Research Of The System To Soft Measurement Of High-temperature Field Based On Ccd Image Sensor

The contactless soft measurement technology of high-temperature field based on CCD (charge-coupled device) image sensor, which combines the CCD technology, digital image processing and traditional radiation thermometry, has the characteristic of measuring temperature field rapidly and accurately, and enhances the level of measurement technology significantly. Therefore, it becomes the research hot point in the high-temperature measurement field recently. A new method for high-temperature field soft measurement based on CCD image sensor is proposed from the research of history and present situation for CCD thermometry, theoretical analysis, and a mass of experiments. The main results for the research are as follows:1. In this paper, all the essential instruments structure of the contactless temperature measurement system are studied, the method to select equipment adapted to temperature measurement is proposed and a contactless temperature measurement system based on color CCD image sensor is constructed.2. As the shooting of the high-temperature melt surface covered with a lot of smoke in Industrial Field, it is difficult to effectively segment. A combinated recognition method of target image is proposed, which firstly applies dichroic segmentation algorithm to remove various noise, and then uses the improved Otsu segmentation algorithm for high temperature target image. Finally, the morphology method in mathematics is applied to process the segmented image and remove the dissociations and narrow holes, which will smooth the image's edge. The experimental results show that the method can recognize high temperature radiator with high accuracy and practicability.3. CCD measurement range can be expanded by adjusting the combination of aperture and shutter automatically. The experimental results prove the practicability of the method.4. Theoretical analysis and experimental research indicate that using neutral filter can expand CCD measuring range with limited effect. Furthermore, the lower limit of temperature measurement will rise with the reducing of filter transmittance.5. Based on the research of calibration experiment principle of temperature measurement system, the calibration experiments are planed. Then the calibration experiment system and high-temperature field measurement system based on CCD are built. Finally the measurement system is calibrated.6. On the basis of above works, a high-temperature field soft measurement system based on CCD image sensor is used to measure the temperature of high-temperature metal melt in industrial locale. The experimental results indicate the system can measure temperature with high accuracy, practicability and promotion values.