[over9k] used his Arduino to set up a laser trip wire. The laser is mounted along side the Arduino, reflects off of a mirror, and shines on a photoresistor that interfaces via a voltage divider. The ...

As a preview of his latest book, Arduino Project Handbook: 25 Practical Projects to Get You Started, Mark Geddes takes us through the project to create a simple laser trip wire alarm. You've probably ...

Sometimes security doesn’t need to be overly complex to be effective. Instructables user [1234itouch] recently built a simple laser tripwire alarm that can be mounted virtually anywhere, complete with ...