Douglas Engelbart invented the computer mouse in 1964 to facilitate graphical user interfaces and pointing on digital displays. The mouse uses an optical or mechanical system to detect movement over a surface and translate it to on-screen cursor movement. It consists of a ball or optical sensor, buttons, and an electronic circuit board that encodes motion data for transmission to and interpretation by the connected computer. Modern mice use optical sensors rather than mechanical components, improving durability and versatility.

1. Computer Mouse

2. S.N.COLLEGE , GADHINGLAJ
Invention of Mouse
• Douglas C. Engelbartinvented several
interactive, user-friendly device such
as the computer mouse, windows,
computer video teleconferencing,
hypermedia, GroupWare, email, the
Internet and more.
• In 1964, the first prototype computer
mouse was made to use with a
Graphical User Interface (GUI),
'windows'.

3. S.N.COLLEGE , GADHINGLAJ
Invention of Mouse
• Engel Bart received a patent for the wooden shell with two metal
wheels (computer mouse) in 1970, describing it in the patent
application as an "X-Y position indicator for a display system."
• Mice come in various shapes and sizes and from different
manufacturers but the most target manufacturers are Microsoft
and Logitech.

4. S.N.COLLEGE , GADHINGLAJ
Invention of Mouse
• The Mouse consists of different components as follows.
–A housing that you hold in your hand and move around on your
desktop.
–A roller ball that rotates as you move the mouse
–Several buttons to make selections.
–A cable for connecting mouse to the PC
–An interface connector to attach the mouse to the PC

5. S.N.COLLEGE , GADHINGLAJ
Mouse Interface Types
• There are many ways that mice and trackballs are interfaced to
a computer which are as follows:
–Bus
–Serial
–PS/2
–USB

6. S.N.COLLEGE , GADHINGLAJ
Mechanical Mouse Working
• A ball inside the mouse
touches the desktop and
rolls when the mouse
moves

7. • The underside of the
mouse's logic board.
• The exposed portion of
the ball touches the
desktop

8. S.N.COLLEGE , GADHINGLAJ
Mechanical Mouse Working
• Two rollers inside the mouse • The following image
touch the ball. shows the two white
• One of the rollers is oriented so rollers on this mouse
that it detects motion in the X
direction
• The other is oriented 90
degrees to the first roller so it
detects motion in the Y
direction.
• When the ball rolls, one or both
of these rollers roll as well.

9. S.N.COLLEGE , GADHINGLAJ
Mechanical Mouse Working
• The rollers each connect to
• The following image
a shaft, and the shaft spins shows the disk:
a disk with holes in it.
• When a roller rolls, its shaft
and disk spin.
• A typical optical encoding
disk.

10. • This disk has 36 holes
around its outer edge.

11. S.N.COLLEGE , GADHINGLAJ
Mechanical Mouse Working
• On either side of the disk there is an infrared LED and an
infrared sensor. The holes in the disk break the beam of
light coming from the LED
• The infrared sensor then sees pulses of light.
• The rate of the pulsing is directly related to the speed of the
mouse and the distance it travels.

12. S.N.COLLEGE , GADHINGLAJ
Mechanical Mouse Working
• A close-up of one of
the optical encoders
that track mouse
motion.

13. • There is an infrared LED (clear) on one side of the disk and an
infrared sensor (red) on the other

14. S.N.COLLEGE , GADHINGLAJ
Mechanical Mouse Working
• An on-board processor chip
reads the pulses from the
infrared sensors and turns them
into binary data that the
computer can understand.

15. • The chip sends the binary data to the computer through
the mouse's cord

16. S.N.COLLEGE , GADHINGLAJ
Mechanical Mouse Working
• The logic section of a mouse is dominated by an encoder chip
• It’s a small processor that reads the pulses coming from the
infrared sensors and turns them into bytes sent to the computer.
• Two buttons that detect clicks(on either side of the wire
connector).
• Almost all mice used on personal computers use this opto
mechanical arrangement.

17. S.N.COLLEGE , GADHINGLAJ
Mechanical Mouse Working
• The disk moves mechanically, and an optical system
counts pulses of light.
• Each encoder disk has 2 infrared LED's and 2 infrared
sensors, one on each side of the disk (so there are four
LED/sensor pairs inside a mouse).
• This arrangement allows the processor to detect the disk's
direction of rotation.
• There is a piece of plastic with a small, precisely located hole
that sits between the encoder disk and each infrared sensor.

18. S.N.COLLEGE , GADHINGLAJ
Mechanical Mouse Working
• This piece of plastic
provides a window
Plastic
sheath
through which the
infrared sensor can
"see".

19. • The window on one side
of the disk is located
slightly higher than it is
on the other
• One half the height of one of the holes in the encoder disk, to be
exact.

20. S.N.COLLEGE , GADHINGLAJ
Mechanical Mouse Working
• That difference causes the two infrared sensors to see
pulses of light at slightly different times.
• There are times when one of the sensors will see a pulse of light
when the other does not, and vice versa.

21. S.N.COLLEGE , GADHINGLAJ
Optical Mouse
• Early mice made by Mouse Systems and
a few other vendors used a sensor that
required a special grid-marked pad and
the need to use them with a pad caused
them to fall out of favor.
• Microsoft's IntelliMouse Explorer
pioneered the return of optical mice
using optical technology to detect
movement, and it has no moving parts
itself (except for the scroll wheel and
buttons on top).

22. S.N.COLLEGE , GADHINGLAJ
Optical Mouse
• Done by upgrading the optical sensor from the simple type
used in older optical mice to a more advanced CCD (charge
coupled device) which essentially is a crude version of a video
camera sensor that detects movement by seeing the surface
move under the mouse.
• Versatility and low maintenance make optical mice an
attractive choice and the variety of models available from both
vendors means you can have the latest optical technology for
about the price of a good ball-type mouse.

23. S.N.COLLEGE , GADHINGLAJ
Trackball
• A trackball is comparable to a mechanical mouse in operation.
• In the trackball, instead of moving the mouse to roll the ball, you
actually roll the ball yourself with your hand.
• Ball’s motion is translated into motion in the X -direction and the
Y-direction, and any movement is transmitted to the PC for
processing which is used in Laptop.

24. S.N.COLLEGE , GADHINGLAJ
Trackball

25. S.N.COLLEGE , GADHINGLAJ
Infrared Wireless Mouse
• Most mice are attached to the serial port via a cable, some mice
use infrared transmission to send the codes to a receiver that is
attached to your serial port.
• Infrared mice are cordless in that they do not have a cable that
attaches the mouse portion to the serial port.
• As the infrared light cannot pass through objects it requires an
infrared mouse to be in direct line of sight with the receivingunit
connected to the PC.

26. S.N.COLLEGE , GADHINGLAJ
Infrared Wireless Mouse

27. Design & Published by:
S.N.Education Group,
Opp- Govt Rest House,
Kadgaon Road,
Gadhinglaj.