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An electronic writing instrument introduced in 2010 by the Improv Electronics division of Kent Displays. Using the accompanying stylus and resembling a handheld memo pad, the battery-operated devices use a type of LCD writing surface that retains its image without power. Boogie Boards are erased by pressing a button.

In 2011, the Boogie Board Rip added internal storage for saving approximately 200 images as PDF files, which were transferred to a computer via a USB cable. Two years later, the Sync model added more storage along with transmission via Bluetooth to Evernote, email and social media. See cholesteric LCD.

Boogie Board eWriters
Available with writing surfaces from 4.5" to 10.5", Boogie Boards are used to jot down just about anything. (Images courtesy of Kent Displays Inc.,

cholesteric LCD

A bistable LCD screen that retains its image without power. Cholesteric LCDs use nematic liquid crystal molecules in a layered, spiral formation (chiral nematic), and power is only required to change the image. An advantage of most cholesteric screens over the common nematic LCD is that they can be viewed in bright sunlight. They can also be made on flexible plastic rather than glass. See liquid crystal and LCD.

Write, Retain and Erase
Boogie Boards use cholesteric LCDs to retain the user's notes written with an accompanying stylus. Pressing a button erases the board by switching the screen from its reflective planar state to its transmissive focal-conic state. (Image courtesy of Kent Displays Inc.,

A Cholesteric Readout
This authentication token circuit board uses a cholesteric readout to display the current password. (Image courtesy of Linear Dimensions Semiconductor,

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