An on-machine measuring system based on the use of an LTP optical head was developed to accurately measure the slope error and profile error of long parts just after machining. Cylindrical surfaces can be measured completely by steering the beam up the sides of the cylinder with a rotatable mirror. To increase the reliability to measure the cylindrical surfaces, the optical system of the LTP head was improved. A personal computer collects all the data and controls the machine positioning and the beam steering mirror automatically.
We propose a method to make advanced thin-foil substrates for an X-ray telescope by press forming. Walter Type-I optics, which reflect X-rays twice with their confocal paraboloidal and hyperboloidal reflectors, have commonly been used in X-ray astronomy.
However, it is difficult to make substrates for a large X-ray telescope with a high imaging quality. By forming two reflectors from one thin substrate, the accuracy of the angle between two reflectors is determined by the accuracy of a mandrel or a stamping die.
We made a stamping die using a precision processing method at RIKEN. After several improvements of our pressing method, we have obtained the substrates with a figure error < 15 um, which corresponds to an angular resolution of about 2' at the focal plane, although a small waviness was found in the mirror surface. We also propose a new holding method of the foil to reduce a displacement of the foil positions. The foil is tightly held with three thin-supports with a thickness of 0.3 mm. We made the test model of a mirror housing, and found that the foil position was determined with σ~12μm.
We have developed compound refractive prism for cold neutrons. To prevent an increase in neutron absorption, we have developed prism array like a Fresnel lens. The prism characteristics were investigated with experimental and numerical simulation studies. We achieved transmission of 0.75 and refractive angle of 7.5 mrad for 15 neutrons with 49 layered prism array.