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Single-mode fiber coupling efficiency with graded-index rod lenses
Applied Optics, 1994Losses are calculated for the single-mode graded-index- (GRIN-) lens coupler. The main advantage of this coupling system is large separation between fibers with small power loss. The excess loss of the GRIN-lens coupler is due primarily to the misalignments of the GRIN lenses and is most sensitive to angular tilt rather than lateral offset or end ...
R W, Gilsdorf, J C, Palais
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Fiber coupling efficiency for free-space optical communication through atmospheric turbulence
SPIE Proceedings, 2004High-speed free-space optical communication systems have recently used fiber-optic components. The received laser beam in such a system must be coupled into a single-mode fiber at the input of the receiver module. However, propagation through atmospheric turbulence degrades the spatial coherence of a laser beam and limits the fiber-coupling efficiency.
Yamaç, Dikmelik, Frederic M, Davidson
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High efficiency fiber coupling to silicon sandwiched slot waveguides
Optics Communications, 2008Abstract The design of a fiber coupler for high efficiency light coupling to silicon sandwiched slot waveguides is reported. The proposed fiber coupler is based on the inverted taper approach. Parameters have been optimized to maximize coupling efficiency for λ = 1550 nm and TM polarization.
J.V. Galan +4 more
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Fiber coupling efficiency for random light and its applications to lidar
Optics Letters, 1998Employing the van Cittert-Zernike theorem of classical coherence theory, we derive a general expression for the efficiency with which quasi-monochromatic random light can be coupled to an optical fiber by means of a lens. For the important case of a source with Gaussian intensity distribution, we obtain and discuss the dependence of the coupling ...
P J, Winzer, W R, Leeb
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Develop the fiber coupling efficiency based on SPGD control algorithm
9th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Optical Test, Measurement Technology, and Equipment, 2019In the satellite-to-ground laser communication, the beacon light is affected by atmospheric turbulence, atmospheric scattering and atmospheric absorption, so there is a coupling error. And the receiving end of ATP system is affected by random disturbance which lead to the initial coupling place change.
Yao Mao +4 more
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Increased coupling efficiency of fiber coupled modules by smile compensation
High-Power Diode Laser Technology XVII, 2019A technique is experimentally demonstrated which allows for the compensation of the smile of a laser diode bar using a beam transformation system and a telescope array. The beam transformation system consists of a fast-axis collimator and an array of biconvex cylindrical lenses, which rotates each collimated beam by 90°.
Gabriel Pelegrina-Bonilla, Thomas Mitra
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Vertically-bent silicon waveguide for high-efficiency optical fiber coupling
Silicon Photonics: From Fundamental Research to Manufacturing, 2018In silicon photonics, optical coupling between optical fibers and silicon photonics chips still remains a big issue to be improved. Recently we have developed a new surface coupler consisting of a vertically-bent silicon waveguide using ion implantation as a bending method.
Tomoya Yoshida +3 more
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Transverse modes under external feedback and fiber coupling efficiencies of VCSEL's
IEEE Photonics Technology Letters, 1998We report a detailed study on the transverse mode behavior of vertical-cavity surface-emitting lasers (VCSEL's) under strong external feedback. Backreflections from a glass facet result, periodically depending on the feedback phase, in variations of the transverse mode pattern of strongly index guided multitransverse-mode-emitting lasers.
J. Heinrich, H. Zeeb, K.J. Ebeling
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Fiber-coupling efficiency for optical wave propagating through non-Kolmogorov turbulence
Optics Communications, 2014Abstract In the past decades, both the increasing experimental evidences and some results of theoretical investigation on non-Kolmogorov turbulence have been reported. This has prompted the study of optical propagation in non-Kolmogorov atmospheric turbulence.
Liying Tan +4 more
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1.3-μm large spot size laser for efficient fiber coupling
Optical Engineering, 1998Taper and truncation loss calculations, experimental internal reflections, and far-field characteristics and coupling efficiencies into single-mode fiber are reported for a 1.3-?m large spot laser design with laterally tapered active region and a weakly guiding passive waveguide underneath. In the front passive section, the taper is truncated.
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