A method for obtaining a high resolution image of objects contained within a sample is disclosed that combines pixel super-resolution and phase retrieval techniques into a unified algorithmic framework that enables new holographic image reconstruction methods with significantly improved data efficiency, i.e., using much less number of raw measurements to obtain high-resolution and wide-field reconstructions of the sample. Using the unified algorithmic framework, twin image noise and spatial aliasing signals, along with other digital holographic artifacts, can be interpreted as noise terms modulated by digital phasors, which are all analytical functions of the imaging parameters including e.g., the lateral displacement between the hologram and the sensor array planes (x, y shifts), sample-to-image sensor distance (z), illumination wavelength (), and the angle of incidence (,).

A system for three dimensional imaging of an object contained within a sample includes an image sensor, a sample holder configured to hold the sample, the sample holder disposed adjacent to the image sensor, and an illumination source comprising partially coherent light. The illumination source is configured to illuminate the sample through at least one of an aperture, fiber-optic cable, or optical waveguide interposed between the illumination source and the sample holder, wherein the illumination source is configured to illuminate the sample through a plurality of different angles.

A lens-free system for the three-dimensional imaging of objects contained within a sample places a sample holder between an image sensor and an illumination source, with the sample-sensor distance being much smaller than the sample-illumination source distance. Holographic images are taken at different angles as well as different lateral jogs within a single angle and are reconstructed into a three dimensional image of objects within the sample. The system may be a hand held, portable unit.

The imaging apparatus includes an optical system dividing light into object and reference beams and causing the object beam and the reference beam to interfere with each other to form interference fringes on an image sensor. A processor performs multiple imaging processes for the interference fringes with different incident angles of the object beam to an object, a first process to acquire a transmitted wavefront for each incident angle and a second process to calculate a three-dimensional refractive index distribution from the transmitted wavefronts. The apparatus includes a modulator changing a phase distribution of light in any one of an optical path from a light source to a dividing element, a reference beam path and an optical path from a combining element to the image sensor and causes the modulator to change the phase distribution in at least one of the multiple imaging processes.

A method of generating a hologram of an object is disclosed. The method comprises: receiving data corresponding to a plurality of non-coherent sub-holograms acquired by an optically passive synthetic aperture holographic apparatus, combining the sub-holograms to generate a mosaic hologram of the object, and transmitting the mosaic hologram to a computer readable medium.

Various systems for imaging are provided. An electronic device includes a biometric sensor and a processing system. The biometric sensor includes an illuminator, a mirror, a biometric sensor array and a beam splitter. The beam splitter splits a beam received from the illuminator into a first beam incident on a biometric sensing area and a second beam incident on the mirror. The beam splitter combines the reflected beams from the biometric sensing area and the mirror. Thereafter, the processing system receives data from the sensor array and reconstructs the biometric image.