A bridge and roll method for doing an in-service switch from one set of inputs and outputs on a primary photonic switch to another set of inputs and outputs on the same or a secondary photonic switch. Floating gates are formed in each of the active regions by forming a conductive layer of material. By superposing on a part of the first layer, a second layer having the image of the painting or the photograph drawn on the exposed portion of the surface is provided. Clearances are formed between the projections and the ribs by recessing the inner surfaces of the ribs.