A METHOD OF SUBTITLING MOTION PICTURE FILMS

摘要

ABSTRACT OF THE DISCLOSUREA method of subtitling motion picture films in whichgraphics elements, characters, or texts are added to a motionpicture film by means of a laser beam travelling over the zoneto be marked of the film, comprises the following two steps:a first step, in which a laser etching operation is performedby applying a laser beam whose speed of displacement over thefilm lies in the range about 1 cm/s to about 200 cm/s, with itspower on the film lying in the range about 100 milliwatts toabout 20 watts, and with the ratio V/P of the displacementspeed expressed in cm/s divided by the power on the filmexpressed in watts lying in the range 10 to 30 so as to be highenough for the laser beam to achieve complete transformation ofthe emulsion in the etched zones by causing the emulsion to beheated, softened, and dislocated, but without totallyeliminating the transformed emulsion; and a second step, inwhich the etched film is subjected to cleaning treatment forcleaning the etched zones so that the particles of emulsionthat have been heated and dislocated by the laser beam areeliminated from those zones of the film that have previouslybeen marked by the low power laser beam, thereby causingtransparent subtitles to appear.