The document discusses virtual keyboards, which allow users to communicate with computers through a projected image of a keyboard on a flat surface. It outlines the technology's invention, components, working mechanism, as well as its advantages and disadvantages. The document highlights various types of virtual keyboards, including their applications and challenges in usage.

1. Department of Presented By:
MCA Siddhartha Sadhukhan
And
Siddhartha Banerjee

2. Introduction
 A virtual keyboard allows a user to communicate with
computer.
 Virtual keyboard is a technological breakthrough.
 Virtual keyboard is well suited with today’s computer
trend.
 Easy for bi- or multi-lingual users .
 Modern virtual keyboards display a projection of a
image of a keyboard and allow type on it.
 The Virtual Keyboard is not restricted to the QWERTY
touch-typing paradigm.

3. Overview
 An optical virtual keyboard was invented and patented by
IBM engineers in 1992.
 Virtual Keyboards is a flashlight-size gadget that projects
an image of a keyboard on non-reflexive surface.
 It uses sensor technology and artificial intelligence.
 The device detects movement of fingers, and make the
proper key-stroke.

4. Modules
The virtual keyboard system comprise of three module:
 The sensor module:
 Serves as the eyes of the Keyboard Perception technology.
 This module determines the appropriate
key-stroke and generates the
corresponding code and it to the host
device.

5.  IR-light source
 Emits invisible infrared beam.
 The Infrared Light Source emits a beam of infrared light
and overlap the area on which keyboard
is projected.
 This helps in recognizing the hand
movements and the pressing of keys.

6.  The pattern projector
 Projects an image of the keyboard on any flat-surface.
 The Projector has wide-angle lens so
that a large pattern can be projected
from relatively low distance.
 The template serves only as a
reference for the user and is not involved
in the detection process

7. Working Mechanism
 Step 1: A image of a keyboard is projected.
 Step 2: An infrared plane of light is generated just above
the projection keyboard.
 Step 3: Finger movement breaks the infrared plane and
reflects light beam which is picked up by a CMOS chip.

8. Other Types of VKB
 Canesta
 Projection of a keyboard.
 Allow work on that projection.
 Small in size.
 Kitty
 Developed at the University of California
in Irvine.
 Wearable "virtual" keyboard.
 Using spiraling, printed-electric circuit wires that
wrap around the fingers detects key-stroke.
 On-screen Keyboard
 It is a software component.
 It can usually be operated with
multiple input device

9.  Advantages
 Can be projected on any non-reflective surface.
 Create low noise.
 Not restricted to the QWERTY touch-typing paradigm.
 Highly portable.
 Free from hardware based key-logger.
 Disadvantages
 Hard to use.
 Very costly.
 The room where we use vkb should not be very bright.
 Without the feel of the keys slowing you down and possibly
even creates a inaccurate document.
 The IR light is affected by sunlight.
 Alignment needed between IR transmitter and IR detector.

10. References
 https://en.wikipedia.org/wiki/Computer_keyboard
 https://en.wikipedia.org/wiki/Virtual_keyboard
 https://en.wikipedia.org/wiki/Projection_keyboard
 http://www.howtechnologywork.com/virtual-laser-keyboard/
 http://www.extremetech.com/extreme/51958-canesta-says-virtual-
keyboard-is-reality
 https://www.siggraph.org/s2003/conference/etech/everyday.html
 http://electronics.howstuffworks.com/gadgets/travel/virtual-laser-
keyboards.htm
 http://www.virtual-laser-devices.com/demo.asp

11. Any Question ?

12. Thank
you