Field consistency, detectors

The mixer consists of a photodetector and a local oscillator. We are interested in determining the signal-to-noise ratio at the output of the photodetector. The input electric field consists of three plane, parallel, coincident electromagnetic waves, which are assumed to be polarized and to impinge normally on the photodetector. Spatial first-order coherence is assumed over the detector aperture. The total incident electric field , may therefore be written as... 

In a time-of-flight (TOF) mass spectrometer, ions formed in an ion source are extracted and accelerated to a high velocity by an electric field in an analyzer consisting of a long, straight drift tube. The ions pass along the tube until they reach a detector. 

A classical setup for microwave conductivity measurements is based on the utilization of the waveguides. A simple installation consists of a microwave generator (typically a gun diode) which, when the Ka-band is used, can be operated in the frequency region of 28-40 Gc/s this is protected by an isolator against back-reflections from the rest of the microwave circuit. The microwave power is conducted by an attenuator across a circulator into the microwave conductor branch at the end of which the electrochemical cell is mounted. The microwave power reflected from the electrochemical sample is conducted via the circulator into the microwave detector. It typically consists of a diode that acts as an antenna, receiving the electrical alternating field, rectifying it, and con-... 

Another source of variability, which can have still different characteristics, is comprised of the interaction of any of the above factors with a nonlinearity anywhere in the system. These nonlinearities could consist of nonlinearity in the detector, in the spectrometer s electronics, optical effects such as changes in the field of view, and so on. Many of these nonlinearities are likely to be idiosyncratic to the cause, and would have to be characterized individually and also analyzed on a case-by-case basis. 

M256-Series Chemical Agent Detector Kit A kit used by military personnel to detect and identify field concentrations of nerve, blister or blood agent vapors. The kit consists of twelve samplers/detectors and a packet of M8 detector paper. It is used at the squad, crew or section level to detect and identify field concentrations of nerve, blister or blood agents vapors. It is usually used to determine when it is safe to unmask, to locate and identify chemical hazards, and to monitor decontamination effectiveness. 

---