Patent ID: 8507849

Claim:
A method of mass spectrometry comprising: providing an orthogonal acceleration Time of Flight mass analyser comprising an orthogonal acceleration region; providing a first packet or group of parent or precursor ions; accelerating said first packet or group of parent or precursor ions with a first potential so that said first packet or group of parent or precursor ions possess a first axial energy; fragmenting said first packet or group of parent or precursor ions into a first plurality of fragment or daughter ions or allowing said first packet or group of parent or precursor ions to fragment into a first plurality of fragment or daughter ions; orthogonally accelerating at least some of said first plurality of fragment or daughter ions after a first delay time; detecting fragment or daughter ions of said first plurality of fragment or daughter ions having a first range of axial energies; generating first mass spectral data relating to fragment or daughter ions of said first plurality of fragment or daughter ions having said first range of axial energies; providing a second packet or group of parent or precursor ions; accelerating said second packet or group of parent or precursor ions with a second potential different from the first potential so that said second packet or group of parent or precursor ions possess a second axial energy different from said first axial energy; fragmenting said second packet or group of parent or precursor ions into a second plurality of fragment or daughter ions or allowing said second packet or group of parent or precursor ions to fragment into a second plurality of fragment or daughter ions; orthogonally accelerating at least some of said second plurality of fragment or daughter ions after a second delay time; detecting fragment or daughter ions of said second plurality of fragment or daughter ions having a second range of axial energies; generating second mass spectral data relating to said fragment or daughter ions of said second plurality of fragment or daughter ions having said second range of axial energies; and forming a composite mass spectrum by using, combining or overlapping said first mass spectral data and said second mass spectral data.