Demonstration of focus-tunable diffractive Moiré-lenses.

In an earlier publication [Appl. Opt. 47, 3722 (2008)] we suggested an adaptive optical lens, which consists of two cascaded diffractive optical elements (DOEs). Due to the Moiré-effect the combined optical element acts as a Fresnel zone lens with a refractive power that can be continuously adjusted by a mutual rotation of the two stacked DOEs. Here we present an experimental realization of this concept. Four designs of these Moiré-DOEs (MDOEs) were fabricated in thin (0.7 mm) glass slides by lithography and subsequent etching. Each element was realized as a 16 phase level DOE designed for 633 nm illumination. Our experimental investigation shows that the Moiré-lenses have a broad adjustable refractive power range with a high efficiency, which allows one to use them for flexible beam steering and for imaging applications.

[1]  Zbigniew Jaroszewicz,et al.  Diffractive elements of variable optical power and high diffraction efficiency. , 1993, Applied optics.

[2]  Fook Siong Chau,et al.  Liquid tunable diffractive/refractive hybrid lens. , 2009, Optics letters.

[3]  Equilateral hyperbolic moiré zone plates with variable focus obtained by rotations. , 2005, Optics express.

[4]  Robert Brunner,et al.  New solutions to realize complex optical systems by a combination of diffractive and refractive optical components , 2003, SPIE Optics + Photonics.

[5]  A. Lohmann.  A new class of varifocal lenses. , 1970, Applied optics.

[6]  S Bara,et al.  Determination of basic grids for subtractive moire patterns. , 1991, Applied optics.

[7]  Johannes Ruoff,et al.  Design concepts for broadband high-efficiency DOEs , 2008 .

[8]  N. George,et al.  Hybrid diffractive-refractive lenses and achromats. , 1988, Applied optics.

[9]  Sergio Barbero,et al.  Adjustable-focus lenses based on the Alvarez principle , 2011 .

[10]  Sergio Barbero.  The Alvarez and Lohmann refractive lenses revisited. , 2009, Optics express.

[11]  Shin-Tson Wu,et al.  Dielectric liquid microlens with well-shaped electrode. , 2009, Optics express.

[12]  Li Guoqiang,et al.  Adaptive Lens. , 2010, Progress in optics.

[13]  Monika Ritsch-Marte,et al.  Adjustable refractive power from diffractive moiré elements. , 2008, Applied optics.

[14]  M. Cagigal,et al.  Focal modulation using rotating phase filters. , 2010, Optics express.

[15]  T. Nose,et al.  A liquid crystal microlens obtained with a non-uniform electric field , 1989 .

[16]  Shin-Tson Wu,et al.  Liquid crystal lens with large focal length tunability and low operating voltage. , 2007, Optics express.

[17]  L. J. Summers,et al.  Diffractive Alvarez lens. , 2000, Optics letters.

[18]  M. R. Dodge,et al.  Tunable-focus flat liquid-crystal diffractive lens. , 2010, Optics letters.

[19]  Shin-Tson Wu,et al.  Adaptive-Focus Lenses , 2008 .

[20]  E. G. Ezhov,et al.  Diffractive-refractive correction units for plastic compact zoom lenses. , 2012, Applied optics.

[21]  J M Burch,et al.  Varifocal moiré zone plates for straightness measurement. , 1977, Applied optics.