Stories tagged diffraction

Sep
05
2010

Quest for the best optical display

Better resolution displays
Better resolution displaysCourtesy Yutaka Tsutano

I have been waiting for the new iPod Touch. I want a display screen so sharp, it looks like a photograph. The "retina display" creates an image out of pixels that are only 78 nanometers. How small is that? Well, more than 300 of these pixels are packed in each inch. Supposedly this is the limit for human perception, or as some fanboys might say, "It doesn't get any better than this!"

Plasmonic nanoresonators

University of Michigan researchers can do better, though, Their paper in Nature Communications titled, Plasmonic nanoresonators for high-resolution colour filtering and spectral imaging explains how pixels of only 10 microns can be produced.

Such pixel densities could make the technology useful in projection displays, as well as wearable, bendable or extremely compact displays, according to the researchers.

How does it work?

The resonators are kind of like a light filter. Two nano thin layers of metal selectively allow light to pass through small sets of slits. The slit spacing determines which wavelength of light makes it through the slits.

Red light emanates from slits set around 360 nanometers apart; green from those about 270 nanometers apart, and blue from those approximately 225 nanometers apart. The differently spaced gratings essentially catch different wavelengths of light and resonantly transmit through the stacks. LinuxForDevices.com

These displays are simpler, use fewer parts, are more efficient, and should be cheaper to make. I am not going to wait, though.

Jewel  bug colors
Jewel bug colorsCourtesy arquera
Georgia Tech scientists provided a detailed explanation of how the jeweled beetle Chrysina gloriosa creates the striking colors using a unique helical structure that reflects light of two specific colors.

A cholesteric liquid crystalline material, which self-assembles into a complex arrangement of polygonal shapes each less than 10 microns in size, causes interference within reflected light resulting in bright green light with a wavelength of 530 nanometers mixed with yellow light in a wavelength of 580 nanometers.

Learn more by reading this Georgia Tech news release.