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An optical switch based on an electrowetting prism coupled to a multimode fiber has demonstrated a large extinction ratio with speeds up to 300 Hz. Electrowetting prisms provide a transmissive, low power, and compact alternative to conventional free-space optical switches, with no moving parts. The electrowetting prism performs beam steering of ±3°with an extinction ratio of 47 dB between the ON and OFF states and has been experimentally demonstrated at scanning frequencies of 100–300 Hz. The optical design is modeled in Zemax to account for secondary rays created at each surface interface (without scattering). Simulations predict 50 dB of extinction, in good agreement with experiment.
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On-Chip Si3N4 Spatial Heterodyne Fourier Transform Spectrometer for the Optical Window in Biological Tissue
We designed and demonstrated an on-chip Fourier transform spectrometer on Si3N4-on-SiO2 using an array of Mach-Zehnder interferometers (MZIs) for 𝜆 = 600~1000 nm. The retrieval of an input spectrum is demonstrated by the interconnect simulation.
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- Award ID(s):
- 1932753
- PAR ID:
- 10346768
- Editor(s):
- Optica CLEO program Committee
- Date Published:
- Journal Name:
- Cleo
- ISSN:
- 0928-9062
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Dielectric electroactive polymers are materials capable of mechanically adjusting their volume in response to an electrical stimulus. However, currently these materials require multi-step manufacturing processes which are not additive. This paper presents a novel 3D printed flexible dielectric material and characterizes its use as a dielectric electroactive polymer (DEAP) actuator. The 3D printed material was characterized electrically and mechanically and its functionality as a dielectric electroactive polymer actuator was demonstrated. The flexible 3-D printed material demonstrated a high dielectric constant and ideal stress-strain performance in tensile testing making the 3-D printed material ideal for use as a DEAP actuator. The tensile stress- strain properties were measured on samples printed under three different conditions (three printing angles 0°, 45° and 90°). The results demonstrated the flexible material presents different responses depending on the printing angle. Based on these results, it was possible to determine that the active structure needs low pre-strain to perform a visible contractive displacement when voltage is applied to the electrodes. The actuator produced an area expansion of 5.48% in response to a 4.3 kV applied voltage, with an initial pre-strain of 63.21% applied to the dielectric material.more » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1364/CLEO_AT.2021.JTu3A.122
