Patent ID: 8718948

Claim:
A method for detecting multiple different optical signals emitted from the contents of each of two or more receptacles, each different optical signal indicating the presence of a different analyte of interest or amplification products thereof, said method comprising: (a) forming amplification products of an analyte of interest within each receptacle; (b) generating an excitation signal that has a predetermined excitation wavelength that excites an emission moiety which emits an emission signal that is associated with the excitation wavelength and that is modulated at a predetermined excitation frequency; (c) while forming the amplification products, directing the excitation signal at the contents of each receptacle; (d) with a signal detecting device, detecting an optical signal including an emission signal emitted from each receptacle and generating detection data from the detected signal; (e) digitizing the detection data using a computer-implemented signal-digitizing algorithm; (f) determining the amplitude of the detection data that is at the predetermined excitation frequency by mathematically processing the digitized detection data using a computer-implemented digital signal processing technique for determining the amplitude of the detection data at the predetermined excitation frequency to thereby ascertain the portion of the detected signal that corresponds to the associated emission signal; and (g) repeating steps (b)-(f) for each of the multiple different optical signals to be detected, wherein the predetermined excitation frequency for an excitation signal associated with the emission signal of one emission moiety is different from the predetermined excitation frequency for at least one other emission moiety in the receptacle.