We developed a line standards measurement system using an optical microscope and measured two kinds of line standards. It consists of three main parts: an optical microscope module including a CCD camera, a stage system with a linear encoder, and a measurement program for a microscopic image processing. The magnification of microscope part was calibrated using onedimensional gratings and the angular motion of stage was measured to estimate the Abbe error. The threshold level in linewidth measurement was determined by comparing with certified values of a linewidth reference specimen, and its validity was proved through the measurement of another linewidth specimen. The expanded uncertainty (k=2) was about 100 ㎚ in the measurements of 1 ㎛~10 ㎛ linewidth. In the comparison results of line spacing measurement, two kinds of values were coincide within the expanded uncertainty, which were obtained by the one-dimensional measuring machine in KRISS and the line standards measurement system. The expanded uncertainty (k=2) in the line spacing measurement was estimated as √(0.098 ㎛)² + (1.8×10?⁴×L). Therefore, it will be applied effectively to the calibration of line standards, such as linewidth and line spacing, with the expanded uncertainty of several hundreds nanometer.
