A Novel Optical Method of Dimension Measurement of Objects with Circular Cross-section

Common optical methods for dimension measurement apply an imaging sensor with lens. The presence of the lens in the camera (and sometimes also in the employed illuminator) increases the total dimensions of the measuring set-up. The aberrations of the lens represent a source of uncertainty. In order to simplify the measuring set-up and to reduce its overall dimensions, the proposed method applies a measuring set-up that contains no lens (it employs an imaging sensor without lens and two point light source). In this paper, the application of this method for dimension measurement of objects with circular cross-section is described. Also, several issues related to its implementation are discussed and its performance is illustrated using experimental results.