Smart Sensors BMT-20

Cost Effective and Easy-to-use Iris Recognition for Biometric Enrollment

 

The BMT-20 is a binoculars-type iris biometrics imaging device that simultaneously and quickly captures highest quality iris biometric images. Easy to use, the system can be reliably positioned by the subject with minimal instructions, or by an operator with the aid of positioning feedback LEDs on the top of the imager s housing.

     

The patent-pending optical design of the BMT-20 features expanded depth of field and a very large tolerance for inter- pupillary distance, which provide superior tolerance for the positioning of all subjects eyes. The BMT-20 is ideal for enrollment programs of all sizes, including those involving very young children.

Designed with the latest in optical and system control technology by one of the leaders in the industry, the BMT-20 is physically robust, highly reliable and durable. Meeting the elevated IP64 intrusion protection standard, this system is sealed against dust and other airborne particles to provide extended life in harsh environmental conditions.

Key Features

State-of-the-art optical design

The optical design includes utilizing highest quality optics and long internal optical path, which allows the BMT-20 to exceed industry standards for image quality as specified by ISO in the 19794-6 document. The standard is 4.0 lp/mm at 60% contrast ratio.

Single sensor design

The proprietary and patented single sensor design interleaves left and right iris images for simultaneous capture. By utilizing only a single sensor, power consumption through the USB connection is minimized. This allows for optimized NIR illumination, resulting in the shortest exposure times possible, thereby minimizing any potential for motion blurring.

Long internal optical path

The optical design is folded within the BMT-20 system, providing the longest optical path of any binoculars-type iris recognition imager. At 365 mm ( +/- 15 mm), the long optical path provides much greater depth of field while minimizing optical distortions.

Dedicated, on-board image processor supports very high speed, simultaneous capture of subjects irises

In real-time coordination with the host PC software, the on-board image processor facilitates very high speed image capture, resulting in the fastest and most robust capture of both of the subject s irises at the same time. Typically, both irises are captured within one (1.0) second from the time that the subject places the system on his/her forehead.

Extended depth of field

The BMT-20 is capable of imaging over a depth of 30 mm, making the system highly tolerant of a) subject positioning in the  Z  dimension and b) how deep the subject s eyes are relative to his / her forehead. The BMT-20 therefore offers highly robust iris imaging across the widest range of people, including small children.

Wide inter-pupillary distance tolerance

The BMT-20 can capture iris image pairs from subjects with inter- pupillary distances as small as 4.0 cm, which is the minimum distance for a child of 5 years old. This makes the BMT-20 ideal for enrollment of all subjects within all national identity programs.

All solid-state design-no moving parts

The superior optical design of the BMT-20 provides the widest inter- pupillary distance and depth of field without needing any moving components. Reliability and durability are optimized with an all solid- sate design.

Meets IP64-6 specifications for particulate intrusion prevention

Meeting this very high standard means that the BMT-20 is highly resistant to contamination by very small airborne particles such as dust and dirt, such as would be commonly found in harsh non-conditioned enrollment environments. Stringently tested against this standard, this feature will provide extended life and high reliability. Other systems only meet the lesser IP54 specification.

Internal white LED

Internal, white light emitting diodes (LEDs) are turned on just prior to imaging to constrict the subject s pupil for iris biometric image capture, providing ideally sized pupils for optimal iris biometric identification and authentication.

In dark rooms, the pupils of most subjects will dilate, shrinking the amount of iris area, which diminishes the effectiveness of the iris biometric image. By making the iris area larger, the iris biometric images are optimized.

 

Near-real time off-axis gaze detection

Detection of subject gaze angle (i.e. whether the subject is looking directly ahead at the imager), which is the correct position of the eyes for optimal iris biometrics. If the subject is looking away, the system will automatically wait to capture a valid iris biometric image until the subject does look straight ahead.

Motion detection

System calculates eye motion relative to the system, and waits until subject meets motion threshold (which is adjustable) in order to assure there is no adverse motion blurring of images.

Foldable side visors and forehead positioning rest

Side visors and the forehead positioning aid on the BMT-20 combine to block bright light, such as sunlight, from entering the optical path of the system during imaging. In this way, the BMT-20 can be utilized outdoors and still deliver ideal iris biometrics imaging.

External color LED positioning indicators

The BMT-20 can be operated in two modes: first by the subject himself after being giving short and easy to understand instructions. The system can also be operated by a trained operator, who will position the device based on external color LED s to center the system over the subject s eyes.

  • Red : Device is too high
  • Blue : Device is too low
  • Green : Device position is OK
Position sensor

A position sensor detects if the system is upside down, preventing capture of images that can be reversed, left and right. This assures that all iris biometric samples are exactly as intended.

High temperature range

The tested and certified operating temperature range of the BMT- 20 is a full 0 to 50 degrees Celsius, making the system fully useable in non-conditioned environments in the hottest of summer days.

Powered by USB 2.0 cable

The BMT-20 is fully powered by the USB 2.0 connection (maximum 500 mA at 5.0 V), which means that it operates without an independent power supply.

Technical Specifications

Dimensions 219x161x58mm (8.6x6.3x2.3inches)
Weight 680 g (1.5 lbs)
MTF / spatial resolution Exceeds 4.0 lp/mm @ > 60% contrast
Pixel resolution 18.4 to 20 pixels/mm
Iris image pixel resolution 640 x 480 pixels
Image output Meets ISO 19794-6
Capture distance (to forehead) 0 to 10 mm (0.0 to 0.4 inches)
Optical path distance 350 to 380 mm
Depth of field 30 mm (1.2 inches)
Inter-pupillary distance covered 40 to 90mm (1.6 to 3.5 inches)
Time of capture Around 1 second, typical, from time of head placement
IR illumination for iris imaging Dual LED: wavelengths of 850 nm nominal (~ 60%); and 750 nm nominal (~ 40%)
Internal LED for pupil contraction Broadband visible (white)
External LED indications for operator assisted positioning

Red: Device position is too high

Blue: Device position is too low

Green: Device position is OK

White: Image capture in progress

Operating temperature range 0 to 50 C
Humidity 10 to 90% RH, non-condensing
Eye safety standard IEC 62471, IEC 60825-1
Durability IP64 intrusion prevention standard
Interface USB 2.0 High Speed
Power USB 2.0 (500 mA at 5V), No additional power required
PC hardware and OS requirements

Intel  Atom  or above processor

Windows XP 32 bit or above

Linux OS version of SDK and drivers in progress

Other certifications CE , FCC, USB-IF, India STQC, RoHS, WHQL