According to one embodiment of the present invention, a system for encoding an optical spectrum includes a dispersive element, a digital micromirror device (DMD) array, a detector, and a controller. The dispersive element receives light from a source and disperses the light to yield light components of different wavelengths. The digital micromirror device (DMD) array has micromirrors that modulate the light to encode an optical spectrum of the light. The detector detects the light that has been modulated. The controller generates an intensity versus time waveform representing the optical spectrum of the detected light.