Scanning holographic microscopy with transverse resolution exceeding the Rayleigh limit and extended depth of focus

We demonstrate experimentally that the method of scanning holographic microscopy is capable of producing images reconstructed numerically from holograms recorded digitally in the time domain by scanning, with transverse and axial resolutions comparable to those of wide-field or scanning microscopy with the same objective. Furthermore, we show that it is possible to synthesize the point-spread function of scanning holographic microscopy to obtain, with the same objective, holographic reconstructions with a transverse resolution exceeding the Rayleigh limit of the objective up to a factor of 2 in the limit of low numerical aperture. These holographic reconstructions also exhibit an extended depth of focus, the extent of which is adjustable without compromising the transverse resolution. (c) 2005 Optical Society of America.