Rapid quantitative phase imaging for partially coherent light microscopy

Abstract

Abstract:Partially coherent light provides promising advantages for imaging applications. In contrast to its completely coherent counterpart, it prevents image degradation due to speckle noise and decreases cross-talk among the imaged objects. These facts make attractive the partially coherent illumination for accurate quantitative imaging in microscopy. In this work, we present a non-interferometric technique and system for quantitative phase imaging with simultaneous determination of the spatial coherence properties of the sample illumination. Its performance is experimentally demonstrated in several examples underlining the benefits of partial coherence for practical imagining applications. The programmable optical setup comprises an electrically tunable lens and sCMOS camera that allows for high-speed measurement in the millisecond range.

Fast control of temporal and spatial coherence properties of microscope illumination using DLP projector

“…[17][18][19][20][21][22] The developed techniques can be extended to the visible wavelength range to obtain quantitative phase imaging with a brightfield microscope under Khöler illumination, see. 5,7,9,[23][24][25] For instance, inspired by the method proposed in, 21 we have developed an iterative technique that is able to retrieve both the phase delay caused by the object and degree of spatial coherence of the microscope illumination beam.…”

“…In particular, speckle-noise and cross-talk reduction allow for accurate quantitative phase imaging of specimens, see for example. [3][4][5][6][7] Other relevant advantage in controlling the light coherence state is that one may achieve subwavelength spatial resolution when the specimen is illuminated by an evanescent field with its spatial coherence adjusted at subwavelenght scales. 8 An illumination or probe beam with adjustable coherence properties according to the standing application opens up new and promising perspectives.…”

Diffraction phase microscopy: monitoring nanoscale dynamics in materials science [Invited]

“…QPI has been performed using a variety of sources including lasers in both the visible and infrared (IR) regimes [27]. Broadband techniques using light emitting diodes (LEDs), super-continuum lasers, and standard halogen lamp illumination have also been demonstrated [20,[28][29][30]. White light methods generally exhibit lower noise due to the lower coherence, both spatially and temporally, which reduces noise mechanisms such as laser speckle.…”

Partially coherent phase imaging with simultaneous source recovery

“…Neglecting pupil filtering effects, we can therefore treat the forward model in the same way as the coherent case, but with an extra convolution step for each defocus distance. This convolution model was first introduced for phase recovery in [21] and later used in other methods [37,38].…”