| 摘要 |
PURPOSE:To ensure the positioning with high accuracy by supplying the transmitted light from the vertical direction to a detecting optical part provided between two transmitting plates. CONSTITUTION:The beams of light irradiating 14 and 15 transmit through glass plates 1 and 2 respectively and enter a detecting optical part 16. A position detecting circuit 8 drives the plate 2 supported by tables 10a and 10b via a table control circuit 9 so as to obtain the coincidence between the images supplied via an image detector 17. Then the positioning is repeated between patterns 3 and 4 until the shift degree between them is less than the allowable value. Then up-down moving blocks 11a and 11b are moved down by a motor 13 after an optical part 16 for detection is saved by a saving mechanism 18 to approximate to the glass plates 1 and 2 by a prescribed minute distance. These plates 1 and 2 are fixed by a clamping tool. In such a way, the positioning is possible with high accuracy between patterns 3 and 4. |
