Abstract: A method for making an image line (10) with a laser beam, according to whichthe laser beam is created by a laser (1)the intensity of the laser beam is modulated by an external modulator or by said laser (1)said modulated laser beam is fed into a coding element (2,3), by means of which at least one of the properties of the laser beam is transformed, e.g. amplitude, phase or direction, using an electrical control signalthe coded laser beam is fed into the hologram (9), by means of which the laser beam is transformed into focused image spots (20 . . . 24a,b,c)from said image spots (20 . . . 24a,b,c) an image line (10) is formed on the image plane andsaid laser beam is guided and transformed by optical elements.

Abstract: The invention concerns a method to control accurately a light beam used for writing text or pictures in phototype-setting and similar applications. Rulings or gratings consisting of slits or lines are attached to the image surface frame and in some realizations to the optics frame. The light beam and in some realizations one or several reference beams, separated from the write beam, are made to fall on the rulings or gratings. The signal observed by photodetectors from the rulings give information on the relative positions of the light beams, the rulings and the image plane. This information is translated by electronic circuits into information of the position of the write beam on the image surface. By means of feedback mechanisms this information allows one to control the position of the write beam accurately.