This paper presents a novel approach to synthesizing curved reflectarrays using Geometrical Optics (GO). It introduces the concepts of virtual normal and path length shift, which enable vector-based formulation problem that can be solved ray tracing techniques. The is applied for design two different versions Dual Bifocal Reflectarray with parabolic main surface flat subreflectarray. first vers...

We study low-temperature properties of the XY spin model on a negatively curved surface. Geometric curvature of the surface gives rise to frustration in local spin configuration, which results in the formation of high-energy spin clusters scattered over the system. Asymptotic behavior of the spin-glass susceptibility suggests a zero-temperature glass transition, which is attributed to multiple ...

We demonstrate the lithographic fabrication of diffractive optical elements (DOEs) in hybrid SiO2/TiO2 sol-gel glass on 3-D curved surfaces. The concentric circular gratings with periods of 20 μm, 10 μm and 5 μm have been fabricated in sol-gel glass on concave lens by laser direct writing successfully. Continuous 3-Dimensional surface relief with a height of 435 nm, 110 nm and 50 nm has been ob...

Analogous coherent states are deduced from classical optical fields on curved surface in this paper. The Gaussian laser beam, as a fundamental mode, cannot be adequately simulated by due to their inherent diffraction flat space. But things will different when it propagates with uniform curvature called the constant (CGCS). By generalizing method of Feynman path integral, an equivalent solution ...

Computing the visible portions of curved surfaces from a given viewpoint is of great interest in many applications It is closely related to the hidden surface removal problem in computer graphics and machining applications in manufacturing Most of the earlier work has focused on discrete methods based on polygonization or ray tracing and hidden curve removal In this paper we present an algorith...

The macaque anterior intraparietal area (AIP) is crucial for visually guided grasping. AIP neurons respond during the visual presentation of real-world objects and encode the depth profile of disparity-defined curved surfaces. We investigated the neural representation of curved surfaces in AIP using a stimulus-reduction approach. The stimuli consisted of three-dimensional (3-D) shapes curved al...

This paper presents algorithms for optimal development (flattening) of a smooth continuous curved surface embedded in three-dimensional space into a planar shape. The development process is modeled by in-plane strain (stretching) from the curved surface to its planar development. The distribution of the appropriate minimum strain field is obtained by solving a constrained nonlinear programming ...

Through the method of analyzing the intrinsic relationship of the nodal point series of the path on curved surface, circle arc approach method is put forward corresponding to the shortest path to solve the curved surface problem by local tuning. Particle swarm optimization has made faster development due to its easy understanding and implement. Particle swarm algorithm has strong local search a...

In three experiments, observers judged the apparent extents of spatial intervals along the surface of a curved cylinder or a flat plane that was binocularly viewed in a natural, indoor environment. The observers' judgments of surface lengths were precise and reliable but were also inaccurate and subject to relatively large constant errors. These distortions differed among the observers, but the...