| 摘要 |
An ice detection and measurement system (100) is provided to detect the formation of ice and/or water (40) on a surface (49) and measure the thickness thereof. The ice detection and measurement system (100) includes a radiation source (10) having a wide band emission (12) whose bandwidth is in the infrared portion of the electromagnetic spectrum. The wide band infrared emission (12) is directed to a wavelength selector (20) for providing a discontinuous transmission alternating between a pair of narrow band infrared signals each centered at a different predetermined discrete wavelength. The discontinuous alternating signal (22) is applied to optical system (30) where it is divided into two beams (32 and 34) for application to respective detectors (50 and 60). Reference detector (60) includes photoconductive cell (65) for conversion of beam (34) to a reference signal for each of the discrete wavelengths transmitted by beam (34). Test detector (50) includes photoconductive cell (55) for receipt of beam (34 ) after transmission through the ice and/or moisture (40) formed on the surface (49) of infrared transparent cover (51), for establishing a test signal responsive to infrared radiation absorbed at each of the two discrete wavelengths. The test and reference signals at each of the two discrete wavelengths are compared in microcomputer (70) for detecting and measuring ice accumulation, to distinguish icing, frost and water accumulation, and to monitor the progress of the icing/de-icing process. |
