Flexible circuit board (FPC board) the substrate is copper, the circuit needs to cover the covering film, covering film material is generally polyimide, thermosetting adhesive at high temperatures to cover the film and circuit board tightly combined, pressed on the surface of the circuit board to play a protective role. fpc board production later need to process the shape, the shape of the plug connected to other electronic products. The reliability of the circuit board connection makes laser cutting more accurate.

The current FPC batch processing methods are mainly stamping method, small batch FPC and FPC prototype mainly with laser cutting. So far, many manufacturers at home and abroad have developed UV laser cutting machine to produce FPC samples, but the FPC board plug shape commonly used cutting method: cursor point identification method and text identification method, but no report plug edge identification method, the method makes the FPC board laser cutting operation more simple, cutting accuracy is also higher.

FPC laser cutting

FPC substrate is mainly divided into single-sided, double-sided and multi-layer substrate, double-sided substrate is a product developed from a single panel, single-sided substrate production process is as follows:

FPC graphic generation process

The shrinkage rate and cutting accuracy curve of FPC board indicates that when the shrinkage rate is less than 0.8‰, the cutting accuracy fluctuates in the range of 0.05 mm. With the increase of shrinkage rate, the average cutting deviation value and variance value increase. When the shrinkage rate is greater than 0.8‰, the cutting accuracy does not reach the customer requirement of 0.05 mm.

When the shrinkage rate is above 0.8‰, the average cutting deviation value is above 0.020mm and the variance is greater than 0.025mm. This indicates that when the lifting shrinkage rate exceeds 0.8‰, the cutting accuracy of FPC board cannot meet the accuracy requirement of 0.05mm profile.

The resolution of the new laser cutting machine positioning system is 3μm, clearly determine the boundary between the plug and ordinary flexible board, to provide accurate reference points for workpiece deformation correction compensation. Through the board production site verification, the new laser cutting technology can control the size of the FPC board accuracy, in line with the 0.05 mm plug cutting deviation of the application examples.