Beleuchtungseinrichtung an einem Mikrofilmaufnahmegerät

A microfilming apparatus wherein a single incandescent lamp illuminates successive increments of a continuously moving strip-shaped original in an image plane. The reflected light beam passes through a slit of a diaphragm and is focussed by a lens onto successive frames of a microfilm which moves continuously in the focal plane of the lens. The lamp is adjustable toward and away as well as transversely of the original in the image plane, and the width of the slit increases from its center toward both ends to compensate for the decreasing effective aperture of the lens in a direction from the optical axis toward its periphery as well as for decreasing intensity of light from the center toward the edges of the original. The lens is shielded from the lamp and is located between the two planes intermediate the microfilm and the lamp.