A comprehensive review of optical diffusers: progress and prospects

Optical diffusers made of polymer composite materials are vital for many photonic and optoelectronic applictions such as backlight unit (BLU) in liquid crystal displays (LCDs), light extraction unit of organic light emitting diodes (OLEDs), and solar cells. We have described the types of optical diffusers, the theory and measurement of light scattering, some common approaches for fabricating optical diffusers, the potential applications and recent developments of optical diffusers containing optical physical unclonable functions (PUFs), optical random number generators, passive stretchable radiative coolers, diffuser -based deep neural networks, lensless cameras or imaging systems, and three dimensinonal (3D) displays including two dimensional (2D)/3D switchable displays, which provide effective ways for designing high-performance optical films in the applications of optical devices. To satisfy the requirements for applications in stretchable optoelectronics and optomechanics, tunable optical diffusers stimulated by electric field, heat, light, mechanical field, or ultrasound attract much attention. Polymer/liquid crystal (LC) composite films with tunable light transmittance, haze, and diffusing intensity have been firstly provided and set a great foundation for the next generation of flexible and switchable optical diffusers.

Automated summary

Optical diffusers made of polymer composite materials are vital for various photonic and optoelectronic applications such as LCDs, OLEDs, and solar cells. This article provides a comprehensive overview of different types of optical diffusers, the theory and measurement of light scattering, fabrication methods, and recent developments in applications such as PUFs, random number generators, stretchable radiative coolers, deep neural networks, lensless cameras, and 3D displays. Additionally, tunable optical diffusers stimulated by various stimuli have gained significant attention for their potential in stretchable optoelectronics and optomechanics.