A defect detection apparatus is provided that can inspect a measurement region of a target object at one time and without inconsistencies arising within the measurement region. A defect detection apparatus 10 includes: a generation unit (signal generator 11 and vibrator 12) for generating an elastic wave in a target object S; an illumination unit (pulsed laser light source 13 and illumination light lens 14) for performing stroboscopic illumination onto a measurement region of a surface of the target object S; and a displacement measurement unit (speckle shearing interferometer 15) for collectively measuring displacements in a normal direction at each point of the measurement region with respect to at least three mutually-different phases of the elastic wave by controlling a phase of the elastic wave and a timing of the stroboscopic illumination. Defects in the measurement region are detected based on the displacements in the normal direction at each point of the measurement region with respect to at least three phases that are obtained by the displacement measurement unit.

A vibration measurement device includes: a vibration-inducing section; a laser source; a scanning section for illuminating a partial area of a measurement area on an object with laser light and moving the illumination area; an illumination control section for sequentially illuminating each point within the measurement area with an illuminating duration equal to or shorter than one third of the vibration period; a displacement measurement section for measuring, for each point within the measurement area, an interfering light obtained by splitting an object light from the object into two bundles of light to measure a relative displacement in a back-and-forth direction between two closely-located points within the measurement area; and a vibration state determination section for determining the state of vibration of the entire measurement area, based on the relative displacement in the back-and-forth direction between two closely-located points at each point within the measurement area.

Disclosed are systems and methods to extract information about the size and shape of an object by observing variations of the radiation pattern caused by illuminating the object with coherent radiation sources and changing the wavelengths of the source. Sensing and image-reconstruction systems and methods are described for recovering the image of an object utilizing projected and transparent reference points and radiation sources such as tunable lasers. Sensing and image-reconstruction systems and methods are also described for rapid sensing of such radiation patterns. A computational system and method is also described for sensing and reconstructing the image from its autocorrelation. This computational approach uses the fact that the autocorrelation is the weighted sum of shifted copies of an image, where the shifts are obtained by sequentially placing each individual scattering cell of the object at the origin of the autocorrelation space.

Disclosed are systems and methods to extract information about the size and shape of an object by observing variations of the radiation pattern caused by illuminating the object with coherent radiation sources and changing the wavelengths of the source. Sensing and image-reconstruction systems and methods are described for recovering the image of an object utilizing projected and transparent reference points and radiation sources such as tunable lasers. Sensing and image-reconstruction systems and methods are also described for rapid sensing of such radiation patterns. A computational system and method is also described for sensing and reconstructing the image from its autocorrelation. This computational approach uses the fact that the autocorrelation is the weighted sum of shifted copies of an image, where the shifts are obtained by sequentially placing each individual scattering cell of the object at the origin of the autocorrelation space.