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- Complex epsilon-plane, optical-constants, contours (1)
- Multidimensional constellation, constant envelope, quadrature-quadrature phase shift keying, constellation expansion, trellis coded modulation. (1)
- Optical-constants (1)
- Polarizations, substrate, device, film (1)
- Pseudo-brewster angle, optical-constants (1)
Articles 1 - 8 of 8
Full-Text Articles in Engineering
Plurality Of Principal Angles For A Given Pseudo-Brewster Angle When Polarized Light Is Reflected At A Dielectric-Conductor Interface, R. M.A. Azzam, A. Alsamman
Plurality Of Principal Angles For A Given Pseudo-Brewster Angle When Polarized Light Is Reflected At A Dielectric-Conductor Interface, R. M.A. Azzam, A. Alsamman
Electrical Engineering Faculty Publications
The pseudo-Brewster angle ϕpB of minimum reflectance for p-polarized light and the principal angle ϕ¯ at which incident linearly polarized light of the proper azimuth is reflected circularly polarized are considered as functions of the complex relative dielectric function ε of a dielectric–conductor interface over the entire complex ε plane. In particular, the spread of ϕ¯for a given ϕpB is determined, and the maximum difference (ϕ¯−ϕpB)max is obtained as a function of ϕpB . The maximum difference (ϕ¯−ϕpB)max approaches 45° and 0 in the limit as ϕpB→0 and 90°, respectively. ForϕpB<22.666° , multiple principal angles ϕ¯i , i=1,2,3 , appear for each ε in a subdomain of fractional optical constants. …
In-Line Broadband 270 Degrees (3 Lambda/4) Chevron Four-Reflection Wave Retarders, R. M.A. Azzam, H. K. Khanfar
In-Line Broadband 270 Degrees (3 Lambda/4) Chevron Four-Reflection Wave Retarders, R. M.A. Azzam, H. K. Khanfar
Electrical Engineering Faculty Publications
The net differential phase shift Δt introduced between the orthogonal p and s linear polarizations after four successive total internal reflections inside an in-line chevron dual-Fresnel-rhomb retarder is a function of the first internal angle of incidence φ and prism refractive index n. Retardance of 3λ/4 (i.e., Δt=270°) is achieved with minimum angular sensitivity when φ=45° and n=1.900822. Several optical glasses with this refractive index are identified. For Schott glass SF66 the deviation of Δt from 270° is ≤4° over a wavelength range of 0.55≤λ≤1.1 μm in the visible and …
Quasi Index Matching For Minimum Reflectance At A Dielectric-Conductor Interface For Obliquely Incident P- And S-Polarized Light, R. M.A. Azzam, A. Alsamman
Quasi Index Matching For Minimum Reflectance At A Dielectric-Conductor Interface For Obliquely Incident P- And S-Polarized Light, R. M.A. Azzam, A. Alsamman
Electrical Engineering Faculty Publications
Conditions for reducing the reflectance of a dielectric-conductor interface for p- and s-polarized light to a minimum at any angle of incidence ϕ are determined. The refractive indices of a transparent immersion medium (liquid) that achieve minimum reflectance at normal incidence, ϕ=0, and at ϕ=45° are independent of polarization. These indices provide sufficient data to determine the real and imaginary parts of the complex refractive index of an absorbing substrate. Reflection at a dielectric-Au interface at 500 nm wavelength is considered as an example. It is shown that the lowest possible reflectance is attained for p …
Reflection Coefficients Of P- And S-Polarized Light By A Quarter-Wave Layer: Explicit Expressions And Application To Beam Splitters, R. M.A. Azzam, F. F. Sudradjat
Reflection Coefficients Of P- And S-Polarized Light By A Quarter-Wave Layer: Explicit Expressions And Application To Beam Splitters, R. M.A. Azzam, F. F. Sudradjat
Electrical Engineering Faculty Publications
The complex-amplitude reflection coefficients of p- and s-polarized light by a transparent freestanding, embedded, or deposited quarter-wave layer (QWL) are derived as explicit functions of the angle of incidence and layer refractive index. This provides the basis for the design of 50%-50% beam splitters for incident s-polarized or unpolarized light that use a high-index (e.g., TiO2 or Ge) QWL embedded in a glass cube in the visible and near infrared spectral range. These simple devices have good angular and spectral response and are insensitive to small film thickness errors to the first order.
Efficiency Of Linear-To-Circular Polarization Conversion For Light Reflection At The Principal Angle By A Dielectric-Conductor Interface, R. M.A. Azzam, A. Alsamman
Efficiency Of Linear-To-Circular Polarization Conversion For Light Reflection At The Principal Angle By A Dielectric-Conductor Interface, R. M.A. Azzam, A. Alsamman
Electrical Engineering Faculty Publications
The efficiency ηLC of linear-to-circular polarization conversion when light is reflected at a dielectric–conductor interface is determined as a function of the principal angle ϕ¯ and principal azimuth ψ¯ . Constant- ηLC contours are presented in the ϕ¯ ,ψ¯ plane for values of ηLC from 0.5 to 1.0 in steps of 0.05, and the corresponding contours in the complex plane of the relative dielectric function ϵ are also determined. As specific examples, efficiencies ⩾88% are obtained for light reflection by a Ag mirror in the visible and near-IR (400–1200nm) spectral range, and ≥40% for the reflection of extreme ultraviolet (EUV) …
Polarization Properties Of Retroreflecting Right-Angle Prisms, R. M.A. Azzam, H. K. Khanfar
Polarization Properties Of Retroreflecting Right-Angle Prisms, R. M.A. Azzam, H. K. Khanfar
Electrical Engineering Faculty Publications
The cumulative retardance Δt introduced between the p and the s orthogonal linear polarizations after two successive total internal reflections (TIRs) inside a right-angle prism at complementary angles Φ and 90°−Φ is calculated as a function of Φ and prism refractive index n. Quarter-wave retardation (QWR) is obtained on retroreflection with minimum angular sensitivity when n=(√2+1)1/2=1.55377 and Φ=45°. A QWR prism made of N-BAK4 Schott glass (n=1.55377 at λ=1303.5 nm) has good spectral response (<5° retardance error) over the 0.5-2 μm visible and near-IR spectral range. A ZnS-coated right-angle Si prism achieves QWR with an error of <±2.5° in the 9-11 μm (CO2 laser) IR spectral range. This device functions as a linear-to-circular polarization transformer and can be tuned to exact QWR at any …
A Novel Expanded 16-Dimensional Constant Envelope Q2psk Constellation, Milton I. Quinteros, Kenneth V. Cartwright, Edit J. Kaminsky, Ricardo U. Gallegos
A Novel Expanded 16-Dimensional Constant Envelope Q2psk Constellation, Milton I. Quinteros, Kenneth V. Cartwright, Edit J. Kaminsky, Ricardo U. Gallegos
Electrical Engineering Faculty Publications
We introduce a 16-dimensional constant-amplitude constellation that is generated by concatenating either four constant envelope quadrature-quadrature phase shift keying (CEQ2PSK) symbols from Saha and Birdsall or four CEQ2PSK symbols recently discovered by Cartwright and also introduced here. Our new constellation doubles the number of points available for data transmission without decreasing the distance between points or increasing energy, and may therefore be used in a trellis coded modulation (TCM) system without constellation expansion penalty. Because the new constellation has constant envelope, the modulation scheme becomes very attractive for nonlinear channels such as the magnetic recording channel or the satellite channel …
Classification Of Cylindrical Targets Buried In Seafloor Sediments, Edit J. Kaminsky, Madalina Barbu
Classification Of Cylindrical Targets Buried In Seafloor Sediments, Edit J. Kaminsky, Madalina Barbu
Electrical Engineering Faculty Publications
This paper presents the development and evaluation of a time-frequency processing technique for detection and classification of buried cylindrical targets from chirpbased parametric sonar data. The software is designed to discriminate between cylindrical targets —such as cables— of different diameters, which need to be identified as different from other strong reflectors or point targets. The method is evaluated on synthetic data generated with an acoustic scattering model for elastic cylinders for seven different diameters. The model generates characteristic responses of targets acquired by a parametric sonar system. The signal at the sonar receiver hydrophones is first windowed to reduce the …