31 results about "Gas electron multiplier" patented technology

To attain objects to reduce the spread of electrons as compared with a conventional one without degrading the multiplication factor of electrons; to provide a large electron multiplication factor; and to improve positional resolution, there is provided a gas electron multiplier using interaction between radiation and gas through photoelectric effects including: a chamber filled with gas and a single gas electron multiplication foil arranged in the chamber wherein the gas electron multiplication foil is made of a plate-like multilayer body composed by having a plate-like insulation layer made of a macromolecular polymer material having a thickness of around 100 μm to 300 μm and flat metal layers overlaid on both surfaces of the insulation layer, and the plate-like multilayer body is provided with a through-hole structure.

A dosimeter based on a gas electron multiplier and method of use thereof for measurement of doses of therapeutic radiation to which a tissue-phantom is exposed. Subsequent to the in-phantom measurement and verification of radiation beam delivery, radiation can be effectively delivered to a human target organ, based on the verification of radiation quantities to which the phantom was exposed. Use of a gas electron multiplier-based dosimeter facilitates precise and accurate verification of the radiation dose within a phantom by taking measurements in real time, with no need for subsequent film processing.

The invention relates to a detecting unit for detecting ionizing radiation. The device comprises a converter unit for the amplification of ionizing radiation and a read-out unit, wherein the converter unit comprises a converter and a gas-electron multiplier, wherein said converter comprises a substrate with an ionizing radiation-receiving major surface and an electron-emitting major surface and a stack of accelerator plates in contact with the electron-emitting major side, wherein said stack comprises a plurality of perforated accelerator plates wherein the perforations of the perforated accelerator plates are aligned to form a matrix of blind holes.

A readout board for use in a micropattern gas detector comprises a plurality of detector pads arranged into a plurality of consecutive layers that are separated by dielectric spacer material. An electron cloud hitting the front side of the readout board will induce a charge on one of the detector pads of the uppermost layer. By capacitive coupling, the signal will propagate downwards through the consecutive layers until it reaches the bottom layer, from which the charges are read out and analyzed. The position of the impact can be determined by comparing the charges that have spread to neighboring readout pads. Since only the bottommost layer of the readout pads needs to be connected to readout electronics, incident particles can be localized at high precision despite the relatively large size of the readout pads in the bottom layer. The invention is effective both in a gas electron multiplier (GEM) and in a MicroMegas detector.

The invention discloses a sliding type self-tensioning method for installing and manufacturing a large-area gas electron multiplier (GEM) detector. The sliding type self-tensioning method comprises a GEM film fixing method and a method for applying a tension force on the GEM film. Two kinds of pad strips are used for fixing a drift electrode and four edges of a GEM film. The first kind of pad strips are arranged in the middle between the drift electrode and the GEM film edge; and the second kind of pad strips are arranged at positions, approaching corner, of the two ends of the drift electrode and the GEM film edge. Sliding blocks are fixed at the outer sides of the two kinds of pad strips; and screw holes are formed in the outer sides of the sliding blocks. Clamp grooves are formed in the main frame; the parts, with the screw holes, of the outer sides of the sliding blocks are clamped into the clamp grooves for positioning; and through holes are formed in the walls of the clamp grooves; and bolts pass through the through holes and are screwed into the screw holes for tensioning. According to the invention, the method has all advantages of the self-tensioning method but problems that exist when the GEM detectors with the levels above nanometer level are manufactured are solved. Therefore, the provided method has the high design flexibility and can be used for manufacturing large-area GEM detectors with all shapes and various dimensions.

The invention discloses a method for manufacturing a thick gas electron multiplication detector membrane plate, which is characterized in that it comprises the following steps: cutting and cleaning double-sided copper-clad plates; drilling positioning holes; pressing photoresist dry films on both sides simultaneously; The outer graphic film and the circuit board with the photoresist dry film pressed are aligned and placed on the exposure machine for exposure; develop, etch to remove copper, and remove the photoresist dry film; CNC machine tools punch out holes on the double-sided copper clad board Array; spray double-sided copper-clad board. The advantage of the present invention is that: it adopts the whole board micro-etching process to manufacture THGEM diaphragms in a large area, and has successfully produced THGEM diaphragms of 300mm×300mm, and the uniformity of the rim is consistent; the use of fully automatic circuit board manufacturing equipment , can be mass-produced, and the yield rate is above 95%; THGEM membrane plate and readout anode plate are independent of each other, and can be designed and processed into different sizes and shapes according to needs.

Methods for manufacturing a gas electron multiplier. One method comprises a step of preparing a blank sheet comprised of an insulating sheet with first and second metal layers on its surface, a first metal layer hole forming step in which the first metal layer is patterned by means of photolithography, such as to form holes through the first metal layer, an insulating sheet hole forming step, in which the holes formed in the first metal layer are extended through the insulating layer by etching from the first surface side only, and a second metal layer hole forming step, in which the holes are extended through the second metal layer. Alternatively, the second metal layer hole forming step is performed by electrochemical etching, such that the first metal layer remains unaffected during etching of the second metal layer. In another embodiment, in the second metal layer hole forming step, the first and second metal layers are etched from the outside, thereby reducing the initial thicknesses of the first and second metal layers and the second metal layer is simultaneously etched through the holes in the first metal layer and the insulating sheet, said etching being maintained until the holes extend through the second metal layer, wherein said initial average thickness of the first and second metal layers is between 6.5 μm and 25 μm, preferably between 7.5 μm and 12 μm.

A detector for radiation, particularly high energy electromagnetic radiation is provided. The detector includes a converting section including a cathode for converting the radiation incident on the converting section in electrons by the photoelectric effect. The detector further includes a gas electron multiplier for generating an electron avalanche from electrons which are generated by the converting section and enter the gas electron multiplier, the gas electron multiplier including a first electrode, a dielectric layer and a second electrode, the first electrode being disposed at a first side of the dielectric layer adjacent to the converting section and the second electrode being disposed at a second side of the dielectric layer opposite to the first side. The gas electron multiplier includes a number of holes filled with gas, the holes extending through the first electrode, the dielectric layer and the second electrode.