Abstract: An apparatus having a waveguide and a freeform collimating lens. The waveguide is characterized by a waveguide axis and a planar end having a normal axis that is inclined at an end angle that is greater than 0 degrees with respect to the waveguide axis. The freeform collimating lens collimates light leaving the planar end of the waveguide into a collimated light beam characterized by a beam direction that is parallel to the waveguide axis. The apparatus inhibits reflections from the planar end of the waveguide from propagating back down the waveguide while providing a collimated light beam having a direction parallel to the axis of the waveguide.

Abstract: Apparatus and methods for spectral analysis of a sample are described, for example for carrying out Raman or other optical or spectroscopic analysis of samples such as pharmaceutical dosage forms, including oral solid dosage forms such as tablets or capsules. Such apparatus may comprise delivery optics arranged to direct probe light to a delivery region of the sample, collection optics arranged to collect probe light scattered from a collection region of the sample, and a spectrometer having an entrance port, the spectrometer being arranged to receive the collected probe light from the collection optics at the entrance port of the spectrometer, and to detect spectral features in the received probe light. In particular, the collection optics may comprise Koehler integration optics arranged to process the collected probe light such that the collected light from each point of the collection region is distributed across the entrance port of the spectrometer.

Abstract: One example of a solar voltaic concentrator has a primary Fresnel lens with multiple panels, each of which forms a Kohler integrator with a respective panel of a lenticular secondary lens. The resulting plurality of integrators all concentrate sunlight onto a common multi-junction photovoltaic cell. The integrators provide matching illumination in the different wavebands required by the different junctions. Luminaires using a similar geometry are also possible.