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Holographic displays promise to deliver unprecedented display capabilities in augmented reality applications, featuring a wide field of view, wide color gamut, spatial resolution, and depth cues all in a compact form factor. While emerging holographic display approaches have been successful in achieving large étendue and high image quality as seen by a camera, the large étendue also reveals a problem that makes existing displays impractical: the sampling of the holographic field by the eye pupil. Existing methods have not investigated this issue due to the lack of displays with large enough étendue, and, as such, they suffer from severe artifacts with varying eye pupil size and location. We show that the holographic field as sampled by the eye pupil is highly varying for existing display setups, and we propose pupil-aware holography that maximizes the perceptual image quality irrespective of the size, location, and orientation of the eye pupil in a near-eye holographic display. We validate the proposed approach both in simulations and on a prototype holographic display and show that our method eliminates severe artifacts and significantly outperforms existing approaches.
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Holographic Molecular Binding Assays
Holographic particle characterization yields the diameter of individual colloidal spheres with nanometer precision and can resolve probe beads growing as molecules bind to their surfaces. We demonstrate label-free holographic assays for antibodies and for antigenic proteins from pathogenic viruses, including SARS-CoV-2 and H1N1.
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- Award ID(s):
- 2104837
- PAR ID:
- 10511617
- Publisher / Repository:
- Optica Publishing Group
- Date Published:
- Journal Name:
- Digital Holography and 3-D Imaging 2022
- ISBN:
- 978-1-957171-12-8
- Page Range / eLocation ID:
- M2A.6
- Format(s):
- Medium: X
- Location:
- Cambridge
- Sponsoring Org:
- National Science Foundation
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Holographic particle characterization treats holographic microscopy of colloidal particles as an inverse problem whose solution yields the diameter, refractive index and three-dimensional position of each particle in the field of view, all with exquisite precision. This rich source of information on the composition and dynamics of colloidal dispersions has created new opportunities for fundamental research in soft-matter physics, statistical physics and physical chemistry, and has been adopted for product development, quality assurance and process control in industrial applications. Aberrations introduced by real-world imaging conditions, however, can degrade performance by causing systematic and correlated errors in the estimated parameters. We identify a previously overlooked source of spherical aberration as a significant source of these errors. Modeling aberration-induced distortions with an operator-based formalism identifies a spatially varying phase factor that approximately compensates for spherical aberration in recorded holograms. Measurements on model colloidal dispersions demonstrate that phase-only aberration compensation greatly improves the accuracy of holographic particle characterization without significantly affecting measurement speed for high-throughput applications.more » « less
- Free Publicly Accessible Full Text
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Accepted Manuscript
- Conference Paper:
- https://doi.org/10.1364/DH.2022.M2A.6
