Axial trajectory sensor having gating means controlled by pulse duration measuring for electronic particle study apparatus and method

Claim 2

An axial trajectory sensor for use with a Coulter type particle analyzing apparatus in which particles passing through an aperture produce desirable particle pulses whose amplitudes are most nearly proportional to their respective sizes when passing closest to an axial trajectory through said aperture and having thereby a certain approximate duration and shape, and in which particles passing through said aperture on trajectories displaced from the axis will produce other particle pulses whose amplitudes are not necessarily proportional to their respective sizes and whose durations and shapes tend to depart from the duration and shape of said desirable particle pulses; said sensor acting to respond to desirable particle pulses and not to respond to said other pulses and comprising: A. input terminal means and output terminals means having a channel for passage of electrical signals between the terminal means with switch means in said channel to control the signals which appear at the output terminal means, the input terminal means adapted to have said desirable and other particle pulses applied thereto, B. means for measuring the duration of at least a portion of a particle pulse applied to said input terminal means at a plurality of different predetermined fractions of the amplitude thereof and deriving a plurality of duration-measuring pulses of constant amplitude and the duration-measuring pulses having the measured durations of the respective fractions, C. means for converting each said duration-measuring pulse into a respective electrical quantity whose value is proportional to the duration of the duration-measuring pulse from which it has been converted whereby to derive a plurality of electrical quantities, D. means establishing for each fraction an electrical effect of a band of values within which the value of an electrical quantity for a desirable pulse will fall for the particular fraction, and outside of which the value of an electrical quantity for one of said other pulses will fall for the particular fraction, E. means comparing the value of each quantity with said band of values for the respective fractions and producing one type of energizing signal if it falls within the band and a second type of energizing signal if it falls outside of the band, there being the same number of energizing signals as fractions, and F. means for applying all of the energizing signals to said switch means in said channel, the switch means being responsive to permit passage to said output terminal means of an electrical signal derived from a desirable pulse when all of the energizing signals are of the first type and said switch means being inactive and blocking any signals from passage to said output terminals means when any one of said energizing signals is of the second type.

Claim 3

The sensor as claimed in claim 1 in which said last-mentioned derived electrical signal comprises an output pulse of predetermined duration but having the amplitude of the desirable pulse.

Claim 4

The sensor as claimed in claim 1 in which the means for measuring dUration is operative to measure the duration of the entire particle pulse at each of said predetermined fractions.

Claim 5

The sensor as claimed in claim 1 in which said measuring means comprise circuitry to produce for each predetermined fraction an electric wave of a duration substantially longer than the duration at the respective fraction of the particle pulse from which the same is derived and each said electric wave having a constant amplitude over a substantial portion of its duration which amplitude is that of the particular predetermined fraction of the full amplitude of the particle pulse from which the same is derived, whereby to provide a plurality of said waves corresponding in number to the number of fractions and means for comparing said full particle pulse with said electrical waves during a period of time when all of the amplitudes of said waves are respectively constant.

Claim 6

The sensor as claimed in claim 4 in which said last-mentioned comparing means provide an output for each fraction only while said full particle pulse exceeds the amplitudes of the respective waves and said outputs being said duration-measuring pulses.

Claim 7

The sensor as claimed in claim 4 in which said circuitry includes a pulse stretcher and means for attenuating the output of the pulse stretcher amounts to provide said electric waves, one for each fraction.

Claim 8

The sensor as claimed in claim 6 in which said pulse stretcher is in said channel, produces as its output pulse a stretched wave having the amplitude of the particle pulse from which the same is derived and passes said stretched wave to said output terminal means only to the extent permitted by said switch means and without the intervention of said attenuating means.

Claim 9

The sensor as claimed in claim 1 in which said applying means include gating means between said comparing means and said switch means, means connected with said gating means are provided to produce a strobing pulse from said duration-measuring means to energize said gating means and operate said switch means to pass any signal or part thereof which exists in said channel for the duration only of said strobing pulse and in which said first type of energizing signal partially enables said gating means and said second type of energizing signal fully disables said gating means.

Claim 10

The axial trajectory sensor as claimed in claim 1 in which the electrical quantities into which said duration-measuring pulses are converted in each case comprises an electrical time signal pulse and the value of each said time signal pulse comprises its amplitude, in which the electrical effect for each fraction comprises a pair of voltage levels and the band of values comprise the voltages between the levels individual to each fraction, and in which the first-mentioned comparing means compare the time signal pulse of each fraction with the pair of voltage levels corresponding to that fraction to obtain the first type of energizing signal for any time signal pulse whose amplitude falls between the voltage levels corresponding to the same fraction and the second type of energizing signal for any time signal pulse whose amplitude falls outside of the voltage levels corresponding to the same fraction.

Claim 11

The sensor as claimed in claim 9 in which said electrical signals derived from desirable particle pulses comprise output pulses of predetermined duration but having respective amplitudes of said desirable particle pulses.

Claim 12

The sensor as claimed in claim 9 in which said means for measuring duration is operative to measure the duration of each of the fractions of the entire particle pulse at the respective fractional amplitude thereof.

Claim 13

The sensor as claimed in claim 9 in which said converting means comprise a plurality of integrators connected respectively to receive the measuring pulses, and the time signal pulses each comprise the output of an integrator in the form of a flat-topped pulse of the ramp and plateau type.

Claim 14

The sensor as claimed in clAim 9 in which said applying means include gating means between said comparing means and said switch means, means connected with said gating means are provided to produce a strobing pulse from said duration-measuring means to energize said gating means and operate said switch means to pass any signal or part thereof which exists in said channel for the duration only of said strobing pulse, in which said first type of energizing signal partially enables said gating means and said second type of energizing signal fully disables said gating means.

Claim 15

The sensor as claimed in claim 9 in which the means for establishing an electrical effect comprise means for producing voltage levels for each fraction which are respectively representative of the amplitudes of prior electrical time signals corresponding to that fraction and slight variations therefrom.

Claim 16

The sensor as claimed in claim 14 in which said means for producing voltage levels for each fraction comprise a memory circuit responsive to previously received electrical time signals and automatically maintaining a voltage output corresponding to some percentile of the amplitudes of said previously received electrical time signals, said voltage output comprising the first voltage level of each fraction, and means for modifying the said voltage output to produce the second voltage level, there being one such memory circuit for each said fractional amplitude.

Claim 17

The sensor as claimed in claim 15 in which the percentile is approximately 25 percent.

Claim 18

The sensor as claimed in claim 9 in which said measuring means comprise circuitry to produce for each predetermined fraction an electric wave of a duration substantially longer than the duration at the respective fraction of the particle pulse from which the same is derived and each said electric wave having a constant amplitude over a substantial portion of its duration which amplitude is that of the particular predetermined fraction of the full amplitude of the particle pulse from which the same is derived whereby to provide a plurality of said waves corresponding in number to the number of fractions and second comparing means for comparing said full particle pulse with said electrical waves during a period of time when all of the amplitudes of said waves are respectively constant.

Claim 19

The sensor as claimed in claim 17 in which said second comparing means provide an output for each fraction only while said full particle pulse exceeds the amplitudes of the respective waves and said outputs being said duration-measuring pulses.

Claim 20

The sensor as claimed in claim 17 in which said circuitry includes a pulse stretcher and means for attenuating the output of the pulse stretcher an amount to provide said electric waves, one for each fraction.

Claim 21

The sensor as claimed in claim 19 in which said pulse stretcher is in said channel and passes an electric wave of the same amplitude as that of the particle pulse to said output terminal means only to the extent permitted by said switch means.

Claim 22

An axial trajectory sensor for use with a Coulter type particle analyzing apparatus in which particles passing through an aperture produce desirable particle pulses whose amplitudes are most nearly proportional to their respective sizes when passing closest to an axial trajectory through the aperture and having thereby a certain approximate duration and shape and in which particles passing through said aperture on trajectories displaced from the axis will produce other particle pulses whose amplitudes are not necessarily proportional to their respective sizes and whose durations and shapes tend to depart from said certain approximate duration and/or shape; said sensor acting to respond to desirable particle pulses and not to respond to said other particle pulses and comprising: A. input terminal means and output terminal means having a channel for passage of electrical signals between the terminal means with switch means in said channel to control the siGnals which appear at the output terminal means, the input terminal means adapted to have said desirable and other particle pulses applied thereto, B. means for measuring the duration of a particle pulse applied to said input terminal means at a plurality of different predetermined fractions of the amplitude of said full particle pulse and deriving a plurality of duration-measuring pulses of constant amplitude and each having the measured duration at the respective fraction, C. means for converting each of said duration-measuring pulses into a respective time signal pulse whose amplitude is proportional to the duration of the duration-measuring pulse from which it has been converted whereby to derive a plurality of time signal pulses of different amplitudes corresponding in number to the number of fractions, D. means establishing for each fraction a voltage level corresponding to the maximum amplitude for a time signal pulse representing maximum duration for a desirable pulse measured at the particular fraction, all time signal pulses of amplitude greater than said voltage level being those corresponding to said other pulses, E. means comparing each said level with the time signal pulse corresponding to the same fraction individual to the level and producing one type of energizing signal for each time signal pulse that does not exceed its level and a second type of energizing signal for each time signal pulse that exceeds its level, there being as many energizing signals as fractions, and F. means for applying all of said energizing signals to said switch means in said channel, the switch means being responsive to permit passage to said output terminal means of an electrical signal derived from a desirable pulse when all of the energizing signals are of the first type, but said switch means being non-responsive and blocking any signals from passage to said output terminal means when any one of said energizing signals is of the second type.

Claim 23

An axial trajectory sensor for use with a Coulter type particle analyzing apparatus in which particles passing through an aperture produce desirable particle pulses whose amplitudes are most nearly proportional to their respective sizes when passing closest to an axial trajectory through the aperture and having thereby a certain approximate duration and shape and in which particles passing through said aperture on trajectories displaced from the axis will produce other particle pulses whose amplitudes are not necessarily proportional to their respective sizes and whose durations and shapes tend to depart from said certain approximate duration and/or shape; said sensor acting to respond to desirable particle pulses and not to respond to said other particle pulses and comprising: A. input terminal means and output terminal means having a channel for passage of electrical signals between the terminal means with switch means in said channel to control the siGnals which appear at the output terminal means, the input terminal means adapted to have said desirable and other particle pulses applied thereto, B. means for measuring the duration of a particle pulse applied to said input terminal means at a plurality of different predetermined fractions of the amplitude of said full particle pulse and deriving a plurality of duration-measuring pulses of constant amplitude and each having the measured duration at the respective fraction, C. means for converting each of said duration-measuring pulses into a respective time signal pulse whose amplitude is proportional to the duration of the duration-measuring pulse from which it has been converted whereby to derive a plurality of time signal pulses of different amplitudes corresponding in number to the number of fractions, D. means establishing for each fraction a voltage level corresponding to the maximum amplitude for a time signal pulse representing maximum duration for a desirable pulse measured at the particular fraction, all time signal pulses of amplitude greater than said voltage level being those corresponding to said other pulses, E. means comparing each said level with the time signal pulse corresponding to the same fraction individual to the level and producing one type of energizing signal for each time signal pulse that does not exceed its level and a second type of energizing signal for each time signal pulse that exceeds its level, there being as many energizing signals as fractions, and F. means for applying all of said energizing signals to said switch means in said channel, the switch means being responsive to permit passage to said output terminal means of an electrical signal derived from a desirable pulse when all of the energizing signals are of the first type, but said switch means being non-responsive and blocking any signals from passage to said output terminal means when any one of said energizing signals is of the second type.

Claim 24

The sensor as claimed in claim 21 in which said electrical signals derived from desirable particle pulses comprise output pulses of predetermined duration but having the respective amplitudes of desirable particle pulses.

Claim 25

The sensor as claimed in claim 22 in which said measuring means comprise circuitry to produce for each predetermined fraction an electric wave of a duration substantially longer than the duration at the respective fraction of the particle pulse from which the same is derived and each of said electric wave having a constant amplitude over a substantial portion of its duration which amplitude is that of the particle pulse from which the same is derived, whereby to provide a plurality of said electric waves corresponding in number to the number of fractions and second comparing means for comparing the full particle pulse with said electric waves during a period of time when all of the amplitudes of said waves are respectively constant.

Claim 26

The sensor as claimed in claim 23 in which said second comparing means provide an output for each fraction only while said full particle pulse exceeds the amplitudes of the respective electrical waves and said outputs being said duration-measuring pulses.

Claim 27

The sensor as claimed in claim 23 in which said circuitry includes a pulse stretcher and means for attenuating the output of the pulse stretcher an amount to provide said electric waves, one for each fraction.

Claim 28

The sensor as claimed in claim 25 in which said pulse stretcher provides an unattentuated electric wave in said channel of the same amplitude as that of the particle pulse which has been stretched, said last-mentioned electric wave being applied to said output terminal means only to the extent permitted by said switch means.

Claim 29

The sensor as claimed in claim 21 in which the means for establishing a voltage level comprise a circuit connected to receive the electrical time signals as its input and having said voltage level as its output, said voltage lEvel being representative of the amplitudes of prior electrical time signals received by said circuit.

Claim 30

The sensor as claimed in claim 27 in which said circuit comprises a memory circuit automatically maintaining a voltage output corresponding to some percentile of the amplitudes of said previously received electrical time signals.

Claim 31

The sensor as claimed in claim 28 in which said percentile is approximately 25 percent.

Claim 32

The sensor as claimed in claim 29 in which said converting means comprise a plurality of integrators connected respectively to receive the duration-measuring pulses, and the time signal pulses each comprise the output of an integrator in the form of a flat-topped pulse of the ramp and plateau type.

Claim 33

The sensor as claimed in claim 22 in which said applying means include gating means between said comparing means and said switch means, means connected with said gating means are provided to produce a strobing pulse from said duration-measuring means to energize said gating means and operate said switch means to pass any signal or part thereof which exists in said channel for the duration only of said strobing pulse, in which said first type of energizing signal partially enables said gating means and said second type of energizing signal fully disables said gating means.

Claim 34

The sensor as claimed in claim 22 in which means are provided for establishing for each fraction a second voltage level corresponding to the minimum amplitude for a time signal pulse, representing minimum duration for a desirable pulse measured at the particular fraction, all time signal pulses of amplitude less than said second voltage level being those corresponding to said other pulses, said comparing means also compares each time signal pulse corresponding to the same fraction individual to the second level and producing a third type of energizing signal for each time signal pulses that is above its second level and a fourth type of energizing signal for each time signal pulse that is below its second level, there being two energizing signals for each fraction, and said switch means being responsive to permit passage to said output terminal means of an electrical signal derived from a desirable pulse when all of the energizing signals resulting from comparison with said second level are of the third type in addition to the previously mentioned energizing signals being of said first type, and blocking any signals from passage to said output terminal means when any one of said energizing signals is of the fourth type or second type.

Claim 35

The sensor as claimed in claim 32 in which said comparing means comprising a pair of comparators for each fraction, one of each pair being connected to compare the time signal pulse corresponding to a fraction with the first voltage level and its output comprising either a first or a second type of energizing signal, and the other of each pair being connected to compare the time signal corresponding to the same fraction with the second voltage level and its output comprising either a third or a fourth type of energizing signal.

Claim 36

The sensor as claimed in claim 32 in which said applying means include gating means provided between said comparing means and said switch means, means connected with said gating means are provided to produce a strobing pulse from said duration-measuring means to energize said gating means and operate said switch means to pass any signal or part thereof which exists in said channel for the duration only of said strobing pulse, in which said first and third types of energizing signal each partially enables said gating means and any one of said second and fourth types of energizing signal fully disables said gating means.

Claim 37

The sensor as claimed in claim 34 in which said gating means comprise a plurality of two-input AND gates, there being one gate for each fraction and each gate being connected to said comparing means to receive either a first or second type of energizing signal On one input and either a third or fourth type of energizing signal on the second input, all of the energizing signals received by each gate being related to the fractional amplitude individual to that gate, and there being as many gates as fractions, and a multiple input AND gate having the outputs of the two-input AND gates connected thereto, the latter AND gate having one more input than the number of two-input AND gates, the strobing pulse producing means being connected also to an input of said multiple input AND gate, the output of said multiple input AND gate being connected to said switch means.

Claim 38

The sensor as claimed in claim 35 in which there is a resettable flip-flop between the output of said multiple input AND gate and said switch means adapted to be set by the output of said last-mentioned gate, and means are provided to reset said flip-flop after any particle pulse has been processed by said sensor.

Claim 39

The sensor as claimed in claim 32 in which the means for establishing the first voltage level comprise a circuit connected to receive the electrical time signals as its input and having said voltage level as its output, said voltage level being representative of the amplitudes of prior electrical time signals received by said circuit, and in which the means are provided modifying the output of said circuit to provide said second voltage level, there being one such memory circuit for each fractional amplitude.

Claim 40

The sensor as claimed in claim 37 in which said circuit comprises a memory circuit automatically maintaining a voltage output corresponding to some percentile of the amplitudes of said previously received electrical time signals.

Claim 41

The sensor as claimed in claim 38 in which said percentile is approximately 25 percent.

Claim 44

The method as claimed in claim 40 in which previously received electrical time signal pulses are received for each fractional amplitude and a predetermined percentile sensed to produce the said signal level for each fractional amplitude.

Claim 45

The method as claimed in claim 41 in which said percentile is 25 percent.

Claim 46

The method as claimed in claim 41 in which the addition, each signal level is modified to provide a second signal level below the first, each electrical time signal pulse producing a third type of energizing signal if it is above the second level and a fourth type of energizing signal if it is below the second level, and in which the electrical signal derived from the whole particle pulse is passed if all of the energizing sigNals produced by the plurality of electrical time signal pulses are of the first and third type but blocked if any one is of the second or fourth type.

Claim 47

The method as claimed in claim 40 in which said percentile is 25 percent.

Claim 48

An axial trajectory sensor for use with a Coulter type particle analyzing device, comprising: A. means for measuring the duration of each particle pulse produced by the analyzing device at a plurality of different predetermined fractional amplitudes, B. means for comparing each such measurement with a standard established for each fractional amplitude, and C means for rejecting all particle pulses, all of whose measurements at said fractional amplitudes do not meet said standards.

Claim 49

An axial trajectory sensor for use with a Coulter type particle analyzing device, comprising: A. means for measuring the duration of each particle pulse produced by the analyzing device at a plurality of different predetermined fractional amplitudes, B. means for comparing each such measurement with a standard established for each fractional amplitude, and C means for rejecting all particle pulses, all of whose measurements at said fractional amplitudes do not meet said standards.

Claim 50

The sensor as claimed in claim 45 in which means are provided for establishing said standard on the basis of the measurement of the durations of previous particle pulses made at the particular fractional amplitude.