| 摘要 |
PROBLEM TO BE SOLVED: To rapidly and surely measure a liquid level for containers such as an opaque can as well as a transparent glass bottle, PET (polyethylene terephthalate) bottle, and the like. SOLUTION: A container 22 filled with a beverage is conveyed into a measuring box 20, and is fanned by a blower 26. Immediately after the container 22 is filled with the beverage, there is a significant temperature difference between liquid and gas sides. The heat distribution of the container 22 is relaxed during the movement on a conveyor 21 and the like, relaxing the temperature distribution of a gas-liquid interface. Then, by feeding the wind forcedly from outside to the container 22, the heat transfer in a surface of the container 22 is improved so as to rapidly change the surface temperature of the container 22. Accordingly, since the outside surface temperature of the container 22 to the gas-liquid interface is highlighted, an infrared radiation intensity radiated from the surface of the container 22 is photographed by an infrared camera 27 and is input into an image-processing device 28. A photographed image of the infrared camera 27 is processed by the image-processing device 28 to extract a noticeable tone portion as the gas-liquid interface. |
