Laser Hacks

654 Articles

24C3 Toying With Barcodes

December 30, 2007 by 24 Comments

[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

September 25, 2007 by 17 Comments


[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.

Remote Laser Security Camera Defeat

August 11, 2007 by 35 Comments


[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.)

Switchmode Power Supply Hacking (power Your Laser)

July 27, 2007 by 7 Comments


[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.

Acoustically Generated Holograms

July 8, 2007 by 5 Comments


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.

Interactive Laser Drawing (graffiti)

May 26, 2007 by 14 Comments


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.