat."

So, it showing the minimum voltage needed to operate. This will help keep it close with ample input current and the heat down. 12v on a red 3v is gonna have a bunch of heat to get rid of to the heatsink & host where 5v would be much less if I read that correctly.

 

[chipdouglas]

I have 3 Radio Shacks within 20mi. 2 of them still have LM317's, 7805 regulators and the 1N4001's. One had the 25ohm pot. I have the circuit built and with one 10ohm resistor its current range seems to be 35-125ma. Adding the 2nd 10ohm in parallel for the 5ohm value increases its current range to just over 235ma.
Just as you said the voltage doesn't change with the pot. I'm using 1 & 2 14500 900ma lipos I have on hand.
I still need to build the test bed for setting up an initial test, then use a fixed resistor for the final build to save space.

Is there a chart somewhere I haven't found yet that lists the most popular laser diodes, the max voltage and current they can live with? Or is it a look up on each one for a pdf?
One thread I found on here shows needing the voltage required for the diode added to the voltage needed for the LM317 plus 1.2v for proper operation. It came out at 7.2v for a red and 9v for a BR stating the BR needed 4.5v.

Thanks for all the info.

the laser diodes are are close to each other in voltage +/- 1.5vdc. so you will basically want to set everything up around your host.

what batts does the host take?
what is the possible voltages you can make
-3v, 3.7, 9, 12?
from there you can decide on the driver
linear
boost?
if your host can only take a configuration of max 5.5 then you will want a boost.
but if your host can take up to 12 then you might want a linear.
once this is figured out the think about how much current your diode can handle.

micahel