Transcript IRIS/RETINA BIOMETRICS Retina The retina is a thin layer of cells at the back of the eyeball of vertebrates. It is the part.

IRIS/RETINA BIOMETRICS
Retina
The retina is a thin layer of cells at the back of the
eyeball of vertebrates.
It is the part of the eye which converts light into
nervous signals.
The retina contains photoreceptor cells (rods and
cones) which receive the light; the resulting neural
signals then undergo complex processing by other
neurons of the retina, and are transformed into
action potentials in retinal ganglion cells whose
axons form the optic nerve.
The retina not only detects light, it also plays a
significant part in visual perception.
In embryonal development, the retina and the
optic nerve originate as outgrowths of the brain.
The unique structure of the blood vessels in the
retina has been used for biometric identification.
To brain
Rods sense
brightness
Cones
sense color
The retina, in the
back of your eye, has
cells that are
sensitive to light.
They connect directly
to your brain.
Biometrics which analyze the
complex and unique characteristics
of the eye can be divided into two
different fields:
– iris biometrics - iris is the colored band
of tissue that surrounds the pupil of the
eye.
– retina biometrics - retina is the layer of
blood vessels at the back of the eye.
An iris recognition system uses a
video camera to capture the sample
while the software compares the
resulting data against stored
templates.
Understanding Iris Recognition
Iris scan biometrics employs the
unique characteristics and features of
the human iris in order to verify the
identity of an individual.
The iris is the area of the eye where
the pigmented or colored circle,
usually brown or blue, rings the dark
pupil of the eye.
Iris recognition systems use small, high-quality
cameras to capture a black and white highresolution photograph of the iris.
This process takes only one to two seconds and
provides the details of the iris that are mapped,
recorded and stored for future
matching/verification
Once the image is captured, the iris’ elastic
connective tissue—called the trabecular
meshwork—is analyzed, processed into an optical
“fingerprint,” and translated into a digital form.
Given the stable physical traits of the iris, this
technology is considered to be one of the safest,
fastest, and most accurate, noninvasive biometric
technologies.
The iris is differentiated by several characteristics
including ligaments, furrows, ridges, crypts,
rings, corona, freckles, and a sigzag collarette.
An Iris Reader
Iris
An Iris Recognition Process
The inner edge of the iris is located by an
iris-scan algorithm which maps the iris’
distinct patterns and characteristics.
Iris’ are composed before birth and,
except in the event of an injury to the
eyeball, remain unchanged throughout an
individual’s lifetime.
Iris patterns are extremely complex, carry
an astonishing amount of information and
have over 200 unique spots.
The fact that an individual’s right and left
eyes are different and that patterns are
easy to capture, establishes iris-scan
technology as one of the biometrics that is
very resistant to false matching and fraud.
The false acceptance rate for iris
recognition systems is 1 in 1.2 million,
statistically better than the average
fingerprint recognition system.
The real benefit is in the falserejection rate, a measure of
authenticated users who are rejected.
Fingerprint scanners have a 3 percent
false-rejection rate, whereas iris
scanning systems boast rates at the 0
percent level
Eyeglasses and contact lenses
present no problems to the quality of
the image and the iris-scan systems
test for a live eye by checking for the
normal continuous fluctuation in
pupil size.
Spoofing the Iris
The iris is extremely difficult trait to
spoof, yet there have been attempts
to do just that
Attacks on the iris fall into the
following categories:
– Attacking the physical iris
– Using artfacts
– Attacking the communication
– Compromising the teplate
– Attacking the fallback system
Advantages of the Iris for
Identification
Highly protected, internal organ of the eye
Externally visible; patterns imaged from a
distance
Iris patterns possess a high degree of
randomness
Changing pupil size confirms natural
physiology
Limited genetic penetrance of iris patterns
Patterns apparently stable throughout life
Encoding and decision-making are
tractable
Disadvantages of the Iris for
Identification
Small target (1 cm) to acquire from a
distance (1 m)
Moving target ...within another
Located behind a curved, wet, reflecting
surface
Obscured by eyelashes, lenses, reflections
Partially occluded by eyelids, often
drooping
Deforms non-elastically as pupil changes
size
Illumination should not be visible or bright
Some negative (Orwellian) connotations
Retinal Recognition System
Retina scans are performed by directing a low-intensity infrared
light to capture the unique retina characteristics.
An area known as the face, situated at the center of the retina, is
scanned and the unique pattern of the blood vessels is captured.
Retina recognition technology captures and analyzes the
patterns of blood vessels on the thin nerve on the back of the
eyeball that processes light entering through the pupil. Retinal
patterns are highly distinctive traits.
Every eye has its own totally unique pattern of blood vessels;
even the eyes of identical twins are distinct. Although each
pattern normally remains stable over a person’s lifetime, it can be
affected by disease such as glaucoma, diabetes, high blood
pressure, and autoimmune deficiency syndrome.
Retina biometrics is considered to be the best biometric
performers.
However, despite is accuracy, this technique is often thought to be
inconvenient and intrusive. And so, it is difficult to gain general
acceptance by the end user.
Eye and retinal scanner are ineffectual with the blind and those
who have cataracts.
The fact that the retina is small, internal, and difficult to
measure makes capturing its image more difficult than
most biometric technologies. An individual must position
the eye very close to the lens of the retina-scan device,
gaze directly into the lens, and remain perfectly still while
focusing on a revolving light while a small camera scans the
retina through the pupil.
Any movement can interfere with the process and can
require restarting. Enrollment can easily take more than a
minute. The generated template is only 96 bytes, one of
the smallest of the biometric technologies.
It is one of the most accurate and most reliable of the
biometric technologies, and it is used for access control in
government and military environments that require very
high security, such as nuclear weapons and research sites.
However, the great degree of effort and cooperation
required of users has made it one of the least deployed of
all the biometric technologies. Newer, faster, better retina
recognition technologies are being developed.