A method for manufacturing a collimating device is disclosed herein. In one embodiment the method includes a step of constructing a reflective layer. After the reflective layer is constructed, a step of constructing an optical element layer follows, including a step of forming an array of microstructures in the optical element layer. Next, the array of microstructures is abutted against the reflective layer. Heat and pressure are then applied to the optical element layer to puncture the reflective layer and penetrate a predetermined distance through the reflective layer. Sub-assemblies are also defined, wherein optical elements are coupled to prevent light loss.