| 摘要 |
PURPOSE:To decide whether or not a printed board is normal through image processing by applying a pattern with a driving signal for liquid crystal through a contactor arranged in contact with the entire surface of the board and displaying the pattern whose potential varies on a liquid crystal display device. CONSTITUTION:A liquid crystal driving circuit 3 outputs the driving signal to an optical section on the circuit board 4 by a control circuit 10 to apply a minus signal to the common pattern of the liquid crystal display device 2 and a plus signal to the circuit board 4. The plus signal is applied to the printed board 1 to be tested through the conductor of the contactor 5 connected to the section where the liquid crystal is to be driven, and the state of the potential is applied to the drive pattern of the liquid crystal display device 2, so that the shape of the conductive pattern of the board held at the same potential with the plus signal is displayed on the liquid crystal display device 2 by the potential difference from the minus signal applied to the common pattern. The image of the conductive pattern displayed on the liquid crystal display device 2 is photographed by a camera 6 and image information on it is inputted to an electronic circuit 7 to extract its features. Then, the data is compared with reference data in a storage circuit 9 by the control circuit 10. |
