Abstract:
The invention is a method and apparatus for determining characteristics of a sample. The system and method provide for detecting a monitor beam reflected off a mirror, where the monitor beam corresponds to the intensity of light incident upon the sample. The system and method also provide for detecting a measurement beam, where the measurement beam has been reflected off the sample being characterized. Both the monitor beam and the measurement beam are transmitted through the same transmission path, and detected by the same detector. Thus, potential sources of variations between the monitor beam and the measurement beam which are not due to the characteristics of the sample are minimized. Reflectivity information for the sample can be determined by comparing data corresponding to the measurement beam relative to data corresponding the monitor beam.
Abstract:
In a double beam spectrophotometer, a sample beam is irradiated to a large-sized sample in a substantially vertical direction, and the beam upwardly transmitted through the large-sized sample is reflected by a reflecting mirror and sent to an integrating sphere including a detector. A reference beam irradiated parallel to the sample beam is deflected by reflecting mirrors such that the reference beam goes around the large-sized sample, and guided to the integrating sphere. Thus, a holder is not required to correspond to a size or shape of the sample, and measurement position can be freely changed by moving the sample. Also, in case of utilizing a conventional standard sample chamber, movable reflecting mirrors are inserted in the optical paths to transfer the beams to the standard sample chamber.
Abstract:
The invention is a method and apparatus for determining characteristics of a sample. The system and method provide for detecting a monitor beam reflected off a mirror, where the monitor beam corresponds to the intensity of light incident upon the sample. The system and method also provide for detecting a measurement beam, where the measurement beam has been reflected off the sample being characterized. Both the monitor beam and the measurement beam are transmitted through the same transmission path, and detected by the same detector. Thus, potential sources of variations between the monitor beam and the measurement beam which are not due to the characteristics of the sample are minimized. Reflectivity information for the sample can be determined by comparing data corresponding to the measurement beam relative to data corresponding the monitor beam.
Abstract:
An optical spectrum analyzer includes an integrated beam switch array. As a result, a single spectrum analyzer can be amortized across multiple optical links with pigtails transmitting the optical signals from separate optical links. The switch array providing one of the optical signals as an input signal to the optical spectrum analyzer.
Abstract:
An advance in a passive, remote sensing device for measurement of atmospheric temperature utilizes an actuated modulator for periodically alternating the radiation detected by a detector at a selected infrared wavelength between the infrared radiation from the atmosphere and that from the infrared reference radiation emitted from a reference material such that the detector compares the radiation emitted from the atmosphere to that emitted by the reference material at the selected infrared wavelength in order to determine the atmosphere temperature. Preferably, the modulator is a MEMS based modulator having a movable grating formed by MEMS based fabrication techniques.
Abstract:
In an analytic spectrometer (50) having a central computer (9), permanently installed and exchangeable components (5), such as a radiation source, a detector, a beam splitter, a filter, external measurement probes and the like, each of which exhibiting a readable data carrier (7) with encoded data of parameters characterizing the respective component (5), the data media (7) can be written to and contains changeable time dependent data concerning the history and/or the actual properties of the corresponding component (5) for example length of operation, performance deterioration parameters or calibration curves of the component (5). These data can be continuously adjusted by the central computer (9) to the current state of the component (5) so that the data medium (7) connected to the component (5) can immediately supply information concerning the current actual properties of the component (5) when installing the component (5) in another spectrometer.
Abstract:
A probe, for use with a spectrophotometer, which senses the reflectance of a sample remote from the spectrophotometer. The probe includes a housing having a probe portion positionable proximate the sample, and an integrating chamber disposed within the probe housing and having a radiation input port, a sample port for passing diffused radiation to the sample and returning reflected radiation from the sample, a reference port, and an exit port to receive radiation reflected from the sample through the sample port. The probe further includes a guide for directing radiation to the radiation input port from a radiation source, and an element, responsive to the exit port and the reference port, for selectively conveying reflected radiation from the sample and the wall of the integrating chamber in the probe to the remote spectrophotometer.
Abstract:
A spectrmeter radiation transmission system is disclosed which permits concurrent availability of numerous alternative accessory devices by conserving radiation throughput. Parabolic reflectors are used to provide alternating collimated and confocal segments of radiation, thereby largely eliminating the problem of vignetting (i.e., loss of radiation throughput due to beam size expansion). Modular enclosure elements are provided, inside which the radiation path travels between the parabolic reflectors.
Abstract:
A spectrophotometer optical section is presented which employs a fine positioning beam director which corrects for any deflections of the output beam path and accurately positions the optical beam on the detector slit of the spectrograph. The detector slit is chosen to have a size slightly smaller than the size of the optical beam at the detector slit to have high slit throughput without introducing spurious absorption. The sample cells need not be rigidly mounted thereby enabling use of a sample cell and cell holder which allows quick, easy interchange of cells.
Abstract:
Spectrum analyzer for the light absorption of a solution comprising a small transparent measuring cell containing the solution; a light source; means for dividing the beam of light of the source into two beams, one being the reference beam and the other the measuring beam transmitted respectively to a reference absorber element and to the measuring cell; means for selecting the measuring wavelength; means for modulating the reference and measuring beams which have respectively traversed the absorber element and the measuring cell; means for detecting the energies of each of the modulating beams after they have traversed the reference absorber element and the sample; the modulation means comprising alternate transparent and bireflecting sectors in front of each of the beams which have passed through the reference absorber and the measuring cell, said sectors being associated with means for selecting the wavelength of the beams in such a way that, as a function of the successive positions of the sectors relative to the beams, the detection means alternately receive the light transmitted by the sample and that transmitted by the absorber, the latter being such that it can independently absorb radiations of different wavelengths transmitted by the source and corresponding to the wavelength of the radiations absorbed by the components of the solution, means for comparing the energies of the modulated beams connected to detection means, wherein the modulation means are positioned directly behind the cell along the path of the divided measuring beam and immediately behind the absorber element on the path of the reference beam, the means for dividing the beam of the source being arranged in such a way that the measuring beam is converged on the cell.