Red / IR Combo Diode From Poineer BDR-205 12x Sled

I just recently bought a couple of 12x sleds, pioneer bdr-205/bk. I was reading a thread where someone mentioned that the red 3.8mm LD in these sleds have a nicer beam.

So I carefully pulled mine out, and the whole time examining the sled, noticed I could not find the IR LD??

I checked the paperwork in the box as I was sure that it said it 'writes to CD'..

Here is where the caution comes in. Not sure if this was covered, but nothing turned up in the search.

It seems that the OEM for these diodes have made a two in one 780nm / 650nm combo LOC diode! Both are obviously burners..

Now if you were to accidentally hook up the LD upside down, you may expose your eyes to some nasty IR.

We all know that 780nm looks like 1mW of red, when it is much higher and much more dangerous.

Moral of the story, double check your connections as getting this backwards could result in some damage to your peepers.

On the other hand, we can now make combo red and ir pens etc, both burners with one lens

The 3rd pin on the bottom which would be the PD feedback or an unused pin is now the + for the IR and the case being ground for both red and IR.

I looked at the diode before wiring it, and saw 2 connections going to the chip. I was actually hopeful that this may be a sign of a higher output, but when tested was the 780nm. Interesting none the less, and possibly useful to some.

Play safe..







I was able to run both chips at the same time as seen in the pic below. The red on its own is still producing that line through the beam. Even at threshold current (70-80mA) the line is present. I was really hoping it wouldnt be there but ah well.

When both beams are lit at the same time, the first thing I noticed was that the dots only overlap one another at a few mm away from the laser. At 3ft away, the dots are already a few inches apart. They dont line up which I found kind of odd.

Here are a few more pics, the one with the goggles is with both wavelengths running and only the IR passing.

Thanks for the PM about this. I was just looking for red in mine but I have tested it now for IR and I'm getting 215 mW @ .320 mA -- That's using a Jayrob 650-G-1 lens assembly.

The original BluRays we got had all three lasers in one package. They can't put out a single beam because the chips are stacked and have different focal points. That isn't a problem because it isn't wise to run both at the same time due to heat conduction if they are stacked. If one blows, it may damage the lens on the other.

HMike

Hemlock_Mike said:

Thanks for the PM about this. I was just looking for red in mine but I have tested it now for IR and I'm getting 215 mW @ .320 mA -- That's using a Jayrob 650-G-1 lens assembly.

The original BluRays we got had all three lasers in one package. They can't put out a single beam because the chips are stacked and have different focal points. That isn't a problem because it isn't wise to run both at the same time due to heat conduction if they are stacked. If one blows, it may damage the lens on the other.

HMike

Click to expand...

Thanks for the input..


Does yours also have the flat line in the reds beam? I usually see this in other high power reds, but this one appears as low as threshold.

I did in the process however, figure out how to make a nice thin beam... Much closer to the type seen on a 532nm.

I had some modules from 2 or more years back that were ment for a flat chip. A 5.6mm diode will not fit in them, but this new red does. The lens looks just like an aixiz acrylic, but less than a 3rd the size. The resulting beam if far more sharp, with a dot at 20ft which looks like that of one of my He/Ne's..

So there does seem to be some promise with these little guys after all

The red does produce the line as I bring it up but after threshold, I can't see it.
Because of the different junction voltages of the diodes, you can't run them in parallel and as I said earlier, don't run both at high power and for short times.

Kind of a neat little bonus in these diodes!

HMike

Im surprised nobody noticed the normally neutral pin had a wire going to the chip, and not a PD which is usually absent anyhow.

I see what you are saying about the line disappearing though. It is not as pronounced as in the bigger diodes, but still visible at 360mA for me.

It just doesnt stick out like a sore thumb. I will see if it completely goes away at 400+mA

Joe --

I think the 650-G-1 lens gets in so close to the diode that it doesnt get much of the stray beam. At 400 mA, you should read 280 to 300 mW depending on lens.

HMike

I did notice the wire going to the chip and to both insulated pins and had to test and found the differnt junction voltages the chip operates at, that is when I knew it had to be two different chips. I been to busy to mess with it but I will try to have some microscope pics up shortly.

wannaburn said:

Im surprised nobody noticed the normally neutral pin had a wire going to the chip, and not a PD which is usually absent anyhow.

I see what you are saying about the line disappearing though. It is not as pronounced as in the bigger diodes, but still visible at 360mA for me.

It just doesnt stick out like a sore thumb. I will see if it completely goes away at 400+mA

Click to expand...

Discussion on this IR part of the SmOC diode is now on two threads.
http://laserpointerforums.com/f50/mini-red-diodes-47774.html

HMike

I am in the habbit of looking LD's over before I even solder them. I look for any debris, especially when the diode is so clammed up in a case and an OC.

It was a tricky extraction, but the metal is not nearly as brittle as say a phr, which allows you to kinda peel it back and away from the LD. The way this thing is encased, a brittle mount would likely lead to damage of an open can.

Some pics would be nice, I can only get so close up..

A neat thing about these that I noticed is the red emmits only from the left side. Its really noticable when just above threshold current.

Flaminpyro said:

I did notice the wire going to the chip and to both insulated pins and had to test and found the differnt junction voltages the chip operates at, that is when I knew it had to be two different chips. I been to busy to mess with it but I will try to have some microscope pics up shortly.

Click to expand...

Interesting stuff...

Thanks for sharing!

Hemlock_Mike said:

Joe --

I think the 650-G-1 lens gets in so close to the diode that it doesnt get much of the stray beam. At 400 mA, you should read 280 to 300 mW depending on lens.

HMike

Click to expand...

Just to mention about my 650-G-1 Mike, it's AR coating is specifically for 600nm to 1050nm... (which you probably knew)

Jay -- That lens assembly focuses real nice for my testing at ~ 2' -- OWCH
I haven't tried it farther out because it's hard to see!

HMike

Your talking about IR right Mike?

Jay -- The lens seems to work good for the IR too!

HMike

Maybe a dumb question, but... Will the full diode break if you break one part of it?

If one burns out, it's the luck of the draw. The other one may work but it depends on the failure mode and how much smoke was made. As more of these become available, maybe someone will test this (by accident!!).

HMike

Isnt there a thread about this same diode in the veterans section?

any good info from there that can be transfered here?