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Ans:1- When operated as a random-scan display unit, a CRT has the electron beam directed only

to the parts of the screen where a picture is to be drawn. Random-scan monitors draw a picture

one line at a time and for this reason are also referred to as vector displays (or stroke-writing orcalligraphic displays). The component lines of a picture can be drawn and refreshed by a

random-scan system in any specified order (fig). A pen plotter operates in a similar way and is an

example of a random-scan, hard-copy device.

Refresh rate on a random-scan system depends on the number of lines to be displayed. Picturedefinition is now stored as a set of line-drawing commands in an area of memory referred to as

the refresh display file. Sometimes the refresh display file is called the display list, display

program, or simply the refresh buffer. To display a specified picture, the system cycles throughthe set of commands in the display file, drawing each component line in turn. After all line-

drawing commands have been processed, the system cycles back to the first line command in the

list. Random-scan displays are designed to draw all the component lines of a picture 30 to 60times each second. High-quality vector systems are capable of handling approximately 100,000

"short" lines at this refresh rate. When a small set of lines is to be displayed, each refresh cycle is

delayed to avoid refresh rates greater than 60 frames per second. Otherwise, faster refreshing ofthe set of lines could burn out the phosphor.

Random-scan systems are designed for line-drawing applications and can-not display realistic

shaded scenes. Since picture definition is stored as a Set of line-drawing instructions and not as a

set of intensity values for all screen points, vector displays generally have higher resolution thanraster systems. Also, vector displays produce smooth line drawings because the CRT beam

directly follows the line path. A raster system, in contrast, produces jagged lines that are plotted

as discrete point sets.

Raster-scan Display Processor :- One way to set up the orangyation of a raster system containinga separate display processor,sometimes referred to as a graphics controller or a display

coprocessor.the purpose of the displays processor is to free the CPU from the graphics chores. In

addition to the system memory, a separate display-processor memory area can also be provided.A major task of the display processor is digitizing a picture definition given in an application

program into a set of pixel-intensity values for storage in the frame buffer. This digitization

process is called scan conversion.Display processors are also designed to perform a number of additional operations. These

functions include generating various line styles, displaying color areas, and performing certain

transformations and manipulations on displayed objects. Also, display processors are typically

designed to interface with interactive input devices, such as a mouse.

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Ans(5)-Sony is the most technologically advanced but is a bit more pricey and could cost you a

few hundred more than the Samsun with the same features. Quality of picture and other small

factors make the Sony a better choice especially for those who want more class and features. Butwhen you don't want to pay those extra hundred dollars, the Onida is a great preference. The

value for money for a Onida is much more than anything you could get from any other brand.

Simply said the price is Justifiable.

One data point: We actually have a Onida LCD TV and it's amazing. We chose it over Sony

because we heard that the Sony's have more TV's that need to be repaired.

Another data point: In the last few years, thousands of Onida customers have suffered from a

devastating problem that Onida has been very slow to respond to. Just google "Onida lcd tv click

capacitor" to see the many people who were impacted by Onida's decision to use inadequatecapacitors in their power supplies. There are several videos on youtube on how to repair this

problem; one has over 50,000 views.

Refers to a variety of technologies that provide a real-life 3D visual appearance that is displayedin print, in a computer, in the movies or on TV. The 3D in this context, also called "stereoscopic

imaging" and "3D imaging," differs from 3D graphics, 3D computer-aided design (CAD) and

regular 3D animations. Such images may be rendered very realistically as 3D objects, butviewers clearly do not sense real depth. See 3D graphics and solid modeling.

With 3D visualization, people, animals and nature seem truly alive as if the viewer could walk

right into the environment. Even 3D cartoon characters seem more real. However, 3Dvisualization is not just for entertainment; the more realistic a 3D training session, the greater thetest of a person's reactions.

Virtual Reality

Virtual reality is a type of 3D visualization that is used in space flight simulators as well as

games and entertainment. Wearing 3D goggles, the illusion of reality comes from interactingwith physical wheels, dials and pedals, as well as being immersed in a 360-degree environment.

Such systems may employ traditional 3D rendering or may use 3D visualization methods as

described here. See virtual reality and 3D goggles.

Creating 3D - Stereoscopic Images

The creation of 3D is accomplished by capturing the scene at two different angles correspondingto the distance between a person's left and right eyes (roughly 65 mm). When the stereoscopic

(dual) images are directed back to left and right eyes, the brain perceives the illusion of depth.

The stereo images are either displayed together but separated by colors (anaglyph method) or by

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polarization, or they are alternately displayed very rapidly. A pair of 3D glasses corresponding to

the 3D technology filters the image to the appropriate eye. See stereoscope and3D glasses.

3D Stills

3D still pictures date back to the 16th century when "binocular" images were viewed cross eyed.In the 1800s, stereoscopic viewers (stereoscopes) were developed. Today, 3D stills are created

with a 3D camera or a 3D lens on a regular camera. A rudimentary method is to join two cameras

together and snap them at once. There are other formats, but the anaglyph RGB color methodusing glasses or viewers is popular.

3D Cinema

In the 1950s, the first 3D movie theaters used the anaglyph color method, and the audience wore

paper glasses with red and blue/green lenses. This method has been superseded by 3D equipment

on the movie projector that polarizes the left image onto the screen differently than the right

image. The audience wears polarized 3D glasses that direct each eye to the correct image.Similar methods are used for conferences and training. The key concept is that the polarized 3D

eyewear is matched to the 3D polarization used by the projector.

3D Kiosks

Various "auto stereo" methods divide images into multiple blocks and display them as if coming

from several angles to provide an illusion of depth without the viewer having to wear 3D glasses.

Used in shopping malls and retail stores for advertising and promotions, such equipment iscostly, and the 3D illusion varies.

3D on the Computer and TV

In the 2009-2011 time frame, 3D made initial inroads onto computers and TVs, especially for

gamers, requiring a 3D display adapter for the computer or a 3D TV set. Using LCD shutter

glasses, the left and right stereo images are alternately displayed very rapidly. An infraredemitter mounted near the screen transmits to the user's glasses, which open and close the left and

right eyes in synchronization with the stereo frames.

In 2009, NVIDIA introduced 3D Vision, a system that converts 2D content on the computer into

3D in real time, and Texas Instruments added 3D capability to its DLP rear-projection TVtechnology. Even the old anaglyph color method is sometimes used with DVD movies, and the

DVD package may include a pair of anaglyph glasses

Ans-6

(a)OCRsoftware converts the scanned images of documents, into word searchable documents

which can be computer stored, edited or printed as required. The management of documents is

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one of it's most valuable uses these days, which replaces the need for paper based filing systems.

A real benefit of Optical Character Recognition software is the time saved on data entry of

information from returned paper forms and the re-typing of text, such as from old books or

documents, when there is no computer based original is available.

The OCR software detects and extracts each character in the text of a scanned image, and using

the ASCII code set, which is the American Standard Code for Information Interchange, converts

it into a computer recognizable character.

Where as OMRsoftware analyzes multiple-choice hand marked responses from bubble sheet

questionnaire forms. It extracts the determined marks and converts them into captured data

information which can be used for automatic marking and reporting in education and market

research . The software determines the presence or absence of a mark in the checkboxes, by

measuring the amount of darkness in each box and can process thousands of forms per day. The

speed and accuracy of the software depends on the scanner used and the images it produces.

Lower resolution, sharp scanned images will take up less space on the computer and process the

results much faster than a high resolution poor quality image.

(b) In a LCD display each pixel acts as a switch, they dont emit any light. Instead there is awhite back lighting. This light passes through the liquid crystal then through colour filter. The

liquid crystal solution is trapped between two polarised glasses. Each sub-pixel is controlled

electrically and thus more or less light is allowed to pass through the crystal, then through thepolarised glass on to the display surface. Controlled red, green, and blue shades are thus emitted.

Where as in In a plasma display, electricity is used to excite the gas atoms inside the miniature

cells forming the display panel, which in turn release ultra-violet photons. The radiated UV

causes the phosphor lining on these minute cells to emit energy in the form of visible coloredlight - the color of which depends on the type of phosphor used to line the cell.

Each of these cells is further sub-divided into three sub-cellsas will be explained further on, each representing one of the

primary light colors (click on image for more details).

Sandwiched between the glass-plates are long electrodes on

both sides of the cells. The address electrodes sit behind thecells along with the rear glass plate while transparent display

electrodes sit in front of the cells covered by a protective layer

along the front glass plate.

'Three' sub-cell

structure of a plasmadisplay pixel

image courtesy of

howstuffworks.com

http://void%280%29/

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When a voltage is applied between the plasma display electrode and the respective address

electrode, an electric current flows through the gas in the cell - simulating the gas atoms to

release ultraviolet photons. This ultraviolet radiation excites the phosphor lining on the insidewall of the cell - giving off energy in the form visible light.

The phosphors in a plasma display are arranged to give off colored light - red, green or blue - tobuild a color image. As already indicated earlier on, each picture element in a display panel is

made up of three sub-pixels - each acting as a miniature light source for one for each of theseprimary light colors.

These colors blend together to create the final color of the pixel; this is very much the same with

the way colors blend in CRTs and LCDs.

The pixel brightness in a plasma display is then controlled by using pulse-width modulationtechniques. This means that by varying the duration of the voltage pulses applied to the sub-pixel

electrodes several thousand times per second, it is possible to control the intensity of the resultant

current pulses flowing through the individual cells. This in turn energizes each sub-cell phosphorat different levels to generate increased or decreased intensity of colored light - in line with the

picture content. This makes it possible for plasma displays to generate billions of different

shades of color - leading to extremely accurate color reproduction and smooth film-like image.

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