The measurement of motionless water surface shape using laser scanning and optical project methods

In order to study the possibility of machinery of small size using surface tension of liquid, the water surface shape should be measured precisely. When the object on water is relatively light, then the deformation of water surface would be somewhat small. In this case, a laser scanning method is proposed. By this method, we can get the shape of water surface through the measuring of slope of water surface. In order to get the shape of water surface, and also escape from precise calibration of measurement system, we proposed an iterative algorithm through which we can compute the shape of water surface precisely. If the object on water is relatively heavy, which can produce somewhat large deformation of water surface. In this case, we proposed to measure the shape of water surface by optical projection. Using an ordinary lamp as the background light, a numerical camera to collect the image of water surface from the side of transparent water vessel. Through image processing, the shape of water surface can be gotten. Comparing with theoretical calculation, the experiment results exhibit that the two methods all coincide with the theoretical one very well.