[andre] sent in his first attempt at using a HD-DVD laser diode to expose photosensitive resist to create PC boards. We’ve been meaning to give this a shot with the ol’ Epilog laser cutter. For the test, he coated the board with some resist and hand exposed it with the laser. Finally, he etched it with some sodium hydroxide.
Laser Hacks652 Articles
RGB Laser Diode Projector
[fl-consult] published this interesting RGB laser diode projector. The build uses three lasers, 532nm green, 660nm red and a 405nm blue diode from an XBox 360 HD-DVD drive. Aside from the salvaged diodes, it uses some off the shelf hardware to power and scan the lasers to make the display. Details are a bit lacking, but google translate helps a bit. If you’re not quite sure what’s going on: the three lasers bounce off of a set of mirrors that scan from side to side as well as up and down to create images.
M3 Headphone Amp
If you’re serious about your headphone amps, you probably already know about the M3 headphone amplifier. Instead of going for the extra tiny, they’re going the ‘screw the size, it’s all about the sound’ route. Thsi thing needs a 24v .5amp power supply. Boards are available, and the discussion has gotten so long on headwize that they exceeded the maximum thread length.
I got busy with the laser last night and came up with something new: a custom etched track pad. It still works, with a bit of added texture where I introduced it to the warm glow of the laser. Hit the link for pics and a walk through.
Ablative Power On My Doorstep
After months of waiting, emailing and waiting some more, I took the afternoon off to stay home and wait for this special delivery. (I had to wait an extra day due to a shipping issue!) I received three huge boxes in my workshop. Not only did I receive this (not so mini) Epilog mini 24, I put together a stand and unpacked a monster air filter.
Read on for the obligatory Hack-A-Day logo and my first impressions of this sweet piece of kit.
Laser-writing Via Vnc
Writing with a laser pointer has been done, but [Chris]’s roll your own version feeds the data the display pc using VNC. He’s got some speed issues, but I’m giving him points for most original use for remote desktop software.
24C3 Toying With Barcodes
[FX] from Phenoelit gave an entertaining talk about barcode security. He covered both how the systems are implemented and how they’ve been exploited. The first example was a parking garage in Dresden that issues non unique barcodes for the unlimited passes that hotels give out. Anyone code print out an image of that particular code and park for free. German grocery stores have automated machines that refund you for your empty beer bottles. The barcode generated just states the refund amount (5 digits) that you’ll get at the register. Just stick the barcode under something like a six pack and it’ll scan even without the cashier seeing it.
Check out the video to find out more silliness involving DVD rentals, boarding passes, asset management, and SQL injection via the scanner. You can even find higher res versions in the 24C3 media archives.
Convert A DVD-R Drive Into A Lab Scanner
[bodiby] was first to send in this New Scientist article about converting a DVD drive into a lab scanner. I did some digging and came up with the details. Here’s the paper describing the process and results. Here’s a basic schematic and description of the mod. A set of samples is placed onto a CDR. A photo sensor is used to locate the samples on the CD, while the laser is fired through each sample. A planar photodiode is used to measure the attenuation of the laser as it’s transmitted through each sample. Sadly, I couldn’t find any details on the custom control electronics.
