Access control and security - your face is your password

Facial recognition technology has gained significant attention over the fingerprint biometric, especially in consumer electronics (like smartphones) and security systems – for its contact-free, easy-to-use, fast-response security and accuracy advantages. Read on to understand how ams OSRAM ensures when your face is your password, that it is “spoof-proof”.


The use of facial recognition is gaining popularity. A significant proportion of biometric authentication is based on the properties (size, shape, position, etc.) of our unique combination of facial features like cheek bones, eyes, nose, mouth, lips, chin, jaw line, forehead, scalp and ears. Often facial recognition is used as one of multiple modes of authentication – on the basis that two ID authentication measures can further reduce false acceptance and rejection rates (FAR/FRR) – and so is growing in adoption. 

Advanced key-less access control solutions – whether to buildings, devices, confidential data, or even your money – use one or more biometrics like scanning a fingerprint, face, iris or the vein pattern of a hand. After the COVID-19 pandemic and now with the start of the yearly flu season, the trend goes more into contactless biometric scan options because they are better from a hygiene perspective. Typical solutions rely on 3D-imaging with adaptive illumination and presence sensing. While anti-spoofing technology, e.g. using 3D-scans, is essential to detect fake-presence. These innovative alternatives replace conventional numerically coded access based on optical-force sensing for touchpads (e.g. manually entered multi-digit keys).

Still there are four key challenges manufacturers are facing when designing today’s access control and security solutions:

  1. How to lower the risk of false positives and false negative outcomes for greater reliability and at faster detection speeds. 
  2. How to reduce system power saving: consider battery operated devices relied on for safe and secure access when required.
  3. Saving space at the system level: a tiny footprint enables facial authentication in small devices without limiting other design choices for manufacturers.
  4. Saving overall system costs.


To address these challenges, the ams OSRAM portfolio offers manufacturers a broad set of hardware components for realizing customer-oriented access control and security solutions, including some new market offerings and enhancements which we introduce below. 

ams OSRAM develops both advanced sensor and emitter technologies for many kinds of biometric authentication. Here, we focus on technologies supporting facial recognition, for example for all kinds of smart door locks, access terminals or credential readers. Each complete facial recognition system would normally require a choice out of three 3D scanning types (Structured Light, Stereo Vision, Active Stereo Vison), which are realized with cameras, IR illuminators, LED drivers, presence detection, ambient light sensing, plus optional decorative lighting.

We also offer the new reference design module Seres 5x Optical Frontend for 3D-Vision  – a flexible optical frontend solution for developing biometric access solutions, where ams OSRAM provides all optical components serving as a platform for advanced algorithmic access functions. This comprises our recommended combination of portfolio options in a vertically integrated system enabling customers and developers of biometric identification systems to seamlessly connect to optical front-end sensing hardware by ams OSRAM. One of our companions of our partner network, Teknique also contributes to this solution generic I/F adapter to the Amberella ISP and Ambarella-based 3D-Vision System SDK.
 


Achieving high-performance in facial recognition systems requires careful consideration and selection of advanced, high-quality components. Consider combining multiple devices, including image sensors, infrared LED illumination combined with LED Drivers, depth sensors (such as ToF), and infrared laser for illumination (dot projectors), to create a more comprehensive and accurate representation of facial features. 

 

IR Illumination & Drive Solution with State-of-the-art OSLON Black and SYNIOS P2720 IR Illumination with 920nm

Brighter IR illumination at the optimal 920nm wavelength enables the IR camera to capture a better image of a person, optimizing a necessary trade-off between sensor sensitivity and red glow. The human eye is slightly sensitive to short-wavelength IR light, resulting in a visible red glow. This red glow is much weaker at 920nm than at 850nm. Use of the 920nm wavelength means that the face recognition algorithm will operate better, enabling it to recognize an authorized user more reliably, and lowering the risk of FAR/FRR outcomes.

For facial recognition, advantages include better sensitivity at 940nm for a lower risk of false positive or false negative outcomes or alternatively reduced red glow at 850nm. 920nm is combining advantages, like good sensitivity and reduced red glow effect.

See here our infrared LEDs with new additional wavelength of 920nm: 
OSLON® Black SFH 4725AS
OSLON® Black SFH 4726AS
OSLON® Black SFH 4727AS
SYNIOS® P2720 SFH 4775S

Innovative two-channel LED/VCSEL driver with integrated boost converter and high output currents

The newly introduced AS1170 is a high-power LED/VCSEL/Laser driver and a perfect match to OSLON Black and SYNIOS P2720 IR LEDs. 
AS1170 can drive two output channels independently with up to 1000mA each or 2000mA in combined mode, with output current controllable via PWM. Automatic current adaption for low battery voltage and integrated safety functions further reduce development effort for implementation of these features into end devices. 
For light sources which need a higher supply voltage, the AS1170 features a highly efficient 4 MHz fixed frequency boost converter, requiring only a small and cost effective 1µH external inductor to provide 5.5V.
With its small wafer-level chip-scale package footprint, the AS1170 is therefore designed to meet the challenges of system power saving, space savings at system level and saving system costs.

> See here our latest LED Driver: AS1170

CMOS Image Sensor Solution with high performing Mira050  – in mono and RGB(color) versions available

As part of a bigger family of Mira imagers, the Mira050 image sensor brings new performance options to designers of industrial and consumer imaging applications, offering high quantum efficiency in a small package size. A Mira product family innovation is the ability to process mono and color (RGB) and even color combined with infrared information (RGB-IR) in the same small space to add a wealth of design flexibility – and improving face recognition and object identification.

This has the following advantages for facial recognition. Near infra-red (NIR) enhanced with high sensitivity while the global shutter enables better biometric scan quality as motion artefacts avoided, each further lowering the risk of FAR/FRR outcomes. Meanwhile, system power savings are achieved as a high quantum efficiency enables the sensor to work in low light conditions or with a “low-power” illuminator, especially for the Mira050 an automatic wake-up feature is inbuilt along with advanced power management, while shorter illumination times mean lower power consumption. Small package size leads to space savings at system level.

Indeed, based on ams OSRAM’s internal testing, by combining Mira with OSLON Black or SYNIOS P2720 IR Illumination at 920nm wavelength, high quantum efficiency is about 41.8% with the advantage of greater sensitivity for imaging.

Time of Flight (ToF9) Solution- Highly accurate direct time-of-flight presence detection

Time-of-Flight (ToF) sensors from ams OSRAM are based on proprietary SPAD (Single Photon Avalanche Photodiode) pixel design and time-to-digital converters (TDCs) which have an extremely narrow pulse width. They measure in real time the direct time-of-flight (dToF) of a 940nm VCSEL (laser) emitter’s infrared ray reflected from an object. This low-power dToF sensing technology enables host systems to accurately measure distance at very high speed. Accurate distance measurements are used in many applications e.g. presence detection, obstacle avoidance & ranging.

They contribute multiple advantages for facial recognition. The risk of FAR/FRR outcomes are lowered as they enable accurate distance measurements and provide higher accuracy. System wake up and below average power consumption aids system power saving.

> See here our dToF portfolio

Dot Projection Solution with superior dot projector acquisition of NIR image

A structured light near-infrared image can be acquired with the assistance of a dot projector. The dot pattern enhances the spatial contrast in the image to provide an excellent depth map in all lighting conditions with low contrast objects in the scene.

Face recognition relies on an accurate depth-map data of the user’s face. A facial depth map is a set of thousands of coordinates mapped in three-dimensional space describing the contours of the surface of the user’s head relative to a single point-of-view in front of the user. This depth map may be compared with a reference depth map of the user’s face to authenticate the user. A reconstructed 3D image is conveyed to the application software for further use-case-specific processing (e.g. face recognition).

Advantages for facial recognition include integrated eye safety, lowered risk of FAR/FRR outcomes due to high electro-optical efficiency and high-contrast dot-pattern and system power saving based on low power consumption. ams OSRAM provides a broad set of fully integrated dot projection solutions at different resolutions and pattern types.

> See here our latest dot projector Belago 1.1


Get more insights on or portfolio and access control and security on our webpage. 
Watch our video to learn more about how ams OSRAM supports access control and security with infrared LEDs? Or contact our team to discuss how we can help you make the most of facial authentication in your designs.