A laser beam detector 4as been constructed using a piece of pyroelectric PVDF film and the response characteristics have been measured as a function of the chopper frequency and the poling field. The frequencies corresponding to the maximum current response appeared at around 80 Hz for the films poled at 33 kV/cm and at around 30 Hz for the films poled at 333 kV/cm to 1.6 MV/cm. This is an indication that films poled under a higher poling field attain lower inhomogeneity in the spatial distribution of polarization. When the positive electrode was irradiated, the magnitude of the response signal was higher by a factor of about four than that obtained by irradiating the negative electrode. This is a good indication of the inhomogeneous distribution of polarization in the thickness direction. With a light absorbing layer coated on the irradiated electrode, the magnitude of the current response increased by a factor of about ten, while the maximum response frequency shifted below 10 Hz. This is attributed to the time delay for the heat to reach the pyroelectric polymer layer. A possibility of using the detector system in measuring the pyroelectric coefficient has been studied.

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