title: Maskless imaging of dense samples using pixel super-resolution based multi-height lensfree on-chip microscopy.
abstract: Lensfree in-line holographic microscopy offers sub-micron resolution over a large field-of-view (e.g., ~24 mm2) with a cost-effective and compact design suitable for field use. However, it is limited to relatively low-density samples. To mitigate this limitation, we demonstrate an on-chip imaging approach based on pixel super-resolution and phase recovery, which iterates among multiple lensfree intensity measurements, each having a slightly different sample-to-sensor distance. By digitally aligning and registering these lensfree intensity measurements, phase and amplitude images of dense and connected specimens can be iteratively reconstructed over a large field-of-view of ~24 mm2 without the use of any spatial masks. We demonstrate the success of this multi-height in-line holographic approach by imaging dense Papanicolaou smears (i.e., Pap smears) and blood samples.
authors.affiliation: Electrical Engineering Department, University of California, Los Angeles, CA 90095, USA.
authors.forename: Alon
authors.initials: A
authors.lastname: Greenbaum
authors.forename: Aydogan
authors.initials: A
authors.lastname: Ozcan
mesh_terms: D001773:Blood Cells / Q000166:cytology*; D002478:Cells, Cultured; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006696:Holography / Q000295:instrumentation* / Q000379:methods*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000295:instrumentation* / Q000379:methods*; D007909:Lenses; D008853:Microscopy / Q000295:instrumentation*; D014626:Vaginal Smears / Q000379:methods*