An optical spectral detection device utilizing free space optical beam propagation is provided. The device includes at least one optical fiber input, at least one opto-electronic detection device, an optical element having an actuator with at least one tilt axis, and a diffraction element having a surface thereon. The device also includes an optical beam transfer arrangement positioned between the optical element and the diffraction element such that tilt actuation of the optical element elicits a proportional change in an angle of incidence of the optical beam onto the diffraction element, wherein the center of rotation for the angular change is the surface of the diffraction element. The spectral properties of the optical beam that are detected are selected by selectively positioning the optical element about at least one of the tilt axes.