Liquid Lens with Large Focal Length Tunability Fabricated in a Polyvinyl Chloride/Dibutyl Phthalate Gel Tube

Abstract

Usually, an adaptive liquid lens only has a positive focal length, which severely limits its application in imaging and other fields. Therefore, a liquid lens consisting of polyvinyl chloride/dibutyl phthalate (PVC/DBP) gel, glycerol solution, and a glass substrate is proposed to extend the dynamic focal length range. A spherical tube is formed by the PVC/DBP gel under the effect of hydrostatic and surface tensions, which is used to restrict the glycerol solution. The PVC/DBP gel does not deform under the effect of an electric field, so the tangent line at the three-phase junction changes with the change of contact angle, which leads to an enlargement of the dynamic focal length range. At different voltage values, the proposed lens can be configured to work in three different schemes, namely, converging light, nondeflecting light, and diverging light. Here, the proposed lens has high imaging quality; the resolution is better than 114 lp/mm. A lens with a reconfigurable focal length holds great promise in diverse applications such as fluorescence detection, beam shaping, and adaptive optics.

Non-aqueous organic solution based on a large-aperture spherical electrowetting liquid lens with a wide tunable focal length range

“…In the blue area of Fig. 10, the apparent contact angle, the electrowetting contact angle and the additional spherical angle always maintain the relationship of eqn (18). Now the SELL changes from negative lens to positive lens.…”

“…[1][2][3][4][5][6][7][8][9][10] At present, liquid lenses can be divided into two categories according to the principle of operation: one is a non-electrically driven liquid lens. [11][12][13][14][15][16][17][18][19][20] Another is an electrically driven liquid lens. [21][22][23][24][25][28][29][30][31][32][33][34][35][36] Among the electrically-driven liquid lenses, the electrowetting liquid lens works by changing the curvature of the liquid-liquid (L-L) interface based on the electrowetting on dielectric (EWOD) effect.…”

Electrowetting of a Soft Elastic Gel

“…PVC gel is optically transparent, and it has been employed to fabricate responsive optical devices such as adaptive focus lenses and optical diffusers. ,, In the last section, based on the previous results, we demonstrate that we can tailor the electrowetting behavior of a PVC gel-based light diffuser by simply applying predeformation. The working principle of the tunable PVC gel-based light diffuser is illustrated in Figure a.…”

Optimal Control of Droplets on a Solid Surface Using Distributed Contact Angles

“…A second example are optical applications where liquid droplets act as flexible lenses with continuous refraction power ranges [11][12][13][14][15][16][17] . By adjusting their shape and position using active adjustment of the contact angles, the curvature and hence the focal length can be precisely tuned.…”

“…A second example are optical applications where liquid droplets act as flexible lenses with continuous refraction power ranges. − By adjusting their shape and position using active adjustment of the contact angles, the curvature and hence the focal length can be precisely tuned. This allows for interesting applications like a liquid lens in cameras; see the recent review by Mishra et al for details …”