Holographic Optical Element Fiber Coupler For The Near Infrared

Abstract

We describe the possibility to use a single holographic optical element (HOE) for coupling between multimode optical fibers at a wavelength close to 1.3 μm. Dichromated gelatin is used as photosensitive medium for recording at 514 nm. Due to the large change of wavelength between recording and reconstruction of the FOE, the geometries of the experimental set up must be carefully choosen. First experimental results are presented, giving coupling losses of the device which is also designed to act as a wavelength division demultiplexer (for 4 different wavelengths centered on 1.3 μm, two consecutive wavelengths being separated by 30 nm).