US 5,637,959 A · Position sensitive photomultiplier

Abstract

This invention relates to a photomultiplier for detecting the incident position of a plane of incidence, where a weak light beam is reached and to a photomultiplier having a structure for minimizing crosstalk near the incident position of the weak light beam to improve the precision of the position resolving power. Particularly, the anode of this photomultiplier, which extracts the incident position of the incident weak light as an electrical signal, is constituted by a first anode component for detecting the incident position of the incident plane in the X direction and a second anode component for detecting the incident position of the incident plane in the Y direction. The first and second anode components have flat surfaces. These flat surfaces cause the first and second anode components to capture secondary electrons emitted from a dynode in correspondence with the incident position of the weak light beam, at a position closer to the emission position. The photomultiplier detects the incident position of the weak light beam at a higher resolving power while minimizing the crosstalk.

Claims23

Dependent claims

A photomultiplier comprising:

a photocathode for emitting photoelectrons corresponding to an incident weak light beam;
a dynode unit, constituted by stacking a plurality of dynodes, for multiplying the photoelectrons emitted from said photocathode;
and
an anode provided between said dynode unit and a bottom portion of said photomultiplier, for detecting an incident position of an incident plane where the weak light beam is reached, said anode having a first anode component for detecting the incident position of the incident plane in a first direction and a second anode component for detecting the incident position of the incident plane in a second direction perpendicular to the first direction, wherein
said first anode component has a plurality of through holes for passing at least some of the secondary electrons emitted from said dynode unit, a first flat surface opposing said dynode unit, and a second flat surface on opposite side of said first surface, and said second anode component has a first flat surface opposing said second surface of said first anode component and a second flat surface on opposite side of said first surface of said second anode component.

2 more elements

A photomultiplier comprising:

a photocathode for emitting photoelectrons corresponding to an incident weak light beam;
a dynode unit, arranged between said photocathode and a bottom portion of said photomultiplier, for multiplying the photoelectrons emitted from said photocathode, said dynode unit being constituted by stacking a plurality of dynode plates, each of which supports at least one dynode, along an incident direction of the photoelectrons;
an anode for detecting an incident position of an incident plane where the weak light beam is reached, said anode being provided between said dynode unit and said bottom portion of said photomultiplier, set at a potential higher than that of any one of said dynode plates, and having a first anode component for detecting the incident position of the incident plane in a first direction and a second anode component for detecting the incident position of the incident plane in a second direction perpendicular to the first direction, said first anode component having through holes for passing secondary electrons multiplied by said dynode unit, a first surface opposing said dynode unit, and a second flat surface on an opposite side of said first surface, and said second anode component being arranged between said first anode component and said bottom portion of said photomultiplier at a position separated from said first anode component by a predetermined interval, having through holes for passing the secondary electrons passing through said first anode component, a first surface opposing said second surface of said first anode component, and a second flat surface on an opposite side of said first surface of said second anode component;
and
an inverting dynode, arranged between said anode and said bottom portion of said photomultiplier and set at a potential lower than that of said anode, for receiving the secondary electrons passing through the through holes of said anode and emitting the secondary electrons toward said anode.

2 more elements

An anode, applied to a photomultiplier for receiving an incident weak light beam and extracting an electrical signal corresponding to the weak light beam, for detecting an incident position of an incident plane where the weak light beam is reached, comprising:

a first anode component for detecting the incident position of the incident plane in a first direction, said first anode component having a plurality of metal plates aligned in a first direction at a predetermined interval and extending in a second direction perpendicular to the first direction, each of said metal plates having a flat surface along the second direction and a plurality of through holes arranged in a line in the second direction;
a second anode component for detecting the incident position of the incident plane in the second direction, said second anode component having a plurality of metal plates aligned in the second direction at a predetermined interval and extending in the first direction, each of said metal plates having a flat surface along the first direction and a plurality of through holes arranged in a line in the first direction;
and
an insulating member, provided between said first anode component and said second anode component, for separating said first anode component from said second anode component by a predetermined distance, said first anode component and said second anode component being set at an equal potential.

1 more element

a first anode component for detecting the incident position of the incident plane in a first direction, said first anode component having a first insulating plate having a plurality of through holes, and a plurality of first conductive thin films disposed on a surface of said first insulating plate, extending in a second direction perpendicular to the first direction, and aligned in the first direction at a predetermined interval,
a second anode component for detecting the incident position of the incident plane in the second direction, said second anode component having a second insulating plate having a plurality of through holes, and a plurality of second conductive thin films formed on a surface of said second insulating plate, extending in the first direction, and aligned in the second direction at a predetermined interval;
and
an insulating member, provided between said first anode component and said second anode component, for separating said first anode component from said second anode component by a predetermined distance, said first anode component and said second anode component being set at an equal potential.

1 more element

Dependencies are inferred from the claim text.

Position sensitive photomultiplier

Life of this patent

Position sensitive photomultiplier

Life of this patent

Abstract

Claims23