Novel liquid-crystal devices are described that generate linearly polarized light with axial symmetry; the beam propagation axis is the symmetry axis. Such light fields can be characterized by a polarization order number P. For example, P = 1 fields represent radially or azimuthally polarized light. The reorientation of the polarization orientation in these polarization converters is due to the twisted nematic effect and the effect of lambda/2 wave plates. A single polarization converter can generate fields of orders 1 and 2. It is shown that one can in principle generate fields of any integral order P by cascading such elements. Devices that generate P = 1 fields are achromatic and can be used as polarization axis finders or as versatile tools for studying birefringent or polarizing materials.

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Tunable, flashlamp-pumped laser properties are discribed for the crystal Cr:LiSrAlF6 (Cr:LiSAF) in both long pulse and Q-switched modes of operation. Slope efficiencies of 5%, overall efficiency of 3%, and a tuning range from 780 to 1010 nm are reported.

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A new concept for generating visual effects with metallized gratings is introduced. Shadow evaporation of aluminum onto dielectric gratings is shown to produce strongly asymmetric color effects. Zero‐order effects are combined with ±first‐order transmission in the present structures to generate not only polarization but also orientation‐dependent colors. We show that a wide palette of colors can be obtained by simply scaling the parameters of the dielectric base grating. The present approach therefore enables the fabrication of entire asymmetric images in a two‐step process. Additionally, a floating screen film is created by placing the grating at an increased distance to the light source. The present structures could find applications as security or decorative elements and are well suited for mass production using high‐throughput techniques such as roll‐to‐roll fabrication.