| optical products have been inspected and tested in accordance with the " Optical Traceability System" mentioned below. The accuracy and calibration of these products are traced periodically to national standards at JQA (Japan Quality Assurance Organization), a public calibration agency, to keep the high accuracy and the good quality of the products.
Each wavelength at the transfer standard is traced to a primary standard by spatial light or light from fiber optics. Light from fiber optics is used for tracing from the primary standard to working standards. With these working standards, calibration and measurement have been performed at our development, manufacture and inspection departments. Photodiodes with wide dynamic range are built in both the primary standard and the working standards.
The wavelength of a gas laser is used as a stable standard wavelength to calibrate the wavelength of the spectrum analyzer and of the optical wavelength meter, and to check the wavelength of the semiconductor lazer and of the LED.