Tunable Focusing Liquid Crystal Lenses: The Challenges and the Opportunities.

The utilization of liquid crystals (LC) as materials has enabled the enlargement of lenses with the potential to alter their focus. Tunable LC lenses with adjustable focus are essential for optical imaging, sensing, and detection devices. This technology offers many benefits, such as the ability to adjust focus, operate with low power, and be easily made. Its compact structure and stability are also advantages. Adding polymer additives to pure LC systems enhances their capabilities and provides more flexibility and functionality. This review explores ways to enhance the performance of tunable LC lenses, including image quality, speed, optical power, and device fabrication. Especially, enhancements include a switchable focus range, wider viewing angles, and a flexible lens. The challenges in fabricating and controlling LC methods have significant implications for many potential applications. The discovery of new LC materials and lens designs will further highlight these implications.