A compact fiber variable optical attenuator (VOA) with <1-dB insertion loss and >25-dB dynamic range is proposed and demonstrated at the 1550-nm band using a fiber collimator lens and a bulk-micromachined cleformable micromirror. Three versatile VOA designs are presented that exploit the principle of 3-D beam spoiling to achieve broadband polarization insensitive attenuation using simple singledrive controls. (C) 2004 Society of Photo-Optical Instrumentation Engineers.A compact fiber variable optical attenuator (VOA) with <1-dB insertion loss and >25-dB dynamic range is proposed and demonstrated at the 1550-nm band using a fiber collimator lens and a bulk-micromachined cleformable micromirror. Three versatile VOA designs are presented that exploit the principle of 3-D beam spoiling to achieve broadband polarization insensitive attenuation using simple singledrive controls. (C) 2004 Society of Photo-Optical Instrumentation Engineers.