Near-field tailored imaging optics for coupling ultra-bright light sources into optical fibers

2005 ◽  
Author(s):  
Doron Nakar ◽  
Daniel Feuermann ◽  
Jeffrey M. Gordon
Keyword(s):  
Optical Fibers ◽  
Near Field ◽  
Bright Light ◽  
Light Sources ◽  
Imaging Optics

Low-Loss Connection of Hybrid Fibre Optic Systems with Low Sensitivity to Wavelength

2013 ◽  
Vol 20 (4) ◽  
pp. 697-704 ◽  
Author(s):  
Krzysztof Skorupski
Keyword(s):  
Optical Fibers ◽  
Near Field ◽  
Signal Transmission ◽  
Single Mode ◽  
Single Mode Fiber ◽  
Light Sources ◽  
Mode Field ◽  
Low Sensitivity ◽  
Comparison Of The Results ◽  
Different Diameters

Abstract This paper proposes a method for adjusting light waves propagating in systems composed of photonic fibers, light sources and detection elements. The paper presents the properties of these connections in terms of the loss of signal transmission. Different fiber core areas were analyzed, and measurements of the mode-field diameters (MFDs) of selected fiber structures are presented. The study analyzed two types of LMA (Large Mode Area) fiber structures, and the mode-field diameters of these structures were measured on the basis of the radiation distribution obtained under near-field conditions. The results are compared to the values obtained for a SMF-28 single-mode fiber. The LMA structures analyzed in the paper are characterized by low sensitivity of the MFD parameter to the length of transmitted waves, which creates the possibility of their use as intermediate fibers when connecting optical fibers of different diameters. In the wavelength range from 800 nm to 1600 nm, a 3.5% MFD change was observed for the first investigated LMA structure, and a 1% change was observed for the second. In addition, measurements of the mode-field diameters were also made using the transverse offset method for comparison of the results.

scholarly journals Imaging with Local Speckle Intensity Correlations: Theory and Practice

2021 ◽  
Vol 40 (3) ◽  
pp. 1-22
Author(s):  
Marina Alterman ◽  
Chen Bar ◽  
Ioannis Gkioulekas ◽  
Anat Levin
Keyword(s):  
Near Field ◽  
Biological Tissues ◽  
Computational Imaging ◽  
Theory And Practice ◽  
Fluorescent Imaging ◽  
Light Sources ◽  
Far Field ◽  
Scattering Layer ◽  
Speckle Patterns ◽  
Field Imaging

Recent advances in computational imaging have significantly expanded our ability to image through scattering layers such as biological tissues by exploiting the auto-correlation properties of captured speckle intensity patterns. However, most experimental demonstrations of this capability focus on the far-field imaging setting, where obscured light sources are very far from the scattering layer. By contrast, medical imaging applications such as fluorescent imaging operate in the near-field imaging setting, where sources are inside the scattering layer. We provide a theoretical and experimental study of the similarities and differences between the two settings, highlighting the increased challenges posed by the near-field setting. We then draw insights from this analysis to develop a new algorithm for imaging through scattering that is tailored to the near-field setting by taking advantage of unique properties of speckle patterns formed under this setting, such as their local support. We present a theoretical analysis of the advantages of our algorithm and perform real experiments in both far-field and near-field configurations, showing an order-of magnitude expansion in both the range and the density of the obscured patterns that can be recovered.

scholarly journals Medical Industry Trends That Promote the Use of Optical Medicine Fiber

2021 ◽  
pp. 76-79
Author(s):  
Dr. R. Thillaikkarasi ◽  
Sindhuja R ◽  
Sivabharati M ◽  
Abira Bright ◽  
Sreejith V
Keyword(s):  
Optical Fibers ◽  
Laser Light ◽  
Light Sources ◽  
Healthcare Industry ◽  
Future Prospects ◽  
Enabling Technology ◽  
Instruments And Techniques ◽  
Ancient Times ◽  
New Generation ◽  
Industry Trends

Optics has, since ancient times, being used as aid for the exam human patients and in some therapeutic treatments. Many of the optic medical instruments in use today were developed in the nineteenth century and, with the advent of optical fibers and laser light sources in the mid twentieth century, a new generation of medical devices, instruments, and techniques have been developed that have helped modernize medicine and perform task unimaginable only a few decades ago. This chapter illustrates through several optical instrument and application examples the uses, benefits, and future prospects that optics brings as an enabling technology to the medicine and the overall healthcare industry.

The Effect of Light on Sleep and Sleep-Related Physiological Factors Among Patients in Healthcare Facilities: A Systematic Review

2019 ◽  
Vol 12 (4) ◽  
pp. 116-141
Author(s):  
Khatereh Hadi ◽  
Jennifer R. Du Bose ◽  
Young-Seon Choi
Keyword(s):  
Light Exposure ◽  
Bright Light ◽  
Light Sources ◽  
Related Factors ◽  
Healthcare Facilities ◽  
New Findings ◽  
Healthcare Environments ◽  
The Impact ◽  
Improve Patient ◽  
Bright Light Exposure

Objectives: Lighting is one of the environmental factors which can improve patient sleep in healthcare environments. Due to the high degree of variation in study designs and results on this topic, the implications have been difficult to interpret. This review consolidates studies on the impact of bright light exposure on sleep to identify lighting conditions that can be applied and researched in future healthcare environments. Methods: We searched for peer-reviewed articles on the impact of light on sleep or sleep-related outcomes in healthcare settings. We provided detailed analysis of the direct links between light and sleep, and a more cursory analysis of links between light and sleep-related factors, from 34 articles which met our inclusion criteria. Results: The current state of the literature includes evidence on how various durations and intensities of morning, midday, and evening bright light exposure, as well as whole-day light exposure interventions can improve specific aspects of sleep. Lighting interventions differed in all attributes (illuminance levels, exposure time, exposure duration, and spectral qualities) but showed promising results in improving patients’ sleep. Conclusions: Short-term bright light exposure in the morning, up to 2 hr of moderate (3,000–10,000 lux) morning exposures, up to 4 hr of moderate evening exposure, and whole-day exposures to lower illuminance levels (<3,000 lux) can improve patient sleep outcomes. Based on new findings on the mechanism through which light impacts sleep, future studies should be more specific about the spectral qualities of light sources.

scholarly journals Ultrafast nonlocal collective dynamics of Kane plasmon-polaritons in a narrow-gap semiconductor

2019 ◽  
Vol 5 (8) ◽  
pp. eaau9956 ◽  
Author(s):  
A. Charnukha ◽  
A. Sternbach ◽  
H. T. Stinson ◽  
R. Schlereth ◽  
C. Brüne ◽  
...  
Keyword(s):  
Fiber Optics ◽  
Near Field ◽  
Three Dimensional ◽  
Large Momentum ◽  
Light Sources ◽  
New States ◽  
High Bandwidth ◽  
And Control ◽  
2D And 3D ◽  
Plasmon Polaritons

The observation of ultrarelativistic fermions in condensed-matter systems has uncovered a cornucopia of novel phenomenology as well as a potential for effective ultrafast light engineering of new states of matter. While the nonequilibrium properties of two- and three-dimensional (2D and 3D) hexagonal crystals have been studied extensively, our understanding of the photoinduced dynamics in 3D single-valley ultrarelativistic materials is, unexpectedly, lacking. Here, we use ultrafast scanning near-field optical spectroscopy to access and control nonequilibrium large-momentum plasmon-polaritons in thin films of a prototypical narrow-bandgap semiconductor Hg0.81Cd0.19Te. We demonstrate that these collective excitations exhibit distinctly nonclassical scaling with electron density characteristic of the ultrarelativistic Kane regime and experience ultrafast initial relaxation followed by a long-lived highly coherent state. Our observation and ultrafast control of Kane plasmon-polaritons in a semiconducting material using light sources in the standard telecommunications fiber-optics window open a new avenue toward high-bandwidth coherent information processing in next-generation plasmonic circuits.

scholarly journals Surface improvement of organic photoresists using a near-field-dependent etching method

2017 ◽  
Vol 8 ◽  
pp. 784-788 ◽  
Author(s):  
Felix J Brandenburg ◽  
Tomohiro Okamoto ◽  
Hiroshi Saito ◽  
Benjamin Leuschel ◽  
Olivier Soppera ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Absorption Edge ◽  
Near Field ◽  
Light Sources ◽  
Etching Technique ◽  
Cross Sectional ◽  
Surface Flattening ◽  
Carrier Scattering ◽  
Atomically Flat ◽  
Scattering Losses

Surface flattening techniques are extremely important for the development of future electrical and/or optical devices because carrier-scattering losses due to surface roughness severely limit the performance of nanoscale devices. To address the problem, we have developed a near-field etching technique that provides selective etching of surface protrusions, resulting in an atomically flat surface. To achieve finer control, we examine the importance of the wavelength of the near-field etching laser. Using light sources at wavelengths of 325 and 405 nm, which are beyond the absorption edge of the photoresist (310 nm), we compare the resulting cross-sectional etching volumes. The volumes were larger when 325 nm light was employed, i.e., closer to the absorption edge. Although 405 nm light did not cause structural change in the photoresist, a higher reduction of the surface roughness was observed as compared to the 325 nm light. These results indicate that even wavelengths above 325 nm can cause surface roughness improvements without notably changing the structure of the photoresist.

Manipulation of infrared dispersive waves in customized microstructured optical fibers for 17 and 20  µm light sources

2020 ◽  
Vol 59 (28) ◽  
pp. 9015
Author(s):  
Surajit Bose ◽  
P. Harshavardhan Reddy ◽  
Jintao Fan ◽  
Ayhan Demircan ◽  
Axel Ruehl ◽  
...  
Keyword(s):  
Optical Fibers ◽  
Light Sources ◽  
Dispersive Waves ◽  
Microstructured Optical Fibers
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