UNIVERSITY OF BUCHAREST
FACULTY OF PHYSICS

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2024-11-23 17:53
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Conference: Bucharest University Faculty of Physics 2002 Meeting


Section: Optics, Spectroscopy, Plasma and Lasers


Title:
OPTICAL RECONFIGURABLE NEURON BY USING THE TRANSVERSE POCKELS EFFECT


Authors:
Gabriel MOAGĂR-POLADIAN(1), Mircea BULINSKI(2)


Affiliation:
(1) Institutul Național de Cercetare-Dezvoltare pentru Microtehnologie, str. Erou Iancu Nicolae 32B, 72996, București E-mail: gabim@imt.ro

(2) Catedra de Optică, Spectroscopie, Plasmă, Laseri, Facultatea de Fizică, Universitatea din București,

E-mail: mbulinsky@lycos.com


E-mail


Keywords:


Abstract:
An optical neuron represents a device that has a certain number of inputs and an output that are optical, device that makes the weighted sum of the analog values of its inputs and compares the resulted sum with that of a threshold value. The device output is activated or not, according to the comparison result. The output could be either of the ON/OFF type or, in other cases, could be described with the help of a nonlinear function having the value of the weighted sum as its variable. The ideal case is represented by the possibility to vary the inputs’ weights at any instant of time, so as the optical neuron be able to recognize the various inputs configurations. The schematic diagram of such a device is presented in figure 1. The paper presents a new type of optical neuron, whose weights can be changed optically at any instant of time [1]. Once established, the weights are memorized for a period of few days. The structure comprises a photoelectret as the recording medium of the weights and an optical nonlinear crystal of the type of those that present the Pockels effect [2]. The device uses the transverse Pockels effect. The structure of the part used for establishing the weights values is depicted in figure 2. The paper describes the structure of the device, as well as the estimated values of its parameters. Moreover, several alternatives of the structure are described. 1. Moagăr-Poladian Gabriel – Reconfigurable Optical Neuron Based on Photoelectretic Materials, Applied Optics vol.39 no.5, p.782-787 (2000). 2. Nemeș George – Introducere în Optica Neliniară, Ed. Academiei R.S.R. (1972).