Optically Programmable FPGA Systems
Jose Mumbru, Gan Zhou, Arrigo Benedetti, Xin An, George Panotopoulos, Fai Mok, Demetri Psaltis, Pietro Perona

Reconfigurable processors bring a new computational paradigm where the processor modifies its structure to suit a given application, rather than having to modify the application to fit the device. The Optically Programmable Gate Array (OPGA), an enhanced version of a conventional FPGA, utilizes a holographic memory accessed by an array of VCSELs to program its logic. Combining spatial and shift multiplexing to store the configuration pages in the memory, the OPGA module is very compact and has extremely short configuration time allowing for dynamic reconfiguration. The reconfiguration capability of the OPGA can be applied to solve more efficiently problems in pattern recognition and searches in databases. (full report)

Holographic Imaging of Biological Samples
Wenhai Liu, Demetri Psaltis

We are developing an imaging system with the ability of imaging a 3D object plus the color spectrum information. It makes use of the spatial and wavelength selectivity of volume holograms, which act as multiple lens and color filters to separate the 2D slices with different color from the 3D object into various detectors. It will be a powerful tool for imaging application in cell biology, biochemistry, material research and any other 3D imaging application. (full report)

Little Piece of Cortex
George Panotopoulos, Demetri Psaltis, Pietro Perona

We introduce a model of the V1 cortex. This model is composed by an initial filter stage and two interaction stages, inspired by their biological counterparts. The model produces results matching the ones obtained by physiological experiments. (full report)

Hand Gesture Biometrics
George Panotopoulos, Demetri Psaltis

We introduce a biometric measure based on hand gestures. We use simple filters to extract features from a gesture captured in the form of still frames. We then use PCA to perform classification using these features. For small databases we obtain 100% correct classification. (full report)

Divide and Conquer Strategy for Recognition
George Panotopoulos, Demetri Psaltis

We devised a classification strategy based on the division of a single complex question to more, simpler questions. We showed that this strategy corresponds to a tree structure and can be implemented by reconfigurable computers. We demonstrated the efficiency of this strategy on the problem of classification of handwritten digits. We derived analytical expressions linking the performance of the overall classifier to the performance of its parts. (full report)