This document describes a major project to create a persistence of vision (POV) display using an array of LEDs rotated at high speed by a motor. The project will use a microcontroller to control an LED driver chip and synchronize the LEDs to display 2D or 3D messages. Hardware components include an ATmega644 microcontroller, motor/driver system, sensor circuit, LED driver chip, and LED array. Software includes Keil for programming and Proteus for simulation. The POV display can be used for advertising, education, entertainment and animation by taking advantage of the visual persistence of the human eye.

1. FACULTY OF ENGINEERING
(Affiliated to Kurukshetra University)
CHIRAO, KARNAL
HARYANA
Persistence of Vision
MAJOR PROJECT SYNOPSIS
BACHELOR OF TECHNOLOGY
Electronic and Communication Engg.
Session-2010-2013
SUBMITTED TO: SUBMITTED BY:
Er. RAHUL PANWAR SOURABH (7910476-L)
( HOD ECE & Project Head)

2. Objective:-
Our project focuses on meeting the tremendous growth of advertisement. Persistence of vision
(POV) provides a unique technique to display our messages for advertising in an efficient way
and proper utilization of provided space. It is much more attractive than LCD displays or dot
matrix displays for displaying messages.
Description of Project:-
1.Microcontroller: The microcontroller will act as an SPI master. It will communicate to the
LED driver via SPI bus. It will send serial commands to write the registers on the LED driver
chips.
2.LED driver: The LED-driver controls the functioning of LED array and provides the
desired switching of LEDs.
3.LED Array: It is an array of LED that will turn on/off according to the message to be
displayed. It displays the message in 2-D or 3-D pattern.
4.Motor/Driver System: This will provide the facility to rotate the onboard circuit up to the
desired speed that is sufficient for the principle of Persistence of Vision.
5.Power Supply: The power supply unit provides the power to microcontroller, led driver and
motor/driver system.
6.Sensor circuit and controller: To collect the RPM data needed for timing calculations,
the microcontroller is connected to a sensor circuit board. This circuit will sense the rotation and
will provide the information about the revolution per second.
Definition of Project:-
1.Persistence of Vision: “Persistence of Vision” refers to the phenomenon where the retina
retains an image for a brief split-second after the image was actually seen, and lends itself to
animation by fostering the illusion of motion when we view images in closely-timed sequence to

3. one another. We don’t notice the fractional skips between images because that persistence fills in
the momentary gap to make the motion seem seamless.
2. POV Displays: A class of display device described as “POV” is the one that composes an
image by displaying one spatial portion at a time in rapid succession (for example, one column
of pixels every few milliseconds). A two dimensional POV display is often accomplished by
means of rapidly moving a single row of LEDs along a linear or circular path. The effect is that
the image is perceived as a whole by the viewer as long as the entire path is completed during the
visual persistence time of the human eye. A further effect is often to give the illusion of the
image floating in mid-air. A three dimensional POV display is often constructed using a 2D grid
of LEDs which is swept or rotated through a volume.
Block Diagram:-
Working:
Rotation of single LED with high speed in circular motion gives the appearance of complete
circle due to the persistence of vision. It forms a matrix and the resolution of message depends
on the speed. The single element shows a pixel of the matrix. This idea can be extended to rotate
a line of number of LEDs and thus create a display of letters or numbers. Now depending on
what has to be displayed, the LEDs are synchronised and the required message is displayed in
two dimensions.
Flow Diagram

4. Details of hardware Components and software being used:
Hardware used:

5. 1 Microcontroller ATMEGA644:
It is an 8-bit AVR RISC-based microcontroller with 64 k byte in system programmable flash. It
will send commands to write the registers on the LED driver.
2. Motor/driver system:
The motor/driver system is rotated at a particular speed which will provide the speed required for
persistence of vision (POV).
3. Sensor circuit and controller:
It will sense the speed and trigger the interrupt the controller. Controller will provide the
information of rpm of motor.
4. LED driver (MAX6966):
It acts as a SPI slave. It has 10 output pins and an SPI input bus. It can control 3 RGB LEDs.
Each pin on MAX6966 chip can be chosen to turn on or off a colour for a specific LED.
5. LED array:
It contains a number of LEDs aligned in a particular pattern, which when derived by the motor
forms a matrix and will display the desired message.
Software used:
6.2.1 Keil: Keil software is used for programming of microcontroller and to connect the
microcontroller to the LED driver through SPI interfacing. The programming is done in
embedded C.
6.2.2 Proteus: Proteus simulator is used for the simulation process.
TIME&COST
1.TIME ESTIMATED FOR COMPLETION OF PROJECT:
RESEARCH PHASE - Two months

6. DESIGN PHASE - Three months
DEVELOPMENT – Two months
TESTING – One month
2. COST
Estimated cost of the project is Rs.4000-5000.
Advantage:-
The more attractive the message will be, the more people will get influenced by it. The main
motive of our project is to make the advertising media an effective one. Following are the areas
in which POV plays a unique role:
ADVERTISING
EDUCATION
ENTERTAINMENT
ANIMATION
PROPELLER CLOCK
TOYS AND GAMES
MALLS
3-D DISPLAY
SCOPE:
1.Advertisement: In this modern era there is a growing need of advertising the products &
services. People get influenced by good advertisement. Persistence of vision proved to be a very
effective method for providing a visual image to attract the consumers. Advertisement can be
made much more attractive by two dimension or three dimension visual image.
2. Entertainment: Persistence of vision plays a very vital role in entertainment point of view. It
can be used in shopping malls for displaying messages. It can also be used in film industry.
Motion pictures are based on the principle of persistence of vision. The display is like any
complex toy .We can make it for fun and diversion by using this application in games and toys.

7. 3.Animation: The Persistence of vision is the basic principle of animation. This technique is also
used in cartoon animation. Cartoon movies are also the result of persistence of vision.
4.Education: If Persistence of vision is used in education field it will provide a better way for
interactive education. Many concept need to be explained in three dimension view that can be
easily demonstrated by the help of this persistence of vision.
Conclusion:
As it is, this pyro propeller clock POV turned out exactly as I had hoped. It is just simple enough,
that I feel people can duplicate it with much less perspiration than it took me to build it, yet it
still achieves the desired POV effect that looks so cool. However, the simplistic design has its
trade-offs; especially in terms of reliability. The system created here could only run for a few
hours before the 9v battery died, making this more of a novelty project. But if you are trying to
build your own propeller clock POV for fun, then novelty is what it is all about!
Reference:
http://people.ece.cornell.edu/land/courses/ece4760/FinalProjects/s2012/jm787_dab355/jm787_dab355/in
dex.html
http://liudr.wordpress.com/2011/04/03/persistence-of-vision-2/
http://courses.engr.illinois.edu/ece445/projects/spring2011/project6_proposal.pdf
http://animation.about.com/od/glossaryofterms/g/pervision_def.htm
https://www.google.co.in/search?q=persistence+of+vision+iit+kanpur&oq=persistence+of+vision+iit+ka
npur&sugexp=chrome,mod=0&sourceid=chrome&ie=UTF-8
http://www.siliconindia.com/aiepic/project/persistence_of_vision_display-pid=2594.html
http://www.techlink.org.nz/student-showcase/electronics/images/Logan-spinning-led-display.pdf