Patent ID: 7122786

Claim:
A controlling method of an optical switching device in which for said optical switching device including a first mirror array and a second mirror array, each arranged in a plane with a plurality of tilt-mirrors each having a controllable reflecting surface, and sequentially reflecting optical signals input thereto by said first mirror array and said second mirror array to output from specific positions, said controlling method controlling angles of the reflecting surfaces of the respective tilt-mirrors of said first and second mirror arrays, said controlling method comprising: detecting an arriving position and an arriving direction of an optical signal reflected by said second mirror array; and judging, based on said detecting, the angles of the reflecting surfaces of the tilt-mirrors which reflected said optical signals of said first mirror array and said second mirror array, and correction controlling the angles of the reflecting surfaces of said tilt-mirrors so that said angles approach previously set target values, respectively, wherein said detecting comprises branching a part of the optical signal reflected by said second mirror array and receiving a branched light at a light receiving surface thereof having a two-dimensional area to generate position information, and said judging comprises comparing the generated position information with initial position information previously set corresponding to the target values of angles of reflecting surfaces of said respective tilt-mirrors, to thereby detect an error in the arriving position of said optical signal, calculating angle deviations of the reflecting surfaces of said respective tilt-mirrors based on the detected error in the arriving position, to thereby compute correction angles of the reflecting surfaces of said respective tilt-mirrors, wherein said calculating comprises calculating angle deviations of the reflecting surfaces of the respective tilt-mirrors to thereby compute correction angles of the reflecting surfaces of the respective tilt-mirrors by using a first angle change amount when forcibly changing only the angle of the reflecting surface of the first mirror array, and a second angle change amount when forcibly changing only the angle of the reflecting surface of said second mirror array, such that an error detected by said comparing becomes substantially zero, and controlling the angles of the reflecting surfaces of said respective tilt-mirrors, in accordance with the computed correction angles.