Large Liquid Crystal Light Valve Controllable Shutter Glass

A Liquid Crystal Light Valve (a.k.a a LCD Controllable Black-out Panel)! They're often used for electric welding helmets because they can protect the welder's eyes from the bright sparks. Or – if you aren't a welder – they can be used to provide a "reveal" effect for your project, as you can control the opaqueness of the LCD. A Liquid Crystal Light Valve (LCLV) is a device that uses the properties of liquid crystals to control the level of illumination passing through an optical system. It's basically what goes on in your LCD monitor/TV/projector etc, but for each individual pixels.

In this product, we have one huge LCD piece, which will filter what you see through it. Normally, its a tinted gray color (because the light around us is not polarized, it is not completely clear). There are two sets of electrodes, on the left and right. The two pins closest to each other (on the edges) are the same electrode, and the LCD is symmetric so you can use either one as positive/negative.