Structured light three-dimensional (3D) reconstruction has been widely used in medicine, aerospace and other industrial fields. As one of the 3D reconstruction methods of structured light, phase-shifting profilometry (PSP) has attracted much attention due to its high accuracy and robustness. PSP is used to obtain the 3D shape of objects by collecting and solving the fringe patterns projected onto the object surface with phase information. The phase information of PSP has periodic phase ambiguity of (0-2π). The traditional method requires additional fringe patterns to determine the fringe period, which undoubtedly increases the time cost and limits the area of usage scenarios. With the increased of application scenarios such as dynamic object reconstruction and real-time object scanning in industry, traditional PSP cannot meet the requirements.

Chirality is a fundamental property in nature. It manifests in various physical, chemical, and biological processes. Chiral molecules do not have a symmetry plane and exist in pairs of left- and right-handed enantiomers. Chiral molecules show strong enantiomeric selectivity. For example, most isomers of chiral drugs exhibit marked differences in biological activities. Therefore, it is vital to identify the molecular chirality. Furthermore, detection of the chiral dynamics in the femtosecond and sub-femtosecond scales can help people understand the underlying physical mechanisms of the chemical reactions.

With the increasing human underwater activities, such as environmental monitoring, underwater exploration, and scientific data collection, it is urgent to develop a safe, reliable, and high-speed underwater wireless communication technology. As an important supplementary technology for underwater wireless networks, underwater wireless optical communication (UWOC) has attracted the attention of many researchers in recent years due to its advantages of high bandwidth, low latency, and low power consumption. However, due to the open characteristic of UWOC systems, the gradual diffusion of the propagating beam in long distances, and the scattering effect of water, the transmission data is highly susceptible to detection, interception, and monitoring by illegal users, which leads to information leakage. From a wireless coverage perspective, security and privacy are equally important as data rate. For certain special cases, such as UWOC systems deployed in unattended, opaque, or even hostile waters or underwater multi-user communications, the security of information transmission is even more important than the data rate. Hence, the security enhancement of UWOC turns into a critical and unavoidable issue in practical application.

Structural color originates from the interaction between light and periodic submicron structures and has led to many unique functions in nature, inspiring the development of material science. In sensing changes in the external environment, animals use color changes to transmit signals and accomplish behaviors such as communication, camouflage, vigilance, and courtship. Responsive photonic crystals are considered to be one of the best artificial materials for preparing color-changing functions, i.e., when induced by external stimuli, photonic crystals change their own periodic structure to modulate the properties of light waves, producing color changes in visual effects associated with wavelength changes. Among them, the cholesteric liquid crystal (CLC) exhibits unique selective reflective properties due to its self-assembled helical structure forming a periodic arrangement of dielectric constant and refractive index, is endowed with advantages such as polarization-dependent generation of structural color and dynamic tunability, and is rapidly developing in research fields such as dynamic display, information storage, and optical security. People have been changing the working wavelength and reflectivity by using optical, electrical and thermal responsive chiral molecules, multilayer composite structures, phase transitions and many other methods. However, there are still problems such as easy destabilization and limited regulation mechanisms, so it is still a challenge to design and prepare reflective liquid crystal photonic devices with multiple responses, real-time reconfigurability, and dynamic broadband tunability.