Abstract: An automatic parts placement system is provided which is capable of placing parts in proper positions, in a short time, on a printed wiring board to realize the shortest total wiring length. Parts are each added to a parts group which is generated based on a position designated part and parts specific gravity of the part is determined. The heavier parts specific gravity of part is placed in the closer position relative to the position designated part, by applying actual specific gravity in physical phenomenon.

Abstract: A resin filled board is manufactured by forming roughened surfaces on a conductive layer in a throughhole before it is filled with a resin, forming smooth surfaces on conductive layers on the top and bottom of the board, printing the resin using a mask having an opening at a position corresponding to the throughhole to selectively fill the resin in the throughhole, and curing the resin. In this way, the surface of the conductive layer around the throughhole is smoothed, so that hardly any of the resin remains on the surfaces near the throughhole when the surfaces of the board is mechanically polished after the resin is cured. Also, the filling resin will not fall down into the throughhole.

Abstract: A route determination support device enables target point to be navigated according to ratsnest with respect to reliable outline route, thus causing wiring to be formed approximately for the route which is intended by the operator finally. The route determination support device (ratsnest display device) consists of a singularity point position calculator for calculating the singularity point representing inputted outline route, a singularity point storage unit for storing therein the singularity point calculated by the singularity point position calculator, and a target point calculator for selecting a point with the most shortest distance from among the calculated distances as the target point, while calculating distance between the position of the stored singularity point and the present position in the inputted wiring operation.