High clarity mass spectrometer capable of multiple simultaneous detection

A mass spectrometer, comprising:

• inlet means for receiving a beam of charged particles having horizontal trajectory components in a radial plane and vertical trajectory components transverse to said radial plane;
• first deflection means for impinging a first deflection, in the radial plane, to the beam of particles received from said inlet means, said first deflection varying with the velocity of the particles;
• correcting means, arranged on the path of the particle beam, for compensating for second order aperture aberrations of said first deflection means for trajectories in the radial plane;
• beam shaping means for independently adapting the horizontal and vertical trajectory components of the beam received from said first deflection means to provide a parallel beam having a thin vertical section transverse to said radial plane, and for passing the parallel beam through an aperture slot;
• and
• second deflection means for impinging a second deflection, in the radial plane, to the beam of particles received from said aperture slot, said second deflection varying with both the mass and energy of the particles, and the energy dependent component of the second deflection being substantially compensated for by said first deflection in the first deflection means,
• said second deflection means having a planar inlet face inclined by an angle .epsilon., with respect to a normal to the axis of the particle beam incident thereon, in the direction of the deflection in said second deflection means, and having a planar outlet face in a plane passing through the intersection of the inlet face and the axis of the particle beam, so that the following equation is satisfied
• tan (.theta./2) tan (.theta.-.epsilon.)=2,
• where .theta. designates the angle of deflection of the beam in said second deflection means.