Lateral shear interferometry with holo shear lens

Measurement of temperature and temperature profile of candle flame using holo-shear lens and Fourier fringe analysis technique

“…24,26,28,29,[31][32][33] Figure 1 shows the schematic of the experimental setup used for the recording of a holo-shear lens. It can function both as negative and positive spherical lens.…”

“…Optical interferometric techniques provide fullfield temperature data inside transparent hot objects. [21][22][23][24][25][26][27][28][29][30][31][32][33] A holo-shear lens is a simple device which can be used as lateral shear interferometer. These techniques, if used properly, are highly accurate and precise.…”

“…These techniques are of a noncontact and noninvasive type. 24,26,28,29,[31][32][33] In this paper, a holo-shear lens made on dichromated gelatin (DCG) is used as a lateral shear interferometer for the measurement of the temperature and temperature profile of a gaseous (candle) flame. A large number of optical interferometric methods such as classical interferometry, 1,2 holographic interferometry, 3-6 moiré deflectometry, 7 Talbot interferometry, [8][9][10] speckle shearing interferometry, 11,12 lateral shearing interferometry, [13][14][15] Lau phase interferometry, 16 and digital holographic interferometry 17,18 have been widely used for the measurement of the temperature field in gaseous flames and to study the phase objects.…”

Spatially multiplexed X-Y lateral shear interferometer with varying shears using holographic lens and spatial Fourier transform

“…The interferometer operates in a convergent beam where the focus of the beam lies at the plane of the grating. In later years, a double frequency grating was generated by using holographic shear lens [4][5][6]. One of the problems associated with convergent beam optical testing technique is that it is limited by the quality of the collimating beam before the test lens.…”

Novel and simple lateral shear interferometer with holographic lens and spatial Fourier transform

“…It has been common to do qualitative analysis with lateral shear interferometer and of late there are several articles where quantitative measurements are made using phase shifting. [4][5][6][7][8][9] In general, phase shifting is performed in a HSL, and holographic double grating (HDG) is done by translation of the grating. Shearing has also been performed in a collimated beam using two holographic gratings that are spaced along the direction of the beam.…”