An easy cheap pointer to blue laser conversion??

[bbshamsa]

Hi all, just wondering if it's easy to save a lot of hassel of building a driver and casing etc... when all you seem to need do is find a pointer with a pot, remove the diode, measure the current with a multimeter and adjust till you reach 60-90mA and finally pop a harvested blue diode in... To put it simply

I read that xbox 360 hd dvd drives have blue lasers that run well around that current.

Apologies if this is really underestimating the issue, but it just seems possible considering the only difference from one laser's driver and power source and another seems to be the diode it serves and its optimal operating current.

 

[phoenix3200]

Re: An easy cheap pointer to blue laser conversion

Unfortunately, it's not that easy.

Blu-Rays take 4.5 volts minimum, and many of these drivers can't produce more than 3 volts.  If it's running off two AA batteries, the driver manufacturer had no reason to introduce a boost converter on their driver.

In addition, the drivers are (usually) not constant current drivers.  They're either constant power, or the laser diode has an integrated photodiode for monitoring the diode.

 

[artix]

Re: An easy cheap pointer to blue laser conversion

Also it isn't blue or even blu-ray. The most popular PHR 803T is from an HD-DVD drive. We just like calling it blu-ray because it sounds cool and it is easy to remember.

 

[Spyderz20x6]

Re: An easy cheap pointer to blue laser conversion

Also it isn't blue or even blu-ray. The most popular PHR 803T is from an HD-DVD drive. We just like calling it blu-ray because it sounds cool and it is easy to remember.

Correction:

They use PHR-803T Sleds in 2x [highlight]SONY[/highlight] Blu-Ray burners.

What now?

 

[artix]

Re: An easy cheap pointer to blue laser conversion

[quote author=Artix link=1229045458/0#2 date=1229050203]Also it isn't blue or even blu-ray. The most popular PHR 803T is from an HD-DVD drive. We just like calling it blu-ray because it sounds cool and it is easy to remember.

Correction:

They use PHR-803T Sleds in 2x [highlight]SONY[/highlight] Blu-Ray burners.

What now?
[/quote]

Remember this?

Not only is this drive an HD DVD-ROM drive is can also read DVDs and CDs with quick speed and accuracy.

 

[Spyderz20x6]

Re: An easy cheap pointer to blue laser conversion

[quote author=Spyderz20x6 link=1229045458/0#3 date=1229050464][quote author=Artix link=1229045458/0#2 date=1229050203]Also it isn't blue or even blu-ray. The most popular PHR 803T is from an HD-DVD drive. We just like calling it blu-ray because it sounds cool and it is easy to remember.

Correction:

They use PHR-803T Sleds in 2x [highlight]SONY[/highlight] Blu-Ray burners.

What now?
[/quote]

Remember this?

Not only is this drive an HD DVD-ROM drive is can also read DVDs and CDs with quick speed and accuracy.

[/quote]
Well, i've got news for you:
A Toshiba is not the only place it is used...

 

[phoenix3200]

Re: An easy cheap pointer to blue laser conversion

They use PHR-803T Sleds in 2x [highlight]SONY[/highlight] Blu-Ray burners.

I learn something new every day...

 

[Xplorer877]

Re: An easy cheap pointer to blue laser conversion

when all you seem to need do is find a pointer with a pot, remove the diode, measure the current with a multimeter and adjust till you reach 60-90mA and finally pop a harvested blue diode in... To put it simply

You cannot measure current without a load. DDMs have no resistance in current mode. You will ruin the meter and the driver.

-Pablo Gilberto

 

[xmtgx]

Re: An easy cheap pointer to blue laser conversion

[quote author=bbshamsa link=1229045458/0#0 date=1229045458]when all you seem to need do is find a pointer with a pot, remove the diode, measure the current with a multimeter and adjust till you reach 60-90mA and finally pop a harvested blue diode in... To put it simply

You cannot measure current without a load. DDMs have no resistance in current mode. You will ruin the meter and the driver.

-Pablo Gilberto[/quote]
I'm curious on to how would you ruin your multi-meter by doing this? I know it's incorrect and not trying to argue with you or anything, just curious.

 

[Xplorer877]

Re: An easy cheap pointer to blue laser conversion

When ever you measure current in a circuit you have to measure it through the load. In this case it would be the diode. In the simplest of circumstances the amount of current drawn from the power supply is dependent on the resistance of the load, assuming voltage is constant.

So if you leave out the diode and connect the leads to the diode driver you will essentially be shorting the driver. Since there is no resistance across the driver it will create a flood of power to flow, regardless of the current limiting abilities of the driver, and damage the driver. Now since all that power is flowing through your DMM if it cannot handle it, it can be damaged due to trying to measure too much current.

My mini DMM only measures up to 250mA. Some larger models support in excess of 20A so these wont be damaged because there is no way that a small diode driver will supply >20A even if it's shorted. However, if you have your driver set to measure mA, which is likely because diode current is small enough to be expressed in mA, then it can be damaged. Most new DMM have over current protection or fuses, so come to think of it, it may be unlikely that you will break it.

Power supplies and drivers supply voltage. It is up to the resistance and voltage through that resistance that determines the current flow.

Lol, I know this may be overkill but I was bored. ;D

-Pablo Gilberto