Recent Advances in Adaptive Liquid Crystal Lenses

Abstract

An adaptive-focus lens is a device that is capable of tuning its focal length by means of an external stimulus. Numerous techniques for the demonstration of such devices have been reported thus far. Moving beyond traditional solutions, several new approaches have been proposed in recent years based on the use of liquid crystals, which can have a great impact in emerging applications. This work focuses on the recent advances in liquid crystal lenses with diameters larger than 1 mm. Recent demonstrations and their performance characteristics are reviewed, discussing the advantages and disadvantages of the reported technologies and identifying the challenges and future prospects in the active research field of adaptive-focus liquid crystal (LC) lenses.

<p>Historical Development, Applications and Advances in Materials Used in Spectacle Lenses and Contact Lenses</p>

“…These lenses correct refractive error by reversibly altering either the refractive index or lens shape. 35 Liquid crystal (LC) designs combine properties of both crystalline solids and liquids, 35 and have received much attention especially in the correction of presbyopia. 36 In its solid state, the LC molecules are in regular order and held in fixed positions.…”

Artificial Organic Skin Wets Its Surface by Field-Induced Liquid Secretion

“…To reallocate the liquid by an RF electric field, we employ the mechanism of dielectric diffusion, which describes the interaction between the electric field and a medium with inhomogeneous dielectric constant. 17 Similar to the switching of liquid dielectric lenses, [18][19][20] the dielectric force exerting on the liquid media can be expressed as…”

Chiral Liquid Crystal Lenses Confined in Microchannels

“…Importantly, they frequently occur at the same location as FCDs upon heating, with a central +1 topological defect pinned in the channel through the phase transition. These structures resemble cholesteric defects such as torons [ 3 , 4 ] or toron-like [ 5 , 6 ] structures, which can form in the presence of homeotropic anchoring. Measuring the focal length as a function of temperature, as the temperature is decreased from the cholesteric to the smectic phase, we notice that the lenses show a discontinuity between the two phases.…”

“…While liquid crystal (LC) technology is widely associated with displays and spatial light modulators [ 1 , 2 ], the LC potential for other optical elements has been only partly explored. In particular, LC-based lenses have shown increasing promise in the past years due to their potential for external actuation, low energy switching, polarization sensitivity, and tunability [ 3 , 4 , 5 ]. Moreover, LCs offer the possibility to create lenses in the micro-scale, which would otherwise require complex manufacturing.…”