This document contains information about an LCD display presentation created by the Creative Buzz group. It includes sections on the introduction to LCD displays, the history of LCDs which were invented in 1968, how LCDs work using liquid crystals, the Bresenham line algorithm for drawing lines in computer graphics, advantages and disadvantages of LCDs, and applications of LCDs such as in devices like clocks, calculators, televisions and computer monitors.

1. w
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C
O
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Group name
Creative Buzz

2. DEDARUL ALAM(152-15-6000)
TONMOY SHAHA OPI(152-15-5932)
MD. MAHBUB ALAM(152-15-5991)
SHISHIR AHMED(152-15-5927)
MD.NUR-UN NABI BIPLAB(152-15-5963)
S.M. ZAHIDUL ISLAM(152-15-5925)

4. Presentation
Layout
 Introduction
 History
 LCD
 Bresenham
Algorithm
 Advantages
 Disadvantages
Comments
 References

5. Introduction
LCD is commonly used in small systems, such as
calculators, and portable, laptop, computers.
These non-emissive devices produce a picture by
passing polarized light from the surroundings or
from an internal light source through a liquid-
crystal material that can be aligned either block
or transmit the light.

6. HISTORY OF LCD
George H. Heilmeier
Liquid Crystal Display (LCD) Invented 40
Years Ago. In May 1968, electrical
engineer George H. Heilmeier and his
team of scientists revealed the liquid
crystal display to the public. The
technology that is seen on computers,
alarm clocks and the digital screens of
microwaves is ubiquitous.
HOW IT WORKS ?
The pixels are controlled in completely different ways in
plasma and LCD screens.

7. What IsLCD
• Aliquid crystal display (LCD)is athin, flat panel used for
electronically displaying information such astext, images,and
moving pictures.
• It is an electronically-modulated optical devicemade up of
any number of pixels filled with liquid crystals and arrayed in
front of alight source(backlight) or reflector to produce
images in color ormonochrome.
• Its uses include computer monitors ,televisions , instrument
panels, and devices ranging from aircraft cockpit displays, to
every-day consumer devices such asclocks , calculators, and
telephones.

8. Liquid crystal display
Liquidcrystal display (LCD)is a flat electronicdisplay panel used as a
visual display aid. It uses liquid crystals to create visual effects on
screen. Liquidcrystal is a state of matter between solids and liquids.
LCDsdo not generatelight on their own but rely on sunlight or room
light to generateimages with help of liquid crystal.

9. How Lcd works

10. 8
Types of lcds
• Passive vs ActiveMatrix
– Passive
• Each pixelmust retainit’sstate without a steady electric charge
• Scanned one pixel at atime
• Poor contrast,and very slow responsetimes
– Active
• Electric charged is stored betweenrefreshes
• Scanned one row at atime

11. Advantages of
LCD
Brightness
Physical
Thin, with a
small
footprint
Geometric
Distortion
Low power
consumption
Sharpness

12. Disadvantages of LCD
Resolution Interference
Viewing
Angle
Black-
Level,
Contrast
and Color
Saturation
White
Saturation Aspect
Ratio
Cost

13. Applications
of LCD
Clocks,Watches, Calculators
Cameras: Used in digital cameras for
displaying images
Television: Has a major application in LCD
TFT screens
Computer monitors: Most of the modern
world computer monitors are made of LCDs
Instrument panels: All the lab instruments
uses LCD screens for display
Aircraft cockpit displays: Cockpit display
panels of pilots are usually LCDs
Video players: Such screens are very popular
in video game parlours and consoles

15. History
The Bresenham line algorithm is an algorithm which determines
which order to form a close approximation to a
straight line between two given points.
Bresenham's line algorithm is named after Jack Elton Bresenham
who developed it in 962 at IBM.
It is one of the earliest algorithms developed in the field of
Computer Graphics
Bresenham's algorithm was later extended to produce circles, the
resulting algorithms being 'Bresenham's circle
algorithm and Midpoint Circle Algorithm

16. Step 1:Input line endpoint (x1,x2) and (x2,y2).
Step 2: calculate constants..
Δx=x2-x1
Δy=y2-y1
2Δy
2Δy-Δx
Step3:Assign value to the starting parameters
K=0
P0=2Δy-Δx
Step4:Plot the pixel at (x1,y1)

17. Step5:For each integer x-coordinate xk ,
along the line
If
pk<0 plot pixel at (xk+1,yK)
P(k+1)=pk+2Δy
Else
plot at (xk+1,yK+1)
P(k+1)=pk+2Δy- 2Δx

18. In General Math Rules:
Xk+1, y k
pk+1= p + 2dyi
Else
Note: For |m| ≤ 1 the constants 2dy and 2(dy-dx) can be calculated
once,
.
If Po<=0 then
Plot pixel at
Plot pixel at
X ,Yk+1, k
k+1P =k
P +2dy+2dx

19. Example – Draw a line from (20,10) to (30,18)
19
18
17
16
15
14
13
12
(20,10)
(30,18)
dx = 10
dy = 8
initial decision d = 2dy – dx = 6
Also 2dy = 16, 2(dy – dx) = -4
0
i di
(xi+1
,yi+1)
0
1
2
3
4
5
6
7
8
9

20. Example – Draw a line from (20,10) to (30,18)
19
18
17
16
15
14
13
12
(20,10)
(30,18)
dx = 10
dy = 8
initial decision d = 2dy – dx = 6
Also 2dy = 16, 2(dy – dx) = -4
0
i di
(xi+1
,yi+1)
0 6 (21,11)
1 2 (22,12)
2 -2 (23,12)
3 14 (24,13)
4 10 (5,14)
5 6 (26,15)
6 2 (27,16)
7 -2 (28,16)
8 14 (29,17)
9 10 (30,18)

21. Advantage of brasenham
• An fast incremental algorithm
• Uses only integer calculations
• Bresenham's algorithm is more speedy
• Bresenhams line algorithm the new pixel is calculated
with a small unit change in one direction and checking
of nearest pixel with the decision variable satisfying the
line equation

22. Disadvantage
• basic line drawing algorithm
• "advanced" topic of antialiasing isn't part of Bresenham's
algorithm
• Causes stair-case pattern
• Lacking of smoothness

23. Example
K PK (x,y)
0 6 21,11
1 2 22,12
2 -2 23,12
3 14 24,13
4 10 25,14
5 6 26,15
6 2 27,16
7 -2 28,16
8 14 29,17
9 10 30,18
End points (20,10) and (30,18)

24. Application and comment
• determines the points of an n-dimensional raster
• draw line primitive in a bitmap image
• An extension of this algorithm use for circle drawing
• Graphics card
• 2-d line drawing
Comment:
The label "Bresenham" is used today for a family of
algorithms extending or modifying Bresenham's original
algorithm.

25. References:
www.polytechnichub.com/advantages-disadvantages-lcd-liquid-crystal-display/
https://www.quora.com/Computer-Monitors-and-Screens-LED-vs-LCD-Which-
one-is-better
www.google.com/search?q=application+of+lcd
http://www.zseries.in/electronics%20lab/displays/lcd/#.W-Hp6pMzaUk
https://en.wikipedia.org/wiki/Bresenham%27s_line_algorithm