| 摘要 |
PURPOSE:To get a board position correcting unit, which can correct deviation around a vertical axis without needing complicated calculation. CONSTITUTION:This correcting unit has two marks m1 and m2 for detection of positions, which are provided apart in the direction along the side edge on one side of the top of a board 1, a board supporting table 2, which has three degrees of freedom at least in X-Y-theta, an image pickup appliance 3a, which can picks up the image of the peripheral section of the mark on the topside of the board, and an image pickup position setting means, which shifts the board supporting table 2 either in X direction or in Y direction so that each mark m1 and m2 on the board may be captured with the image pickup appliance 3a. And, this board position correcting unit is composed of an angle deviation calculating means, which seeks an angle DELTAtheta made between the line connecting both marks with each other and the table shifting direction from the image data taken in at each image pickup position, and a table driving means 7, which shifts the board supporting table 2 in theta direction by the quantity required for the compensation of the angle deviation DELTAtheta. |
