GENERAL ENQUIRIES: Tel: + 27 12 841 2911 | Email: callcentre@csir.co.za

Browsing by Author "Forbes, A"

Sort by: Order: Results:

  • Naidoo, Darryl; Mafusire, C; Forbes, A (South African Institute of Physics, 2009-07)
    An optical aberration is a distortion of an image as compared to the object due to defects in an optical system
  • Forbes, A; Botha, LR; Du Preez, N; Drake, TE (Acad Science South Africa A S S AF, 2006-07)
    Laser ultrasonic is currently the optimal method for non-destructive testing of composite materials in the aerospace industry. The process is based on a laser-generated, ultrasound wave which propagates inside the composite. ...
  • Forbes, A; Botha, LR; du Preez, N; Drake, T (2006-02)
    Laser ultrasonics is the present state-of-the art method for non-destructive testing of composite materials in the aerospace industry. The process is based on an IR laser generating an ultrasound wave that propagates inside ...
  • Mudau, AE; Mwakikunga, BW; Brink, N; Willers, CJ; Forbes, A; Shikwambana, L; Govender, M (SAIP 2010, 2010-09)
    To determination the temperature using infrared cameras, the following issues need to be addressed, the emissivity of the object and atmospheric path effects. The later is negligible in the setup used. In this paper authors ...
  • Long, CS; Loveday, PW; Forbes, A (HVG Hanseatische Veranstaltungs-GmbH, 2008-06)
    An intra-cavity adaptive mirror is developed for compensation of time-dependent phase aberrations to a laser beam, such as those caused by thermal lensing. The unimorph-type device consists of a metallic disc, with a mirror ...
  • Ngcobo, S; Litvin, I; Burger, L; Forbes, A (SPIE Proceedings, 2014-02)
    In this paper we outline a simple laser cavity which produces customised on-demand digitally controlled laser modes by replacing the end-mirror of the cavity with an electrically addressed reflective phase-only spatial ...
  • Mhlanga, T; Trichili, A; Dudley, Angela L; Naidoo, Darryl; Zghal, M; Forbes, A (SPIE, 2014-10-02)
    High-capacity data transmission has been implemented using single channel optical systems. This technique is limited and soon it will be unable to ful ll the growing needs for higher bit rate data transmission. Hence multi-mode ...
  • Ngcobo, S; Litvin, I; Burger, L; Forbes, A (Nature Publishing Group, 2013-08)
    Customizing the output beam shape from a laser invariably involves specialized optical elements in the form of apertures, diffractive optics and free-form mirrors. Such optics require considerable design and fabrication ...
  • Forbes, A; Ngcobo, S; Burger, L; Litvin, IA (SPIE, 2014-02)
    In this paper we will outline our recent advances in all-digital control of light. Importantly, we will outline how to create a so-called “digital laser”, where a conventional laser mirror is replaced with a phase-only ...
  • Burger, L; Litvin, I; Forbes, A (SAIP, 2012-07)
    We describe the performance of twisted nematic liquid crystal (TNLC) spatial light modulators (SLMs) when used for intracavity beam shaping.
  • Dudley, Angela L; Forbes, A (2014-05)
    This study reports on the presentation of the second international conference on applications of optics and photonics: Digitally controlling the ‘twist’ of light.
  • Litvin, IA; Ngcobo, S; Naidoo, Darryl; Ait-Ameur, K; Forbes, A (Optical Society of America, 2014-02)
    Laguerre–Gaussian beams with a nonzero azimuthal index are known to carry orbital angular momentum (OAM), and are routinely created external to laser cavities. The few reports of obtaining such beams from laser cavities ...
  • Roro, Kittessa T; Mwakikunga, B; Tile, N; Yalisi, B; Forbes, A (Hindawi Publishing Corporation, 2012-05)
    Varying amounts of dispersed multiwalled carbon nanotubes in NiO have been used to develop composites that absorb the solar energy very well but lose very little through emission. Determination of absorptance, asol, and ...
  • Roro, Kittessa T; Tile, N; Yalisi, B; Forbes, A (2011-05)
    For efficient photo-thermal conversion of solar energy a spectrally selective solar absorber surfaces are widely used. An ideal selective surface should have a high absorptance (low reflectance) in the solar wavelength ...
  • Spangenberg, D-M; Dudley, Angela L; Neethling, P; Forbes, A; Rohwer, E (SPIE Proceedings, 2013-08)
    SLMs used for spatial modulation of lasers are often used in conjunction with very narrow bandwidth laser light where diffractive dispersion could be approximated as a constant. It is known that diffractive dispersion is ...
  • Litvin, IA; Forbes, A (The International Society for Optical Engineering, 2005)
    Bessel beams have gathered much interest of late due to their properties of near diffraction free propagation and self reconstruction after obstacles. Such laser beams have already found applications in fields such as ...
  • Dudley, Angela L; Mhlanga, T; Lavery, M; McDonald, A; Roux, FS; Padget, M; Forbes, A (Optical Society of America, 2013-01)
    We demonstrate the efficient sorter of Bessel beams separating both the azimuthal and radial components. This is based upon the recently reported transformation of angular to transverse momentum states. We separately ...
  • Mhlanga, T; Dudley, Angela L; McDonald, A; Roux, FS; Lavery, M; Padgett, M; Forbes, A (SPIE Digital llibrary, 2013-02)
    A procedure to efficiently sort orbital angular momentum (OAM) states of light, by performing a Cartesian to log-polar coordinate transformation which translates helically phased beams into a transverse phase gradient, ...
  • Trichili, A; Dudley, Angela L; Salem, AB; Ndagano, B; Zghal, M; Forbes, A (SPIE, 2015-08)
    The authors experimentally demonstrate an information encoding protocol using the two degrees of freedom of Laguerre Gaussian modes having different radial and azimuthal components. A novel method, based on digital holography, ...
  • Trichili, A; Salem, AB; Dudley, Angela; Zghal, M; Forbes, A (Optical Society of America, 2016-07)
    We experimentally demonstrate an efficient information transmission technique using Laguerre Gaussian (LG) modes. This technique is based on multiplexing and demultiplexing multiple LG modes with different azimuthal and ...