Abstract: A photovoltaic device, wherein a non-crystalline semiconductor layer of one conductivity type formed on a single crystal or a polycrystalline semiconductor substrate of the opposite conductivity type is annealed thereby to change the non-crystalline semiconductor to a polycrystalline semiconductor, with a pn junction plane formed therebetween. The depth of the junction plane is 500 .ANG. or less from the light incident surface of the polycrystallized semiconductor. Moreover, the light incidence surface can be made uneven by increasing the growth rate of the non-crystalline semiconductor.

Abstract: A photovoltaic device has a crystalline layer of a first conductivity type formed of crystalline silicon semiconductor material, an amorphous layer of an opposite conductivity type formed of amorphous silicon semiconductor material, and a microcrystalline layer formed of substantially intrinsic microcrystalline silicon semiconductor material provided between the crystalline layer and the amorphous layer.

Abstract: An electrostatic recording apparatus includes a photosensitive drum which is charged at +700 V by a first charger. Intensity of the light emitted from an LED array that is downstream from the first charger is adjusted such that a light image having strong intensity and/or a light image having weak intensity can be irradiated to the photosensitive drum. A surface voltage of a portion where the light image having weak intensity is irradiated becomes +400 V. A surface voltage of a portion where the light image having strong intensity is irradiated becomes +100 V. The photosensitive drum is charged at -400 V in the reverse polarity opposite to that of the first charger by a second charger which is arranged downstream from the LED array. As a result, electrostatic latent images of three gradations having voltages of +300 V, 0 V and -300 V respectively are formed on the photosensitive drum.

Abstract: A recording head comprises a magnetically permeable substrate, a superconducting film formed on one side of said substrate, a means for producing a uniform magnetic field sustantially perpendicular to a surface of the superconducting film, and a means for locally destroying the superconductivity of the superconducting film so as to produce a pattern of normal conducting portions in the area of the superconducting film where the magnetic field is applied. A recording device comprises a recording head for producing a pattern of a magnetic field on a recording medium, a toner supply unit arranged in face-to-face relationship with the recording head at a spaced short distance from the head to form a visible pattern of magnetic toners on the recording medium, and a fixing unit for fixing the magnetic toners on the recording medium to complete a record.

Abstract: The present invention relates to a photovoltaic device using hydrogenated amorphous silicon as a photoactive layer, wherein the ratio of the number of silicon atoms bonded to hydrogen atoms to the total number of silicon atoms (expressed as a percentage) is 1% or less and the density of dangling bonds is 1.times.10.sup.17 cm.sup.-3 or less. Accordingly, the device of the present invention has the following advantages: the cost can be reduced by forming a thinner layer, the area of the photo-active layer can be increased, the efficiency of photo-electric conversion is improved, and photo-deterioration is reduced.