Abstract:
A tunable radiation emitting structure comprising a discontinuous conducting interface having periodic or quasi-periodic features, wherein the structure emits narrowband terahertz radiation when heated is disclosed.
Abstract:
A spectrometer includes: a lighting device (LSRC) configured to generate a light beam covering a wavelength band, a probe configured so that the light beam coming from the lighting device interacts with a fluid to be analyzed, and a spectrum analyzing device configured to receive the light beam after it has interacted with the fluid to be analyzed, and to provide light intensity measurements for various ranges of wavelengths. The lighting device includes several light-emitting components (1a-1c) emitting light in various ranges of wavelengths, and a mixing optical component (3) fixed onto the emitting surface of the light-emitting components (1a-1g), to combine the light flows emitted by the light-emitting components into a resulting light beam covering the wavelength band, and guide the resulting light flow to the probe.
Abstract:
Provided are a terahertz wave transmission and reception (Tx/Rx) module package and method of manufacturing the same. The complete and separate terahertz wave Tx/Rx module package is implemented by simply aligning a silicon ball lens, a photoconductive antenna and a focusing lens, and thus facilitates generation or measurement of a terahertz wave. The terahertz wave Tx/Rx module package and method can remarkably reduce time and cost required to build a terahertz wave generation and measurement system, and simplify and miniaturize the terahertz wave generation and measurement system. In addition, characteristics of a terahertz wave generated by the photoconductive antenna can be simply measured. Furthermore, the terahertz wave Tx/Rx module package can be stored and transported with a photoconductive antenna, a silicon ball lens and a focusing lens kept aligned as they are, and also it is possible to minimize pollution of terahertz wave devices caused by surroundings.
Abstract:
There is provided an infrared light source that has a simple structure and radiates infrared rays polarized in a specific direction and having a specific wavelength. The infrared light source (100) comprises a heat generator (107) and a latticework (101) in which a dielectric part (105) and a metal part (103) are alternately formed at a constant pitch in a constant direction. The infrared rays are radiated in a direction perpendicular to the surface of the latticework and are polarized in the direction indicated by an arrow A. If the constant pitch is denoted by P, the width of the dielectric part in the constant direction by T, and the specific wavelength by λ, for arbitrary P and T that meet the inequalities 0
Abstract:
A miniature, battery operated plastic module designed to project at least three different frequencies of energy from light emitting diodes is described. A first frequency is between 390 nm-420 nm just above harmful Ultraviolet Frequencies, a second frequency is between 850 nm-1200 nm in the infrared band and a third frequency is for a visible white light. The light emitting module has a base unit, the unit including a pulsed LED that emits an ultraviolet wavelength of light adapted to focus on a surface having phosphorescence means on the surface to activate the phosphorescence. The light emitting module may also have a base unit which includes a pulsed LED that emits an infrared wavelength of light adapted to penetrate a particular atmosphere. The module may also provide optional power for external items in addition to the three frequencies.
Abstract:
A thermal emitter device includes a cavity structure that comprises an active medium for allowing thermal emissions to occur. A photonic crystal structure is positioned on one side of the cavity structure. The photonic crystal structure comprises alternating layers of high index and low index materials and acts as a first mirror for the cavity structure. A highly reflective mirror structure is positioned on another side of the cavity structure and acting as both the high-temperature source of radiation and a second mirror for the cavity structure.
Abstract:
A diode laser spectroscopy gas sensing apparatus having a diode laser with a select lasing frequency, a pitch optic coupled to the diode laser with the pitch optic being operatively associated with a process chamber and oriented to project laser light along a projection beam through the process chamber. This embodiment additionally includes a catch optic in optical communication with the pitch optic to receive the laser light projected through the process chamber and an optical fiber optically coupled to the catch optic. In addition, the catch optic is operatively associated with a catch side alignment mechanism which provides for the alignment of the catch optic with respect to the projection beam to increase a quantity of laser light received by the catch optic from the pitch optic and coupled to the optical fiber and a detector sensitive to the select lasing frequency optically coupled to the optical fiber. The catch side alignment mechanism may consist of means to tilt the catch optic along a first axis and a second axis orthogonal to the first axis with both the first and second axes being approximately orthogonal to the projection beam.
Abstract:
A field test-kit for analyzing arsenic concentration in water samples is provided. The kit includes a portable infrared beam photometer for measuring light absorbance in aqueous specimens. An infrared light emitting diode is configured to direct a beam of light through a specimen. A photodetector diode measures the intensity of light passing through the specimen. The photodetector output voltages relate to the light absorbed in the specimen and are displayed on a liquid crystal display screen. The kit is assembled using off-the-shelf electronic and opto-electronic components that have low power requirements. Dry cell batteries or solar cells power the kit. To test for arsenic, molybdenum based chemistries are used to selectively bind and convert arsenates and phosphates in the specimen into molybdenum-blue color complexes. The light absorbance of a specimen with both arsenates and phosphates bound in molybdenum-blue color complexes is compared to that of a reference specimen in which phosphates but not arsenates are bound and converted. The differential light absorbance of the two specimens is used to arrive at a quantitative value for the arsenic concentration in the water sample.
Abstract:
A catch side optical system for use in diode laser spectroscopy consisting of a catch side optic optically coupled to a catch side multimode optical fiber and means to mechanically manipulate a section of the catch side multimode optical fiber to minimize catch side mode noise. The mechanical manipulation may consist of twisting the catch side multimode optical fiber around its longitudinal axis. The means to mechanically manipulate the section of the catch side multimode optical fiber in the above fashion may consist of a motor associated with the catch side multimode optical fiber such that a section of fiber is held fast relative to a shaft position of the motor and the motor shaft is repetitively swept through +360 degrees and −360 degrees of motion. The frequency of the motor shaft sweep may be at least 10 Hz to enable effective averaging of the transmitted signal and thereby reduce the effect of catch side mode noise.
Abstract:
A spectrometer system includes a thermal light source for illuminating a sample, where the thermal light source includes a filament that emits light when heated. The system additionally includes a spectrograph for measuring a light spectrum from the sample and an electrical circuit for supplying electrical current to the filament to heat the filament and for controlling a resistance of the filament. The electrical circuit includes a power supply that supplies current to the filament, first electrical components that sense a current through the filament, second electrical components that sense a voltage drop across the filament, third electrical components that compare a ratio of the sensed voltage drop and the sensed current with a predetermined value, and fourth electrical components that control the current through the filament or the voltage drop across the filament to cause the ratio to equal substantially the predetermined value.