Inverse Problems in Astronomical Adaptive Optics
... The term adaptive optics (AO) refers to optical systems that adapt in real time to compensate for distorting effects introduced along the propagation path between a light source and a receiver. In ground-based astronomy, light from distant objects is distorted by the effects of turbulence as it prop ...
... The term adaptive optics (AO) refers to optical systems that adapt in real time to compensate for distorting effects introduced along the propagation path between a light source and a receiver. In ground-based astronomy, light from distant objects is distorted by the effects of turbulence as it prop ...
Point spread function engineering in confocal scanning microscopy
... proposed [1]. Confocal scanning microscopes (CSM’s) are imaging systems in which the monochromatic light proceeding from a point source is focused onto a point of a 3D specimen by a high NA objective. Afterwards, the light emitted/reflected by the sample is collected by the same objective, passes th ...
... proposed [1]. Confocal scanning microscopes (CSM’s) are imaging systems in which the monochromatic light proceeding from a point source is focused onto a point of a 3D specimen by a high NA objective. Afterwards, the light emitted/reflected by the sample is collected by the same objective, passes th ...
Optical Fiber Sensors Guide
... wavelengths. However, experimental measurements show much larger index changes. To explain the observed large index changes, Sceats et al. [4] proposed thermoelastic stress relaxation of the glass network caused by formation of regions of low density around broken Ge-Si bonds (stress relief model). ...
... wavelengths. However, experimental measurements show much larger index changes. To explain the observed large index changes, Sceats et al. [4] proposed thermoelastic stress relaxation of the glass network caused by formation of regions of low density around broken Ge-Si bonds (stress relief model). ...
TIE-29: Refractive Index and Dispersion
... Glass for hot processing i.e reheat pressing is subjected to much more rapid annealing. The heat treatment processes used by the customer in general use annealing rates much higher than 2°C/h. Therefore for N-BK7 pressings for example the initial refractive index needs to be higher than the target v ...
... Glass for hot processing i.e reheat pressing is subjected to much more rapid annealing. The heat treatment processes used by the customer in general use annealing rates much higher than 2°C/h. Therefore for N-BK7 pressings for example the initial refractive index needs to be higher than the target v ...
Full text - Simon Fraser University
... Two-dimensional materials, single-layer crystals of atomic thickness, including graphene and boron nitride, have attracted much interest in the last few decades. When electrons are confined to move in two dimensions, several extraordinary applications arise due to this physical effect. For example, th ...
... Two-dimensional materials, single-layer crystals of atomic thickness, including graphene and boron nitride, have attracted much interest in the last few decades. When electrons are confined to move in two dimensions, several extraordinary applications arise due to this physical effect. For example, th ...
Author final version (postprint) - DTU Orbit
... system employing spectral properties of nitric oxides in the ultraviolet range. A good agreement was observed between the results obtained using the two different systems. In the context of the PhD project, it was also important to investigate the spectral properties of major combustion species such ...
... system employing spectral properties of nitric oxides in the ultraviolet range. A good agreement was observed between the results obtained using the two different systems. In the context of the PhD project, it was also important to investigate the spectral properties of major combustion species such ...
Femtosecond Frequency Combs for Optical Clocks and Timing
... Kohl and I worked together on homework and various other (sometimes mischievous, always great fun) projects. Mark Notcutt is responsible for teaching me how to make technical measurements of noise. David Jones gave me the example of building experiments efficiently and expertly. Eric Hudson and espe ...
... Kohl and I worked together on homework and various other (sometimes mischievous, always great fun) projects. Mark Notcutt is responsible for teaching me how to make technical measurements of noise. David Jones gave me the example of building experiments efficiently and expertly. Eric Hudson and espe ...
Visibility study of graphene multilayer structures Guoquan Teo and
... substrates: quartz and NiFe (60 nm) coated Si wafer. The graphite flakes obtained by mechanical exfoliation were transferred to the substrates which include SLG, BLG and FLG sheets. Subsequently, the contrast and Raman spectra were measured to identify SLG and BLG sheets. After that, a thin layer (~ ...
... substrates: quartz and NiFe (60 nm) coated Si wafer. The graphite flakes obtained by mechanical exfoliation were transferred to the substrates which include SLG, BLG and FLG sheets. Subsequently, the contrast and Raman spectra were measured to identify SLG and BLG sheets. After that, a thin layer (~ ...
Waveguide lasers in ytterbium doped tantalum pentoxide for
... waveguide lasers on silicon substrate, as a basis to provide the next generation of mass-producible, low-cost planar devices with many interlocking photonic circuits for multi-functionality. Numerical modelling of symmetrical rib waveguide in Ta2O5 was carried out finding an optimum waveguide design ...
... waveguide lasers on silicon substrate, as a basis to provide the next generation of mass-producible, low-cost planar devices with many interlocking photonic circuits for multi-functionality. Numerical modelling of symmetrical rib waveguide in Ta2O5 was carried out finding an optimum waveguide design ...
An overview of fiber-optic sensors
... 90” as shown in Fig. 15. If two outputs are spaced in this manner, the resulting outputs are in quadrature as shown in Fig. 16. The result is that when one output has optimal sensitivity the other is at its lowest and vice versa. By using both outputs for tracking one can scan through multiple grati ...
... 90” as shown in Fig. 15. If two outputs are spaced in this manner, the resulting outputs are in quadrature as shown in Fig. 16. The result is that when one output has optimal sensitivity the other is at its lowest and vice versa. By using both outputs for tracking one can scan through multiple grati ...
Role of wavefront aberrations of amplified femtosecond pulses in
... 2.6.1 Characterization of a gas jet for laser acceleration in the λ3 regime ............................... 44 2.6.2 Electron acceleration and X ray emission in plasmas ..................................................... 45 2.6.3 Characterization of a gas jet for HHG............................... ...
... 2.6.1 Characterization of a gas jet for laser acceleration in the λ3 regime ............................... 44 2.6.2 Electron acceleration and X ray emission in plasmas ..................................................... 45 2.6.3 Characterization of a gas jet for HHG............................... ...
An introduction to medical imaging with coherent terahertz
... To exploit the spatial and spectral information available, large amounts of data must be collected in the spatial and temporal domains. The volume of data depends on the desired resolutions in the temporal and spatial domains, hardware properties and many accompanying circumstantial factors. Among t ...
... To exploit the spatial and spectral information available, large amounts of data must be collected in the spatial and temporal domains. The volume of data depends on the desired resolutions in the temporal and spatial domains, hardware properties and many accompanying circumstantial factors. Among t ...
DETERMINING SPATIAL MODES OF SEMICONDUCTOR LASERS
... I also appreciate the material support that we received, initially under the direction of John Loehr, from the Air Force Research Laboratory at Wright Patterson Air Force Base. I specifically thank Bill Siskaninetz who fabricated the lasers and packaged them for us, and answered my questions for me. ...
... I also appreciate the material support that we received, initially under the direction of John Loehr, from the Air Force Research Laboratory at Wright Patterson Air Force Base. I specifically thank Bill Siskaninetz who fabricated the lasers and packaged them for us, and answered my questions for me. ...
optical resonances in multilayer structures
... The field of optics usually deals with the behavior of visible, infrared, and ultraviolet light. Results and concepts obtainable for frequency ranges can be transferred to other parts of the spectrum, depending on the available material properties for these frequencies and an technological aspects. ...
... The field of optics usually deals with the behavior of visible, infrared, and ultraviolet light. Results and concepts obtainable for frequency ranges can be transferred to other parts of the spectrum, depending on the available material properties for these frequencies and an technological aspects. ...
The effect of gamma radiation on fibre Bragg
... radiation dosimeter, was proposed. The focus of this study centred on the FBG performance, and in particular the Bragg Wavelength Shift (BWS) whilst being exposed to ionizing radiation. Current research suggests that certain types of fibres manufactured by varying methods produce different results. ...
... radiation dosimeter, was proposed. The focus of this study centred on the FBG performance, and in particular the Bragg Wavelength Shift (BWS) whilst being exposed to ionizing radiation. Current research suggests that certain types of fibres manufactured by varying methods produce different results. ...
Theoretical modeling and evaluation of the axial resolution of the
... that will result in the highest achievable axial resolution for any imaging system.2 The axial intensity response curves calculated for a typical subject imaged with and without AO using a 23- and an 80-m pinhole are shown in Fig. 2. The initial r.m.s. without AO is 0.60 m and the mean r.m.s. afte ...
... that will result in the highest achievable axial resolution for any imaging system.2 The axial intensity response curves calculated for a typical subject imaged with and without AO using a 23- and an 80-m pinhole are shown in Fig. 2. The initial r.m.s. without AO is 0.60 m and the mean r.m.s. afte ...
Analysis And Design Of Wide-angle Foveated Optical
... using liquid crystal (LC) spatial light modulators (SLM) has received considerable attention as a potential approach to reducing size and complexity in fast wide-angle lenses. The fundamental concept behind optical foveated imaging is reducing the number of elements in a fast wide-angle lens by plac ...
... using liquid crystal (LC) spatial light modulators (SLM) has received considerable attention as a potential approach to reducing size and complexity in fast wide-angle lenses. The fundamental concept behind optical foveated imaging is reducing the number of elements in a fast wide-angle lens by plac ...
Wave optical simulations of x-ray nano
... sources, but confine to “classical”, noisy sources. It can be expected that correlations between these emitters can be incorporated using correlated random coefficients. Since the phase-relations are subject to rapid and random changes on a time-scale of the coherence time τc , interference effects ...
... sources, but confine to “classical”, noisy sources. It can be expected that correlations between these emitters can be incorporated using correlated random coefficients. Since the phase-relations are subject to rapid and random changes on a time-scale of the coherence time τc , interference effects ...
Chapter 4 Optical Resonator
... cleaved along crystal planes. These surfaces act as reflectors and therefore serve as the resonator mirrors. Consider a crystal with refractive index n = 3.6 placed in air (n = 1). The light reflects between two parallel surfaces separated by the distance d = 0.2 mm. Determine the spacing between re ...
... cleaved along crystal planes. These surfaces act as reflectors and therefore serve as the resonator mirrors. Consider a crystal with refractive index n = 3.6 placed in air (n = 1). The light reflects between two parallel surfaces separated by the distance d = 0.2 mm. Determine the spacing between re ...
sensors Chemical Sensing Using Fiber Cavity Ring-Down Spectroscopy
... refractive index measurements was developed by our group and others since 2002. In fiber-cavity ring-down spectroscopy the optical cavity consists of a strand of single-mode or multi-mode fiber optic cable. The light is trapped in the cavity by either using “mirrors” (i.e., reflective coatings [16] ...
... refractive index measurements was developed by our group and others since 2002. In fiber-cavity ring-down spectroscopy the optical cavity consists of a strand of single-mode or multi-mode fiber optic cable. The light is trapped in the cavity by either using “mirrors” (i.e., reflective coatings [16] ...
Chapter 4 Optical Resonator
... cleaved along crystal planes. These surfaces act as reflectors and therefore serve as the resonator mirrors. Consider a crystal with refractive index n = 3.6 placed in air (n = 1). The light reflects between two parallel surfaces separated by the distance d = 0.2 mm. Determine the spacing between re ...
... cleaved along crystal planes. These surfaces act as reflectors and therefore serve as the resonator mirrors. Consider a crystal with refractive index n = 3.6 placed in air (n = 1). The light reflects between two parallel surfaces separated by the distance d = 0.2 mm. Determine the spacing between re ...
Waveinduced light field fluctuations in measured irradiance depth
... In this study, an effort is particularly devoted to quantifying the magnitude and frequency structure of the irradiance fluctuations as a function of water depth under clear skies. Different than previous studies, the irradiance depth profiles measured by a free-fall radiometer in the upper ocean wate ...
... In this study, an effort is particularly devoted to quantifying the magnitude and frequency structure of the irradiance fluctuations as a function of water depth under clear skies. Different than previous studies, the irradiance depth profiles measured by a free-fall radiometer in the upper ocean wate ...
Multiterawatt few-cycle pulse OPCPA
... The field of laser physics has seen tremendous growth since the first practical realization of laser light in 1960 [1]. The first laser pulses were produced by gain switching and by Q-switching also known as giant pulse formation. In the following years lasing action was reported from a HeNe gas mixtur ...
... The field of laser physics has seen tremendous growth since the first practical realization of laser light in 1960 [1]. The first laser pulses were produced by gain switching and by Q-switching also known as giant pulse formation. In the following years lasing action was reported from a HeNe gas mixtur ...
3D optical data storage
3D optical data storage is the term given to any form of optical data storage in which information can be recorded and/or read with three-dimensional resolution (as opposed to the two-dimensional resolution afforded, for example, by CD).This innovation has the potential to provide petabyte-level mass storage on DVD-sized discs (120mm). Data recording and readback are achieved by focusing lasers within the medium. However, because of the volumetric nature of the data structure, the laser light must travel through other data points before it reaches the point where reading or recording is desired. Therefore, some kind of nonlinearity is required to ensure that these other data points do not interfere with the addressing of the desired point.No commercial product based on 3D optical data storage has yet arrived on the mass market, although several companies are actively developing the technology and claim that it may become available ""soon"".