Finally we see a hack that is focuses on safety when it comes to high-power laser hacks. A safety switch has been added to the butt of the flashlight body which houses the laser diode. When the safety is flipped on an LED blinks to prompt the user for a security code. If you enter the correct code on a momentary push switch, electrical access to the laser is enabled. There are also a couple of nice features such as continuous on and auto shutoff.
This would be hard to implement if you’re working on a watertight package but we like the fact that an unsuspecting house guest won’t go blind if searching for a flashlight during a storm. One last thing, the code entry system is PIC based which reminds us of [Alan Parekh’s] one-button system.