Imaging dynodes arrangement

Claim 2

An imaging dynodes arrangement for an electron multiplier, comprising: (a) a first imaging dynode having a first set of dynode cones with a cone tip and a cone base, the dynode cones of the first set being connected with each other such that they form free cavities therebetween; (b) a second imaging dynode having a second set of dynode cones with a cone tip and a cone base, the dynode cones of the second set being connected with each other such that they form free cavities therebetween; and (c) needle-shaped extraction points arranged at the cone tips of at least the dynode cones of the second set; wherein the second imaging dynode is mounted beneath the first imaging dynode in a staggered position such that the cone tips of the dynode cones of the second set are seated beneath the cavities of the first imaging dynode, directing the needle-shaped extraction points towards the cavities.

Claim 3

The dynodes arrangement according to claim 1, wherein the needle-shaped extraction points protrude into the cavities.

Claim 4

The dynodes arrangement according to claim 1, wherein one needle-shaped extraction point is arranged at each cone tip of the dynode cones of the second set.

Claim 5

The dynodes arrangement according to claim 3, wherein each cone tip comprises a flat area and wherein the corresponding needle-shaped extraction poit is positioned in the middle of the flat area.

Claim 6

The dynodes arrangement according to claim 1, comprising an additional number of imaging dynodes, each having dynode cones with a cone tip and a cone base and each incorporating a needle-shaped extraction point on the tip of each dynode cone, wherein all additional imaging dynodes are arranged in a pattern one beneath the other and beneath the second dynode in staggered positions such that the needle-shaped extraction points of an imaging dynode are seated beneath to the cavities of the overlying imaging dynode.

Claim 7

A photomultiplier tube, comprising: (a) a photocathode; (b) an anode; and (c) an imaging dynodes arrangement between the photocathode and the anode including (c1) a first imaging dynode having a first set of dynode cones with a cone tip and a cone base, the dynode cones of the first set being connected with each other such that they form free cavities therebetween; (c2) a second imaging dynode having a second set of dynode cones with a cone tip and a cone base, the dynode cones of the second set being connected with each other such that they form free cavities therebetween; and (c3) needle-shaped extraction points arranged at the cone tips of at least the dynode cones of the second set; wherein the second imaging dynode is mounted beneath the first imaging dynode in a staggered position such that the cone tips of the dynode cones of the second set are seated beneath the cavities of the first imaging dynode, directing the needle-shaped extraction points towards the cavities.

Claim 8

A photomultiplier tube, comprising: (a) a photocathode; (b) an anode; and (c) an imaging dynodes arrangement between the photocathode and the anode including (c1) a first imaging dynode having a first set of dynode cones with a cone tip and a cone base, the dynode cones of the first set being connected with each other such that they form free cavities therebetween; (c2) a second imaging dynode having a second set of dynode cones with a cone tip and a cone base, the dynode cones of the second set being connected with each other such that they form free cavities therebetween; and (c3) needle-shaped extraction points arranged at the cone tips of at least the dynode cones of the second set; wherein the second imaging dynode is mounted beneath the first imaging dynode in a staggered position such that the cone tips of the dynode cones of the second set are seated beneath the cavities of the first imaging dynode, directing the needle-shaped extraction points towards the cavities.

Claim 9

A scintillatoin gamma camera, comprising: (a) a scintillation crystal; (b) a number of photomultiplier tubes mounted behind the scintillation crystal, wherein each photomultiplier tube having (b1) a photocathode; (b2) an anode; and (b3) an imaging dynodes arrangement between the photocathode and the anode including (b31) a first imaging dynode having a first set of dynode cones with a cone tip and a cone base, the dynode cones of the first set being connected with each other such that they form free cavities therebetween; (b32) a second imaging dynode having a second set of dynode cones with a cone tip and a cone base, the dynode cones of the second set being connected with each other such that they form free cavities therebetween; and (b33) needle-shaped extraction points arranged at the cone tips of at least the dynode cones of the second set; wherein the second imaging dynode is mounted beneath the first imaging dynode in a staggered position such that the cone tips of the dynode cones of the second set are seated beneath the cavities of the first imaging dynode, directing the needle-shaped extraction points towards the cavities.

Claim 10

A scintillatoin gamma camera, comprising: (a) a scintillation crystal; (b) a number of photomultiplier tubes mounted behind the scintillation crystal, wherein each photomultiplier tube having (b1) a photocathode; (b2) an anode; and (b3) an imaging dynodes arrangement between the photocathode and the anode including (b31) a first imaging dynode having a first set of dynode cones with a cone tip and a cone base, the dynode cones of the first set being connected with each other such that they form free cavities therebetween; (b32) a second imaging dynode having a second set of dynode cones with a cone tip and a cone base, the dynode cones of the second set being connected with each other such that they form free cavities therebetween; and (b33) needle-shaped extraction points arranged at the cone tips of at least the dynode cones of the second set; wherein the second imaging dynode is mounted beneath the first imaging dynode in a staggered position such that the cone tips of the dynode cones of the second set are seated beneath the cavities of the first imaging dynode, directing the needle-shaped extraction points towards the cavities.

Claim 11

A single tube scintillation gamma camera comprising: (a) a scintillation crystal; (b) a photocathode associated with the scintillation crystal; (c) an anode; and (d) an imaging dynodes arrangement between the photocathode and the anode including (d1) a first imaging dynode having a first set of dynode cones with a cone tip and a cone base, the dynode cones of the first set being connected with each other such that they form free cavities therebetween; (d2) a second imaging dynode having a second set of dynode cones with a cone tip and a cone base, the dynode cones of the second set being connected with each other such that they form free cavities therebetween; and (d3) needle-shaped extraction points arranged at the cone tips of a least the dynode cones of the second set; wherein the second imaging dynode is mounted beneath the first imaging dynode in a staggered position such that the cone tips of the dynode cones of the second set are seated beneath the cavities of the first imaging dynode, directing the needle-shaped extraction points towards the cavities.

Claim 12

A single tube scintillation gamma camera comprising: (a) a scintillation crystal; (b) a photocathode associated with the scintillation crystal; (c) an anode; and (d) an imaging dynodes arrangement between the photocathode and the anode including (d1) a first imaging dynode having a first set of dynode cones with a cone tip and a cone base, the dynode cones of the first set being connected with each other such that they form free cavities therebetween; (d2) a second imaging dynode having a second set of dynode cones with a cone tip and a cone base, the dynode cones of the second set being connected with each other such that they form free cavities therebetween; and (d3) needle-shaped extraction points arranged at the cone tips of a least the dynode cones of the second set; wherein the second imaging dynode is mounted beneath the first imaging dynode in a staggered position such that the cone tips of the dynode cones of the second set are seated beneath the cavities of the first imaging dynode, directing the needle-shaped extraction points towards the cavities.