Continuous dynode channel type secondary electron multiplier

Claim 2

A channel-type secondary electron multiplier, comprising: a pair of parallel spaced flat plates of an electrically insulating material defining an electron multiplying channel therebetween; a plurality of secondary electron emissive film sections made of a secondary electron emissive material having a finite surface electrical resistivity, said film sections being disposed on said plates and spaced apart from each other on the respective plates a distance substantially less than the width of a given film section, the position of the film sections along one plate being staggered with respect to those along the other plate; a plurality of resistance elements disposed on said plates in the spaces defined between adjacent emissive film sections and electrically coupled thereto to form a series electrical circuit of alternating resistance elements and secondary emissive film sections; a D.C. voltage source coupled across the series combination of resistance elements and emissive film sections on each plate; and means for collecting the multiplied secondary electrons.

Claim 3

A multiplier according to claim 1, wherein said resistance elements are formed of a material having a substantially different resistivity than said secondary electron emissive film material, said resistance elements being directly connected electrically to immediately adjacent ones of said emissive film sections.

Claim 4

A channel-type secondary electron multiplier, comprising: a pair of parallel spaced flat plates of an electrically insulating material defining an electron multiplying channel therebetween; a continuous coating formed of a secondary electron emissive material having a finite surface electrical resistivity and deposited on the opposed surfaces of said flat plates, said coating being formed of alternating first and second portions, said first portions having a substantially larger surface area than said second portions, the first portions disposed on one plate being longitudinally staggered in relation to the corresponding first portions disposed on the other plate, said second portions being formed in a portion of the spaces defined between adjacent first portions on each plate, said second portions being provided primarily as voltage dividers for positively and discontinuously increasing voltage potentials across successive first portions in the direction of flow of a D.C. voltage source connected across the longitudinally opposite ends of the coatings on each of said plates; and means at the output of said multiplier for collecting multiplied secondary electrons.

Claim 5

A channel-type secondary electron multiplier, comprising: a pair of parallel spaced flat plates of an electrically insulating material defining an electron multiplying channel therebetween; a continuous coating formed of a secondary electron emissive material having a finite surface electrical resistivity and deposited on the opposed surfaces of said flat plates, said coating being formed of alternating first and second portions, said first portions having a substantially larger surface area than said second portions, the first portions disposed on one plate being longitudinally staggered in relation to the corresponding first portions disposed on the other plate, said second portions being formed in a portion of the spaces defined between adjacent first portions on each plate, said second portions being provided primarily as voltage dividers for positively and discontinuously increasing voltage potentials across successive first portions in the direction of flow of a D.C. voltage source connected across the longitudinally opposite ends of the coatings on each of said plates; and means at the output of said multiplier for collecting multiplied secondary electrons.

Claim 6

The multiplier according to claim 3, wherein said first and second portions are disposed in a zig-zag pattern on each plate.

Claim 7

A channel-type secondary electron multiplier, comprising: a pair of parallel spaced flat plates of an electrically insulating material defining an electron multiplying channel therebetween; a plurality of secondary electron emissive film sections made of a secondary electron emissive material having a finite surface electrical resistivity, said film sections being disposed on and spaced apart from each other on each plate a distance substantially less than the width of a given secondary electron emissive film section, the positions of the film sections on one plate being staggered in the longitudinal direction from those on the other plate; a plurality of resistance elements made of a material having a substantially different resistivity than the secondaRy electron emissive material, said resistance elements being disposed in band-shaped patterns on the opposite surfaces of said plates from said emissive film sections, each band-shaped resistance element extending from one lateral side of the plate adjacent a first film section, to the laterally opposite side of said plate adjacent the next adjacent film section; means electrically coupling the respective ends of each resistance element to the corresponding adjacent emissive film section, said resistance elements and emissive film sections forming a series electrical circuit of alternating resistance elements and emissive film sections; a D.C. voltage source coupled across the series combination of said resistance elements and emissive film sections on each plate; and means for collecting the multiplied secondary electrons.

Claim 8

A channel-type secondary electron multiplier, comprising: a pair of parallel spaced flat plates of an electrically insulating material defining an electron multiplying channel therebetween; a plurality of secondary electron emissive film sections made of a secondary electron emissive material having a finite surface electrical resistivity, said film sections being disposed on and spaced apart from each other on each plate a distance substantially less than the width of a given secondary electron emissive film section, the positions of the film sections on one plate being staggered in the longitudinal direction from those on the other plate; a plurality of resistance elements made of a material having a substantially different resistivity than the secondaRy electron emissive material, said resistance elements being disposed in band-shaped patterns on the opposite surfaces of said plates from said emissive film sections, each band-shaped resistance element extending from one lateral side of the plate adjacent a first film section, to the laterally opposite side of said plate adjacent the next adjacent film section; means electrically coupling the respective ends of each resistance element to the corresponding adjacent emissive film section, said resistance elements and emissive film sections forming a series electrical circuit of alternating resistance elements and emissive film sections; a D.C. voltage source coupled across the series combination of said resistance elements and emissive film sections on each plate; and means for collecting the multiplied secondary electrons.