Schematic showing incident particles hitting a scintillating crystal, triggering the release of photons which are then converted into photoelectrons and multiplied in the photomultiplier.

Schematic of a Geiger counter using an " end window " tube

Fig. 4 Schematic diagram of a dilution refrigerator precooled by a two-stage pulse tube refrigerator, indicated by the dotted rectangle. Modern dilution refrigerators can be precooled not by liquid nitrogen, liquid helium, and a 1K bath, but by a cryocooler as shown in Fig. 4.

Schematic of image orthicon tube.

Schematic of vidicon tube.

Schematic of a Plumbicon tube.

Fig. 7 Schematic diagram of a Stirling-type single-orifice PTR. The pulse tube refrigerator is treated in a separate article.

Schematic of Jupiter's magnetosphere and the components influenced by Io ( near the center of the image ): the plasma torus ( in red ), the neutral cloud ( in yellow ), the flux tube ( in green ), and magnetic field lines ( in blue ).

Schematic diagram of a marine-type water tube boiler

Schematic representation of a cold cathode voltage-regulator tube

Schematic of vidicon image tube.

Schematic representation of a electrical circuit | circuit where a source is coupled to a electrical load | load with a transmission line having characteristic impedance.

Schematic of the weakly coupled high temperature situation in which the magnetic moments of conduction electrons in the metal host pass by the impurity magnetic moment at speeds of v < sub > F </ sub >, the Fermi velocity, experiencing only a mild antiferromagnetic correlation in the vicinity of the impurity.

In a photomultiplier tube, every photon striking the photocathode initiates an avalanche of electrons that produces a detectable current pulse.

Currently available scanners typically use charge-coupled device ( CCD ) or contact image sensor ( CIS ) as the image sensor, whereas older drum scanners use a photomultiplier tube as the image sensor.

On November 12, 2001, about 6, 600 of the photomultiplier tubes ( costing about $ 3000 each ) in the Super-Kamiokande detector imploded, apparently in a chain reaction or cascade failure, as the shock wave from the concussion of each imploding tube cracked its neighbours.

Although wide bandwidth sources typically suffer from low spectral power per unit frequency, the photomultiplier tube offers high gain ( about ) amplification of photon shot noise, making it advantageous over other lower gain noise sources.

After passing a pinhole, the light intensity is detected by a photodetection device ( usually a photomultiplier tube ( PMT ) or avalanche photodiode ), transforming the light signal into an electrical one that is recorded by a computer.

From there, a fiber optic will transfer the light out of the microscope where it will be separated by a monochromator and then detected with a photomultiplier tube.

The primary advantages to the electron microscope based technique is the ability to resolve features down to 1 nanometer, the ability to measure an entire spectrum at each point ( hyperspectral imaging ) if the photomultiplier tube is replaced with a CCD camera, and the ability to perform nanosecond-to picosecond-level time-resolved measurements if the electron beam can be " chopped " into nano-or pico-second pulses.

The detector is typically a photomultiplier tube, a photodiode, a photodiode array or a charge-coupled device ( CCD ).

UV-visible spectroscopy of microscopic samples is done by integrating an optical microscope with UV-visible optics, white light sources, a monochromator, and a sensitive detector such as a charge-coupled device ( CCD ) or photomultiplier tube ( PMT ).

Dynodes inside a photomultiplier tube

The invention of the photomultiplier is predicated upon two prior achievements, the discoveries of the photoelectric effect and the secondary emission ( i. e., the ability of electrons in a vacuum tube to cause the emission of additional electrons by striking an electrode ).

The ingredients for inventing the photomultiplier were coming together during the 1920s as the pace of vacuum tube technologies accelerated.

By October 1935, Vladimir Zworykin, George Ashmun Morton, and Louis Malter of RCA in Camden, NJ submitted their manuscript describing the first comprehensive experimental and theoretical analysis of a multiple dynode tube — the device later called a photomultiplier — to Proc.

There are two common photomultiplier orientations, the head-on or end-on ( transmission mode ) design, as shown above, where light enters the flat, circular top of the tube and passes the photocathode, and the side-on design ( reflection mode ), where light enters at a particular spot on the side of the tube, and impacts on an opaque photocathode.

After fifty years, during which solid-state electronic components have largely displaced the vacuum tube, the photomultiplier remains a unique and important optoelectronic component.

Behind this grid system, an image dissector tube ( photomultiplier type detector ) with a sensitive field of view of about 38 arc-sec diameter converted the modulated light into a sequence of photon counts ( with a sampling frequency of 1200 Hz ) from which the phase of the entire pulse train from a star could be derived.

Other hardware components were supplied as follows: the beam-combining mirror from REOSC at Saint Pierre du Perray ; the spherical, folding and relay mirrors from Carl Zeiss AG in Oberkochen ; the external straylight baffles from CASA in Madrid ; the modulating grid from CSEM in Neuchatel ; the mechanism control system and the thermal control electronics from Dornier Satellite Systems in Friedrichshafen ; optical filters, the experiment structures and the attitude and orbit control system from Matra Marconi Space in Velizy ; instrument switching mechanisms from Oerlikon-Contraves in Zurich ; the image dissector tube and photomultiplier detectors assembled by the Dutch Space Research Organisation, SRON in The Netherlands ; the refocusing assembly mechanism designed by TNO-TPD in Delft ; the electrical power subsystem from British Aerospace in Bristol ; the structure and reaction control system from Daimler-Benz Aerospace in Bremen ; the solar arrays and thermal control system from Fokker Space System in Leiden ; the data handling and telecommunications system from Saab Ericsson Space in Gothenburg ; and the apogee boost motor from SEP in France.

A sensitive photomultiplier tube ( PMT ) measures the light from the crystal, and the output signal is fed to an electronic amplifier and other electronic equipment to count and possibly quantify the amplitude of the signals produced by the photomultiplier.

The industrial contamination monitoring detector, consisting of a scintillator and photomultiplier tube, finds wide application in the field of radioactive contamination monitoring of personnel and the environment.

The spectrometer consists of a suitable scintillator crystal, a photomultiplier tube, and a circuit for measuring the height of the pulses produced by the photomultiplier.

** Photodiode, photoresistor, phototransistor, photomultiplier tube – converts changing light levels into electrical signals

A scintillation detector or scintillation counter is obtained when a scintillator is coupled to an electronic light sensor such as a photomultiplier tube ( PMT ) or a photodiode.

# Light detection systems that may use amplification e. g. by a photodiode or a photomultiplier tube or a cooled charge coupled device.

Each detector had a central scintillation spectrometer crystal of NaI ( Tl ) 12 in ( 303 mm ) in diameter, by 4 in ( 102 mm ) thick, optically coupled at the rear to a 3 in ( 76. 2 mm ) thick CsI ( Na ) crystal of similar diameter, viewed by seven photomultiplier tubes, operated as a phoswich: i. e., particle and gamma-ray events from the rear produced slow-rise time (~ 1 μs ) pulses, which could be electronically distinguished from pure NaI events from the front, which produced faster (~ 0. 25 μs ) pulses.

A gamma camera consists of one or more flat crystal planes ( or detectors ) optically coupled to an array of photomultiplier tubes, the assembly is known as a " head ", mounted on a gantry.

For all seven modules, the unwanted background effects of particles or photons entering from the rear was suppressed by a " phoswich " design, in which the active NaI detecting element was optically coupled to a layer of CsI on its rear surface, which was in turn optically coupled to a single photomultiplier tube for each of the seven units.

These are detected when they reach a scintillator in the scanning device, creating a burst of light which is detected by photomultiplier tubes or silicon avalanche photodiodes ( Si APD ).

The secondary electrons are first collected by attracting them towards an electrically biased grid at about + 400 V, and then further accelerated towards a phosphor or scintillator positively biased to about + 2, 000 V. The accelerated secondary electrons are now sufficiently energetic to cause the scintillator to emit flashes of light ( cathodoluminescence ), which are conducted to a photomultiplier outside the SEM column via a light pipe and a window in the wall of the specimen chamber.

The use of a scintillator in conjunction with a photomultiplier tube finds wide use in hand-held survey meters used for detecting and measuring radioactive contamination and monitoring nuclear material.

This assumption is based on two requirements: ( 1 ) that the light output of the scintillator is proportional to the energy of the incident radiation ; ( 2 ) that the electrical pulse produced by the photomultiplier tube is proportional to the emitted scintillation light.

The scintillator material gives off flashes of light in response to the gamma rays and the light flashes are detected by photomultiplier tubes.

The water tanks were sandwiched between three scintillator layers which contained 110 five-inch ( 127 mm ) photomultiplier tubes.