Abstract: A sensing apparatus and method for use in the optical absorption analysis of the NO2 content of a gas sample. The apparatus and method employ radiation from a semiconductor radiation source. The emission spectrum of the radiation has a maximum wavelength of about 600 nm, preferably 380-520 nm. The radiation is passed through the gas sample and sensed by a detector to provide an output signal indicative of the NO2 content of the gas sample. A pair of alternately energized radiation sources may also be used. The sensor apparatus and method may be employed in conjunction with other gas sensing apparatus and methods, such as IR CO2 measurement or NO sensing.

Abstract: A radiation source assembly and transducer incorporating same are suitable for use in measuring spectral absorption properties of a substance to be analyzed, such as a gas. The radiation source assembly has an optical axis. A measuring radiation source provides radiation in the direction of the axis and a reference radiation source provides radiation in the direction of the axis. An optical diffuser is spaced from the radiation sources along the axis. Radiation from the measuring radiation source and radiation from the reference radiation source are applied to the diffuser and the diffuser forms an exiting radiation beam for the assembly from the radiation of the measuring radiation source and reference radiation source. The exiting radiation beam extends along the axis.

Abstract: A radiation source assembly and transducer incorporating same are suitable for use in measuring spectral absorption properties of a substance to be analyzed, such as a gas. The radiation source assembly has an optical axis. A measuring radiation source provides radiation in the direction of the axis and a reference radiation source provides radiation in the direction of the axis. An optical diffuser is spaced from the radiation sources along the axis. Radiation from the measuring radiation source and radiation from the reference radiation source are applied to the diffuser and the diffuser forms an exiting radiation beam for the assembly from the radiation of the measuring radiation source and reference radiation source. The exiting radiation beam extends along the axis.

Abstract: An optical sensor for non-invasively measuring the content or composition of one or more chemical components within especially a living tissue of a body portion. Radiation sources (38), emit measuring radiation with at least two wavelengths to a portion (6) of the body of a patient. A detector (37) receives the measuring radiation having passed through said body portion of a patient and converts same to electric form. At least one radiation transfer section is located between either the radiation sources or respectively the detectors and the external surface (50) of the body portion of a patient. The radiation transfer section includes measuring-radiation transmitting ends. An outer end (16, 26) facing the external body surface (50) has a surface area which is generally larger than the surface area of an inner end (13a; 19a) facing any given radiation sources or respectively detectors. A measuring-radiation diffusely reflecting surface (14, 17) is positioned between the ends.

Abstract: An apparatus and method for the identification of one or more anesthetic or other gases included in the respiratory air of a patient, said identification being effected within the infrared range 3-4 .mu.m. The appratus comprises a radiation source (4), a chamber (1) for receiving therein a gas or gases to be examined, an optical filter (7) for passing the radiation exiting the chamber therethrough, an optical focusing device (12) through or via which the incoming radiation travels, a radiation detector (10) and a measuring processor (19) which performs the measuring and identification. The transmission band of the optical filter (7) or a combination of successive filters is within a range of 1.5%-0.4% of the mean transmission wavelength and the ray arriving at filter (7) has an angle of incidence between 10.degree.-60.degree., the measuring effected within this range being performed at more than two angles.