Vector Scan Display

-

 • 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.


7)  As shown in Fig., vector scan CRT display directly traces out only the desired lines on CRT i.e. If we want a line connecting Point A with Point B on the vector graphics display, we simply drive the beam deflection circuitry, which will cause beam to go directly from Point A to B. 

8) If we want to move the beam from point A to Point B without showing a line between points, we can blank the beam as we move it.

9) To move the beam across the CRT, the information about both, magnitude and direction is required. This information is generated with the help of vector graphics generator.

10) In vector displays beam is deflected from end point to end Point, hence this technique is also called random scan. In this the picture can be draw in terms of line, one at a time. The refresh rate depends on the number of lines to be displayed.

11) Let's see Advantage and disadvantage of Vector Scan Display 

1) Advantage

• High resolution then Raster scan Display

=> Because Vector Scan Display only focuses on drawing in particular region only rather than whole screen.

• produces smooth line.

=> This is something why Vector Scan Display is use for.

• Needs less memory to store picture definition.

=> Because it only stores points and coordinate information only 

2) Disadvantage

• Can't draw Realistic image

=> Because as we saw earlier it only stores information of coordinate not about colors that is picture Element (pixel)

• Limitation on color to be displayed

=> Particularly uses only 4 colors.


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

 

 

Comments

Post a Comment

Popular posts from this blog

Shadow Mask technique

-
Image
  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) Th e 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 elect
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

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 difference because pixel are very c
Read more