Design method for CCD (charge coupled device) counterpoint read point on exposure film

Abstract

The invention discloses a design method for a circuit board exposure film CCD counterpoint read point. Exposure films includes a C film and an S film, a rectangular frame is arranged on the C film or the S film, and a hollow circular ring with a notch is arranged at the center of the rectangular frame; and a rectangular frame in the same size is correspondingly arranged on the S film or the C film matched with the C film or the S film, and a solid circle dot is arranged at the center of the rectangular frame. The notch number, the notch width and the inner and the outer radii of the hollow circular ring on the C film or the S film all can be arranged according to actual requirement. The method enables a CCD counterpoint circular ring membrane to be adhered onto the films more firmly, efficiently prevent the falling-off membrane from being adhered onto a plate surface of a product and polluting a developing cylinder; and meanwhile, the area of the circular ring is reduced, so that the time for an exposure machine to read CCD can be shortened, and the efficiency is improved.

Description

technical field [0001] The invention relates to the field of printed circuit board manufacturing, in particular to a method for designing a CCD alignment reading point on an exposure film in a circuit board exposure process. Background technique [0002] In the PCB manufacturing process, in order to ensure that the accuracy of the film and the product are consistent during exposure by the semi-automatic exposure machine, and to maintain the consistency of the C / S negatives, it is necessary to perform alignment correction on the C-side film, product, and S-side film to ensure that the three are within the allowable offset. Within the tolerance, the CCD lens of the exposure machine will read the CCD reading points of the three for precision adjustment. [0003] In the industry, the general design method for the CCD reading point on the C / S film is as follows: the C-side film uses a solid circle PAD, plus a blank box with a line width of 15MIL and a size of 6*6MM, and the S-sid...

AI Technical Summary

Problems solved by technology

The defects and deficiencies of this kind of alignment reading point are as follows: (1) The halo pattern dry film polymerized in the CCD reading point rushes into the developing cylinder after development, and the film is fragile and falls off and sticks to the product, resulting in poor product quality. Low rate and quality problems; (2) In addition, the peeled dry film will also pollute the developing cylinder, which increases the frequency of equipment maintenance, affects normal production, and wastes manpower and material resources; (3) The alignment accuracy is low, resulting in relative exposure accuracy lower

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