Lock & unlock your computer screen with Lemonscreen

By Mark O’Neill
Contributing Writer, [GAS]

Maybe I have seen too much of Star Trek and other sci-fi series on television but there is something about being able to lock and unlock something with your face or your voice.   It kind of makes your text password pale in comparison when all you have to do is sit down in front of your monitor and your face is all that’s needed to unlock your screen.

That’s precisely what Lemonscreen does.   It’s a small program for Windows XP only that scans your face with your webcam, saves the scan in its memory and then uses that face scan to lock and unlock your PC.   When you go to set it up, you have to sit in front of your webcam, press the button and let it scan you, making sure that your face is inside the little red square.

Then when you want it to scan your face to get back into your computer, make sure your face is inside that red square again.

It looks like a fairly basic program but I would say it does the job very well.    I sat down in front of the computer, the scan clicked on and the computer instantly unlocked.    I put a soft toy in front of the computer and it didn’t unlock.   I put my girlfriend in front of the computer and it didn’t unlock.   I put a friend who is a close resemblance to me in front of the computer and it started to move as if it was considering whether this guy was me or not.   But to its credit, it decided my friend wasn’t me and refused to move.

The only downside to it is that the Lemonscreen screen that appears on your computer when it locks has a constant webcam monitor running, so if you happen to be walking past and your face gets caught in that red square then you could unintentionally unlock your computer!

But all in all, this is a great program.  I wouldn’t rely too heavily on it from a security point of view – after all, anyone can drag your face in front of the webcam to unlock your computer.    But if you’re just stepping away from the screen for a few minutes to make a coffee or grab a sandwich, and you fancy something different on your screen, then why not try out this?    I guarantee you’ll be the talk of the office.


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