A contact roller system of a winding machine for thin strip material has a shaft and pivot levers arranged in a row adjacent to one another on the shaft. Subsequent to the detection of a tentative watermark, particular sections of the content are examined to form one or more extrapolated watermarks or watermark segments. The method includes detecting, by the processor, a video watch page; harvesting, by the processor, data from the video watch page; storing, by the processor, the harvested data as current page data; detecting, by the processor, a video play button operation indicating a video playing; and inferring, by the processor, the video playing correlates to a video referenced in the current page data. Since a gap between the magnetic layer and the write shield layer exerting an influence on recording characteristics is specified on the basis of the thickness of the first gap layer portion, different from the case where the gap is specified on the basis of pattern precision of the photolithography technique, the gap is controlled with high precision. Specifically, the method is a method for pattern exposure comprising the step of exposing a photosensitive material on a solid-phase substrate by irradiating it with a light as a pattern, wherein the photosensitive material is selectively exposed with beams selectively emitted from multiple vertical cavity surface emitting laser sources aligned as an array. This voltage may then be applied to the electrical circuit as the biasing voltage.