[Dino’s] hack this week seeks to create sunglasses that dim based on the intensity of ambient light. The thought is that this should give you the best light level even with changing brightness like when the sun goes behind a cloud or walking from inside to outside. He started with a pair of 3D shutter glasses. These have lenses that are each a liquid crystal pane. The glasses monitor an IR signal coming from a 3D TV, then alternately black out the lenses so that each eye is seeing a different frame of video to create the stereoscopic effect. In the video after the break he tears down the hardware and builds it back up with his own ambient light sensor circuit.
It only takes 6V to immediately darken one of the LCD panes. The interesting thing is that it takes a few seconds for them to become clear again. It turns out you need to bleed off the voltage in the pane using a resistor in order to have a fast response in both directions. Above you can see the light dependent resistor in the bridge of the frame that is used to trigger the panes. [Dino] shows at the end of his video that they work. But the main protective feature of sunglasses is that they filter out UV rays and he’s not sure if these have any ability to do that or not.
Continue reading “Turning 3D shutter glasses into automatic sunglasses”
This circuit is how [John Tsiombikas] makes his cheap 3D shutter glasses work with a Linux machine. It’s not that they were incompatible with Linux. The issue is that only certain video cards have the stereo port necessary to drive the head-mounted hardware.
Shutter glasses block light from one eye at a time, so that different renderings can be shown to create the stereoscopic effect. Since stimulating the muscles in the eye doesn’t actually work, you need to find a way to drive the glasses in perfect time with the video signal. His circuit watches for the V-Sync signal, then uses it to toggle the shutter glasses. Since the hardware has no way of knowing whether the left or right frame is being generated, he included the toggle switch as a user-controlled adjustment. If the 3D isn’t coming together, you’re probably viewing the frames with the wrong eye and need to flip the switch.
There’s really no way to show the effect without trying out the hardware in person. But [John] reports that it works like a charm when used with the OpenGL stereo wrapper.
[Jonathan Post] has a way to watch 3D video without wearing shutter glasses but it might be kind of a hard product to break into the market. As you can see above, a pair of electrodes are stuck on a viewer’s eyelids, using electricity to alternately close each eye. The video after the break shows a demonstration of this technology. Obviously a camera can’t capture the image that the viewer sees, but this man describes a perfect 3D image. This reminds us of those ab exercisers that use electrodes to stimulate the muscles. Do you think a 3 hour epic would leave your eyelids tired and sore, eventually resulting and a steroid-esque muscle-ridden face?
Edit from [Caleb]: Judging from the comments, some people believe this to be an absolute impossibility. While we concur that this example is pretty silly (what’s powering those electrodes?), we invite you to watch [Daito Manabe]’s facial electrodes fun.
Continue reading “Electrodes turn your eyelids into 3D shutter glasses”