Unique multi-
diffraction structures using electronically controlled Bragg 
diffraction devices such as acousto-optic (AO) devices to accomplish 
optical beam attenuation control functions. These variable 
optical attenuator (VOA) modules can be fully inertialess as they can use electronically programmable sub-
microsecond speed AO devices to implement optical 
gain controls. These VOAs deliver desirable capabilities in one optically reversible unit, making 
high dynamic range, low loss, high 
power handling, ultra-fast, high optical isolation, 
broadband operation, self-aligning robust modules. These VOAs can be made essentially independent of the 
optical polarization of the incident light by the use of a unique fixed 
waveplate compensation technique within the VOA configuration that suppresses 
polarization dependent loss. 
Broadband gain control operation over several wavelengths can be achieved by controlling the frequency and 
electrical drive power of the chosen frequencies feeding the acousto-optic devices. Interleaver devices can be cascaded with the acousto-optic modules to improve 
wavelength selectivity of the overall VOA modules. Alternative embodiments can use electrically programmable Bragg gratings in 
polymer dispersed 
liquid crystal and acousto-optic tunable filter devices as Bragg 
grating devices. Embodiments are proposed using independently controlled Bragg diffractions using multiple drive signals connected to 
multiple device transducers. Drive 
signal formats can be digital, analog, or a combination for simultaneously driving the VOA modules. Dual-mode VOA module designs are also described using mirror positioning.