Methods of manufacturing optical devices are disclosed. The method includes providing a structure-forming fiber bonded to at least one other optical component, the structure-forming fiber having a preferentially-etchable portion including at least one radial etching boundary and at least one axial etching boundary, and etching the preferentially-etchable portion to the radial and axial etching boundaries to produce a precise optical structure. The preferentially-etchable portion may be removed through one or more radial openings in the structure-forming fiber. Numerous other aspects are provided.