A collimator comprising a base, a plurality of side walls and an integral hinge coupled to at least one of the sidewalls to the base and tillable within a range of motion. The collimator is configured such that light emitted by the light source enters the collimator through a light entry opening and exits substantially only through a light exit opening for any position of the hinged side wall over its range of motion. A semiconductor light source may be arranged on a substrate, wherein the collimator encloses the semiconductor light source and an actuator moves the hinged side wall over at least part of its range of motion to adjust the light exit opening.