Dynamic Range Enhancement of Photodiode Array Spectra

The dynamic range of the photodiode array is typically 30 dB. In situations requiring a dynamic range greater than 30 dB, the photomultiplier tube is a popular alternative, but the advantage of multiwavelength simultaneous data acquisition—possible with a photodioide array—is lost. A method has been developed to enhance the dynamic range of spectra taken with the use of a photodiode array. A set of spectra is collected under computer control at varied integration times, and the optimum integration time is chosen individually for each detecting element. As a result, an improvement in the suppression of the noise floor is achieved, leading to a single spectrum with an enhanced dynamic range of 50 dB.