For the polishing machine, people can be said to be qui […]
For the polishing machine, people can be said to be quite familiar with, then how to measure the flatness error of the polishing object, how to measure it, the following China Polishing Machine suppliers will share it.
The measurement method of flatness error can be divided into direct measurement method and the indirect measurement method. The direct measurement method is to directly compare the measured actual surface with the ideal surface. The linear distance between the measured surface and the ideal surface is the flatness error value of the measured surface. The indirect measurement method is to measure the relative measurement basis of several points on the actual surface. The height difference or tilt angle is used as the raw data and then converted to the flatness error expressed as a line value.
In nature, a small piece of liquid surface can be used as a natural plane of the level, but to obtain such a plane must overcome the undulation caused by airflow and vibration and the edge effect caused by surface tension; a stricter working environment.
A common method of flatness measurement is shown in FIG. Figure a is measured by the indicator, the parts to be tested are supported on the flat plate, and the three points farthest from the measured plane are adjusted to be equal to the height of the measuring plate. Measure the surface to be measured at a certain point. The difference between the maximum and minimum readings on the indicator is the flatness error value of the plane.
The flatness error is measured by a flat crystal. The flat crystal is closely attached to the plane to be measured, and the interference fringes generated are calculated to obtain the flatness error value. This method is suitable for high precision facets.
The level meter measures the flatness error. The level passes through the bridge. Place it on the plane to be measured and measure it point by point with a level by a level. Calculated the flatness error value.
Using a self-collimator and a mirror to measure as shown in Figured, the self-collimator is fixed at a certain position outside the plane. The mirror is placed on the plane to be measured. Adjust the self-collimator so that it is parallel to the surface to be measured and measure point by point according to a certain point and direction. After calculation, the flatness error value is obtained.