Silver nanoparticles were successfully synthesized by 6 MeV electron irradiation process in aqueous solution containing poly(vinyl alcohol) to produce a composite. The resulting composite characterized by UV-Vis spectroscopy, X-Ray diffraction and transmission electron microscopy reveals nucleation and growth of silver nanoparticles with an average diameter of 12 nm and having surface plasmon resonance peak at 395 nm. The nano-silver/poly(vinyl alcohol) composite was then coated on p-type conducting silicon by drop casting method and the ability of the resulting device as a optical sensor was investigated. The novelty of prepared sensor device is its reversible and rapid response, which is proportional to incident light intensity within the range of 20-80 mW/cm(2) over a wide optical wavelength region. The Schottky junction showed good rectification and photo-response characteristics within the applied voltage. The photo-current developed was found to increase with increasing incident light intensity. The novelty of the device is its photo-response, which was found to be in good agreement with the transport of optically (surface plasmon) generated charge carriers though charge transfer complexes formed in composite.