Vision impairment caused by degenerative retinal pathologies such as age-related macular degeneration can be treated using retinal implants. Such devices receive power and data using cables passing through a permanent surgical incision in the eye wall (sclera), which increases the risk to patients and surgical costs. A recently developed retinal implant design eliminates the necessity of the implant cable using a photonic power converter (PPC), which receives optical power and data through the pupil and is directed by an ellipsoidal reflector and micro-electromechanical mirror. We present a misalignment compensation algorithm model that accounts for rigid-body motions of the reflector relative to the eye and applies the correction to the mirror coordinates in the presence of angular misalignment of the reflector. We demonstrate that up to 85% of the nominal optical power can be delivered to the implant with axial reflector misalignments up to 30 deg using the compensation algorithm.
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http://dx.doi.org/10.1115/1.4050026 | DOI Listing |
Sensors (Basel)
December 2024
Qualcomm Communication Technologies (Shanghai) Co., Ltd., Shanghai 201208, China.
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December 2024
School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore.
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November 2024
Applied Physics Department, Engineering Research Institute of Aragon (I3A), Faculty of Science, University of Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza, Spain.
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November 2024
Key Laboratory of Architectural Cold Climate Energy Management, Ministry of Education, Jilin Jianzhu University, Changchun 130118, China.
The electrical, stability and optoelectronic properties of GZTO TFTs with different Ga doping concentrations were investigated. Active layers were prepared by co-sputtering GaO and ZTO targets with different sputtering powers. The experimental results show that the surface of GZTO films is smooth, which is favorable for stability.
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Department of Material Science and Engineering, University of Ioannina, 45110 Ioannina, Greece.
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