How do Bistable LCDs work: Introduction

Bistable LCDs, also called e-paper displays are a newer display technology that allows the LCD glass to hold an image without the need of any power. One common example of this technology can be found in the amazon Kindle.

At this time, the majority of bistable LCDs are monochrome and are limited to one color background and a different color font. There is newer technology available that allows the module to display multiple colors, but has not been widely accepted into many products.

This article is the first in a multi-part series written to answer many of the questions we receive when designing a bistable LCD. The majority of e-ink displays are custom LCDs and are manufactured according to the customer’s specifications. By the way, bistable is pronounced as [bahy-stey-buh l] which is bi + stable meaning having two stable states.

Bistable LCDs: How do they work?

Suppose you had a pile of quarters on a table top. You paint one side of each quarter black and the other side white. Now, you want to layout the quarters as a black letter ‘L’. So you flip all the quarters over to their black side and arrange them so they look like a large L.

The black ‘L’ will not change as long as the quarters are not moved. In other words, no energy is required to keep ‘L’ visible.

Now you want to change the black ‘L’ to a white ‘L’. You simply flip all the quarters over to their white side. This would require a small amount of energy, but once you are done flipping the quarters, your white ‘L’ would continue to display without the need of any new energy.

This is an oversimplified example of the bi-stable liquid crystal display technology. To read the next article in this series, click part two.

If you are READY to design your custom Bistable LCDs, contact a member of our technical support staff at 480-503-4295.