Yutaka Kuriyama

Development of Ultra Precision Long end Standard Installing Vacuumed Optical Path Laser Interferometer

Reducing uncertainty of the standard is one of the most effective factors to realize the high-accuracy length measurement. However, scales (e.g. Gage Blocks, Standard Scales) have uncertainty of 10 −6 ∼10 −7 at most. Therefore, to supply practical length standard that has uncertainty of 10 −8 or less, we have developed an ultra precision long end standard installing a vacuumed optical path laser interferometer. It has been confirmed that the length change owing to the installation posture change of the standard is able to be kept within 1nm(p-p) in the total length of 500mm.

Evaluation of acceleration and deceleration profile of velocity and a new design method using Gaussian distribution curve

In this paper, we propose a new evaluation index of smoothness, and an originally developed design method of the profile using the Gaussian distribution curve (GD curve). Moreover, the smoothness of GD curve is compared with the conventional quadratic curve and the cycloid curve by using the frequency analysis. These profiles of velocity are applied to the fine measuring machine, and the validity of the evaluation index is confirmed.

Development of a Calibration Equipment Using Laser Interferometer Combining a Variable Length Vacuum Cell

According to a requirement concerning measuring instruments that have to be certified their traceability, a new calibration equipment for displacement sensors has been developed. In order to estimate measurement uncertainties correctly, it is effective to make the traceability chain shorten. Thus, a 633nm commercial stabilized He-Ne laser wavelength with relative measurement uncertainty of 10 −9 order and a variable length vacuum cell for laser pass are applied for the laser interferometer system in this equipment. Moreover, in order to keep its mirror’s posture constant for the laser beam, a friction-drive unit and air bearing guide are employed. The expanded uncertainty (k=2) of this equipment is estimated to be 2.80nm, in the stroke of 50mm and the resolution of 0.08nm.