See the Difference: New Age Display Technologies

The central idea behind every communication is to create an

impact. The central idea behind computing is to provide information in a better

and more useful format, one that is also comprehensible to the user. Whether it

is in the field of advertising, with those huge billboards of every size, shape

and nature, or in the field of mass communication, visual is the king.

Today, there is huge competition for that last square inch

of eyeball. So where and how is your eyeball oriented and how best can the

information presenter present it more comfortably and efficiently to you?

Naturally, every use of a display has its own special needs.

From stylish wrap-around displays that you can roll up and

carry under your arm to gigantic ones that scroll commodity trading prices and

information at Times Square, displays have evolved greatly from original cathode

ray tube based monsters that generated more noise and heat than understanding.

The Cybersphere is a VR environment used for virtual tours and gaming. It uses a spherical enclosure around the participant to produce life like images are realistic locations

World of 3D



The world is not flat, it is 3D. The world of 3D display has so far been a

misuse of the human binocular vision to create an illusion of depth. But are

real 3D displays on the horizon? So far, such displays had a tendency to use

lasers and holographic projection in the air. Prime examples of such visual

acrobatics are the laser light shows that have become passé at various opening

ceremonies. Such visual effects may seem to be frivolous at the outset, but have

some real world practical uses.  For instance, you could virtually tour a

geographically far off or otherwise inaccessible location in 3D, sitting in a

comfortable sofa and sipping your favorite drink. Before approving the next

architecturally marvelous office, you could actually walk through it at the

architect's office. Students could explore distant caves or under-sea

locations sitting in virtual labs on dry land without fear of storms. True

holographic displays are still far off from the realism of the Star Trek 'Holodeck'.

Today, they are at best projections from multiple projectors over a curved piece

of glass that requires a lot of work on the image quality before anyone would

accept it as real.

The National Institute of Advanced Industrial Science and

Technology in



Japan



, in partnership with Burton Inc has started development on precisely such 3D

technology using high-intensity lasers that are focused onto points, generating

plasma emissions from the material. However, so far, they have only been

successful in projecting simple and linear images. And, such images are highly

'pixilated' with even straight lines appearing as a collection of dots in

the air. They can use multiple lasers to create more pixels.

When you have images projected directly onto your retina, it's like watching a 14” screen from 2' away. It's used in the USA for military and medical purposes

Directly into the eye



VRD (Virtual Retina Display) is an advanced display system. Unlike other means
to display, a 3D image technology bypasses the need to first form the image on

some medium and then has the eye see it. Instead, the images are directly

projected onto the retina.

This technology is being developed and prototyped for the



US



military and medical usage, where users need not be tied down to large and

bulky equipment that are not very portable and unsuited for use on the

battlefield or at a surgical station. Head-mounted systems are used in VRD for

projection. Since the images are projected this way, the realism of the image is

higher than those with holographic projection. However, this does not mean that

it is uncomfortable to look at the image, since adjustments are made to simulate

the feel of watching the image on a 14-inch monitor from a distance of 2 feet.

Current enhancements to the technology include simulating the details that human

eye sees, when actually looking at the image 2 feet away.

Roll it up



Face it: nothing is as comfortable to read as that magazine or newspaper on

paper that you can carry around anywhere you please and read at any angle that

suits your pleasure. Plus, traditional means of display (like LCDs and CRTs) are

not very friendly to be anything other than flat in shape. However, just like

the planet we are on, not everything around us is flat in nature. This means

that people who want to attract more eyeballs need to use non-flat displays on

non-flat surfaces. Like the huge curved display of the NYSE on

Times Square

. This particular display is a huge 120 by 90 foot monster (that's about eight

stories).

Researchers at the NIAIST Japan can create simple lines and shapes in 3D using multiple lasers focussed on different points to emit plasma	The futuristic holodeck of the USS Enterprise in Star Trek Generations could project real images like this vessel in the sea and let its users interact with the environment

However, this particular screen still uses LEDs, a

technology not very friendly to being worn as a T-shirt or wrapped around your

wrist.For that, we need to use something called 'electronic ink' (or e-ink).

E-ink is a mixture of the realms of physics, chemistry and electronics. What

happens is that there are millions of tiny nanocapsules that contain charged

particles suspended in a clear fluid medium. White color is rendered by positive

particles while black is a result of negative charges. As different currents

flow through the medium, the particles flow around and change the appearance of

the screen and create text or image. Because of the nature of these capsules and

its operation, such displays are feather-light and highly flexible. But it is

currently only black and white. This is currently the display technology that

powers the Sony LIBRe, with major players like Philips and Plastic Logic

conducting research on extending its use to other devices that are rollable,

wearable, light and flexible at the same time.

Giant ink color billboards



While we're talking about ink, lets look at another form of display ink:

Magnetic Ink (MagInk). This ink is used in giant billboards that receive

information wirelessly   and display news, advertisements or sports

scores. These large outdoor billboards are also built to be rugged and

weather-proof, maintaining clear visibility even in bright sunlight, ideal for

use in public places.

Organic LED and polymer based displays make highly flexible and multi-purpose displays like this one possible

MagInk uses a paste that changes wavelengths in response to

electronic signals. This results in a color display. The paste is applied to a

thin sheet of glass or flexiplastic, similar to how PCBs are manufactured. This

is sandwiched with a substrate to form the display. Electrical fields through

the upper and lower layers change the charges in MagInk resulting in the

display. Just like with CRTs and LCDs, the visual is a set of pixels in a

matrix, each of which are driven by separate signals. However, unlike those

displays, when the electronic signal is stopped, the visual remains on the

screen till a new signal is sent. This results in lower power consumption since

you no longer require driving a continuous charge through the matrix to keep the

picture alive. This is 10% cheaper to produce than the conventional LED screens

of the same size.

Light responsive displays



How would you like it if the photographs on your wall showed different

shadows and aspects according to how light fell on it? This is exactly what

Light Sensitive Displays do. The display senses the direction and intensity of

the light source present in the room and changes the image accordingly. This

effect lets the image become a part of its environment. This is currently under

research at the



Columbia



University



.

Shine a light from any direction on a Light Sensitive Display and it will sense the light and its direction to change shadows in the picture it is showing

This can be adapted to reflect the current mood of the room

and ambient environment, highly useful to enhance relaxation and reduce stress

whether it be in office or at home.

Organic & polymer displays



No, they aren't eatable yet. Organic LED (OLED) has taken over from

traditional LED. It has a faster response time and can be adapted easily to a

large number of uses. It is possible to print (yes, OLEDs are printed, not fixed

unlike the LED) them onto a variety of materials, like even cloth. Plastic or

Polymer LED (PLED) is another hot LED-based technology. But its cost of

production is around the same as of an LCD screen of the same dimensions. These

technologies are the ones that can realistically take forward the dream of

electronic newspapers that one can carry around, with the value addition that it

can display even video instead of just still photography.

The biggest challenge with OLED and PLED is its limited

life spans, mainly because organic matter decomposes quickly. But even then,

such displays can easily last you a couple of decades, which is quite a long

time.

Displays have clearly evolved from the initial noisy boxes

that could only show a sine wave. But they haven't yet reached a stage of

constancy. Several individual technologies, like CRT and LCD have matured, but

there are other interesting and futuristic technologies that are coming up to

take their places. Like everything else, electronic display is also an area of

rapid development.

Sujay V Sarma