As an LED display manufacturer, NanoLumens is predictably most focused on emissive display technologies, or those that create and emit light of their own. LED displays are an example of such a display technology, hence the “E” in the acronym, which stands for Emitting. (Here’s an article about how the light emission process works.) Emissive display technology is of course not the only display technology out there however, so I’d like to take the opportunity to briefly touch on an alternative display technology, how it works, and what makes it different. The technology I’ll be covering here is that of reflective displays, and in sharing my thoughts I simply hope to assist display owners in understanding the range of options they face so they can make informed purchase choices.
What Are Reflective Displays?
Reflective displays are a digital display solution that reflects the ambient light of its surroundings rather than creating and emitting light of its own. This non-emissive technology is frequently referred to as electronic paper due to the way its appearance mimics that of traditional ink on traditional paper, which makes its content substantially more legible in environments with high levels of ambient light. Consider the bright environment efficacy of the most recognizable application for this technology, e-reader tablets like the Kindle, in contrast to that of an LED, LCD, or otherwise backlit display. Amidst bright sunlight, like at the beach for example, the backlit products will shine far brighter but their content will likely be more difficult to view. This is because while emissive displays must outshine the ambient light around them, reflective displays draw their brightness from the ambient light.Reflective displays are a digital display solution that reflects the ambient light of its surroundings rather than creating and emitting light of its own. Read more here: Click To Tweet
How Do Reflective Displays Work?
Unlike an emissive display, which creates its own light through electroluminescence, reflective displays simply redirect and repurpose the light that already exists around them. This style of reflective display technology was originally pioneered in the 1970s by researchers at Xerox, who found that by embedding microscopic polyethylene two-colored spheres (Janus particles) within bubbles of oil arrayed across a transparent silicon sheet, they could manipulate the rotation of the spheres to show one color or another. On one side of these spheres was negatively charged black plastic, while the other side featured white plastic with a positive charge. The researchers discovered that by adjusting the polarity of the potential applied to the electrode layers encasing the layer of sphere-filled bubbles, they could alter which side of the spheres faced up. This binary system allowed for the display of rudimentary images, and more importantly, of text. This packaging process is very different from the LED packaging process, detailed here.