Abstract: Positions of a plurality of reference points arranged on a reference plate (200) having a larger area than a measurement area of a measuring machine (300) are obtained as coordinate points on a standardized reference coordinate system. First, the plurality of reference points are grouped according to the measurement area of the measuring machine (300). At this time, the reference points are grouped so that one of the groups shares a predetermined number or more of the reference points with the other one of the groups (a grouping step). The reference points are measured for each of the groups (a measuring step).

Abstract: A drawing compass with a structure of L shape and a method of using the same provide improved single-hand manipulation and handling of drawing an arc or circle. The drawing compass comprises a handle rotatably mounted on one end of an arm and a pivot pin holder slidably mounted along the arm. One can make an arc or circle by simply holding the handle perpendicular to a drawing surface, placing the pivot pin at the center and making a circular motion guided by the arm of the compass. In the drawing process, the pressure applied on the marking point is directly controlled by hand. The compass is easy to use, inexpensive, and simple to manufacture.

Abstract: The invention comprises: a rest base (1) for a sample (2) to be examined, at least a first and a second optical systems (3, 4), identifying two optical paths located at a predetermined distance one from another. The at least a first and a second optical systems (3, 4) are commandable and are able to focus, with a predetermined enlargement, on two ends of the sample (2). The at least a first and a second optical systems (3, 4) are arranged and maintained on parallel planes which are also parallel to the rest base (1). The invention also comprises at least a monitoring and measuring device able to gather images sent by the at least a first and a second optical systems (3, 4). The apparatus is structured to carry out measurements of dimensions of a sample (2) while completely eliminating any influence on the measurements by the measuring system and the rest base for the sample.