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. They are 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.

Specifications:

• Outline size: 96.5 x 38.0 x 2.0 mm
• View area: 88.5 x 34.5 mm
• Driving voltage: 5.0V
• LCD type: TN, transmissive, positive
• Operating temperature: -10ŒÁ to 60ŒÁ
• Product Dimensions: 97.0mm x 38.0mm x 2.0mm / 3.8" x 1.5" x 0.1"
• Product Weight: 14.4g / 0.5oz