초록 ▼

The disclosure relates to an apparatus and method for increasing the sensitivity of laser absorption detection of gas phase atoms and molecular species within a gaseous medium. An active optical element in a laser absorption detection system is translationally (longitudinally) vibrated a selected am

The disclosure relates to an apparatus and method for increasing the sensitivity of laser absorption detection of gas phase atoms and molecular species within a gaseous medium. An active optical element in a laser absorption detection system is translationally (longitudinally) vibrated a selected amplitude along the optical axis and at a desired frequency to eliminate fringes produced by interference fringe producing optical elements. The vibration frequency is preferably asynchronous with other modulation frequencies in the system.

대표청구항 ▼

In a system utilizing laser absorption for detecting gas phase atoms and molecular species within a gaseous medium, the system comprising a source for a laser beam, the coherence length of the laser source being at least equal to the distance between any fringe creating optical elements within the s

In a system utilizing laser absorption for detecting gas phase atoms and molecular species within a gaseous medium, the system comprising a source for a laser beam, the coherence length of the laser source being at least equal to the distance between any fringe creating optical elements within the system, an apparatus for improving the detection sensitivity of the system by overcoming optical interference effects comprising: an active optical element disposed on an optical path in said system; means for generating, along said optical path, physical translational vibration within said active optical element; and means for controlling the amplitude and frequency of said vibration producing means to substantially eliminate fringes produced by the fringe producing optical elements.