Shadow Mask technique

-

 1) Shadow Mask technique is used in Raster Scan Display and produces wide range of colour, which wasn't possible in Beam penetration technique.


2) Here on the screen we have 3 dots of each color which means one pixel has three value of color i.e RGB which can create many different shades of color.

3) So in this technique we have 3 electron gun's which are assigned for there respective color RGB and one more most important thing that is a grid just behind the screen which is known as "Shadow Mask Grid".

4) Shadow mask grid is pierced with small round holes in a triangular pattern.

5) The 3 electron beams are deflected and focused as a group onto the shadow mask, which contains a sequence of holes aligned with the phosphor- dot patterns.

6) There is one gun for each of 3 Color RGB.


7) when these three colors mixed together can create all the colors we see on the screen, but remember these gun don't shoot the bullets instead they shoot a powerful beam of electrons towards the face of monitor.


8) Special chemical phosphore are painted on the inside of the monitor, energy from the electrons beams makes the individual phosphore glow either red, blue or green depending on the type of phosphore.


9) The stronger the electron beam the brighter the phosphore glow.


10) A sheet of metal with holes in it helps to keep the electron beam aligned exactly with the phosphore this is called the Shadow Mask.




11) Let's see the Advantage and disadvantage of Shadow Mask technique.

A) Advantage

• Realistic image

• Million different colors to be generated

B) Disadvantage

• Relatively expensive compared with the monochrome CRT

• Relatively poor resolution

• Convergence Problem

*You can leave a comment if you have doubt in it.

Comments

Post a Comment

Popular posts from this blog

Line Basic Concepts

-
Image
 • We are going to study about Line Basic Concepts on Raster Screen. • so we are going to discuss what are the different ways in which line can be represented on Raster Screen and some of there respective features. 1) Vertical and Horizontal Line  • They have same width. • Straight line.  • Effective spacing is less. • More brighter. 2) 45° Line  • Width is not a constraint.  • Straight line. • More effective spacing. • Less brighter. Explanation:  • Point to remember is when there is more spacing between the points of line less brighter it will be and vice versa.  • But more spacing leads to effectiness in orientation of line. 3) Line with other orientation • In both of the above image the lines are nethier straight nor of same width. • Here points of line that is Pixel is approximated because while drawing the single line at point we get two points one is above the line and another is below the line. • But here approximation doesn't make a wide diffe...
Read more

Sample programs

-
Image
 • We are going to discuss some simple programs in turbo C before going to graphics program that is terminal in graphic mode. • So simple programs in text mode. 1) Program to print Hello world on different line. #include<stdio.h> #include<conio.h> int main() {     int c= 5;      for(int i=0;i<12; i=i+2)     {     gotoxy(c,i);     printf("Hello world!");     c=c+2;     } getch(); return 0; } Explanation: • we have also discussed prior about text mode in Turbo C let's understand it in short. • So this is the image representation of text mode where: 1) screen is divided in Rows and Columns. 2) we have 80 rows and 25 columns 3) Here first coordinate is of column and another is row example: (80,25) • 80 is column and 25 is row only in turbo C text mode it's reverse as it is normally. 4)  program we did above is of Controlling the cursor with the help of function gotoxy( )  it's a functio...
Read more

Types of Computer Monitor

-
Image
 • 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.
Read more