| 摘要 |
PROBLEM TO BE SOLVED: To detect a gap at any position between pixel electrodes regardless of presence of absence of an inside structure by projecting reflected slit light in each inside surface of a liquid crystal cell to measure distance between project patterns. SOLUTION: A lighting system 2 converts an outgoing beam of a semiconductor laser 21 into slit light and projects it to a liquid crystal cell 1 at a predetermined angle. A detection system 3 forms reflected light on each boundary face to an image with a detection lens 31, and a CCD light-receiving device 32 receives it. In this case, slit light having penetrated a part with absence of an inside structure of the cell 1, is not divided and becomes a continuous shape, but in presence of the structure, linear slit light is divided and becomes island- like slit light. An image processing device 4 extracts a project pattern by reflected slit light on each surface by projecting a detection image of the device 32 in a longitudinal direction of a slit and measures distance between project patterns. Thereby, a gap between pixel electrodes 12, 15 can be detected even if an optical constant of an inside structure is unknown.
|
