The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 13, 1990
Filed:
Feb. 14, 1990
Wilfried Szymczak, Lohhof, DE;
Gesellschaft fur Strahlen- und Umweltforschung mbH (GSF), Neuherberg, DE;
Abstract
An apparatus for counting individual particles in time-of-flight mass spectrometry includes a device for producing secondary particles at a high repetition rate by pulsed ion bombardment of a sample from which the secondary particles originate, an accelerator for accelerating the secondary particles, and a detector for detecting arrival of the secondary particles and producing an output signal indicating detection of a secondary particle. The output signal of the detector has a magnitude which is independent of the number of simultaneously impinging secondary particles. A fast pulse amplifier recieves the output signals and amplifies them. A fast discriminator receives the amplified signals and converts them into unit pulses, and supplies the converted signal to a shifting and attenuating device, for shifting and attenuating the unit pulses in a selected time relationship so that a noise-distorted base line of the unit pulses does not lie in a predetermined measuring range, and so that a plateau of the unit pulses lies in the predetermined measuring range. A transient recorder fed by the shifting ad attenuating device produces an output signal at a high voltage level for a short time interval in response to each of the shifted and attenuated unit pulses, representing a mass spectrum of the secondary particles.