CIRCUIT BOARD CAPABLE OF SENSING LIGHT WITH OPEN HOLE AND MULTILAYER PRINTED CIRCUIT BOARD

The invention provides a circuit board capable of sensing light with an open hole. The circuit board comprises a layer of insulating layer, a layer of conductive layer, multiple conductors and a layer of covering layer. The covering layer comprises polyimide series light resistance. The insulating layer comprises multiple perforated faces which respectively define perforations. The conductive layer comprises a layer of first conductive layer with multiple through holes penetrating the lower surface from the upper surface. Parts of the through holes are communicated with parts of the perforations. Each of the conductors comprises a first surface and a second surface which are arranged on opposite sides. The first surfaces are respectively connected with the perforation faces. The covering layer covers the first conductive layer and completely covers the second surfaces of the conductors. The circuit board has high tenacity and favorable gas permeability, fits for current micro open holes and is simple and easy to prepare.