Total external reflection

About: Total external reflection is a research topic. Over the lifetime, 829 publications have been published within this topic receiving 22213 citations.

Electrolytic‐Tank Measurements for Microwave Metallic Delay‐Lens Media

Abstract: In this paper it is shown how the low frequency index of refraction of a metallic delay‐lens medium may be calculated from electrolytic‐tank measurements on individual metallic elements of the medium. The proximity between adjacent elements is taken exactly into account for low frequencies. The test apparatus is described, and measured results are presented for three kinds of delay‐lens structures.

Comparison between experimental and theoretical rocking curves in extremely asymmetric Bragg cases of X-ray diffraction

Abstract: Double-crystal rocking Curves from a highly perfect silicon crystal were taken in extremely asymmetric schemes, in which the glancing angles of the incident X-rays were very close to the critical angle of total external reflection. The experimental rocking curves were compared with theoretical calculations based both on an ordinary dynamical theory of diffraction and also on an extended dynamical theory, which uses a more exact solution of the fundamental equation of the dynamical theory and takes the effect of specular reflection into account. It is demonstrated from such a comparison that, in the case of extremely asymmetric diffraction, the ordinary treatment of the dynamical theory of diffraction is not valid; in contrast, the extended theory explains the rocking curve very well.

X-ray nanoscale profiling of layer-by-layer assembled metal/organophosphonate films.

Abstract: The nanoscale structure of multilayer metal/phosphonate thin films prepared via a layer-by-layer assembly process was studied using specular X-ray reflectivity (XRR), X-ray fluorescence (XRF), and long-period X-ray standing wave (XSW) analysis. After the SiO2 X-ray mirror surfaces were functionalized with a monolayer film terminated with phosphonate groups, the organic multilayer films were assembled by alternating immersions in (a) aqueous solutions containing Zr4+, Hf4+, or Y3+ cations and then (b) organic solvent solutions of PO3−R−PO3, where R was a porphyrin or porphyrin-square spacer molecule. The different heavy metal cations provided X-ray fluorescence marker layers at different heights within the different multilayer assemblies. The XSW measurements used a 22 nm period Si/Mo multilayer mirror. The long-period XSW generated by the zeroth-order (total external reflection) through fourth-order Bragg diffraction conditions made it possible to examine the Fourier transforms of the fluorescent atom dis...

Multi-purpose sensor system and sensing method using internally reflected light beams

Abstract: A sensor system including a first layer having first and second surfaces and a first index of refraction, a second layer having a second index of refraction which is less than the first index of refraction, a mechanism for generating a first diffuse light beam which passes through the first layer from the first surface to the second surface, and a mechanism for sensing a portion of the first diffuse light beam reflected back through the first layer to the first surface as an incident of the first diffuse light beam impinging upon the second layer. Also a method of determining the properties of a medium, the method including the steps of generating a first diffuse light beam, passing the first diffuse light beam through a first surface of a first medium having a first index of refraction, causing a portion of the first diffuse light beam to pass through the first medium, to impinge upon a second medium having a second index of refraction less than the first index of refraction and to reflect back to the first surface, and sensing the portion of the first diffuse light beam reflected back to the first surface.

Microelectronic sensor device for optical examinations in a sample medium

Abstract: The invention relates to a microelectronic sensor device with a light source (21) for emitting an input light beam (L1) into a transparent carrier (11) such that it is totally internally reflected at a contact surface (12) as an output light beam (L2), which is detected by a light detector (31) Frustration of the total internal reflection at the contact surface (12) can then for example be used to determine the amount of target particles (1) present at this surface The sensor device further comprises a refractive index measurement unit (100, 200, 300) for measuring the refractive index (nB) of the sample medium, and an evaluation unit (50) for evaluating the measurement of the light detector (31) taking the measured refractive index (nB) into account and/or for changing the conditions of total internal reflection of the input light beam (L1) The refractive index measurement unit may particularly be designed to infer the refractive index (nB) from the deflection of a test-light beam (L3) that is transmitted through the sample medium, or from a reflection of a test-light beam (L1) at an interface (12) to the sample medium In the latter case, it is possible to determine the critical angle of total internal reflection and/or to measure the reflectivity of the interface