A method for making an optical structure and a multilayer optical structure provided with optical guide elements for transmitting at least a light wave, comprises: providing a substrate with a first and second layer; etching out in the second electrically conducting layer a groove having two opposite ends and partly enclosing a first zone of the layer; filling the groove with electrically insulating material; etching out a cavity in the second layer then in the first non-electrically conducting layer partly enclosing a second zone of the second layer, adjacent to or extending the first zone wherein emerges the groove; the cavity comprises a clearance in the second layer; such that the closed part of the second layer corresponding to the zones is electrically isolated from the rest of the layer and the cleared part beneath the second zone constitutes a beam.