Abstract: A spectral measurement device includes: an optical band-pass filter section that has first to n-th wavelengths (n is an integer of 2 or more) having a predetermined wavelength width as a spectral band thereof; a correction operation section that corrects a reception signal based on an output optical signal from the optical band-pass filter section; and a signal processing section that executes predetermined signal processing based on the reception signal corrected by the correction operation section that corrects the reception signal based on the change in the spectral distribution of the reception signal.
Abstract: This invention relates to a detection system for detecting an analyte in a fluid medium. The detection system comprises a substrate that provides mechanical stability and is sized and shaped to intercept an infrared beam. A reactive material is coated on the substrate. When contacted with the analyte in the fluid medium, the reactive material reacts with the analyte and is altered. The detection system also comprises an infrared spectrometer producing the infrared beam that passes through the reactive material to a detector of the spectrometer. The alteration of the reactive material allows the spectrometer to identify and quantify the analyte. In one embodiment, the reactive material irreversibly reacts with the analyte. In another embodiment, the spectrometer is a non-ATR infrared spectrometer. In a further embodiment, the substrate is a disposable substrate.
Abstract: An illumination subsystem for use in optical analysis which provides spatially and angularly homogenized radiation to the sample being analyzed. The system eliminates the illumination system as an interferent in the overall optical analysis. Thus, modest translations or rotations of the illumination source or changing the illumination source does not require recalibration of the instrument or prior modeling of illumination variability due to such changes. Illumination stability is achieved by incorporating a light pipe which both angularly and spatially homogenizes the light. Further, a series of filters and/or lenses are incorporated to provide bandpass filtering which eliminates unwanted wavelengths or bands of wavelengths from contacting the tissue and allows for a higher signal-to-noise ratio when the sample is tissue, while preventing thermal damage.
Abstract: An optical delay apparatus that regularly alternately outputs beams having mutually different delays on one optical axis and that can variably set a delay amount of at least one beam. A motor 112 rotation-drives a rotating plate 111 in which reflective portions and transmissive portions are formed regularly alternately in the circumferential direction. When an incident beam I0 is incident to a reflective portion of the rotating plate 111, it is reflected to generate a beam I1. When the incident beam I0 is incident to a transmissive portion of the rotating plate 111, a beam I2 transmitted is reflected by a reflector 120 to become a beam I3, and the beam I3 is again transmitted by the transmissive portion of the rotating plate 111. This beam I3 has a delay different from that of the beam I1, and the beam I3 and the beam I1 advance regularly alternately in the same direction and on the same optical axis.
Abstract: A high resolution infrared densitometer system is described which comprises an intense thermal light source, an optical system for projecting first and second images of the light source along respective parallel first sample and second reference optical axes, adjustable optical attenuators for selectively balancing the light intensity of the images projected along the sample and reference axes at selected optical density, a spectrometer for filtering background radiation from the projected images except for a selected wavelength, and a detector for measuring intensities of the filtered projected images. A method for making optical density measurements is described.
June 26, 1992
Date of Patent:
November 9, 1993
The United States of America as represented by the Secretary of the Air Force
Abstract: A double beam, optical null spectrophotometer including means for automatically determining system loop gain requirements and setting the gain to the correct value for optimum response under all operating conditions. With the system ready for operation and a sample in the sample beam path, a difference signal is generated as a function of the position of a reference beam attenuator with and without a small unbalancing signal applied to the system loop. This difference signal is compared to a desired difference signal and a loop gain adjustment is made so that the difference signal will equal the desired difference signal, thereby establishing instrument gain for optimum response.
Abstract: A spectrophotometer used for measurement of the transmittance of a sample according to an optical null method, wherein light from a light source is divided into two light beams and pass through a sample cell and reference cell respectively, chopped by a chopper for alternatively supplying the light beams through a monochrometer to a light detector providing signals which are amplified and subjected to synchronous detection by a synchronous rectifier operating in synchronism with the chopper operation so as to obtain an electric signal proportional to the intensity difference between the light passed through the sample cell and that passed through the reference cell with the intensity of the light passed through the reference cell being controlled by a light attenuator connected to a recording pen until the difference signal becomes null.