Abstract: A long range laser illuminator is disclosed that is suitable for providing illumination for camera systems at ranges up to approximately 20 km. The illuminator incorporates a diverger that allows for a compact, low F-number optical arrangement that improves eye safety by reducing the power density across a primary optical element, such as a spherical or parabolic mirror. The diverger may be located at an end of an optical fiber feed, or between a pair of optical fibers. The diverger may incorporate a diffuser, such as a “top hat” diffuser. The optical fiber feeds may be highly multi mode, to provide for a more even illumination. The illuminator incorporates means for altering a focus of the output light beam, to allow an illuminated spot size to be altered. The illuminator is particularly suitable for use at night, where it may be used alongside a camera system.

Abstract: A long range laser illuminator is disclosed that is suitable for providing illumination for camera systems at ranges up to approximately 20 km. The illuminator incorporates a diverger that allows for a compact, low F-number optical arrangement that improves eye safety by reducing the power density across a primary optical element, such as a spherical or parabolic mirror. The diverger may be located at an end of an optical fibre feed, or between a pair of optical fibres. The diverger may incorporate a diffuser, such as a “top hat” diffuser. The optical fibre feeds may be highly multi mode, to provide for a more even illumination. The illuminator incorporates means for altering a focus of the output light beam, to allow an illuminated spot size to be altered. The illuminator is particularly suitable for use at night, where it may be used alongside a camera system.

Abstract: Wavefront sensing apparatus comprises a beam splitter (106) for combining a wavefront to be characterised (105) with a frequency-shifted plane wavefront (111) and a bundle of optical fibres (112) arranged to detect the combined beam at a plurality of positions across the combined beam. Output from individual fibres of the bundle are detected to produce corresponding heterodyne signals, the phases of which are extracted by demodulation. By fitting the extracted phases to an assumed functional form for the phase of the wavefront to be characterised, the piston, tip, tilt and radius of curvature phase parameters of the wave-front to be characterised may be found at the position of the fibre bundle. In contrast, prior art methods of wavefront characterisation only allow the piston phase of the wavefront to be characterised to be obtained.