Algorithm for automatic alignment in 2D space by object transformation

Automatic alignment problem was coupled with the numerical coordinates on a machine, a vision system and wafer device. This paper proposes a method for constructing a general model for automatic alignment and formulating equations from three coordinates. The algorithm was derived under the assumption of precise positioning control and vision inspection. The idea for this algorithm originated from rigid body transformation, which is employed to describe the movement of a wafer on a dicing machine. The algorithm was based on simultaneous x, y, θ alignment. The formulated equation is in a simple matrix form, which can be connected to other mathematical equations. This equation could be used to write the current alignment models. The equation also gives a solution for direction changes among the coordinate systems. The algorithm is composed of matrices, and is very simple. An experiment was carried out on the dicing machine, and sufficient alignment performance was achieved.