The invention relates to time-of-flight mass spectrometers, equipped with ion reflector and ion detector, with orthogonal ion injection and outpulsing of a segment of the ion beam perpendicular to the direction of injection in a pulser. The invention is directed to a time-of-flight mass spectrometer in which a reflector and an ion detector each have an angular offset about an axis that is perpendicular to the respective directions of injection and deflection. This allows a large distance to be used between the pulser and detector with the highest possible utilization of ions.