Adafruit Small Liquid Crystal Light Valve - Controllable Shutter Glass

A Liquid Crystal Light Valve (LCLV) offers an innovative approach to light control, leveraging liquid crystal properties layered between glass sheets. Often found in applications like electric welding helmets, LCLVs shield eyes from harmful light exposure but also present creative possibilities for various projects with a controllable "reveal" effect by adjusting opacity levels.

The technology functions akin to individual pixels in LCD displays, utilizing a small, tinted gray LCD segment to filter visual input. By applying voltage across two electrodes, users can modulate the light passage—from starting at 1.0VDC for initial darkening to reaching near opacity at 4.0VDC, with 5V as the maximum recommended voltage.

While incapable of blocking 100% light, the LCLV achieves up to 95% opacity and requires minimal current. Notably, it retains its darkened state post-activation until a 0V signal is applied or a draining resistor is connected. When utilized continuously as opaque, an AC square wave prevents potential damage from DC bias. Handle with care: the glass is delicate and must remain intact without bending or cutting.