Abstract
Lens-free holographic on-chip imaging is an emerging approach that offers both wide field-of-view (FOV) and high spatial resolution in a cost-effective and compact design using source shifting based pixel super-resolution. However, color imaging has remained relatively immature for lens-free on-chip imaging, since a 'rainbow' like color artifact appears in reconstructed holographic images. To provide a solution for pixel super-resolved color imaging on a chip, here we introduce and compare the performances of two computational methods based on (1) YUV color space averaging, and (2) Dijkstra's shortest path, both of which eliminate color artifacts in reconstructed images, without compromising the spatial resolution or the wide FOV of lens-free on-chip microscopes. To demonstrate the potential of this lens-free color microscope we imaged stained Papanicolaou (Pap) smears over a wide FOV of ~14 mm(2) with sub-micron spatial resolution.
Highlights
Optical microscopy has been serving engineers, scientists and medical experts for decades
The digital revolution that we have been experiencing over the last decades provides powerful and yet cost-effective resources and components that can be harnessed by computational methods to address some of the shortcomings of conventional microscopy tools [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29]
Lens-free holographic on-chip microscopes that are based on partially coherent illumination form an interesting subgroup of such lens-free imagers [6,39,40,41], in which the distance between sample and the image sensor (Z2, see Fig. 1) is typically less than a millimeter, while the distance between the illumination source and the sample plane (Z1) is relatively large
Summary
Optical microscopy has been serving engineers, scientists and medical experts for decades. The digital revolution that we have been experiencing over the last decades provides powerful and yet cost-effective resources and components that can be harnessed by computational methods to address some of the shortcomings of conventional microscopy tools [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29] Among these emerging computational methods, lens-free imaging has been gaining significant attention since it does not require the use of any lenses or bulky optical components to render an image [6,7,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45]. These in-line holograms can be reconstructed allowing e.g., digital focusing capability or the ability to localize objects with sub-micron tracking accuracy within large volumes [42,43,44]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
