Fringe Projection Techniques : Whither we are ?
During recent years, the use of fringe projection techniques for generating three-dimensional (3D) surface information has become one of the most active research areas in optical metrology. Its applications range from measuring the 3D shape of MEMS components to the measurement of flatness of large panels (2.5 m × .45 m). The technique has found various applications in diverse fields: biomedical applications such as 3D intra-oral dental measurements [1], non-invasive 3D imaging and monitoring of vascular wall deformations [2], human body shape measurement for shape guided radiotherapy treatment [3, 4], lower back deformation measurement [5], detection and monitoring of scoliosis [6], inspection of wounds [7, 8] and skin topography measurement for use in cosmetology [9, 10, 11]; industrial and scientific applications such as characterization of MEMS components [12, 13], vibration analysis [14, 15], refractometry [16], global measurement of free surface deformations [17, 18], local wall thickness measurement of forced sheet metals [19], corrosion analysis [20, 21], measurement of surface roughness [22, 23], reverse engineering [24, 25, 26], quality control of printed circuit board manufacturing [27, 28, 29] and heat-flow visualization [30]; kinematics applications such as measuring the shape and position of a moving object/creature [31, 32] and the study of kinematical parameters of dragonfly in free flight [33, 34]; biometric identification applications such as 3D face reconstruction for the development of robust face recognition systems [35, 36]; cultural heritage and preservation [37, 38, 39] etc.