We developed a new near-eye display measurement system using anthropomorphic vision imaging to measure the key parameters of near-eye displays, including field-of-view (FOV), angular resolution, eye box, and virtual image depth. The characteristics of the human eye, such as pupil position, pupil size variation, accommodation function, and the high resolution of the fovea, are imitated by the proposed measurement system. A FOV scanning structure, together with a non-vignetting image-telecentric lens system, captures the virtual image from the near-eye display by imitating human eye function. As a proof-of-concept, a prototype device was used to obtain large-range, high-resolution measurements for key parameters of near-eye displays.

To reduce the afterpulsing in single photon detection based on avalanche diodes, an advanced passive quenching circuit for operation in free-running mode is developed. The measurement setup is designed. The dark count rate (DCR) and afterpulsing of Single photon avalanche diodes (SPADs) are measured. The results show that the new passive quenching circuit has a better afterpulsing performance compared to traditional circuits.

Compared to traditional manual-operation method for tunnel-wall deformation measurement, DCRP (Digital Close Range Photogrammetry) technique based on non-metric digital camera is a new emerging and more effective non-contact measurement method. In practical applications, the deformation parameter measurement jobs are throughout the entire process of the tunnel construction to ensure the safety of the project. There are urgent requirements for portability and miniaturization performances of the measurement system to reduce the interaction of measurement job and project construction. A configurable 3D control field equipment was presented, the control points of which could be freely configured according to the practical work conditions and do not need to be re-calibrated. A novel portable tunnel-wall deformation measurement system based on the non-metric digital camera and DLT algorithm was set up. Experimental results showed that the precision of the system for a large section tunnel-wall deformation measurement is better than 0.1‰. The system presented in the paper has the advantages of portability and miniaturization, as easy to implement fast and in-situ tunnel-wall deformation measurements.

Time delay estimation is a key technology of array signal processing, which is designed to estimate the time delay of the sound source signal reaches different sensor. Because of differences in the weighting function method, existing methods of generalized cross-correlation time delay estimation have their own anti-noise and anti-reverberation characteristics. In this paper, the existing various delay estimation algorithm comprehensive is compared, which reveals their advantages and disadvantages, and further improved direction of time delay estimation algorithm is given.

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