平面走査型マルチビームレーザー露光装置のためのマルチ周波数AOMの特性評価

抄録

Digital recording systems such as image-setters and plate-setters are required to improve the productivity and the image quality. Under these circumstances, a recording technology of multi-beam laser scanning for the drum capstan system was developed using a multi-frequency acousto-optic modulator (AOM) instead of an ultra-fast scanning device for main scan direction. The high quality AOM was developed with phased array type transducers. It achieved a high bandwidth, over 160 MHz more than that of existing systems. With a simultaneous 3-beam generation system design and with interlace scan to avoid an undesired effect by adjacent beams, the fastest recording speed of 5.0 mm⁄s, compared with 2.0-3.0 mm⁄s for existing systems, was achieved. Furthermore, some of the critical parameters of the multi-frequency AOM, such as the treatment of third order intermodulation and photosensitive media, as the design guideline, are discussed.