Abstract
For the recognition of the human face, we have proposed a hybrid system, which combines a optical parallel joint transform correlator using Multi-Level Zone Plate Array (MLZPA) as a Fourier transform lens with a personal computer. In this paper, we present the design procedure and the fabrication process for an improved version of a compact parallel correlator (named COPaC II: 20×24×43cm3, 6kg) by redesigning the optics and the housing to solve thermal and vibrational problems. According to the guideline of biometrics for identification, we conducted the performance evaluation of the COPaC through one-to-one correlation with 300 database of front facial images taken with same day. As a result, we obtained considerably low rate error that False Non-match Rate (FNMR) is less than 1% and False match rate (FMR) is less than 1%. As a practical application of identifications, we experiment PC-log-in for 28 days using ID-less facial images with 10 persons database. The recognition rate was obtained 92.8% and rejection rate was 96.4% after 3 times of trials. Moreover, as a preliminary experiment, we checked eight changes in facial expression such as wink, smile, close eyes, it is distrainable if arrangement of a face is a not greatly different grade. Successful recognition results using the COPaC has been demonstrated with a throughput of 7face/s and we prospect as an innovative security system.
