In order to make changes in wiring, or simply make a PCB copy, there's no need to have its electronic drawings. Phiplastic system allows converting of PCB image into a vectorial format suitable for importing into CAD/CAM-systems. There are two methods to restore the drawings of the PCB:
- automated approximation by polygons (Gold);
- automated approximation by lines, pads and other graphics primitives (Vector).
The first method is cheaper and almost fully automated, but the polygons are not always enough. The second method provides a complete vectorial picture of the PCB with adequate graphics primitives. The disadvantage of the second method is the higher time costs to make transformation. Nevertheless, Vector simplifies this process by the following possibilities:
- the initial vectoring is performed automatically, the user is only to correct the results;
- manual work is inversely proportional to image quality, particularly if there are photomasks, then manual operations are minimized;
- automated process of finding differences in the vector model and the original image (Inspection and Gold);
the following operations are automated:
- selection of the optimal size and position of graphic primitives;
- selection of minimally adequate set of apertures;
- elimination of the board tilt;
- use of grids;
- centering of graphics primitives;
- overlapping of layers (the number of layers is unlimited);
- all edit operations are performed on the background of a real PCB image;
- vectoring can be applied to PCB at any color-contrast stage (Color solution);
- the user is provided with powerful and ergonomic tools that are optimized for common vectoring tasks;
Sometimes PCB vectoring is done for some specific improvement. In such cases it is possible to use mixed vectoring: the bulk of the topology is quickly and automatically converted to polygons, and areas requiring improvement are vectorized in completely. Then the project is edited in a specialized CAM-system, either directly in Phiplastic, and the board is released to production. PCB improvement directly in Phiplastic is better in many practical cases, because powerful built-in editor is comparable to the known CAM-systems.
Regardless of the vectoring method, the most important quality criterion is the accuracy of the vectorial image. The same geometric calibration, which is used in Phiplastic inspection systems, allows improving accuracy and eliminating systematic scanner errors. As a result, the image accuracy is comparable to the pixel size in the scanner resolution.
See also: other stages in the PCB production, where Phiplastic systems are used.