WO2014087425A2

WO2014087425A2 - An iris pattern capturing device

Info

Publication number: WO2014087425A2
Application number: PCT/IN2013/000742
Authority: WO
Inventors: Tamaal Purnendu ROY; Navin Thakorbhai PATEL; Mayur Navnitbhai PATEL
Original assignee: Biomatiques Identification Solutions Private Limited
Priority date: 2012-12-05
Filing date: 2013-12-04
Publication date: 2014-06-12
Also published as: WO2014087425A4; WO2014087425A3; AP2015008276A0

Abstract

" The Invension is in relation to the device which is capable of capturing the human iris pattern within the specifically created lighting illumination conditions so that maximum iris pattern details are captured by the imaging sensor." An iris pattern capturing and processing device (1) for unique identification comprising, - an illumination module (2) adapted to produce IR spectrum with predetermined wave length focusing on the iris of an eye, - an image capturing module (4) adapted to capture the reflected IR spectrum from iris operably connected to the illumination module (2); and - a signal processing module operably connected to said image capturing module for processing the IR signal captured by the image capturing module and extracting biometric template therefrom, - said illumination module and image capturing module being disposed within a suitable housing.

Description

4.DESCRIPTION

AN IRIS PATTERN CAPTURING DEVICE

HELD OF THE INVENTION

The present invention in general relates to an image capturing device of human eyes and in particular to an iris pattern capturing device in infrared spectrum for unique identification with faster extraction of biometric template and which does not require any major pre and post processing of image.

BACKGROUND OF THE INVENTION

The science of biometrics is merging with the field of information technology to create new methods for collecting data on a variety of other human physical and behavioral traits as well. Innovative devices and technologies capable of analyzing such traits as retinas, irises, voice patterns, facial features, and hand measurements are already being used for biometric authentication across a wide array of areas including corporate and public security systems, military surveillance, counter- terrorism initiatives, and point of sale applications.

The biometric image capturing device is very much useful for developing Unique Identification Authority of India (UIDAI) project these days. Different techniques such as Irising3000 are developed for this purpose. Irising3000, combining the infrared distance sensor with the weighted brightness algorithm, achieves the function of auto bracketing focus, which can capture a sequence of multi-focal iris images. The prototype Irising3000 reduces the need for users to meet the minimum requirements in image capture, and improves the success rate of capturing high- quality iris image.

Another model for iris image capturing device is probabilistic active contour model (PAC) which is developed by combining level set theory with variational method. In addition, region information and probability distribution are used as stop terms. Under this model, initial curve is iteratively driven towards iris boundaries. In the evolving process, eyelids, eyelashes, reflections and shadows are simultaneously detected.

Though some techniques are available in market, the underlying technology is not without its drawbacks. Iris scanners, for example, only work when targets are stationary and within very close range, making it impossible to capture iris images from moving targets at a distance. Furthermore, it is extremely challenging to collect the high quality image of the iris since almost all currently used iris recognition system's performance is greatly affected by poor-quality imaging. Apart from that, while processing iris segmentation provides available texture region, but when using portable image capture device, non-ideal iris images are often obtained.

Accordingly, there was a long felt need to develop an image capturing device for human iris pattern which utilizes accurate focus, high speed, provides accurate and fast iris segmentation and also produces high quality images. The present invention meets the above mentioned needs by providing an improved image capturing device for iris pattern of humans which is accurate, fast, devoid of the defects mentioned earlier and also provides some advantageous aspects hitherto not known in this field, as described hereinafter in this complete specification.

All throughout this specification including the claims, the words "iris", "image", "infrared spectrum", "LED", "light", "camera", and "IR" are to be interpreted in the broadest sense of the respective terms and includes ail similar items in the field known by other terms, as may be clear to persons skilled in the art. Restriction/Limitation if any, referred to in the specification, is solely by way of example and understanding the present invention.

OBJECTS OF THE INVENTION

It is the principal object of the present invention to provide an image capturing device for iris pattern of human eyes for unique identification purpose which uses infrared spectrum only to enhance iris pattern.

It is the further object of the present invention to provide an image capturing device for iris pattern of human eyes for unique identification purpose which eliminates the requirement of pre and post editing necessity.

It is another object of the present invention to provide an image capturing device for iris pattern of human eyes for unique identification purpose which is not harmful to human eyes and has no other hazardous effects.

It is yet another object of the present invention to provide an image capturing device for iris pattern of human eyes for unique identification purpose which captures the image in raw RGB format.

It is further object of the present invention to provide an image capturing device for iris pattern of human eyes for unique identification purpose which includes faster extraction of biometric template results in a high speed identification.

It is another object of the present invention to provide an image capturing device for iris pattern of human eyes for unique identification purpose which is reliable and accurate.

It is yet another object of the present invention to provide an image capturing device for iris pattern of human eyes for unique identification purpose which can be easily handheld or wall mount for best functional efficiency and cost effective.

SUMMARY OF THE INVENTION

An iris pattern capturing and processing device for unique identification comprises of an illumination module adapted to produce IR spectrum with predetermined wave length focusing on the iris of an eye, an image capturing module adapted to capture the reflected IR spectrum from iris operable connected to the illumination module and a signal processing module operable connected to said image capturing module for processing the IR signal captured by the image capturing module and extracting biometric template therefrom.

The illumination module and image capturing module are disposed within a single housing.

The illumination module comprises of a pair of spaced apart transversally projected LED modules which are capable of producing converging I spectrum with same focal length. Each such module has a plurality of IR LED array capable of generating IR ray spectrum of 700-900 nm and a red LED protector glass disposed in the light path of the generated IR spectrum for blocking any spectrum above 900 nm.

The image capturing module comprises a cold mirror located in the said reflected light path from iris and capable of blocking all reflected IR spectrum above 950 nm, an IR camera lens located at the focal point of the IR spectrum from the cold mirror for carrying the energy signal to a CMOS camera, which consists of CMOS imaging sensor and camera controller for carrying the signals to the processing unit for further processing.

The said cold mirror is adapted to remove any noise signals and the said processing unit is connected to the image capturing unit through a USB port.

The CMOS imaging sensor has suitable means for capturing light signal and has converting means for converting light signals to analog and digital signals.

The image capturing module is connected to a processing unit for extracting biometric template of iris.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

Rgure 1 shows an embodiment of the iris pattern capturing device according to the present invention.

Rgure 2 shows an illumination module of the iris pattern capturing device according to the present invention.

Rgure 3 is a LED module of the iris pattern capturing device,

Rgure 4 shows the image capturing module of the iris pattern capturing device according to the present invention.

Rgure 5 shows the image capturing process of the image capturing module according to the present invention.

Rgure 6 illustrates a flowchart of the device according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to an iris pattern capturing device for unique identification purpose which captures image in infrared spectrum between 700nm to 900nm. With the help of this particular IR spectrum illumination, exact pattern of individual's iris can be identified and specific biometric template can be produced.

Figure 1 shows an embodiment of the iris pattern capturing and processing device (1) with ail its components together. The device comprises an ambience illumination module (2), capable of producing IR spectrum of specific wavelength. The illumination module (2) consists of LED module (3) transversally projected from a back plate. An image capturing module (4) is positioned adjacent to LED module (3). The image capturing module (4) is coplanar with the object (human eye) and adapted to capture the reflected IR spectrum from the iris of the eye. The image capturing module (4) is operably connected to the ambience illumination module (2). A signal processing module (not shown) is also connected to said image capturing module (4) for processing the IR signal captured by the image capturing module and extracting biometric template there from. The illumination module (2) and image capturing module (4) are disposed within a suitable housing.

In a preferred embodiment there is a pair of LED module (3) horizontally spaced apart In this embodiment the image capturing module (4) is disposed between such pairs of LED modules. Rgure 2 illustrates an illumination module (4), which comprises a pair of on board IR LED modules (3), which generate IR illumination spectrum of required wavelength. This IR spectrum when falls on human eye (9) enhances iris pattern along with its texture. The LED module (3) comprises a plurality of IR LED array(5) capable of generating IR ray spectrum of 700-900 nm and a red LED protector glass (6) disposed in the light path of the generated IR spectrum for blocking any spectrum above 900nm. The focal point of the converging IR spectrum is positioned on the iris of an eye. The LED protector glass (6) is capable of blocking all IR spectrum above 900nm which is slightly harmful to eyes.

Rgure 3 also shows the LED module (3). The IR spectrum generated from the LED array and filtered by the protector glass is a predominantly IR spectrum and mixes with visible light spectrum before falling on human eyes , which is located on the converging focal point of the IR rays emanating from the pair of LED modules. The incident light is reflected back from the iris to the image capturing module (4) capable of capturing energy signal of the reflected IR spectrum.

Rgure 4 shows an image capturing module (4) which captures the iris image in such a format which can be viewed and processed further to extract biometric template for unique identification.

Rgure 5 shows an embodiment of image capturing module (4), where the IR camera lens (8) is placed in front of CMOS camera (7). A cold mirror (9) is located in the reflected light path from iris, which does not allow the passage of the IR spectrum above 950 nm. The cold mirror (9) is adapted to remove any noise signals and helps t focus the specified IR spectrum to the IR camera lens (8), which is located at the focal point of the reflected IR spectrum of the cold mirror.

CMOS camera (7) has a CMOS image sensor and camera controller (not shown in the figure). The imaging sensor captures light energy reflected from the object and converts the same to voltage signals using associated electronics. This voltage signals are further converted to digital signals using associated electronics. The CMOS imaging sensor has suitable means for capturing light signal and converting means for converting light signals to analog and digital signals.

An example of the standard specifications and functionality of the imaging sensor are below

a. Low power 1/7" CMOS sensor will provide excellent quality images with each pixel size of 6.0 urn X 6.0 urn with minimum picture size of 640 x 480 pixels @ 30 frames in VGA mode,

b. The noise being captured is kept at less than 50 dB.

c. Inbuilt functionality for auto white balance, auto gain control, auto band I filter, auto back-level calibration and auto exposure control together with I image quality control for color saturation, hue, gamma, sharpness and anti- blooming for best image quality even during low lighting conditions.

d. Global shutter to minimize any image distortion and best picture quality. j e. This imaging source will provides complete control over image quality, formatting and output data transfer so that comprehensive iris textures are captured for optimal human identification,

f. The image is provided in raw RGB, RGB (RGB4:2:2, RGB565/555/4 4) and YCbCr (4:2:2 format) formats for best viewing and image processing.

AH imaging sensor features are controlled via a PC through a USB connectivity so as to provide a simple yet universal connectivity to the device.

When an IR spectrum in the range 700-900 nm felfe on human eye, the visibility of iris patterns is enhanced and the reflected light energy from the iris falls on IR lens (8) after passing through the dielectric cold mirror (9). The cold mirror (9) has an optical coating made up with layering of specific materials to allow passing of IR lights of wavetength between 70pnm to 900nm and to stop all other lights of different wavelengths. The lens (8) captures the light and passes it to CMOS camera sensor (not show in the figure). The light energy will converted to digital signals using associated electronics.

Figure 6 is a block diagram of the image capturing process. USB cable is plugged to the PC and after the device being recognised, iris capturing process is initialized. The distance between camera and eye is adjusted to 8" or 20 cm approximately. If the iris image can be viewed clearly on the video frames, the frame is captured and after checking the quality of frame taken, the iris image is saved.

The image is captured in a ambience which ensures the quality so as to nullify pre and post image editing necessity. The device has unique ergonomic design so it can be easily handheld or wall mounted for best functional efficiency. The device Captures the image in raw RGB format and produces the image which complies ISO standards of 19794-6

The present invention has been described with reference to some drawings and preferred embodiments, purely for the sake of understanding and not by way of any limitation and the present invention includes all legitimate developments within the slope of what has been described herein before and claimed in the appended claims.

Claims

5. CLAIMS : I claim

1. An iris pattern capturing and processing device (1) for unique identification comprising,

- an illumination module (2) adapted to produce IR spectrum with predetermined wave length focusing on the iris of an eye ,

- an image capturing module (4) adapted to capture the reflected IR spectrum from iris operably connected to the illumination module (2); and

- a signal processing module operably connected to said image capturing module for processing the IR signal captured by the image capturing module and extracting biometric template therefrom,

- said illumination module and image capturing module being disposed within a suitable housing.

2. The device as claimed in claim 1, wherein said illumination module comprises a pair of spaced apart transversally projected LED modules (3) capable of producing converging IR spectrum with same focal length.

3. The device as claimed in claim 2, wherein each LED module (3) comprises a plurality of IR LED array (5) capable of generating IR ray spectrum of 700-900 nm and a red LED protector glass (6) disposed in the light path of the generated IR spectriim for blocking any spectrum above 900 nm .

4. The device as claimed in claim 1-3, wherein the focal point of the converging IR spectrum is located on the iris of an eye .

5. The device as claimed in any preceding claim, wherein said image capturing module (4) is disposed between the said pair of LED modules (3).

6. The device as claimed in any preceding claim, wherein the image capturing module (4) is coplanar with the IR spectrum reflected from the iris of an eye.

7. The device as claimed in claims 1 and 5, wherein the image capturing module

(4) comprises a cold mirror (9) located in the said reflected light path from iris and capable of blocking all reflected IR spectrum above 950 nrri, an IR camera tens (8) located at the focal point of the IR spectrum from the cold mirror (9) for carrying the energy signal to a CMOS camera (7), said CMOS camera consisting of CMOS imaging sensor and camera controller for carrying the signals to the processing unit for further processing.

8. The device as claimed in claim 7, wherein the said cold mirror (9) is a dielectric cold mirror.

9. The device as claimed in claim 7 and 8, wherein the said cold mirror (9) is adapted to remove any noise signals.

10. The device as claimed in any preceding claim, wherein the processing unit is connected to the image capturing unit through a USB port.

11. The device as claimed in any preceding claim, wherein the processing unit is a PC

12. An iris pattern capturing device for unique identification comprising,

- an illumination module (2) disposed having an ambience illumination module adapted to produce IR spectrum with predetermined wave length focusing on the iris of an eye ;

- an image capturing module (4) adapted to capture the reflected IR spectrum from iris operably connected to the illumination module, the image capturing device is adapted to further store and convert IR signal to suitable voltage and digital signals;