Spatial light modulators

Spatial Light Modulators (SLMs) are quasiplanar devices, allowing for the modulation of the amplitude, phase and polarization, or a combination of these parameters of an incident light beam according to the two spatial dimensions of the modulator. SLMs are employed in many different fields and are the subject of continuous technological development.

The polymer converter for effectively connecting polymer with silica optical fibres

We present a micrometer-size polymer converter (microbridge) for connecting polymer optical fibres with silica fibres. The procedure of preparing such microstructure is based on a process of photopolymerization. A polymer converter grows as an extension of the fibres’ cores due to a self-guiding effect of the light beam in a photopolymerizable medium. Since the polymer microbridge has refractive index greater inside than outside, such a structure works as a waveguide leading the light beam between connected optical fibres. By selection of time of light exposition to the mixture and optical power of the incident light beam, it is possible to obtain a polymer converter with very good optical and mechanical characteristics. Possibility of using polymer microbridges grown directly from the fibres’ core as coupling elements between silica and polymer fibres is a good alternative for obtaining permanent coupling of such fibres.

Enhancement of diffraction efficiency for optical gratings

A method to increase the diffraction efficiency for optical gratings is proposed. Using a simple glass plate sitting parallel to the top of a grating surface, one can form an air gap between the surfaces of the grating and the glass plate to reflect a grazing-incident light beam and make diffraction through multiple reflection of the beam between the grating and glass plate surfaces. As a result, this device can efficiently enhance the grating efficiency by diffracting the input beam energy into various diffraction orders. PACS Nos.: 07.60-j, 42.25Fx, 42.40Lx, 42.79Dj, 42.40Fg

The Influence of a Static Magnetic Field on the Optical Properties of Chiral Molecules

A static magnetic field parallel to the direction of propagation of an incident light beam causes a small shift in the value of the refractive index and, correspondingly, of the absorption coefficient of a chiral molecule. This shift is opposite for enantiomers. However, it occurs for arbitrarily polarized light and is therefore not a circular differential effect.