High Speed Holographic Optical Correlator for Face Recognition

Owing to the Japanese government plan, U-Japan, which promised to bring about the socalled ‘ubiquitous society’ by 2010, the use of Internet has dramatically increased and accordingly, development of the system through IT networks is thriving. The term ‘ubiquitous society’ became a buzzword, signifying easy access to content on the internet for anybody, anywhere and at any time. Face recognition has become the key technique, as a ‘face’ carries valuable information, captured for security purposes, without physical contact. They can function as identity information for purposes such as login for bank accounts, access to buildings, anti-theft or crime detection systems using CCTV cameras. Furthermore, within the domain of entertainment, face recognition techniques are applied to search for celebrities who look alike. Against this backdrop, a high performance face recognition system is sought after. Face recognition has been used in a wide range of security systems, such as monitoring credit card users, identifying individuals with surveillance cameras and monitoring passengers at immigration control. Face recognition has been studied since the 1970s, with extensive research into and development of digital processing (Kaneko & Hasegawa, 1999; Kanade, 1971 ; Sirovich & Kirby, 1991 ; Savvides, M. et al. 2004). Yet there are still many technical challenges to overcome; for instance, the number of images that can be stored is limited in currently available systems, and the recognition rate needs to be improved to take account of photographic images taken at different angles and in varying conditions. In contrast to digital recognition, optical analog operations process two-dimensional images instantaneously and in parallel, using a lens-based Fourier transform function. In the 1960s, two main types of correlator came into existence; the Vanderlugt Correlator and the Joint Transform Correlator (JTC) (Goodman & Moeller, 2004). Some correlators were a combination of the two (Thapliya & Kamiya, 2000; Kodate Inaba Watanabe & Kamiya, 2002 ; Kobayashi & Toyoda, 1999 ; Carrott Mallaley Dydyk & Mills, 1998). The authors previously proposed and produced the FARCO (Fast Face Recognition Optical Correlator), which was based on the Vanderlugt Correlator((a) Watanabe & Kodate 2005; (b)Watanabe & Kodate, 2005). Combined with high-speed display devices, four-channel processing was able to achieve operational speeds of up to 4000 faces/s. Running trial experiments on a 1-to-N identification basis using the optical parallel correlator, we succeeded in acquiring low error rates of 1 % False Acceptance Rate (FAR) and 2.3 % False Rejection Rate (FRR)( Savvides et O pe n A cc es s D at ab as e w w w .in te ch w eb .o rg