Jpn J Appl Phys 2008, 47:64527.CrossRef Competing interests The authors declare that they have no competing interests. Authors’ contributions FIL carried out most of the experimental work including the material preparation and characterization and drafted the manuscript. JFY carried out the L-I-V measurements and the

life test of PQC LEDs. Both authors read and approved the final manuscript.”
“Review Ultraprecise aspheric mirrors that offer nanofocusing and high coherence are indispensable for developing third-generation synchrotron radiation sources such as Super Photon ring-8, the European Synchrotron Radiation Facility, and the Advanced Photon Source. Toward the selleck chemicals llc practical realization of these light sources, much scientific equipment and many analytical instruments that outperform conventional instrumentation are being designed. Hard X-rays at nanoscale spatial resolution are expected to find wide applications in areas such as nanotechnology, materials, biotechnology,

medical treatment, and medical manufacture. In industry, the extreme ultraviolet (wavelength: 13.5 nm) lithography used for high-accuracy aspheric mirrors is a promising technology for fabricating semiconductor devices. In addition, many digital video instruments require ultraprecise mirrors with a radius of curvature of less than 10 mm [1, 2]. A light condensing or image optical system mirror in the hard X-ray and EUV regions must perform near the diffraction limit in order to apply these light sources, which have spatial resolutions on the order of nanometers. That is, a next-generation ultraprecision mirror must meet the following requirements: a surface roughness find more of

0.1 nm peak to valley (PV) and an accuracy of form of 0.2 nm RMS. It is essential that ultraprecision machining and measurement technology progress considerably to produce such a next-generation ultraprecision mirror. Moreover, the measurement techniques require higher precision than the machining methods. Currently, these optical components are measured by interferometers and coordinate measuring machines (CMMs) [3, 4]. A CMM can measure an aspheric surface. Their reported accuracy is extremely precise, which is 10 to 100 nm. CMMs perform contact-type measurement, although they rarely damage samples because of the low measurement pressure Erastin in vivo of 15 mgf. They can measure only up to an inclination angle of 60° because the probe approaches from the upper Z-direction and scans the surface shape. Therefore, they are unsuitable for the measurement of machine elements with a high aspect ratio. The phase shift Fizeau interferometer can measure an aspheric surface with a high accuracy of 30 nm. However, it has limitations; it GDC-0449 nmr requires an external optical reference and depends on its precision, and it cannot measure a mirror with a large radius of curvature. In addition, the measured object must be approximately at least 100 mm in size.