Optical scanning apparatus including an image reading section and an image printing section that share a common optical system and a method of printing and reading an image using the common optical system

摘要

An optical scanning apparatus includes a semiconductor laser, a polygonal mirror as a deflector for scanning a light beam from the laser, a photosensitive drum for forming an electrostatic latent image, a converging lens for converging the light beam from the laser onto the photosensitive drum, and a reflection mirror located between the deflector and the photosensitive drum. The reflection mirror is adapted to reflect the light beam so that a light beam reflected by the reflection mirror is used to read a source document placed at a position that is the conjugate of the position of the photosensitive drum surface with respect to the converging device. Inside the casing of the semiconductor laser are a beam splitter for light path separation and a photosensor. The apparatus has an image reader section and a laser printer section, which share a common optical system, thus providing a compact design and cost reduction and also equalizes the accuracy of image reading and printing.