Computer graphics

 • CRT have 2 kind of display technique 1) Vector scan Display 2) Raster scan Display • We will here First discuss about Vector scan Display. A ) Vector Scan Display. 1) Vector Scan Display is a technique used for producing images on the screen. 2) There different names for Vector Scan Display as follows: a) Vector Scan Display b) Random scan Display c) Calligraphic Display d) Stroke - Writing Display 3) In this technique electron beam is only directed to the area on the screen where picture is to be drawn. 4) Above image is one of the popular diagram to depict the working of Vector Scan Display. 5) Here you can see, electron beam is working like a pencil on the screen and only beams in a particular area only not on the whole screen point to be noted. 6) The  picture is constructed out of a sequence of straight-line segments. Each line segment is drawn on the screen by directing the beam to move from one point on the screen to the next, where its x & y coordinates define each point

Important: During discharge the positive is a cathode, the negative is an anode. During charge the positive is a anode, the negative is a cathode.   What is CRT? => CRT is a device which converts electrical signal into visual signal. • Now before anything else it's important to understand the working and it's diagram properly. • let's see work of each component in this diagram 1) Cathode: Cathode emits electron when it gets heat up by heater. => Cathode can be(Cobalt,Nickel,and manganese) => Anode made of(Zinc and lithium) 2) Grid Focuses and pass Electron beam at high speed. 3) Pre Accelerating Anode: It provides path to electrons 4) Vertical deflection plate: It deflects electrons beam up or down direction on screen as y-axis does 5) Horizontal deflection plate: It deflects electrons beam Right or left as X-axis does. 6) Aquadag coating: If electrons comes out of their path then it repels and helps electrons to come again in focusing path 7) Screen is coated with

 • We all use in are day to day life different types of Computer for instance different color, size, shape, and brand, we also have different types of monitor too. • So let's have a look on different types of monitor available in market • Different types of monitor 1) CRT (Cathode Ray tube) 2) LCD (Liquid Crystal Displays) 3) TFT (Thin Film Transistor) 4) LED (light Emitting Diodes) • There are two type of CRT display available: 1) Raster Scan Display 2) Vector Scan Display • We will discuss both the display one by one, but before that we will study how CRT works? in further post. * You can leave a comment if you have doubt in it.

  1) 3000 * 4000= 1,20,00000 pixels Or 12 megapixel 2) one million pixels= 1 megapixel. 3) You might have heard many times the word megapixel mostly when you mention about your camera details, what does it means? 4) The amount of details that the camera can capture is called the resolution (w*h), and it is measured in pixels. 5) More the Pixel camera has, more detail it can capture and the larger pictures can be without blurry or "grainy". 6) Aspect ratio is ratio of width to height of device. • Example: 16 inch(horizontal) and 9 inch(vertical) 16:9= 1.77. Here 1.77 is the Aspect ratio. * If you want to increase the size of resolution the pixel size has to be decreased and vice versa. * Resolution is technically the number of Pixel per unit of area. • Let's have a look to chart of different resolution available. 1) SD(480) Standard Definition       = 640*480 => 640:480 = 1.3(Aspect ratio). 2) SD(480) = 720*480 =>720:480=>1.5(AR) 3) HD 720 High definition or 720p=

 • First we will understand the meaning of Resolution. 1) Resolution measures the number of Pixels in a digital image or display. 2) It is defined as width by height                            OR • W * H  ->where W is number of horizontal rows or pixels ->And H is number of vertical columns or pixels. • As we studied in earlier topic of what is Pixel that pixels are arranged in grid of horizontal and vertical form. 3) Let's take the example of Resolution  • Image Resolution= 1920 * 1080. 4) You might have seen this resolution in your computer settings too. 5) Example: Image size(resolution)= 1000*750 then what is the total pixels? • Total pixels = 1000*750                         = 7,50,000 pixels • Total memory Bytes= 7,50,000*3                                        = 22,50,000 Bytes Which is equivalent to 2.25MB • Now you might think why we have multipled the total pixels with 3, because as I mentioned in pixel topic that to represent one pixel we require total 3 Bytes of