Tunable Diffraction Grating

Abstract

The invention is directed to a tunable diffraction grating (1) with optically active elements (5) arranged at a distance (A) next to each other. The optically active elements (5) are displaceable relative to each other in a lateral direction (x, y) and mechanically interconnected to a layer (4), which is made out of a deformable material. A deformation of the layer (4) in a direction (z) in general perpendicular to the lateral direction (x, y) causes a change in the relative distance (A) of the optically active elements (5).

Description

FIELD OF THE INVENTION[0001]The invention lies in the field of diffraction gratings, especially tunable diffraction gratings with a significant spectral tuning range.BACKGROUND OF THE INVENTION[0002]A diffraction grating is an optical element that consists of a reflecting or trans-parent substrate whose surface contains fine, parallel grooves or rulings that are equally spaced. When light is incident on a diffraction grating, diffractive and mutual interference effects occur and light is reflected or transmitted in discrete directions called orders. Because of their dispersive properties, gratings are commonly used in monochromators and spectrometers. These devices were first manufactured by German physicist Joseph von Fraunhofer in 1821.[0003]Diffraction gratings have been a research topic for many decades. At the beginning, the design and the functional principle of the gratings were of major interest. In recent years, tunable diffraction gratings became popular, which allow to mo...

AI Technical Summary

Benefits of technology

[0042]A first class of EAPs can be summarized as dielectric electroactive polymers (DEAP) wherein actuation is caused by electrostatic forces between electrodes. The electrodes are in general arranged opposite to each other on either side of a deformable polymeric material. When voltage is applied the opposite electrodes are attracted to each other and the in-between the electrodes arranged polymeric material is compressed. Due to poisson's ratio the compressed material expands in a perpendicular direction (late

Problems solved by technology

One major problem is the fact that the diffraction gratings are not continuously tunable without employing a complicated macroscopic rotation mechanism or expensive and complicated microscopic mechanical actuators.

However, from the prior art it is not known to tune a gratin

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