Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
194 words
An infra-red radiation imaging device arrangement comprising a plurality of infra-red radiation detector elements in which charge-signals are generated by incident infra-red radiation, and signal-processing circuitry for processing the charge-signals from the detector elements to provide an output signal representative of the radiation image incident on the detector elements, said circuitry including at least one charge-transfer line to which the radiation detector elements are coupled via input connections, each detector element being electrically connected between the input connection of the charge-transfer line and a second electrical connection of said plurality of detector elements, at least one storage electrode and at least one subtraction gate being present at each of the input connections for subtracting at least one portion of the charge-signal so that only a portion of the charge-signal from each detector element is transferred along the charge-transfer line, and means for draining away the subtracted charge from a storage well below the storage electrode, characterized in that the subtracted charge is drained away via the radiation detector elements by means of a voltage switching means which is connected to the second electrical connection to switch the voltage applied to the radiation detector elements.
Claim 2
Dependent Claim
194 words
An infra-red radiation imaging device arrangement comprising a plurality of infra-red radiation detector elements in which charge-signals are generated by incident infra-red radiation, and signal-processing circuitry for processing the charge-signals from the detector elements to provide an output signal representative of the radiation image incident on the detector elements, said circuitry including at least one charge-transfer line to which the radiation detector elements are coupled via input connections, each detector element being electrically connected between the input connection of the charge-transfer line and a second electrical connection of said plurality of detector elements, at least one storage electrode and at least one subtraction gate being present at each of the input connections for subtracting at least one portion of the charge-signal so that only a portion of the charge-signal from each detector element is transferred along the charge-transfer line, and means for draining away the subtracted charge from a storage well below the storage electrode, characterized in that the subtracted charge is drained away via the radiation detector elements by means of a voltage switching means which is connected to the second electrical connection to switch the voltage applied to the radiation detector elements.
Claim 3
Dependent Claim
22 words
An imaging device arrangement as claimed in claim 1, further characterized in that the voltage switching means is a voltage pulse generator.
Claim 4
Dependent Claim
39 words
An imaging device arrangement as claimed in claim 1, further characterized in that the voltage switching means and the at least one charge-transfer line are provided in a signal-processing circuit substrate to which the radiation detector elements are secured.
Claim 5
Dependent Claim
45 words
An imaging device arrangement as claimed in claim 1, further characterized in that the radiation detector elements are photodiodes formed in a common body or body portion of infra-red sensitive material, the bulk of which is a common region connected to the second electrical connection.
Claim 6
Dependent Claim
50 words
An imaging device arrangement as claimed in claim 1, further characterized in that the charge-transfer line is one of a plurality of parallel charge-transfer lines, and radiation detector elements which are arranged in a 2-dimensional array are connected to these lines via input connections at locations spaced along the lines.
Claim 7
Dependent Claim
34 words
An imaging device arrangement as claimed in claim 5, further characterized in that all the radiation detector elements of the array have a common second connection to which the voltage switching means is connected.
Claim 8
Dependent Claim
47 words
An imaging device arrangement as claimed in claim 5, further characterized in that at each of said locations each charge-transfer line has a clocking electrode which has a recess at one side, and an input gate and the input connection are located in each of said recesses.
Claim 9
Dependent Claim
23 words
An imaging device arrangement as claimed in claim 4, further characterized in that the radiation detector elements are photodiodes of cadmium mercury telluride.
Claim 10
Dependent Claim
41 words
An imaging device arrangement as claimed in claim 1, further characterized in that the at least one subtraction gate present at each of input connections comprises a threshold gate for subtracting a given background level from the charge-signal at that input.
Claim 11
Dependent Claim
31 words
An imaging device arrangement as claimed in claim 9, further characterized in that the threshold gate is formed by at least a portion of a clocking electrode of the charge-transfer line.
Claim 12
Dependent Claim
41 words
An imaging device arrangement as claimed in claim 1, further characterized in that the at least one subtraction gate present at each of the input connections comprises a partition gate for substracting a given fraction of the charge-signal at that input.