Off-axis illumination direct-to-digital holography

An apparatus operable to digitally record an off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis, comprising:

• a laser;
• a beamsplitter optically coupled to the laser;
• a reference beam mirror optically coupled to the beamsplitter;
• a focusing lens optically coupled to the reference beam mirror;
• a digital recorder optically coupled to the focusing lens;
• and
• a computer that performs a Fourier transform, applies a digital filter, and performs an inverse Fourier transform,
• wherein a reference beam is incident upon the reference beam mirror at a non-normal angle, an object beam is incident upon an object at an angle with respect to an optical axis defined by the focusing lens, the reference beam and the object beam are focused by the focusing lens at a focal plane of the digital recorder to form the off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes for Fourier analysis which is recorded by the digital recorder, and the computer transforms axes of the recorded off-axis illuminated spatially heterodyne hologram including spatially heterodyne fringes in Fourier space to sit on top of a heterodyne carrier frequency defined by an angle between the reference beam and the object beam and cuts off signals around an original origin before performing the inverse Fourier transform.