Hci 1st presentation
Download as PPTX, PDF
1 like180 views
This document discusses different types of display screens including bitmap displays, CRT displays, LCD displays, random scan displays, direct view storage tubes, situated displays, and digital paper. Bitmap displays store images as grids of pixels which can be translated into dots for printing or pixels for screens. CRT displays use electron guns to project images onto phosphorescent screens but are bulky. LCD displays are thinner, lighter, and can display more colors than CRTs. Random scan displays draw images line by line. Direct view storage tubes behave like CRTs but write images to a wire grid instead of a screen. Situated displays include large screens for meetings and small public displays. Digital paper uses dot patterns to store handwritten notes digitally
Hci 1st presentation
- 3. Display Screens Bitmap,CRT, LCD,Random Scan, Direct View Storage Tube, Situated Displays, Digital Paper
- 5. A representation, consisting of rows and columns of dots, of a graphics image in computer memory. The value of each dot (whether it is filled in or not) is stored in one or more bits of data. For simple monochrome images, one bit is sufficient to represent each dot, but for colors and shades of gray, each dot requires more than one bit of data. Most modern personal computers & working stations have bitmap displays, allowing the efficient use of Graphical User Interfaces & interactive graphics. Bitmap screens
- 6. To display a bit-mapped image on a monitor or to print it on a printer, the computer translates the bit map into pixels (for display screens) or ink dots (for printers). Optical scanners and fax machines work by transforming text or pictures on paper into bit maps. JPEG, TIFF, and PNG graphics files are examples of bitmap images. Bitmap Images
- 7. In computers, resolution is the number of pixels (individual points of color) contained on a display monitor, expressed in terms of the number of pixels on the horizontal axis and the number on the vertical axis. The sharpness of the image on a display depends on the resolution and the size of the monitor. Resolution
- 8. Aliasing:- Aliasing is an effect that causes different signals to become indistinguishable when sampled. Anti-aliasing:- Antialiasing is the smoothing of the image or sound roughness caused by aliasing. Aliasing & Anti-Aliasing
- 9. The cathode ray tube (CRT) is a vacuum tube containing one or more electron guns, and a phosphorescent screen used to view images. Within the CRT are three electron guns, red, green, and blue. Each of these guns streams a steady flow of electrons, left to right, for each line of your monitor. Bulky, heavy, use vacuum tube technology. Using technology that was developed in the 19th century Cathode Ray Tube electron gun focussing and deflection electron beam phosphor- coated screen
- 10. Do not sit too close to the screen Do not use very small fonts Do not look at the screen for long periods without a break Do not place the screen directly in front of a bright window Work in well-lit surroundings Take extra care if pregnant. but also posture, ergonomics, stress Health Care Hints
- 11. Most are capable of displaying unlimited colors. Multiple video Resolutions Faster response time Look a very wide angle Advantages of CRT
- 12. Liquid-crystal-display televisions (LCD TV) are television sets that use LCD display technology to produce images. LCD televisions are thinner and lighter than cathode ray tube (CRTs) of similar display size, and are available in much larger sizes LCD a type of display used in digital watches and many portable computers. Liquid Crystal Display
- 13. Top plate transparent and polarised, Bottom plate reflecting. Light passes through top plate and crystal, and reflects back to eye. Voltage applied to crystal changes polarisation and hence colour Less eye strain How LCD Works
- 14. Compact & Lightweight Space saving Can be mounted on wall or panel Consume less energy & more durable Does not emit radiation Lower Prices in the Long-Term Advantages of LCD
- 15. Random-scan monitors draw a picture one line at a time and for this reason are also referred to as vector displays. lines need to be constantly redrawn On zooming in ,it remains Smooth rarely used except in special instruments Cannot display realistic shaded scenes. Random scan displays are designed to draw all the component lines of a Picture 30 to 60 times each second. No jaggies Random Scan
- 16. Conceptually the Direct View Storage Tube (DVST) behaves like a CRT with highly persistent phosphor. Pictures drawn on there will be seen for several minutes before fading. It is similar to CRT as far as the electronic gun and phosphor-coated mechanisms are concerned. But instead of the electron beam directly writing the pictures on the phosphor coated CRT screen, the writing is done with the help of a fine-mesh wire grid. Direct View Storage Tube
- 17. Can be incrementally updated but not selectively erased Used in analogue storage oscilloscopes No flicker Direct View Storage Tube
- 18. Used for meetings, lectures, conferences, etc. Usually wide screen Lots of small screens together Large Displays
- 19. displays in public places Framed photographs, blackboards in classrooms, posters, billboards, road-signs are all visual forms of communication that play a vital role in the way we understand, navigate and behave in our environment. They inform us about places, and events of interest and reflect the activities of others. Although location matters Situated Displays
- 21. Digital Paper Digital paper, also known as interactive paper, is patterned paper used in conjunction with a digital pen to create handwritten digital documents. The printed dot pattern uniquely identifies the position coordinates on the paper. The digital pen uses this pattern to store the handwriting and upload it to a computer
- 22. The dot pattern is a kind of two dimensional barcode. The complete pattern space is divided into various domains. These domains can be used to define paper types, or to indicate the paper's purpose (for example, memo formatting, personal planners, notebook paper, et cetera). Digital Paper