Topic
Diffraction grating
About: Diffraction grating is a research topic. Over the lifetime, 24884 publications have been published within this topic receiving 372437 citations. The topic is also known as: grating.
Papers published on a yearly basis
Papers
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TL;DR: In this paper, the authors presented the first measured data on a Bragg reflection grating based fiber-optic prism true time delay processor for transmit/receive phased array beamforming, which takes maximum advantage of component reuse and fully integrates the transmit and receive modes in one efficient hardware compressive topology.
Abstract: This letter presents, for the first time, measured data on a Bragg reflection grating based fiber-optic prism true time delay processor for transmit/receive phased array beamforming. Measurements taken over a 3.5-GHz bandwidth demonstrates high resolution beamsteering and highly linear low-noise phase data. The system takes maximum advantage of component reuse and fully integrates the transmit and receive modes in one efficient hardware compressive topology.
195 citations
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TL;DR: In this paper, both straight and curved waveguides are written in a variety of silicate glasses using near-IR femtosecond laser pulses, and the laser pulse-induced refractive index change is reconstructed from near-field mode profile data using the scalar wave equation and by refractive near field profiling.
Abstract: Both straight and curved waveguides are written in a variety of silicate glasses using near-IR femtosecond laser pulses. Writing parameters are identified that produce waveguides that support only a single mode and yield smooth-mode profiles. The laser pulse-induced refractive index change is reconstructed from near-field mode profile data using the scalar wave equation and by refractive near-field profiling. Waveguide propagation losses are determined by throughput and Fabry-Perot resonator measurements. Both coarse and fine period gratings are written and characterized, and the thermal stability of these gratings is investigated. The utility of the femtosecond writing technique is demonstrated by fabricating an optical interleaver.
195 citations
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TL;DR: In this article, the authors describe the rigorous vector theories of diffraction gratings, which are able to solve almost all the classical problems of gratings encountered by manufacturers and users.
Abstract: Publisher Summary This chapter describes the rigorous vector theories of diffraction gratings. The diffraction grating is a valuable instrument for scientific research. It is mainly used for spectroscopy and filtering. Even though the holographic grating has not eliminated the classical, ruled grating, which remains the most suitable for important applications, it has permitted a considerable extension of the use of gratings for industrial or scientific purposes such as wavelength selectors for tunable lasers, selective surfaces for solar energy, masks for photolithography, beam sampling mirrors for high power lasers, spectrometers in extreme ultraviolet (UV) or x-ray regions for Space Optics. In addition, one can consider that rigorous vector theories of gratings are able to solve almost all the classical problems of gratings encountered by manufacturers and users.
194 citations
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02 May 2008
TL;DR: In this article, a sample placed under a microscope is illuminated by light from a laser beam, which is passed back via a dichroic filter to various optical components which analyse the Raman spectrum, and thence to a CCD detector.
Abstract: A sample placed under a microscope is illuminated by light from a laser beam. Raman scattered light is passed back via a dichroic filter to various optical components which analyse the Raman spectrum, and thence to a CCD detector. The optical components for analysing the Raman spectrum include tunable dielectric filters in a filter wheel; a Fabry-Perot etalon; and a diffraction grating. These various components may be swapped into the optical path as desired, for example using movable mirrors, enabling the apparatus to be used very flexibly for a variety of different analysis procedures. Various novel analysis methods are also described.
194 citations
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TL;DR: In this paper, the thermal decay of fiber bragg gratings with and without hydrogen loading was examined over a period in excess of 5000 h and it was shown that the non-hydrogen loaded gratings do not obey the power law model.
Abstract: Fiber Bragg gratings (FBGs) have been written in silica fiber codoped with boron and germanium, using a continuous-wave (CW) 244-nm laser. The thermal decay of the gratings written with and without hydrogen loading is examined over a period in excess of 5000 h. It is shown that the thermal decay of the nonhydrogen loaded gratings is well explained by the power law model proposed by Erdogan. Gratings written in hydrogen loaded fiber, however, do not obey the power law model. A new model is presented based on a log time representation which can be used to predict the decay characteristics of gratings written in hydrogen loaded fiber.
192 citations