Opinion ID: 764877
Heading Depth: 2
Heading Rank: 2

Heading: The Accused Device and Technique

Text: 18 Bruker's ESQUIRE-LC spectrometer operates in a manner similar to the disclosed embodiment of the '884 patent in all material respects, except in the manner in which ions are ejected from the trapping field for detection. As previously mentioned, the patented embodiment ejects ions from the trap by changing or scanning the quadrupole field to render trapped ions unstable with respect thereto, i.e., by transferring previously trapped ions outside of the stability diagram. In addition, the end caps 12 and 13 of the patented embodiment are grounded. See Figure 1 supra. The ESQUIRE device, in contrast, ejects ions without transferring the ions outside of the stability diagram. Instead, the trapped ions are ejected by applying a supplementary AC voltage to one of the end caps. This arrangement is depicted in Bruker's Primer on the operation of the ESQUIRE machine, with the supplementary AC voltage labeled auxiliary dipolar amplitude: 19 NOTE: OPINION CONTAINS TABLE OR OTHER DATA THAT IS NOT VIEWABLE 20 Joint App. at A3300. 21 In the Bruker technique, certain ions are trapped in the storage area, just as in the patented embodiment. Each of these ions orbits within the trap with a secular frequency, which is dependent on the quadrupole scanning parameters. During analysis, one of these parameters (usually V) is changed to bring the secular frequency of a given ion into parity with the fixed frequency of the supplementary voltage (or a harmonic thereof). When this happens, the field produced by the supplementary voltage and the ion are in resonance. Resonance causes the ion to gain kinetic energy from the supplementary field, just as a parent can impart additional energy to a child on a swing by pushing the child at the same moment on each 'orbit' of the swing. As the ion gains energy, its trajectory, like that of the swinging child, will increase over time, until the ion exits the trap ... and strikes a detector. Commissioner's Brief at 7. Eventually, as scanning continues, the secular frequency of another ion species is brought into parity with the fixed supplemental voltage frequency and is ejected, and so on. The important point is that, in contradistinction to the patented embodiment, the ions ejected from the trapping field are stable from the standpoint of the stability diagram. 22 Because the Bruker technique involves principles of resonance, it is referred to in the literature as resonance ejection, whereas the patented embodiment employs a form of nonresonance ejection.