Detection system for a flow cytometer
The detection system 10 of the first preferred embodiment is preferably designed to be integrated into a flow cytometer having an interrogation zone 12 . The detection system 10 includes a detector 14 adapted to receive photonic inputs P from the interrogation zone and produce an analog signal, and an analog-to-digital converter (ADC) 20 coupled to the detector and adapted to convert an analog signal to a digital signal. The detector 14 has a dynamic range that is preferably greater than or equal to 100 dB. The ADC 20 has a bit resolution that is preferably greater than or equal to 16 -bits. The detection system allows simultaneous collection of both small/faint objects and large/bright objects. In an application of this feature of the present invention, the detection system of the preferred embodiments may be used in the co-detection of mammalian cells and bacteria.
1 . A detection system for a flow cytometer having an interrogation zone, comprising:
a detector adapted to receive photonic inputs from the interrogation zone and produce an analog signal, the detector having a wide dynamic range; and
an analog-to-digital converter (ADC) coupled to the detector and adapted to convert an analog signal to a digital signal, the ADC having a high bit resolution.
2 . The detection system of claim 1 further comprising an amplifier coupled to the detector.
3 . The detection system of claim 2 wherein the amplifier is adapted to apply a dynamically variable gain to the analog signal.
4 . The detection system of claim 2 further comprising an automatic gain control unit coupled to an exciter and adapted to dynamically vary an excitation signal of the exciter.
5 . The detection system of claim 1 wherein the detector comprises a first detector and a second detector, wherein the first and second detectors operate on the same channel.
6 . The detection system of claim 5 wherein the first detector includes a first dynamic range and the second detector includes a second dynamic range, such that the first detector and the second detector cooperate as a detector having a wide dynamic range.
7 . The detection system of claim 5 further comprising a first amplifier coupled to the first detector, and a second amplifier coupled to the second detector.
8 . The detection system of claim 7 wherein the first amplifier includes a first gain and the second amplifier includes a second gain, and wherein the first and second gains are distinct.
9 . The detection system of claim 7 wherein the first and second amplifiers are adapted to apply a dynamically variable gain to the analog signals.
10 . The detection system of claim 7 further comprising an automatic gain control unit coupled to an exciter and adapted to dynamically vary an excitation signal of the exciter.
11 . The detection system of claim 1 further comprising a first amplifier and a second amplifier, wherein the detector is coupled to the first amplifier and to the second amplifier.
12 . The detection system of claim 11 wherein the first amplifier includes a first gain and the second amplifier includes a second gain, and wherein the first and second gains are distinct.
13 . The detection system of claim 11 wherein the first and second amplifiers are adapted to apply a dynamically variable gain to the analog signal.
14 . The detection system of claim 11 further comprising an automatic gain control unit coupled to an exciter and adapted to dynamically vary an excitation signal of the exciter.
15 . The detection system of claim 1 further comprising a synchronous detection unit.
16 . The detection system of claim 1 wherein the high bit resolution of the ADC is defined as greater than or equal to 16-bits.
17 . The detection system of claim 1 further comprising a signal compression unit adapted to compress and transmit signals to the ADC.
18 . The detection system of claim 1 wherein the detector is a photomultiplier.
19 . The detection system of claim 1 wherein the detector is a photodiode.
20 . The detection system of claim 1 wherein the wide dynamic range of the detector is defined as greater than or equal to 100 dB.