IN simple terms, Hitachi’s Finger Vein technology works by using a characteristic of the human body as a unique credential. In this case it’s finger vein patterns in the human body, which vary from person to person, reducing the chance of false acceptance to virtually zero. 
Hitachi’s finger vein authentication uses images of finger vein patterns captured by penetrating the finger with near infra-red rays generated by the light emitting diodes in the reader. The light transmission technology was developed by Hitachi specifically for pattern-matching and authentication. The near-infrared light is transmitted through the finger and partially absorbed by haemoglobin in the veins.
The areas these rays are absorbed appear as dark areas in an image taken by a CCD camera located on the opposite side of the finger being scanned. Image processing is then used to construct a finger-vein pattern from the camera image. This pattern is then compressed and digitised so it can be registered as a template of a person’s biometric authentication data. All this happens in about 2 seconds.  
When a finger is presented to a reader, this process allows the reader to capture an individual’s unique finger vein pattern profile, which is then matched with the pre-registered profile to verify individual identity.
There are a bunch of advantages with biometrics, the central one being that there are no expensive card libraries to maintain and replace. At a few dollars a card, or more for higher security smart cards, the expense of replacing lost, stolen or worn out cards is considerable. 
In comparison, people rarely misplace fingers – that means less cost for the end user. Staff can register multiple fingers as back-up for authentication purposes in the unlikely event a finger does go missing. Nor are fingers readily transferable, ensuring the identity of the person accessing a door can be assured. 
Another intrinsic feature is that all the issues of duplicated codes are eliminated. The veins in your authorised user’s fingers are never going to be unwittingly duplicated by some integrator across town because the low end prox technology being used is short on numerical diversity. 
Importantly, because the surface of the skin is not being used, dryness or roughness on the surface of the skin also has no effect on the accuracy of vein pattern authentication. Registration is possible even for sweaty, oily or dirty fingers. Veins are inside the body, invisible to the eye, and not accessible for duplication. They are impossible to forge and manipulate. 
Chase says that rates for acceptance of false users or rejection of true users are among the lowest for biometric technologies, making finger vein authentication a reliable security solution. Unique vein patterns plus leading-edge technology means high accuracy rates (very low FTE, FRR and FAR). And only a small amount of data is required (400 bytes), allowing fast authentication – less than one second.  
Also handy is the fact these finger vein authentication devices are compact and can be used as embedded devices in a variety of applications. Some versions can be used in external applications and they are impervious to interference from sunlight. 
On the management side, Hitachi Finger Vein solutions can be supported by an MS-Access database host system and can be located on an Ethernet network. They feature a USB port for centralised enrolment and have data export for time, attendance and payroll. The system offers 16 time zones, as well as transaction record monitoring. Data options include RS-485 and 26-bit Weigand. 
Fact file:
Benefits of Hitachi’s system
* The FV pattern inside the finger cannot be acquired
easily without consent.
* Processing time is very fast, around 0.5 seconds to
acquire, process and validate.
* There is no link to criminality as in the case of finger-print
systems.
* A key metric is the “FTE” or “Failure to Enrol” rate,
Hitachi’s experiments show that FTE for finger-vein
system is 0%.
* FAR (false acceptance rate), the ability of a non
registered person to be authenticated, is very accurate
(0.0001%)
* FRR (false reject rate), the ability of a registered user to
not be recognised is very accurate (0.01 %).
“There are a bunch of advantages with biometrics, the central one being that there are no expensive card libraries to maintain and replace. At a few dollars a card or more, for higher security smart cards, the expense of cards is considerable”