MERTIS: Optics manufacturing and verification

The MERTIS reflective infrared optics can be beneficial implemented as diamond turned aluminium mirrors coated with a thin gold layer. The cutting processes allow the manufacturing of both, the optical surface and mechanical interfaces, in tight tolerances. This is one of the major advantages of metal optics and was consequently used for the MERTIS sensor head optics. This paper describes the entire process chain of the MERTIS spectrometer optics including the manufacturing methods for the mirrors and for the spherical grating, the coating with sputtered gold for infrared reflectivity as well as the alignment and the verification of the spectrometer optics

Realization of Free‐Space Long‐Distance Self‐Healing Bessel Beams

A new approach for generating long‐distance self‐healing Bessel beams, which is based on a ring‐shaped (annular) lens and a spherical lens in 4f‐configuration, is reported. With this, diffraction‐free light evolution of a zeroth order Bessel beam over several meters is shown and available scaling opportunities that surpass current technologies by far are discussed. Furthermore, it is demonstrated how this setup can be adapted to create Bessel beam superpositions, realizing the longest ever reported optical conveyor beam and helicon beam, respectively. Last, the self‐healing capabilities of the beams are tested against strong opaque and non‐opaque scatterers, which again emphasizes the great potential of this new method

Moth-eye structures for reduction of Fresnel losses at THz components

The applicability of moth-eye structures to THz components is investigated. With the help of RCWA and effective medium theory, optimal structural parameters for one-dimensional and two-dimensional periodical surface-relief gratings are deduced. The required structural parameters are in such order of magnitude that they can be manufactured by ultra-precision machining directly into the surface of the substrate material. Benefiting is that plastic materials, which are preferred materials in THz spectral region, can be accurately manufactured by ultra-precision machining. The application of the moth-eye structures follows directly the primary shaping of the components by conventional manufacturing methods like turning and milling so that no additional materials are necessary. A comparison between several structures fabricated on planar plastic probes is given

Behavioral Health Training for Fire Rescue Personnel

In T.J. LeDuc (Chairperson), Surviving the Fire Service: A National Memorial Conference