Abstract This application describes a photosensitive device which comprises a thin sheet of a polymeric compound having an electrode directly on each face, the relationship of the work functions of the polymer and of the material of at least one of the electrodes being such that there is charge transfer across the interface when the device is illuminated. The polymeric compound is one in which there is a high degree of electronic orbital overlap between hydrogen atoms in adjacent polymer chains, or is a polymeric vinyl compound which carries groups on carbon atoms of the polymer chain which have a high electronegativity. Typically useful polymers are polyvinyl fluoride, polyvinyl acetate, polyvinyl alcohol, nylons, polyurethanes and polyacrylamides and copolymers of vinylidene fluoride and hexafluoropropene. On application of 100 V between the electrodes in the dark and under conditions of illumination of 1000 lux, a difference in dark and photocurrents of at least a factor of 10 may be obtained.
A photosensitive device according to claim 1 wherein the polymeric compound, electrode material and thickness of layer are selected so that a measurable difference between dark and photo-currents is obtained on application of an external voltage.
Claim 2
Dependent Claim
54 words
A photosensitive device according to claim 2 wherein the polymeric compound, electrode material and thickness of layer are such that on application of 100 V between the electrodes in the dark and under conditions of illumination of 1,000 lux, a difference in dark and photocurrents of at least a factor of 10 is obtained.
Claim 3
Dependent Claim
59 words
A photosensitive device according to claim 1 which will pass photocurrent when illuminated by radiation of wavelength longer than the wavelength of the absorption edge of the electrode material and of the polymer, said polymer being selected from the group consisting of polyvinyl fluoride, polyvinyl acetate, polyvinyl alcohol, nylons, polyurethanes and polyacrylamides and the electrode material comprising polyethylene oxide.
Claim 4
Dependent Claim
33 words
A photosensitive device according to claim 1 wherein the polymeric compound, electrode material and layer thickness are such that on illumination, said device will pass a photocurrent of at least 10 7 A.
Claim 5
Dependent Claim
18 words
A photosensitive device according to claim 1 wherein the polymer is a copolymer of vinylidene fluoride and hexafluoropropene.