| 摘要 |
PURPOSE:To easily measure the optical absorptivity of a sample to monochromatic light with good sensitivity by projecting the monochromatic light, the intensity of which varies at desired periods, and probe light to the sample and detecting the change in the interference intensity of the reflected light or transmitted light of the probe light from the sample. CONSTITUTION:The light from a light source 9 is spectrally split by a spectroscope 10 to the monochromatic light which is then passed through an optical chopper 4 and is projected as excitation light 3 on the sample 1. The sample 1 absorbs this light at the ratio corresponding to the coefft. of absorption. While a part of the light absorbed in the sample 1 is released as photoluminescence light to the outside of the sample, the rest is converted to the heat in the sample. The sample 1 is expanded by this heat and the intensity of the interference light 6 of the reflected light of the probe light 5 from the front and rear faces of the sample 1 is changed. Since the excitation light 3 is modulated by the chopper 4, the sample 1 repeats expansion and contraction in synchronization with the modulating frequencies. The intensity of the interference light 6 varies as well in synchronization with the modulation frequencies and, therefore, the absorption coefft. of the sample is determined from the amplitude of this interference light 6. |
