Patent ID: 6070986
Filing Date: 2000-06-06
Classification: G01N,H05K

Abstract:
A method of manufacturing a lighting unit for inspecting a surface, the lighting unit having an opening at the center thereof for visually inspecting or taking photos of the surface to be inspected, wherein said method comprises the steps of:holding a flexible circular printed circuit board having a concentric circular hole and a cutout which has at least two sides in a planar state,embedding a plurality of illuminants in said printed circuit board,jointing one side of the cutout and the other side of the cutout of said printed circuit board or holding both sides in close contact so as to form the printed circuit board into a shape of a hollow truncated cone with the illuminants placed in a side of a concave face of said printed circuit board, andpositioning a frame about said printed circuit board and retaining said circuit board in said shape of a hollow truncated cone using said frame so as to obtain the lighting unit in which a plurality of illuminants are arranged on the concave face of the printed circuit board formed into the shape of a hollow truncated cone.