virtual retinal display- kaustuv chakraborti(cse 27)

8/14/2019 Virtual Retinal Display- Kaustuv Chakraborti(Cse 27)

1/14

Virtual Retinal Display

Kaustuv Chakraborti

Roll no-06/CSE/27


2/14

What is it?

A virtual retinaldisplay (VRD), alsoknown as a retinal scandisplay (RSD) or retinal

projector, is a displaytechnology that draws araster display (like atelevision) directly ontothe retina of the eye. The

user sees what appearsto be a conventionaldisplay floating in spacein front of them
http://en.wikipedia.org/wiki/Rasterhttp://en.wikipedia.org/wiki/Televisionhttp://en.wikipedia.org/wiki/Retinahttp://en.wikipedia.org/wiki/Retinahttp://en.wikipedia.org/wiki/Televisionhttp://en.wikipedia.org/wiki/Raster


3/14

History

In the past similar systems have been made by projecting adefocused image directly in front of the user's eye on asmall "screen", normally in the form of large glasses. Theuser focused their eyes on the background, where thescreen appeared to be floating. The disadvantage of thesesystems was the limited area covered by the "screen", thehigh weight of the small televisions used to project thedisplay, and the fact that the image would appear focusedonly if the user was focusing at a particular "depth". Limitedbrightness made them useful only in indoor settings as well.


4/14

How it started?

The VRD was invented at the University of Washington in theHuman Interface Technology Lab in 1991. Most of this research intoVRDs to date has been in combination with various virtual realitysystems. The development began in November 1993.

The aim was to produce a full color,wide field-of-view, highresolution, high brightness, low cost virtual display.

Microvision Inc. has the exclusive license to commercialize the VRDtechnology.

This technology has many potential applications, from head-mounted displays (HMDs) for military/aerospace applications tomedical society.
http://en.wikipedia.org/wiki/University_of_Washingtonhttp://en.wikipedia.org/wiki/Human_Interface_Technology_Labhttp://en.wikipedia.org/wiki/Virtual_realityhttp://en.wikipedia.org/wiki/Virtual_realityhttp://en.wikipedia.org/wiki/Human_Interface_Technology_Labhttp://en.wikipedia.org/wiki/University_of_Washington


5/14

Why Do we need it?

Our window into the digital universe has long been a glowingscreen perched on a desk.It's called a computer monitor

Advantages like full color,wide field-of-view, high resolution, highbrightness, low cost virtual display.

The VRD system scanning light into only one of our eyes allows

images to be laid over our view of real objects.

VRD system can also show an image in each eye with a very littleangle difference for simulating three-dimensional scenes with highfidelity spectral colours..

This system only generates essentially needed photons, and as

such it is more efficient for mobile devices that are only designedto serve a single user. A VRD could potentially use tens orhundreds of times less power for Mobile Telephone and Netbookbased applications.


6/14

How it works?

The Virtual Retinal Display presents video information by scanning modulatedlight in a raster pattern directly onto the viewer's retina.

As the light scans the eye, its intensity is modulated. On a basic level, as shown

in the above figure, the VRD consists of a light source, a modulator, vertical andhorizontal scanners, and imaging optics (to focus the light beam and opticallycondition the scan).


7/14

The resultant imaged formed on the retina is

perceived as a wide field of view imageoriginating from some viewing distance in space.

The following figure illustrates the light raster on

the retina and the resultant image perceived inspace.


8/14

Safety first

It is believed that VRD based Laser or LED displays are notharmful to the human eye, as they are of a far lowerintensity than those that are deemed hazardous to vision,

the beam is spread over a greater surface area, and doesnot rest on a single point for an extended period of time


9/14

UTILITY


10/14


11/14

Medical Utilities

A similar system can be usedby doctors for complexoperations. While a surgeonis operating, he can keeptrack of vital patient data,

such as blood pressure orheart rate, on a VRD. Forprocedures such as theplacement of a catheterstent, overlaid imagesprepared from previously

obtainedmagnetic resonance imagingor scans assist in surgical

navigation.
http://en.wikipedia.org/wiki/Magnetic_resonance_imaginghttp://en.wikipedia.org/wiki/Magnetic_resonance_imaging


12/14

Gaming industry

Applied to video games, for instance, gamers could have anenhanced sense of reality that liquid-crystal-display glassescould never provide, because the VRD can refocus

dynamically to simulate near and distant objects with a farsuperior level of realism.


13/14

Moving forward

The fact that LEDs are able to provide needed light forVRD, makes cheaper and easier VRD manufacturing. Thetotal amount of light that enters the eye from a desktopdisplay is actually less than a microwatt, which is small

compared with what an LED can contribute.

On the other hand, although the power required is low,light must be collected and focused down in a point. Thisis easy to do with a laser, but not so easy with an LED.

Even so, advances in LED technology have been neededto further concentrate the light coming from thesedevices.
http://en.wikipedia.org/wiki/LEDhttp://en.wikipedia.org/wiki/LED


14/14

virtual retinal display- kaustuv chakraborti(cse 27)

Documents