| 摘要 |
PCT No. PCT/DE94/00765 Sec. 371 Date Nov. 13, 1995 Sec. 102(e) Date Nov. 13, 1995 PCT Filed Jun. 30, 1994 PCT Pub. No. WO95/03531 PCT Pub. Date Feb. 2, 1995An acoustic microscope allowing both the topography and the elasticity of a sample to be measured at the same time. To this end the displacement of a cantilever with a tip is measured by the deflection of a laser beam. In order to measure the topography, the average deviation of the tip is held constant by a regulation circuit. The regulation circuit consists of a split-photodiode which supplies a neutral signal to the output of a normalizing amplifier which delivers a neutral value. Deviations from this neutral signal are compensated by a z-electrode of a piezocrystal. The elastic properties of the sample are measured by coupling ultrasound into the sample by means of a transducer and the high-frequency displacements of the cantilever with the tip are detected by a second detection device that consists of knife-edge detector and a fast photodiode. The detection device may also consist of a heterodyne time-of-flight interferometer or a capacitive detection scheme. |
