<html> <p>Laser microphones have been around since the Cold War. Back in those days, they were a favorite tool of the KGB – allowing spies to listen in on what was being said in a room from a safe distance. <a href=„https://www.youtube.com/watch?v=EiVi8AjG4OY“ rel=„noopener“ target=„_blank“>This project by [SomethingAbtScience]</a> resurrects that concept with a DIY build that any hacker worth their soldering iron can whip up on a modest budget. And let’s face it, <a href=„https://hackaday.com/2011/02/22/darpas-hummingbird-spybot/“>few things are cooler</a> than turning a distant window into a microphone.</p><p>At its core this hack shines a laser on a window, detects the reflected light, and picks up subtle vibrations caused by conversations inside the room. [SomethingAbtScience] uses an ordinary red laser (visible, because YouTube rules) and repurposes an amplifier circuit ripped from an old mic, swapping the capsule for a photodiode. The build is elegant in its simplicity, but what really makes it shine is the attention to detail: adding a polarizing filter to cut ambient noise and 3D printing a stabilized sensor mount. The output is still a bit noisy, but with some fine tuning – and perhaps a second sensor for differential analysis – there’s potential for crystal-clear audio reconstruction. Just don’t expect it to pass MI6 quality control.</p><p>While you probably won’t be spying on diplomats anytime soon, this project is a fascinating glimpse into a bygone era of <a href=„https://hackaday.com/2018/05/18/tiny-transmitter-brings-out-the-spy-inside-you/“>physical surveillance</a>. It’s also a reminder of how much can be accomplished with a laser pointer, some ingenuity, and the curiosity to see how far a signal can travel.</p><p><iframe title=„I Built a CIA Spy Device (Laser Mic)“ width=„800“ height=„450“ src=„https://www.youtube.com/embed/EiVi8AjG4OY?feature=oembed“ frameborder=„0“ referrerpolicy=„strict-origin-when-cross-origin“ allowfullscreen=„allowfullscreen“>[embedded content]</iframe></p> </html>