An optical grid structure, method for producing the optical grid structure, an evanescence field sensor plate, a microtitre plate

Production of a grid structure comprises covering a surface section of a substrate with a photo lacquer layer (10); arranging the surface section in the near field of a phase mask (14) which has been structured according to a laser two beam interference method; irradiating the phase mask under the Littrow angle (theta L) or not more than 5 [deg]; developing the lacquer; etching the surface section to form the grid structure and removing the photo lacquer layer. Preferred Features: The phase mask is a transparent substrate and comprises a structured layer which the grid structure optically inactivates. The structured layer is made of a chrome layer.