Low level radiation measurement device

Claim 1

A device for measuring low level environmental radiation, for example in the 0-200 μrem/h or equivalent range, comprising: a detector on which ionizing radiation can impinge, the detector, in response to impinging radiation events, providing a pulse signal indicative of said detected impinging events as a function of time and indicative of the energy of each of said detected impinging events, said pulse signal including a direct current noise component not caused by said impinging radiation events; and means for blocking said direct current noise component so as to filter from said pulse signal said direct current noise component, a remaining portion of said pulse signal indicating the average energy fluence of said detected impinging events as a function of time.

Claim 2

A device for measuring low level environmental radiation, for example in the 0-200 μrem/h or equivalent range, comprising: a detector on which ionizing radiation can impinge, the detector, in response to impinging radiation events, providing a pulse signal indicative of said detected impinging events as a function of time and indicative of the energy of each of said detected impinging events, said pulse signal including a direct current noise component not caused by said impinging radiation events; and means for blocking said direct current noise component so as to filter from said pulse signal said direct current noise component, a remaining portion of said pulse signal indicating the average energy fluence of said detected impinging events as a function of time.

Claim 4

A device of measuring low level environmental radiation, for example in the 0-200 μrem/h or equivalent range, comprising: a detector on which ionizing radiation can impinge, the detector, in response to impinging radiation events, providing a pulse signal indicative of said detected impinging events as a function of time and indicative of the energy of each of said detected impinging events, said pulse signal including a direct current noise component not caused by said impinging radiation events; and a capacitor for blocking said direct current noise component so as to filter from said pulse signal said direct current noise component, a remaining portion of said pulse signal being integrated to provide as a function of time a direct current signal indicative of the average energy fluence of said detected impinging events as a function of time.

Claim 5

A device of measuring low level environmental radiation, for example in the 0-200 μrem/h or equivalent range, comprising: a detector on which ionizing radiation can impinge, the detector, in response to impinging radiation events, providing a pulse signal indicative of said detected impinging events as a function of time and indicative of the energy of each of said detected impinging events, said pulse signal including a direct current noise component not caused by said impinging radiation events; and a capacitor for blocking said direct current noise component so as to filter from said pulse signal said direct current noise component, a remaining portion of said pulse signal being integrated to provide as a function of time a direct current signal indicative of the average energy fluence of said detected impinging events as a function of time.

Claim 7

A device for measuring low level environmental radiation, for example in the 0-200 μrem/h or equivalent range, comprising: a scintillator element on which ionizing radiation can impinge, the scintillator element, in response to impinging radiation events, generating light pulses indicative of said impinging events as a function of time and indicative of the energy of each of said impinging events; a photomultiplier tube optically coupled to said scintillator element so as to receive said light pulses, said photomultiplier tube, in response to said light pulses, providing a direct current pulse signal indicative of said detected impinging events as a function of time and indicative of the energy of each of said detected impinging events, said pulse signal including a "dark current" noise component not caused by said impinging radiation events; means for processing said pulse signal to provide a direct current signal whose amplitude is indicative of the average energy fluence of said detected impinging events as a function of time; and direct current blocking means electrically connected between said photomultiplier tube and said processing means, said blocking means filtering from said pulse signal said "dark current" component wherein only a remaining portion of said pulse signal is applied to said processing means.

Claim 8

A device for measuring low level environmental radiation, for example in the 0-200 μrem/h or equivalent range, comprising: a scintillator element on which ionizing radiation can impinge, the scintillator element, in response to impinging radiation events, generating light pulses indicative of said impinging events as a function of time and indicative of the energy of each of said impinging events; a photomultiplier tube optically coupled to said scintillator element so as to receive said light pulses, said photomultiplier tube, in response to said light pulses, providing a direct current pulse signal indicative of said detected impinging events as a function of time and indicative of the energy of each of said detected impinging events, said pulse signal including a "dark current" noise component not caused by said impinging radiation events; means for processing said pulse signal to provide a direct current signal whose amplitude is indicative of the average energy fluence of said detected impinging events as a function of time; and direct current blocking means electrically connected between said photomultiplier tube and said processing means, said blocking means filtering from said pulse signal said "dark current" component wherein only a remaining portion of said pulse signal is applied to said processing means.