Method and apparatus for improving resolution in spectrometers processing output steps from non-ideal signal sources

A method for measuring the integrated area QgT of a pulse-like input signal applied to a device characterized by one or more decay time constants in said device's impulse response function by measuring a step-like output signal, referred to as the primary signal, provided by said device in response to said pulse-like input signal, the method comprising:

• creating a set of secondary signals by directing the primary signal into a plurality of signal paths connecting to one or more signal summation points;
• performing a filtering or delaying operation in at least one of said signal paths;
• applying a set of weighting coefficients to said secondary signals within said signal paths;
• summing said secondary signals at said one or more signal summation points to provide a time correlated, weighted filter sum signal;
• and
• performing at least one capturing operation after any filtering or delaying operations to produce a value of said time correlated, weighted filter sum signal, following said capturing and summing operations, that is a measure of said integrated area QgT of said input signal;
• wherein said filtering, delaying and/or capturing operations establish a defined time correlation between said secondary signals with respect to one another prior to reaching said one or more summation points;
• and
• wherein said weighting coefficients applied to the secondary signals are selected, based on the nature of any filters used in said filtering operations, on the defined time correlation established between said secondary signals, and on the values of the one or more decay time constants associated with said device, to compensate said measured area QgT for the risetime structure of said step-like pulse, for the presence of more than one decay time constant, or for both.

Apparatus for measuring the integrated area QgT of a pulse-like input signal applied to a device characterized by one or more decay time constants in said device's impulse response function by measuring a step-like output signal, referred to as the primary signal, provided by said device in response to said pulse-like input signal, the apparatus comprising:

• a plurality of signal paths that receive the primary signal, the signals traveling along said signal paths being referred to as secondary signals;
• at least one filter and/or delay element in at least one of said signal paths;
• weighting circuitry that performs a weighting function on said secondary signals within said signal paths;
• summing circuitry that sums said secondary signals to provide a time correlated, weighted filter sum signal;
• and
• capturing circuitry that captures said secondary signals after said secondary signals have encountered any filter or delay element in said signal paths to produce a value of said time correlated, weighted filter sum signal, following capturing and summing, that is a measure of said integrated area QgT of said input signal;
• wherein said at least one filter and/or delay element and/or said capturing circuitry establish a defined time correlation between said secondary signals with respect to one another prior to said secondary signals being summed;
• and
• wherein said weighting coefficients applied to the secondary signals are selected, based on the nature of any filters used in said signal paths, on the defined time correlation established between said secondary signals, and on the values of the one or more decay time constants associated with said device, to compensate said measured area QgT for the risetime structure of said step-like pulse, for the presence of more than one decay time constant, or for both.

A method for determining the integrated area QgT of a pulse-like input signal by measuring a step-like output signal provided by a device in response to said pulse-like input signal, the method comprising:

• applying a filter set having one or more filters to said device output;
• detecting the presence of a step-like feature in said output signal;
• in response to detecting said feature, capturing a set of correlated multiple output sample values (the area cMOS) from one or more filters in said filter set;
• and
• forming a weighted sum of the sample values in said area cMOS to determine said integrated area QgT (the determined area) of said input signal;
• wherein the weights in said sum (the area weights) are selected to compensate said determined area for errors arising either from the time structure of said pulse-like input, or from deviations in the device's response from an ideal single-pole response, or from both.

Apparatus for measuring a step-like output signal from a device in response to a pulse-like input signal to determine the integrated area QgT of said pulse-like input signal, the apparatus comprising:

• a set of one or more filters applied to the device output (the area filter set);
• circuitry that detects the presence of a step-like signal in said output signal;
• circuitry that captures a correlated multiple output sample (the area cMOS) from said area filter set in response to said detection event;
• circuitry that forms a weighted sum of the values in said area cMOS to determine said integrated area QgT (the determined area) of said pulse-like input signal;
• wherein the weights in said sum (the area weights) are selected to compensate said area determination for errors arising either from the time structure of said pulse-like input signal, or from deviations in the devices's response from an ideal single pole response, or from both.

A method for measuring the integrated area QgT of a pulse-like signal input to a device characterized by one or more decay time constants in its impulse response function by measuring a step-like pulse output signal, referred to as the primary signal, provided by said device in response to said pulse-like input signal, the method comprising:

• creating a set of secondary signals by directing the primary signal along a plurality of signal paths;
• performing a filtering or delaying operation in one or more of said signal paths so that the secondary signals reaching the ends of said signal paths have a defined time correlation with respect to one another;
• performing one or more capturing operations at the end of each of said signal paths to create a correlated multiple output sample (CMOS) set of secondary signal values;
• applying a set of weighting coefficients to said CMOS set of captured secondary signal values;
• summing said set of weighted CMOS values to provide a measure of said integrated area QgT of said input signal;
• wherein the weighting coefficients applied to said CMOS set of captured secondary signal values are selected, based on the nature of any filters used in said filtering operations, on any delays introduced in said delaying operations, and on the values of the one or more decay time constants associated with the device, to compensate said measured area for the risetime structure of said step-like pulse, for the presence of more than one decay time constant, or for both.