Parabolic reflector

About: Parabolic reflector is a research topic. Over the lifetime, 3375 publications have been published within this topic receiving 30735 citations. The topic is also known as: paraboloid reflector & paraboloidal reflector.

Solar energy collecting system

Abstract: The invention discloses a solar energy collecting system, which comprises a parabolic reflector, a solar panel, a mosaic-shaped photo sensor, a marker post, a sun position calculation module, and a trace driving module. The light receiving surface of the solar panel faces the concave surface of the parabolic reflector, and is vertical to the axes passing the focus of the parabolic reflector and the central point of the concave surface; the sun position calculation module calculates sun position information according to the shadow of the marker post on the mosaic-shaped photo sensor; and the trace driving device drives the parabolic reflector to align the sun according to the sun position information so as to improve the efficiency of collecting solar energy.

Sound pickup assembly

Abstract: A sound pickup assembly comprising a parabolic reflector in the focal point of which is mounted a pickup and wherein the reverse side of the parabolic reflector is formed as a binaural sound pickup having a pair of microphones mounted on opposite sides of the curved surface generally on a horizontal plane and including a pair of dummy external ears mounted near the pair of microphones such that the pickup can be used as a highly directive pickup utilizing the single microphone and parabolic reflector and wherein the unit can also be utilized for binaural pickup by utilizing the two antennas and dummy ears mounted on the back surface of the unit.

Transient Analysis of Scattering From a Perfectly Conducting Parabolic Reflector Illuminated by a Gaussian Beam Electromagnetic Field

Abstract: In this paper we present a time domain (TD) transient analysis of electromagnetic (EM) fields scattered from a perfectly conducting parabolic reflector, when it is illuminated by EM fields of a general astigmatic Gaussian beam (GB). The analysis employs physical optics (PO) approximation and analytic time transform (ATT) to treat complex time delays that result from the GB's complex phase variations along its propagation axis in the frequency domain (FD). This work exhibits two advantages. First, within the validity of the paraxial approximation of the GB fields, this TD-PO quasi-analytic solution is highly efficient in reducing the numerical surface integration into a one-dimensional angular integration, which remains fairly independent of reflector sizes in most practical applications. Second, the nature of the PO approximation assists in avoiding ray-caustic problems encountered in most asymptotic solutions. Numerical examples are presented to illustrate the phenomena of GB scattering, as well as the uses of the described solution.

Dynamic chromatic aberration pre-compensation scheme for ultrashort petawatt laser systems.

Abstract: A novel chromatic aberration pre-compensation scheme for ultrashort petawatt laser systems was proposed. The pre-compensation scheme consists of a convex lens, group of concave lenses, and a spherical reflector combined with a conventional vacuum chamber. It provides a versatile method to accurately compensate the chromatic aberration of an entire laser system via controlling the amount of propagation time delay (PTD) induced by the compensator without changing the input and output beam size. A compensator, tailored based on the proposed scheme, was designed and experimentally evaluated for the Shen-Guang-II 5PW (SG-II 5PW) laser system at Shanghai Institute of Optics and Fine Mechanics (SIOM). The experimental results verified that chromatic aberration in the laser system was almost fully compensated: the size of laser beam focused by an f/2.42 off-axis parabolic mirror (OAP) was reduced tremendously from 32×18μm2to about 4×4μm2at full width at half maximum (FWHM). The proposed scheme provides the flexibility to accurately correct chromatic aberration in high-power laser systems within a wide dynamic range.

Focusing characteristics of a 4 πparabolic mirror light-matter interface

Abstract: Focusing with a 4 π parabolic mirror allows for concentrating light from nearly the complete solid angle, whereas focusing with a single microscope objective limits the angle cone used for focusing to half solid angle at maximum. Increasing the solid angle by using deep parabolic mirrors comes at the cost of adding more complexity to the mirror’s fabrication process and might introduce errors that reduce the focusing quality. To determine these errors, we experimentally examine the focusing properties of a 4 π parabolic mirror that was produced by single-point diamond turning. The properties are characterized with a single 174Yb + ion as a mobile point scatterer. The ion is trapped in a vacuum environment with a movable high optical access Paul trap. We demonstrate an effective focal spot size of 209 nm in lateral and 551 nm in axial direction. Such tight focusing allows us to build an efficient light-matter interface. Our findings agree with numerical simulations incorporating a finite ion temperature and interferometrically measured wavefront aberrations induced by the parabolic mirror. We point at further technological improvements and discuss the general scope of applications of a 4 π parabolic mirror.