Trifocal lens system with liquid crystal Fresnel lens

Abstract

In this paper, we present the construction of a trifocal lens system by combining a liquid-crystal (LC) lens and an ordinary lens. The focusing properties of the proposed system can be controlled by changing the polarization state of the incident light wave. The characteristics of the fabricated lens system were evaluated and it was confirmed that the system converged light at three focal points. It was also confirmed that the intensity of the light collected at each focal point could be regulated by controlling the polarization state of incident light and the retardation of the LC Fresnel lens in the proposed trifocal lens system.

Liquid Crystal Optical Device

“…In recent years, some cases include refractive Fresnel lenses [167] and diffractive Fresnel lenses, in which the zones are made by confining ferroelectric liquid crystals (FLCs) in multiple microscopically defined photo-aligned alignment domains [168] (Figure 11a,b); by multi-electrodes [169]; polymer-dispersed liquid crystal [170]; by a 90 • twisted-nematic liquid crystal (LC) cell with a photoconductive polymer layer [171]; by using a photoconductive polymer layer and a Sagnac interferometer [172]; by a P6CB alignment layer (orientation direction also controlled along the polarization direction of UV light) and an interferometric setup [173]; by a patterned hybrid photo-aligned nematic dual frequency LC [174]; by Polymer-Stabilized Blue Phase (PSBP) LC zones [175][176][177] (the lenses being also polarization-independent). In these cases, the thickness is considerably reduced (between 1.5 um to 12 um), and therefore, the switching is fast.…”

Recent Advances in Adaptive Liquid Crystal Lenses

“…The main disadvantage of these designs is the low diffraction efficiency obtained (around 30-40% for a binary phase lens). In recent years, some cases include refractive Fresnel lenses [167] and diffractive Fresnel lenses, in which the zones are made by confining ferroelectric liquid crystals (FLCs) in multiple microscopically defined photo-aligned alignment domains [168] (Figure 11a,b); by multi-electrodes [169]; polymer-dispersed liquid crystal [170]; by a 90° twisted-nematic liquid crystal (LC) cell with a photoconductive polymer layer [171]; by using a photoconductive polymer layer and a Sagnac interferometer [172]; by a P6CB alignment layer (orientation direction also controlled along the polarization direction of UV light) and an interferometric setup [173]; by a patterned hybrid photoaligned nematic dual frequency LC [174]; by Polymer-Stabilized Blue Phase (PSBP) LC zones [175][176][177] (the lenses being also polarization-independent). In these cases, the thickness is considerably reduced (between 1.5 um to 12 um), and therefore, the switching is fast.…”

A flexible retinal device with CMOS smart electrodes fabricated on parylene C thin-film and bioceramic substrate

“…[8][9][10][11][12][13] Retinal-stimulated artificial vision systems are classified into three categories according to the implantation position of the stimulation electrode in the eye: epiretinal stimulation, [14][15][16][17] subretinal stimulation, [18][19][20][21][22][23] and suprachoroidal-transretinal stimulation methods (STS). [24][25][26][27][28][29] As epiretinal and subretinal stimulation devices, Argus-II and Alpha AMS have been developed, which improve visual acuity in implanted subjects. 16,18) We developed a device for suprachoroidal transretinal stimulation in this study.…”