A touchless touchscreen uses optical pattern recognition and a solid state optical matrix sensor to detect hand movements in front of the screen instead of requiring physical contact. The sensor is made up of a matrix of pixels, each with photodiodes that convert incoming light to electric charge. The sensor generates signals that are processed by a digital image processor to provide output and interpret gestures without the user touching the display. Touchless touchscreens offer advantages like not wearing down the screen surface and allowing control from a distance, though sightline remains a limitation currently. The technology continues developing with potential for full body control of devices in the future.

1. - Saptarshi Dey,
CSE, 3rd Year,
MCKVIE

2. Touchscreen…..
A Quick Recap
 A touchscreen is an electronic visual display that the
user can control through simple or multi-touch gestures
 Can be controlled by fingers or by a special styles/pen Common in devices such as game consoles, Pcs,mobiles,etc.

3. TouchSensor
Controller
Software Driver

4. Problems faced by
touchscreen users

6.  In Touchless Touchscreen the there is no physical contact between the user and the
device
 It works by detecting hand movements in front of it.

7.  This is based on optical pattern recognition using a solid state optical
matrix sensor
 This sensor is then connected to a digital image processor, which
interprets the patterns of motion and outputs the results as signals

8.  In each of these sensors there is a matrix of pixels
 Each pixel is coupled to photodiodes incorporating charge storage regions.

9. Moving
Images in front
of the sensor
Detected by
the sensor
Light enters to
the sensor and
hits the pixel
matrix
The photodiodes
inside the pixel
converts incoming
light into electric
charge
The sensor
generates
electric signals
Signals are
processed by a
DIP to provide
output to the
devices

15. Advantages
 No de-sensitization of screen
 Can be controlled from a distance
 Useful for physically handicapped people
Drawbacks
 Not much, except the line of sight

16.  Touchless Technology is still developing
 Many Future Aspects
 With this in few years our body can become a
input device