Using a simplified fabrication process, we present the experimental verification of the performance of a 3-D photonic crystal optical transmission filter. Inherent to this unique fabrication approach to the realization of narrow line width, highly efficient optical transmission filters, is the ability to spatially vary the transmission characteristics across the filter aperture. This differentiates this type of filter from conventional dielectric based space variant optical transmission filters which require additional processing at intermediate steps within the dielectric film deposition process. The multilayer stack consists of alternating high and low refractive index dielectric material grown on either side of a high index dielectric spacer layer, which produces a narrow transmission notch in the center of a large stop band. The nano-structuring of a square lattice array of holes and subsequent etching of the pattern through a dielectric stack provides the ability to spatially vary the location of the narrow transmission peak within the wide stop band based off of variation of the hole diameter or lattice constant of the array.© (2007) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.