Graffiti Research Lab's [James Powderly] along with 9 other Tibet supporters were deported from China during the Olympic's closing ceremonies. Detained on the 19th, the activists were to serve a 10 day sentence, but the Chinese government buckled under international pressure and deported them early. This brings the total number of deported activists to 53 since the start of the games.
The new Epilog Zing is designed to bring laser engraving to the home for personal use. It's got 25 watts of power, a small enough footprint to fit neatly on your desk, and the video above shows it has a pretty high resolution. But compared to the mini18, the Zing has less Z movement, a lower wattage, a smaller engraving area, and about half the speed. Also, with a price set around $8,000, we don't think many people will be buying them for personal use just yet. However, if you have a small home business that requires these services, the Zing could be perfect. If you are looking for more information on laser engraving, see [ladyada's] laser information page.
[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.
[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.
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.
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.
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.
[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.
[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.
[John] sent in this cell phone activated rifle scope laser security camera blinder. The phone plays a tone when it receives a SMS message. The sound activates an audio controlled relay. (Not elegant, but it works) which powers a laser that's been mounted to a rifle scope. The scope is used to align the laser with the target lens - on activation it's supposed to blind the camera. Looks like a fun hack, even if the uses are a bit nefarious. (He left out a little detail that'll make or break the project to keep things on the level, but it's not that hard to figure out.)
[Mike] wanted a better power supply for his argon laser, so he modded some switchmode power supplies. With a few tweaks, he had a few adjustable voltage outputs and a nice solid supply of electrons for his laser projects. If you need a lab quality adjustable power supply for your projects, this is a nice way to get it on the cheap. (He's in the UK, but the same ideas should apply to us models.
I found this on [hackedgadgets] and checked out the paper describing the project. I'm not sure if it will generate any truly usable graphics any time soon, but the technology is pretty interesting. It combines six video channels and uses acoustic frequencies and tiny but simple looking transducers to vibrate the crystal that channels a laser to generate the hologram. (If I read that paper correctly) Surprisingly, a single nvidia chip generates all six channels for the system. Annoyingly, there's a lack of info on MITs site, but there's a nice group of images under the multimedia link of this article.
This hack was linked a bit back in February, but it just didn't get a decent write up. They used this 5000 lumen projector, a zoom lens video camera and a 60mw green laser pointer to generate interactive graffiti on nearby buildings. Most of the link love focused on the show-off video. I'm surprised that nobody mentioned the most obvious use: a laser pointer reactive white board. I could have loads of fun with this and my laptop during presentations. Thanks to [Brishen] for reminding me of this one.
I signed the papers on my first house today! In celebration, I started looking for some home hardware hacks, but stumbled across this old (2003) laser power meter sensor. If you like to scare off the power guys, this is the way to go. [jake] used a laser pointer, probably a PIC and some sort of photo sensor to count the revolutions of his meter.
