Strangest drive/sled I've ever opened up.

I've opened up quite a few drives, and taken a peak at quite a few sleds. However tonight, after a sudden urge to open an old T0$h1ba SD-M1212 DVD ROM that I gutted (along with various wiring, a PSU, a fan, and an enormous heatsink) from a dilapidated computer that we were getting rid of, I found at least half a dozen oddball things, borderline new discovery. The first odd thing, was TWO diodes. This was new to me, I was used to ROMs carrying simply an IR diode, I then checked the face-plate, sure enough, ROM. I checked further, a warning specified a visible laser, and an invisible laser. So one of these is a red diode, and that's good news (even if it's 5mW, you'll understand why a little later on.) Further peaking lead to the most bizarre setup I've seen for a diode. No orange wiring to PCB or anything, one diode was soldered directly to the PCB. Another oddity? Neither diode has/had the optics assembly/array commonly linked to IR diodes within ROMS and writables. On top of that, I found a distinctively "weird" can design, a very odd circular lens assembly, and this sled is one of the most lacking in the lens department, that I have ever seen (a total of 5, including the cubes, outside lenses, everything.) I've taken over a dozen pics of this sled and it's contents, I will be posting them tomorrow with a description of each, and a bit of a more thorough "write-up" when I have a little more motivation (very sleepy.) So for now, consider this a "teaser" I'll update tomorrow with everything else. Sleep tight fellas, more to come!

Fascinating. Can't wait to see some pictures!

Its odd, but the researchers did come up with a whole new design on this one.
One step forward to the making of Superdrives in that decade, i would really like to see the insides..

Annnnndd we're off! So, upon first looking at the driver, you will see the warning label, this particular warning specifies a VISIBLE laser, and an INVISIBLE laser

Then, upon opening the beat (also the largest drive I've seen/held) You will see it's enormous circuit board, literally as large (in length and width) as the drive itself:

Then after getting through all the goodies (no pictures of that, sorry folks, if there's a large enough desire then I'll try to pick up another of these drives in about a month when I have spare change to do so) You will find the sled. And what a strange sled it is.
The "front"
The "back"
Notice the circular lens housing? The tons of orange wiring/pcb? The TWO diodes almost right next to each other? (look at the top of the "back" picture)
Closer looks at the first diode don't reveal much, just a generic diode in a heatsink:


However, taking a peak at the OTHER diode, reveals some additional oddities:

Is that directly on the PCB???

As a matter of fact, it is!

Before fiddling too much with the diode, let's look at the sled some more shall we? I removed the lens assembly after unscrewing 3 VERY solid screws. Notice the single lens, and it's circular shape, rather than the usual rectangle held with 2 magnets and a lens in the center with wires. A very "unique" design.


Now, a look into the sled's optics, notice how lacking it is? For a sled with two diodes, this sled is remarkably lacking in the optics department.



Only FIVE optics (the fifth one is pictures on the circular lens assembly.) However, I think I've made you wait long enough for the good stuff Remember that bizarre diode I was talking about? Well, here it is.

Notice anything strange yet? How about after these?


Now you see why it's so weird? Literally an entirely new can/diode design. At least for me anyway. What could this be used for? Why slant it? Why TWO diodes? Why the circular design? Why solder the diode directly to the PCB? Why such an enormous circuit board to control it all? So many questions, so many mysteries. This really was quite an exciting drive to open! Thanks for staying the whole show, please pick up any trash you created, and single file out the doors please

All jokes aside, if anyone has any ideas about this very bizarre sled and design, please post here! I'd love to know what's up here

Maybe one laser was the reading laser and the other was there for optical correction? Just my thought, on laser pre-reading the disk while looking for anomolies in the surface and using that info to make corrections in the second laser's focus.

Are the pictures resized for yall? I noticed 4 weren't, so I resized them and cleared my cookies so I'd notice the change, now those 4 are the only ones that are for me....

Very cool, in particluar i like the slanted window on the diode. Perhaps its set up at a brewster(spelling?) angle although you would think something like that wouldn't be needed on a diode.

Amazing pics buddy!! Really worth the whole show.. and +1 for the new can design discovery.. People at To$h!ba are crazy.. lol.. now hook'em up and see what these diodes actually do.. Mainly the one curved out n all..

My scientific mind wants if know if you hooked up the crooked 1 and if so what was it. I have found a 4 pin similar to yours

Bloom, did you ever hook it to a driver and see wha it did?

grgguy said:

My scientific mind wants if know if you hooked up the crooked 1 and if so what was it. I have found a 4 pin similar to yours

Click to expand...

I guarantee you it'll be either a low powered red, or a semi high powered (still low end of Class IIIB) IR, as far as output and dot shape, no clue.

tsteele93 said:

Bloom, did you ever hook it to a driver and see wha it did?

Click to expand...

I am incredibly tempted to, but all I have at the moment are linear drivers at 119mA+, and I have no clue how much it needs :thinking: I am dying to though.

Perhaps the red was used to read the DVDs, and the IR used to read any CDs placed in the drive. That can design is quite something indeed. Never seen one like it. Perhaps, as mentioned, the window is placed at the brewster angle. If you fire these up, post some pics ...

I got a 4 pin of the same design . I do not know what to do with it(i am completely noob)
http://laserpointerforums.com/attachment.php?attachmentid=37421&stc=1&d=1333496967
http://laserpointerforums.com/attachment.php?attachmentid=37422&stc=1&d=1333496967

For CD/DVD/Blue-Ray drives, the physical layout of the media (and particularly how tight the tracks can be packed together) is a function of the wavelength of the laser the media was designed for (shorter wavelength lasers allow you to pack the data more tightly, and thus store more data on the same size disc).

For CD's this will always be IR, for DVD's this will always be Red, and for Blu-Ray this will always be violet. For drives that support more than one format, a laser appropriate for each format is required.

In this particular case, the drive in question is an old (1999) 6X DVR-ROM / 24x CD-ROM. It thus needs 2 LD's - an IR one to read CD's, and a Red one to read DVD's.

(BTW, this drive was reported to be "finicky" / have problems with reading some disks. Perhaps this "angled" case design did not work as well as they had hoped, which may be why we don't see this today?)

So being ROM's we can assume very low power? We need burners for decent diodes, correct? Thanks!