An apparatus for providing modulated light, that includes: a VCSEL array for generating an illumination beam from a plurality of emissive elements within the VCSEL array; a linear array of electromechanical grating devices for modulating the illumination beam to provide a plurality of diffracted orders; an obstructing element for blocking at least one of the plurality of diffracted orders; and means for conditioning the illumination beam to provide a suitable aspect ratio for incidence onto the linear array of electromechanical grating devices and/or remove unwanted spatial content.