process and device for checking the debt claims

摘要

1292375 Photo-electric security authentication SCHEIDT & BACHMANN GmbH 6 March 1970 [8 March 1969] 10864/70 Heading G1A In an arrangement for authenticating a security bearing printed lines or rows of dots, the security is moved at a constant speed between a light source and a grid in an arrangement, light source - grid - photo-cell. The photo-cell may comprise a photo-diode including in series a resonant circuit and the resulting output may be applied to a transistor amplifier. The line characteristics of the grid preferably conform with the printed lines.