Spectral analyzer with new high efficiency collection optics and method of using same

Abstract

A spectral analyzer has a high efficiency optical collector having a first concave reflector portion and an opposed second concave reflector portion providing an exit passage therethrough, and a light emitting source of a predetermined wavelength range is positioned in the collector so that the light is collected and directed to the exit passage. A specimen holder is positioned adjacent the exit passage and has windows at its entrance and exit ends. An elongated reverse non-imaging optical member which has a peripheral wall reflecting light rays entering through the exit window of the holder reduces the angle of the rays relative to the optical axis of the optical member as they pass therethrough. The light passing through the exit end of the optical member enters a detector assembly including at least one photo detector sensitive to a predetermined wavelength of light, and at least one optical filter disposed between the optical member and the photodetector to pass light of the predetermined wavelength.

Description

BACKGROUND OF THE INVENTIONThe present invention relates to a spectral analyzer and, more particularly to an improved spectral analyzer which is adapted for measurement of multiple components of a specimen.Spectroscopic analyzers are now widely employed in the analysis of various types of specimens including gases, solids and liquids. This is done by employing specimen holders or light guides of different types to enable absorption or modification of light transmitted therethrough or absorbed at an interface with the specimen. Although many analyzers are designed to operate and measure the effect of a specimen upon light rays of a single wavelength band, some employ two or three photodetectors to concurrently measure the several different components.Although the infrared wavelength is most widely utilized, it is also possible to use light rays in the ultraviolet wavelength, in the visible light wavelength, and even broad band light rays depending upon the specimen and the components...

AI Technical Summary

Benefits of technology

In use, power is provided to the light source to effect emission of light rays which are collected and reflected to the exit aperture from the collector and i

Problems solved by technology

Some of the problems experienced with existing analyzers include relatively low signal to noise ratio and poor collection efficiency.

As a result, relatively long cells for gaseous and other specimens are required.

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