| 摘要 |
PURPOSE: To realize highly accurate analysis of components over a wide range by selecting one of a plurality of narrow range measuring means based on the measurements of a wide range measuring means. CONSTITUTION: A sample 13 is arranged on the optical axis of a projection lens 9 and the quantity of reflected light is detected 8 for each film 5A-5F which pass the near infrared ray having predetermined wavelength characteristic of absorption of moisture, for example. A control section 18 determines the content of moisture and the like based on the detected values and a prestored 19 working curve. On other words, quadratic differential absorbance is determined from each detection value and a working curve I of main wavelength 1160nm is fetched from the memory section 19 thus measuring the moisture content over a wide range. A working curve II (main wavelength is 1450nm) is selected when the measurement is lower than a predetermined value M (19%, for example) otherwise a working curve III (main wavelength is 1940nm) is selected. Since a wide range measuring means carries out measurement temporarily over a wide range followed by measurement using a plurality of preset narrow range measuring means, highly accurate measurement can be realized over a wide range of moisture content. |
