Abstract: An apparatus and method for minimizing the amplitude range in a time domain signal incorporating a plurality of periodic electromagnetic waves. One embodiment of the invention is a spectrophotometer or polychromatic light transmitter including an array of light emitting diodes or lasers configured for activation in successive encodement patterns, a diffraction grating, an optical slit, a detector and electronic controls including a computer. In operation, the periodic waves driving the diodes or lasers and their phases are adjusted in accordance with Hadamard mathematics in order to minimize constructive and destructive interference between the electromagnetic waves generated by the diodes array. The resulting time domain signal received at the detector is Fourier transformed to the desired spectral space. The invention effectively eliminates centerbursts in the resulting interferogram.

Abstract: A spectrophotometer includes an array of light emitting diodes configured for activation in successive Hadamard encodement patterns, a diffraction grating, an optical slit, a detector and electronic controls including a computer. In operation, the diffraction grating disperses and collimates radiation from the array and directs selected spectral components through the slit onto the detector whereupon the computer performs a Hadamard analysis on the detector signals.