| 摘要 |
PURPOSE:To extract the internal data on the surface of a sample and the vicinity of the surface at a high speed in two dimensions without the effects of the distribution of the reflectivity and the distribution of the irregularities on the surface of a sample. CONSTITUTION:The individual measuring points along the straight line on the surface of a sample 47 are excited at the same time with a stripe beam 101. Optical interference is utilized in the detection of the photo-acoustic signal generated at each measuring point. The interference lights are detected with a sensor 82 in parallel at the same time. The digital processing is performed at a high speed in an extracting device 401. Thus, the photoacoustic signal at each measuring point is extracted at the high speed. Then, the two-dimensional image is displayed with a computer 403 in real time, and the internal defect of the sample 47 can be inspected. |
