Laser Diode Power Output Based on DVD-R/RW specs

I’ve opened about a dozen different types of CD and DVD drives so far (of both read-only and burner varieties) and every time it’s a thrill to find a working red laser diode in there. But it would be useful indeed to know what performance can be expected from the laser diode once it’s free of its mounting hardware (AKA “sled”) – if it’s the laser diode you’re after, the drive may not even be worth opening. It would be nice to know that before wasting some time on opening it. Although it would be hard to know the exact specs of the diode down to the part number, some of the specs can be found rather quickly doing an Internet search. Here is how I do that.

First off, run an Internet search for the part number. Usually, you don’t even have to leave the first page of the search results in your favorite search engine. There’s normally someone still selling these drives (unless it’s a VERY old model) and they put all the info you need to know right in the title of their listing: Philips dvd8631 16xdvd±rw dl ide drive . So, it’s a 16-speed, dual layer writing DVD drive, so it does have a high power red laser in it.
The power of the laser can be assessed based on the advertised speed.

According to Sony’s product brochure for one of their high-power red laser diodes, SLD1236VL, the diode’s output power (CW or continuous power) will be somewhere along this list:

• x4 speed recoding – 100mW
• x8 speed recording – 140mW
• x12 speed recording – 200mW
• x16 speed recording – 250mW
• x16 Dual Layer speed recording – 300mW
• x24 Dual Layer speed recording – 400mW

You can also venture a really rough guess based on the date of manufacture if by some very strange reason no info about your drive is available on the Internet (what is it, from Mars?) or you’re just been really lazy:

• 2002-2003 – x4 speed recoding – 100mW
• 2003-2004 – x8 speed recording – 140mW
• 2004-2005 – x12 – speed recording – 200mW
• 2004-2005 – x16 – speed recording – 250mW
• 2005-2008 – x16 speed recording Dual Layer – 300mW
• 2008-current x24 speed recording Dual Layer – 400mW

Note that many of the most recent drives have laser diodes either without any package (bare silicon inside the optical assembly) or on really hard to work with glass plates. You may want to stay away from those.

Ideally, what you are looking for (from the DIY perspective) is a red laser diode of 200mW+ optical power output in a TO-18 package, meaning a round metal body with the larger diameter of 5.6mm – the size/shape most prevalent among suppliers of mountings for the diode, such as AixiZ or O-Like. This diode operates at 2.5V and 130mA current and has a wavelength of 658nm.

So, your ideal drive to harvest parts from, at least for DIY CNC laser cutting purposes, is usually manufactured in 2005-2008 and it’s a desktop drive advertised as a 16x speed recorder. So, yeah, this Phillips drive was a good pick …

Happy harvesting!

Oh, and before you go: even the lowest power laser diodes mentioned here will burn your retina if you’re not careful, so use proper laser safety glasses!

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