Abstract:
A focused electron/bombarded (FEB) ion detector comprising an MCP, focusing means, and a collection anode disposed in a detector body. The collector anode includes a diode for receiving the focused output electron beam from the MCP. The gain between the input ion current to the MCP and the detector output signal from the diode is on the order of 1-100 million, depending on the device configuration and applied biasing voltages. A hybrid photomultiplier tube includes a photocathode, a photodiode for collecting and multiplying electrons emitted by the photocathode and providing an output signal and electrodes for focusing the electrons on the photodiode. A vacuum envelope encloses a vacuum region between photocathode and the detector. A conductor disposed on or adjacent to a sidewall of the vacuum envelope reduces the effect of electrical charges on the inside wall of the vacuum envelope on the trajectories of the electrons.
Abstract:
A photomultiplier assembly includes a tubular member of high magnetic permeability and a photomultiplier tube disposed within the tubular member. The photomultiplier tube has an encapsulated voltage distribution network attached thereto. A universal member extends longitudinally along at least a portion of the photomultiplier tube and provides a slip-fit between the photomultiplier tube and the tubular member so as to space the photomultiplier tube from the tubular member. The universal member has a retaining shoulder which projects radially inwardly between the photomultiplier tube and the voltage distribution network. A plurality of locking members are affixed between the universal member and the tubular member.
Abstract:
A semiconductor element is hermetically sealed to an evacuated electron tube envelope to provide a target electrode which collects electrons within the tube while the junction area and output electrode are external to the vacuum environment. This minimizes interaction of contaminating materials between electrodes such as a photocathode and the semiconductor.
Abstract:
A night vision system, a microchannel plate (MCP), and a planetary deposition system and methodology are provided for selectively depositing an electrode contact metal on one side of MCP channel openings. MCPs can be secured to a face of a platter that rotates about its central platter axis. The rotating platter can be tilted on a fixture surrounding an evaporative source of contact metal. A mask with a variable size mask opening is arranged between the rotating platter and the evaporative source. While the mask orbits around the evaporative source with the rotating platter, the mask does not rotate along its own axis as does the rotating platter. Depending on the opening of the non-rotating mask, and the tilt angle of the rotating platter, the respective circumferential distance around and the depth into the shaded first side of the channel opening is controlled.
Abstract:
Ion detectors of the type used in scientific instrumentation, such as mass spectrometers. More particularly, a self-contained particle detector includes an enclosure formed in part by a transmission mode secondary electron emissive element, the enclosure defining an internal environment and an external environment, wherein the transmission mode secondary electron emissive element has an externally facing surface and an internally facing surface and is configured such that impact of a particle on the externally facing surface causes emission of one or more secondary electrons from the internally facing surface.
Abstract:
The disclosure is directed to a photomultiplier tube with extended dynamic range. According to various embodiments, a repulsive electric field is introduced between a photocathode and a plurality of dynodes in order to repel or block low-energy electrons from reaching and being multiplied by the dynodes. As a result, time intervals between current peaks and drops may be decreased because the photomultiplier current will be primarily affected by high-energy electrons emitted by the photocathode in response to incident illumination versus low-energy electrons, some of which may result from dangling bonds or slow surface states after illumination no longer impinges the photocathode. Dynamic range and optical responsiveness of the photomultiplier tube are increased accordingly.
Abstract:
A microchannel plate (1) for a microchannel plate electron multiplier, comprising: a substrate (5) forming a plate having first and second opposing faces and having a plurality of parallel channels therethrough from first to second faces and; a first electrode (3) on the first face, the first electrode (3) having a first side adjacent to the substrate and a second side opposite to the first side; a second electrode (4) on the second face, the second electrode (4) having a first side adjacent to the substrate (5) and a second side opposite to the first side; and a layer (6, 7) of resistive and secondary emissive material on the second side of the first electrode and the second electrode.
Abstract:
The photomultiplier tube 1 is provided with a casing 5 made of an upper frame 2 and a lower frame 4, an electron multiplying part 33 having dynodes 33a to 331 arrayed on the lower frame 4, a photocathode 41, and an anode part 34. Conductive layers 202 are installed on an opposing surface 20a of the upper frame 2. The electron multiplying part 33 is provided with base parts 52a to 52d of the respective dynodes 33a to 33d installed on the side of the lower frame 4, and power supplying parts 53a to 53d connected to the conductive layers 202 at one end parts of the respective base parts 52a to 52d in a direction along the opposing surface 40a. The base parts 52a to 52d are constituted in such a manner that the both end parts are joined to the opposing surface 40a, the central part is spaced away from the opposing surface 40a, and a cross sectional area at the one end part on the side of each of the power supplying parts 53a to 53d is made greater than a cross sectional area at another end part.