A Research of Liquid Level Measurement Based on Linear CCD

A new method of liquid level measurement based on linear charge coupled device is presented in this paper. It is proposed that the liquid level images are directly projected onto the linear charge coupled device without any optical lens by using light emitting diode. The method is studied experimentally with a measuring device, which is designed for the proposed method on the basis of field programmable gate array and a host computer. Field programmable gate array is used as the control core to generate timing pulses and to control the main chips of the hardware circuit. The host computer is used to process the image data. The proposed method is on the basis of the contact measurement and has the advantages of high precision, high reliability, good real-time performance and so on. The experimental results show that the changes of the temperature have little effect on the measuring accuracy. In addition, the measuring device works normally even in some rigorous environments, such as in corrosive liquid and in sloshing liquid. Therefore, the proposed method has great potentialities, especially in small range and high precision situation.