Flat lensless phase imager

Lensless imaging refers to an imaging technique which requires no imaging element between the light transmitted by the sample and the camera. This configuration enables designing compact devices. In the visible range, it is mainly investigated for microscopy, because of the high resolution (sub-micrometer) and large field of view (camera chip size) that it provides. Current implementations use illumination sources positioned above the sample several centimeters away making the lensless imager bulky in height. Here we demonstrate an implementation with the illumination sources side illuminating a Dove prism onto which analog holograms are laminated. Diffraction from the analog holograms provides the multiple angle illumination. This results in a flat phase lensless imager.