Abstract:
A method of fabricating miniature quadrupole electrostatic mass filter has been previously described. The electrodes are metallised cylinders, mounted in grooves etched in oxidised silicon substrates, which are held apart at the correct spacing by cylindrical spacer rods. This invention concerns an ion source mounted on extensions of the spacer rods, which project beyond the mass filter. The ion source consists of a cold-cathode electron emitter, which emits electrons with energies sufficient to cause impact ionisation, and electrostatic optics suitable for coupling the ion flux into the mass filter. Methods of constructing a single self-aligned electron source and a similar dual source are described. Arrangements for mounting the electron source and the ion coupling lens so that the electron and ion beams travel at right angles to one another for efficient separation are described. A method of fabricating a self-aligned one-dimensional einzel electrostatic lens from metallised cylinders mounted in the silicon substrates using etched grooves is described. A method of fabricating a-self-aligned two-dimensional einzel lens from metal plates is also described.
Abstract:
A time-of-flight mass spectrometer comprises: an ionization unit for receiving an electron beam and emitting ions; a cold electron supply unit for injecting an electron beam into the ionization unit; an ion detection unit for detecting ions discharged from the ionization unit; and an ion separation unit for connecting the ionization unit and the ion detection unit, wherein the cold electron supply unit comprises a microchannel plate, which receives ultraviolet rays and emits an electron beam, ions discharged from the ionization unit pass through the ion separation unit and reach the ion detection unit, and the ion separation unit has the shape of a straight tube.
Abstract:
비행시간 질량분석기는 전자 빔을 수용하여, 이온을 방출하는 이온화부, 이온화부에 전자 빔을 주입하는 냉전자 공급부, 이온화부로부터 방출된 이온을 감지하는 이온 검출부, 및 이온화부와 이온 검출부를 연결하는 이온 분리부를 포함하되, 냉전자 공급부는 자외선을 수용하여 전자 빔을 방출하는 마이크로채널 플레이트(Microchannel Plate)를 포함하며, 이온화부에서 방출된 이온은 이온 분리부를 통과하여 이온 검출부에 도달하고, 이온 분리부는 곧은 관(straight tube) 형상을 가진다.
Abstract:
A quadrupole is filled with ions and the ions are cooled by applying a pressure and gas flow within the quadrupole. Ions are trapped in the quadrupole by applying a DC voltage and an RF voltage to quadrupole rods of the quadrupole, one or more DC voltages to a plurality of auxiliary electrodes of the quadrupole, and a DC voltage and an RF voltage to an exit lens at the end of the quadrupole. The ions are coherently oscillated after the filling and cooling by applying a coherent excitation between at least two rods of the quadrupole rods. The coherently oscillating ions are axially ejected through the exit lens and to a destructive detector for detection by changing one or more voltages of the one or more DC voltages of the plurality of auxiliary electrodes and changing the DC voltage of the exit lens.
Abstract:
본 발명은 냉전자를 이용한 음이온 발생과 전자포획 분해장치에 관한 것으로, 푸리에변환 이온싸이클로트론공명 질량분석기의 이온트랩 내에서 이온화를 위한 전자빔 발생을 하기 위하여 MCP전자증배판을 사용하되, 자외선다이오드에서 방출하는 자외선 광자를 MCP 전자증배판 전면에 주사하여 증폭된 전자빔을 획득하고, 전자집속렌즈를 이용하여 트랩내로 전자빔을 집속하여 주입하고, 이온트랩 내에서 중성분자의 음이온화를 목적으로 하는 저에너지 전자빔 방출 장치와 다중양전하를 띈 분자에 전자를 결합시켜 ECD 반응 생성하게 한다. 본 발명은 고진공 상태의 질량분석기 내부에 조사된 자외선광자로부터 많은 수의 냉전자를 발생하는 냉전자발생모듈로 구성된 냉전자를 이용한 음이온 발생과 전자포획 분해장치에 있어서, 질량분석기 내에 자외선 광자를 방출하는 다수의 자외선다이오드; 자외선다이오드로부터 자외선 광자들의 초기 전자방출을 유도 및 증폭하여 후면판에서 대량의 전자빔을 발생시키는 MCP 전자증배판; MCP 전자증배판을 통해 증폭된 전자빔을 집적하는 전자집적렌즈; 전자의 에너지와 전류를 조정하는 그리드;를 포함하여 이루어진다.
Abstract:
Mass analysers and methods of ion detection for a mass analyser are provided. An electrostatic field generator provides an electrostatic field causing ion packets to oscillate along a direction. A pulse transient signal is detected over a time duration that is significantly shorter than a period of the ion oscillation or using pulse detection electrodes having a width that is significantly smaller than a span of ion harmonic motion. A harmonic transient signal is also detected. Ion intensity with respect to mass-to-charge ratio is then identified based on the pulse transient signal and the harmonic transient signal.
Abstract:
ABSTRACT OF THE DISCLOSURE An electron source includes a first electrode, a second electrode, a thermionic element interposed between and electrically isolated from the first electrode and the second electrode, and a guard electrode interposed between and electrically isolated from the first electrode and the second electrode. The thermionic element and the guard electrode may be at substantially the same voltage. Another electron source includes a first electrode, a second electrode, a thermionic element interposed between and electrically isolated from the first electrode and the second electrode, and a thermal expansion component interposed between and electrically isolated from the first electrode and the second electrode. The thermal expansion component may be heated to cause expansion. The heating may be cycled to cause alternating expansion and contraction.
Abstract:
An electron source for electron-induced dissociation in an RF-free electromagnetostatic cell for use installation in a tandem mass spectrometer is provided. An electromagnetostatic electron-induced dissociation cell may include at least one magnet having an opening disposed therein and having a longitudinal axis extending through the opening, the magnet having magnetic flux lines associated therewith, and an electron emitter having an electron emissive surface comprising a sheet, the emitter disposed about the axis at a location relative to the magnet where the electron emissive surface is substantially perpendicular to the magnetic flux lines at the electron emissive surface.
Abstract:
The present relates to a high brightness electron gun for mass spectrometry and spectroscopy. The electron gun comprises a nano emission ionization (NEI) electron source, an electrostatic lens system and a control system. The nano emission ionization (NEI) electron source comprises a cathode having a substrate on which are mounted nano-components and an anode. The control system controls the high brightness electron gun, the beam regime and the beam physical proprieties.