The resonator is an important part of the laser oscillator. In general, it is very difficult to make a laser work ideally because it is quite difficult to adjust the two end mirrors of the resonator to a completely parallel state. Besides, when the cavity mirror of the resonator is slightly disturbed, the output of the laser will fluctuate greatly, even disappear. For all conventional plane-plane, plane-concave and concave-concave cavity lasers, these problems are inevitable. Poor prisms or cube-corner prisms have been used as the reflector of the laser resonator to improve the stability of the laser. In addition to alignment and power stability issues, the development of the movable resonator has special application values. The resonant beam charging (RBC) is a wireless power transfer technology which transfers power through the intra-cavity resonant beam. The mobility of the resonant cavity is the premise of the resonant beam charging system to realize the movable wireless power transmission. For the resonant beam charging system, the transmission power and efficiency when the output mirror moves along the axis of the resonant cavity have been demonstrated. However, the mobility of the resonant beam charging system along the horizontal direction needs further study.

Scientists have invented microrobots that can directly reach the site of disease to perform medical tasks. Microrobots-assisted in vivo drug delivery, release, and in situ surgery are therefore seen as very promising medical solutions. In recent years, more researchers are focusing on how microrobots can be truly applied for clinical therapy. Many in vivo experiments on small animals have also been carried out to validate and advance the in vivo application of the microrobots.

In a recent review published in Chinese Optics Letters (Z. Li, et al., Liquid Crystal Devices for Vector Vortex Beams Manipulation and Quantum Information Applications), the research group led by Prof. Yanqing Lu from Nanjing University discussed the functions and applications of typical Liquid crystal (LC) devices in recent studies on controlling the vector vortex beams (VVBs). They also reviewed the experimental advances on novel photonic applications in the quantum domain enabled by LC devices.

The plasmonic circuit has different forms, one of such forms is the one that consists of a silicon micro-ring. The silicon micro-ring has many uses and has been used for various applications by many researchers. Space-time function gives the description of a field that evolves with time and position and its boundaries give rise to singularities. The space-time function control has been used by many researchers for various purposes. The whispering gallery mode (WGM) comes into play when it is a wireless connection and can be applied in light fidelity (LiFi) network while for the cable connection signals are transmitted through cable and can be applied in optic fiber network. WGM generation is an important phenomenon, which results in the product of the micro-ring trapped light in the micro-ring circuit.