Zobrazeno 1 - 10
of 28
pro vyhledávání: '"Chulwoo Oh"'
Autor:
Michael J. Escuti, Chulwoo Oh
Publikováno v:
SID Symposium Digest of Technical Papers. 38:1401-1404
We propose and experimentally demonstrate an achromatic polarization grating, with ~100% diffraction efficiency over nearly the entire visible spectral range. This five-fold enhancement (~34.3% versus ~6.8%) is produced by two chiral liquid crystal l
Publikováno v:
IEEE Photonics Technology Letters. 22:200-202
A new beam steering concept comprising independently rotating, inline polarization gratings (PGs) is experimentally demonstrated. The approach, which we term Risley gratings, achieves high steering throughput within a large field-of-regard (FOR) in a
Autor:
Jihwan Kim, Matthew N. Miskiewicz, Michael W. Kudenov, Chulwoo Oh, Yanming Li, Michael J. Escuti
Publikováno v:
Optica. 2:958
Throughout optics and photonics, phase is normally controlled via an optical path difference. Although much less common, an alternative means for phase control exists: a geometric phase (GP) shift occurring when a light wave is transformed through on
Publikováno v:
Applied optics. 50(17)
We introduce and demonstrate a ternary nonmechanical beam steering device based on polarization gratings (PGs). Our beam steering device employs multiple stages consisting of combinations of PGs and wave plates, which allows for a unique three-way (t
Publikováno v:
Optics express, vol 18, iss 5
Optics Express
Optics Express
We introduce the use of a birefringent crystal with lensless digital holography to create an on-chip differential interference contrast (DIC) microscope. Using an incoherent source with a large aperture, in-line holograms of micro-objects are created
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b881d085d69109885a633c3aea6f0b59
https://escholarship.org/uc/item/714175q0
https://escholarship.org/uc/item/714175q0
Publikováno v:
Conference on Lasers and Electro-Optics 2010.
We demonstrate an on-chip polarization microscope based on incoherent lensfree holography. Placed between two polarizers, a birefringent sample creates in-line holograms that can be digitally reconstructed to create lensfree polarization images over
Publikováno v:
SPIE Proceedings.
We introduce a new beam steering concept of the Risley grating that consists of independently rotating inlinepolarizationgratings(PGs). TheRisleygratingconceptreplacesthebulkyprismaticelementsoftheRisleyprismswith thin plates containing polarizat
Publikováno v:
SPIE Proceedings.
We report our experimental success in realizing high efficiency liquid crystal polarization gratings (LCPGs) on reflective substrates, with periods as small as 2.2μm, enabling the largest switchable LCPG diffraction angles reported yet for red light
Autor:
Michael J. Escuti, Chulwoo Oh
Publikováno v:
SPIE Proceedings.
We have experimentally demonstrated broadband light modulation by achromatic liquid crystal (LC) polarization gratings (PGs), which manifest polarization-independent modulation with high efficiencies (≥ 95%). Recently, we introduced achromatic PGs
Publikováno v:
SPIE Proceedings.
We introduce and demonstrate a compact, nonmechanical beam steering device based on liquid Crystal (LC) Polarization Gratings (PGs). Directional control of collimated light is essential for free-space optical communications, remote sensing, and relat