CHAPTER 7. HOW FINGERPRINT SCANNER WORKS.
About a decade before, whenever we watched spy moviesand other high tech movies we were
amazed to see the lock getting opened by fingerprintsand always wondered if we had such
technology to keep all our little secrets safe. Well,now after just 10 years, almost all of us have
such technology in our pocket safeguarding all oursecrets. Now even a low budget mobile
phone has a biometric locking system in it.So let’sreveal the secret behind this amazing
technology.
There are different types of fingerprint scannersthat are available today so let’s look into them
one by one.
1. Optical Scanners.
Optical scanners are one of the fundamental techniquesused to detect and compare
fingerprints. From the name, we can comprehend thatthe method uses optical images to
capture and detect unique patterns and ridges. Itbasically takes a photograph of the fingerprint
and by using a special algorithm detects a uniquepattern by comparing light and dark areas of
the image.
Now to take the image of the finger is not as easyas taking the photo through a smartphone
camera. The camera needs to be of high resolutionto capture the fine image of fingerprints also
they have high contrast that differentiates fine structure.As the distance between the finger and
the camera is minimal, they consist of a large numberof diodes per inch to capture closeups.
Also, it is very dark because the finger is
covering the area above the camera, so they
have a series of LEDs that lighten up the area
during the scanning process.
The major drawback of optical scanning is that
they are bulky and not very secure. It is easy to
fool it with some prosthetics as the images taken
are 2D. So can’t be trusted with the sensitives
details. Also, as technology is advancing each
day, there are many good alternatives to this in
the market.