Biometric Sensors – Types and Its Working

The word biometrics is derived from the Greek words bio and metric. Where bio means life and metric means to measure. Biometrics are used to identify his or her physical and behavioural characteristics of a person. This method of identification is chosen over traditional methods, including PIN numbers and passwords for its exactness and case sensitiveness. Based on the designing, this system can be used as an identification system or authentication system. These systems are divided into various types which include vein pattern, fingerprints, hand geometry, DNA, voice pattern, iris pattern, signature dynamics and face detection. This article discusses what is a biometric sensor, different types of biometric sensors and its working.

Biometric Sensors
Biometric Sensors

Biometric Sensor

A biometric sensor is a transducer that changes a biometric treat of a person into an electrical signal. Biometric treats mainly include biometric fingerprint reader, iris, face, voice, etc. Generally, the sensor reads or measures light, temperature, speed, electrical capacity and other types of energies. Different technologies can be applied to get this conversation using sophisticated combinations, networks of sensors and digital cameras. Every biometric device requires one type of sensor. The biometrics applications mainly include: used in a high definition camera for facial recognition or in a microphone for voice capture. Some biometrics is specially designed to scan the vein patterns under your skin. Biometric sensors are an essential feature of identity technology.

Biometric Device
Biometric Device

Types of Biometric Sensor

Biometric sensors or access control systems are classified into two types such as Physiological Biometrics and Behavioral Biometrics. The physiological biometrics mainly include face recognition, fingerprint, hand geometry, Iris recognition, and DNA. Whereas behavioral biometrics include keystroke, signature and voice recognition. For a better understanding of this concept, some of them are discussed below.

Types of Biometric Sensor
Types of Biometric Sensor

Fingerprint Recognition

Fingerprint Recognition includes taking a fingerprint image of a person and records its features like arches, whorls, and loops along with the outlines of edges, minutiae, and furrows. Matching of the Fingerprint can be attained in three ways, such as minutiae, correlation, and ridge

  • Minutiae based fingerprint matching stores a plane includes a set of points and the set of points are corresponding in the template and the i/p minutiae.
  • Correlation-based fingerprint matching overlays two fingerprint images and the association between equivalent pixels is calculated.
  • Ridge feature-based fingerprint matching is an innovative method that captures ridges, as minutiae-based fingerprint capturing of the fingerprint images is difficult in low quality.
Fingerprint Recognition
Fingerprint Recognition

To capture the fingerprints, present methods employ optical sensors that use a CMOS image sensor or CCD; solid-state sensors work on the principle of transducer technology using thermal, capacitive, piezoelectric sensors or electric field ; or ultrasound sensors work on echography in which the sensor sends acoustic signals through the transmitter near the finger and captures the signals in the receiver. The scanning of the fingerprint is very stable and also reliable. It safeguards entry devices for building door locks and access of computer network are becoming more mutual. At present, a small number of banks have initiated using fingerprint readers for approval at ATMs.

Face Recognition

A face recognition system is one type of biometric computer application that can identify or verify a person from a digital image by comparing and analyzing patterns. These biometric systems are used in security systems. Present facial recognition systems work with face prints and these systems can recognize 80 nodal points on a human face. Nodal points are nothing but endpoints used to measure variables on a person’s face, which includes the length and width of the nose, cheekbone shape, and eye socket depth.

Face Recognition
Face Recognition

Face recognition systems work by capturing data for the nodal points on a digital image of a person’s face and resulting data can be stored as a face print. When the conditions are favorable, these systems use face prints to identify accurately. Currently, these systems focus on smartphone applications which include personal marketing, social networking, and image tagging purposes. Social sites like FB uses software for face recognition to tag the users in photographs. This software also increases marketing personalization. For instance, billboards have been designed with integrated software that recognizes the ethnicity, gender and estimated age of onlookers to deliver targeted marketing.

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Iris Recognition

Iris recognition is one type of bio-metric method used to identify the people based on single patterns in the region of ring-shaped surrounded the pupil of the eye. Generally, the iris has a blue, brown, gray or green color with difficult patterns that are noticeable upon close inspection. Please follow the below link to know more about iris recognition technology. Please follow the link to know more about IRIS Recognition Technology.

Iris Recognition
Iris Recognition

Voice Recognition

Voice recognition technology is used to produce speech patterns by combining behavioral and physiological factors that can be captured by processing speech technology. The most important properties used for speech authentication are nasal tone, fundamental frequency, inflection, cadence. Voice recognition can be separated into different categories based on the kind of authentication domain, such as a fixed text method, in the text-dependent method, the text-independent method, and conversational technique. Please follow the link to know more about Voice Recognition technology.

Voice Recognition
Voice Recognition

Signature Recognition

Signature recognition is one type of biometric method used to analyze and measure the physical activity of signing like the pressure applied, stroke order and speed. Some biometrics are used to compare visual images of signatures. Signature recognition can be operated in two different ways, such as static and dynamic.

Signature Recognition
Signature Recognition

In static mode, consumers write their signature on paper, digitize it through a camera or an optical scanner. This system identifies the signature examining its shape.

In dynamic mode, consumers write their signature in a tablet which is digitized, which obtains the signature in real-time. Another option is gaining by means of stylus-operated PDAs. Some biometrics also operate with smart-phones with a capacitive screen, where consumers can sign using a pen or a finger. This type of recognition is also known as “on-line”.

Thus, this is all about biometric sensors which can be used by several organizations to increase the level of security and also to protect their data and copyrights. We hope that you have got a better understanding of this concept. Furthermore, any doubts regarding the concept or electrical and electronics projects. Please comment in the comment section below. Here is a question for you, what are the applications of biometric sensors?

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