Lens-free tomographic imaging devices and methods

A method of obtaining a three dimensional image of an object contained within a sample comprising:

• illuminating a sample holder configured to hold the sample with an illumination source emitting partially coherent light or coherent light at a first angle, the light passing through at least one of an aperture or a fiber-optic cable prior to illuminating the sample;
• illuminating the sample holder with the illumination source at different angles, the light passing through the aperture or a fiber-optic cable prior to illuminating the sample;
• obtaining, at each angle, a plurality of sub-pixel image frames from an image sensor disposed on an opposing side of the sample holder, wherein the sub-pixel image frames are each obtained by logging at least one of the aperture or fiber-optic cable in a plane substantially parallel to the image sensor;
• digitally converting the sub-pixel image frames at each angle into a single higher resolution hologram for each angle;
• digitally reconstructing projection images for each angle from the higher resolution holograms;
• and
• digitally back projecting three dimensional tomographic images of the object within the sample.

A portable tomographic imager comprising:

• a housing containing a sample holder configured to hold a sample therein;
• a plurality of partially coherent or coherent light sources disposed in the housing at varying angles with respect to a first side of the sample, each of the plurality of light sources being coupled to respective waveguides;
• a microcontroller operatively connected to the plurality of light sources, the microcontroller configured to selectively activate individual light sources;
• an electromagnetic actuator configured to move the waveguides in substantially orthogonal directions;
• and
• an image sensor disposed in the housing on a second opposing side of the sample.