Automatic calibration of electron multiplying CCDs
AssigneeAndor Technology Limited
InventorDonal Denvir
Life of this patent
Estimating the term…
Abstract
A method of determining the gain of an electron multiplier, especially in an Electron Multiplying Charge Coupled Device (EMCCD). The electron multiplier multiplies, in use, signals received from a device, typically a CCD, comprising photodetectors. A test signal is input to the electron multiplier from the device, and the gain of the electron multiplier is determined from the output of the electron multiplier. The test signal comprises, or is derived from, electrical charge generated by the photodetectors other than as a result of the incidence of an electromagnetic signal on the photodetectors. The test signal comprises, or is derived from, dark current, or clock induced charge.
Claims24
A method of determining the gain of an electron multiplier, the electron multiplier being arranged to multiply, in use, signals received from a device comprising at least one photodetector, the method comprising causing a test signal to be input to the electron multiplier from the device;
- and determining the gain of the electron multiplier from the output of the electron multiplier, wherein said test signal comprises, or is derived from, electrical charge generated by said at least one photodetector other than as a result of the incidence of an electromagnetic signal on said at least one photodetector, and wherein said test signal comprises, or is derived from, dark charge or dark current.
A method of determining the gain of an electron multiplier, the electron multiplier being arranged to multiply, in use, signals received from a device comprising at least one photodetector, the method comprising causing a test signal to be input to the electron multiplier from the device;
- and determining the gain of the electron multiplier from the output of the electron multiplier, wherein said test signal comprises, or is derived from, electrical charge generated by said at least one photodetector other than as a result of the incidence of an electromagnetic signal on said at least one photodetector, and wherein said test signal comprises, or is derived from, clock induced charge, or spurious charge.
A method of determining the gain of an electron multiplier, the electron multiplier being arranged to multiply, in use, signals received from a device comprising at least one photodetector, the method comprising causing a test signal to be input to the electron multiplier from the device;
- and determining the gain of the electron multiplier from the output of the electron multiplier, wherein said test signal comprises, or is derived from, electrical charge generated by said at least one photodetector other than as a result of the incidence of an electromagnetic signal on said at least one photodetector, the method further including causing the test signal to be input to the electron multiplier when the gain of the electron multiplier is enabled, and when the gain of the electron multiplier is disabled;
- and determining the gain by comparing the output of the electron multiplier in response to said test signal when the gain of the electron multiplier is enabled to the output of the electron multiplier in response to said test signal when the gain of the electron multiplier is disabled.
A method of determining the gain of an electron multiplier, the electron multiplier being arranged to multiply, in use, signals received from a device comprising at least one photodetector, the method comprising causing a test signal to be input to the electron multiplier from the device;
- and determining the gain of the electron multiplier from the output of the electron multiplier, wherein said test signal comprises, or is derived from, electrical charge generated by said at least one photodetector other than as a result of the incidence of an electromagnetic signal on said at least one photodetector, the method further including determining the gain of the electron multiplier by analysing the characteristics of the output of the electron multiplier in response to said test signal when the gain of the electron multiplier is enabled.
An apparatus for detecting the gain of an electron multiplier, the apparatus comprising means for causing a test signal to be input to the electron multiplier from a device comprising at least one photodetector;
- and means for determining the gain of the electron multiplier from the output of the electron multiplier, wherein said test signal comprises, or is derived from, electrical charge generated by said at least one photodetector other than as a result of the incidence of an electromagnetic signal on said at least one photodetector, and wherein said test signal comprises, or is derived from, dark charge or dark current.
An apparatus for detecting the gain of an electron multiplier, the apparatus comprising means for causing a test signal to be input to the electron multiplier from a device comprising at least one photodetector;
- and means for determining the gain of the electron multiplier from the output of the electron multiplier, wherein said test signal comprises, or is derived from, electrical charge generated by said at least one photodetector other than as a result of the incidence of an electromagnetic signal on said at least one photodetector, and wherein said test signal comprises, or is derived from, clock induced charge, or spurious charge.
Dependencies are inferred from the claim text.