Method of Photomask and Blank Alignment for Direct Exposure of PCB Based on a Liquid Crystal Matrix

A method of optical alignment of photomask and blank for installing direct exposure of PCB on a liquid crystal matrix to form a desired topology on the photosensitive material is presented. In particular, the processes of calibrating the video camera position relative to the working field of the installation and positioning the image with the transferred topology relative to the workpiece position are considered. Implementation algorithms are compiled for each process and experimental testing is performed to confirm their operability. Statistical analysis shows an error in alignment the photomask topology with the blank of ± 300 microns. The developed algorithms and corresponding software implementations can be used as a methodological and programmatic basis for a study of methods for evaluating and compensating for PCB deformation during its manufacture.