| 摘要 |
<p num="1"><br/><br/><br/><br/>Temperature measurements of sheet- material such as paper can be obtained <br/>directly from an analysis of the absorption<br/>spectrum of water in the infrared region. The technique is based in part on <br/>the recognition that the central wavelength position of <br/>a selected moisture peak is dependent upon the sheet temperature; the <br/>wavelength position also has a known temperature sensitivity. <br/>Thus, once the wavelength position of this moisture peak is ascertained, the <br/>moisture temperature of the product being monitored <br/>can be calculated. The position of the moisture peak is preferably obtained <br/>from the derivative of the peak. By measuring the size of <br/>the infrared absorption and the wavelength position of the absorption peak, <br/>both the moisture content and the moisture temperature <br/>of the sheet material can be determined. The data is used for process control. <br/>Tunable laser diodes are particularly suited as the <br/>source of infrared radiation for the temperature sensors.<br/></p> |
