Visible and near infrared, wide-angle, anti-reflection coatings with self-cleaning on glass

AbstractDeflection, a basic functionality of wavefront manipulation is usually associated with the phase-gradient metasurfaces and the classical blazed gratings. We numerically and experimentally demonstrate an unusually wideband and simultaneously wide-angle deflection achieved at near-infrared in reflection mode for a periodic (nongradient), ultrathin meta-array comprising only one silicon nanorod (Mie resonator) per period. It occurs in the range where only the first negative diffraction order and zero order may propagate. Deflection serves as the enabler for multifunctional operation. Being designed with the main goal to obtain ultra-wideband and wide-angle deflection, the proposed meta-array is also capable in spatial filtering and wide-angle splitting. Spatial filtering of various types can be obtained in one structure by exploiting either deflection in nonzero diffraction orders, or the specular-reflection (zero-order) regime. Thus, the role of different diffraction orders is clarified. Moreover, on–off switching of deflection and related functionalities is possible by changing polarization state of the incident wave. The suggested device is simple to fabricate and only requires cost-effective materials, so it is particularly appropriate for the large-area fabrication using nanoprint lithography. Ultra-wideband wide-angle and other deflection scenarios, along with the other functionalities, are promising for applications in optical communications, laser optics, sensing, detection, and imaging.

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Application of wide-field infrared reflectance imaging in retinoschisis, retinal detachments, and schisis detachments

International Journal of Retina and Vitreous ◽

10.1186/s40942-019-0188-5 ◽

2019 ◽

Vol 5 (S1) ◽

Author(s):

Himanshu K. Banda ◽

Anjali Shah ◽

Gaurav K. Shah

Keyword(s):

Retinal Detachment ◽

Near Infrared ◽

Infrared Imaging ◽

Anterior Segment ◽

Infrared Light ◽

Main Body ◽

Wide Field ◽

Wide Angle ◽

Infrared Reflectance ◽

Non Invasive

Abstract Background Retinoschisis and retinal detachment are distinguished based on features in clinical examination. Even to skilled examiners, some cases may be diagnostic challenges. Infrared and wide-angle infrared reflectance imaging are relatively new modalities that can provide additional diagnostic information. Non-contact infrared reflectance imaging (also described as near-infrared imaging) highlights sub-retinal features which may otherwise be obscured by standard retinal photography. It is non-invasive and uses the retina’s ability to absorb, reflect or scatter infrared light to produce high quality images. Main body The aim of this review is to describe the role of wide-field infrared imaging in screening, diagnosing, and monitoring structural peripheral retinal disorders including retinoschisis, retinal detachment or combined retinoschisis rhegmatogenous detachments. Infrared imaging can also be used to monitor anterior segment inflammation. Heidelberg Wide-Field Module lens and Heidelberg Spectralis® HRA + OCT machine (Heidelberg Engineering, Heidelberg, Germany) were used to obtain noncontact, wide-field infrared images on each study eye. Pseudocolor photos were captured by Optos Optomap® (Optos, Inc, Massachusetts, USA). Conclusion Wide angle infrared imaging offers a quick, noncontact, and noninvasive way to help specialists accurately diagnose, monitor for progression, and educate patients about retinal detachment, retinoschisis and even anterior segment inflammation.

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