A new non-imaging angle measurement method based on an axicon is proposed in this paper. This method uses an axicon that can form a complex light spot with a clear edge and rich feature information after total internal reflection and refraction on the sloped face compared with convergent lenses, which can only form a blurry edge spot. According to the high sensitivity of the beam transformation of the axicon to the incident angle, light spot images with obvious feature variation can be easily obtained to achieve angle measurement with high accuracy. The method based on an axicon can meet the application requirements of multiple angle measurement ranges, and the structure is simple and compact. In the small-angle measurement experiment combined with a telescope module, the measurement resolution can reach 1′′, the mean absolute error is 0.0010°, and the relative error is within 0.25% in the measurement range of 1.6°.

A metrology method of x-ray optical elements based on an electromagnetic phase stepping x-ray grating interferometer with high slope accuracy is presented in this study. The device consists of an x-ray tube, a phase grating [Formula: see text] for modulating the incoming wavefront, and an absorption grating [Formula: see text] as a transmission mask to produce a broader moiré pattern for the x-ray camera. The focal spot of the microfocus x-ray source is shifted by a magnetic field from a solenoid coil. Electromagnetic phase stepping analysis is used to obtain a pixel-wise map of the wavefront phase distortion to replace the traditional precision mechanical scanning system, improving stability, speed, accuracy, and flexibility. The x-ray grating interferometer can be used as a feedback tool for evaluating the quality of optical elements and detecting defects caused by the x-ray beam or the x-ray optical elements in ordinary laboratories and mirror-processing centers without the need of scheduling synchrotron beam time.