Ellipsoidal line cut system and method for hearing aid shell design

摘要

To improve the appearance of a custom hearing aid, the shell is trimmed using an ellipsoidal line cut to eliminate portions extending beyond the boundaries defined by a three dimensional ear model. The result is said to be a shell with a less visible cut than that produced from conventional methods. Line cut, contour, merger, and elimination algorithms are used for defining a line cut plane that is not parallel to a bottom cut plane, together with a projected contour on the bottom cut plane, a line cut surface between the line cut plane contour and projected contour, and the parts to be eliminated.—DAP