Patent ID: 6831730
Filing Date: 2004-12-14
Classification: G03F,H05K

Abstract:
An optical projection exposure device for imprinting a circuit pattern on a printed circuit board, comprising:a photo mask having a prescribed pattern, projection means for projecting said photo mask pattern onto said board, a light source device for irradiating exposure rays through said projection means for imprinting said photo mask pattern on said board, and an optical magnification adjustment system installed in between said photo mask and said board for correcting the magnification of said pattern in at least one arbitrary direction, wherein: said optical magnification adjustment system has a first plano-convex or plano-concave lens with an optical power &PHgr;2, as defined by the equation below, and a second concave-plano or convex-plano lens with an optical power &PHgr;3, as defined by the equation below, both of which are installed in a telecentric position on the side of an object surface or on the side of an image in an optical exposure system, wherein the total system magnification of said optical exposure system may be minutely varied by changing the space between said lenses, &PHgr;3=âˆ’&PHgr;(S1e1)/d0 &PHgr;2=(&PHgr;âˆ’Ã˜3)/(1âˆ’d0Ã˜) where, &PHgr;: Total optical power of said optical magnification adjustment system, S1: Distance from the first surface of said first lens to said object surface, d0: Center space of said two lenses, that satisfies a magnification &bgr;=1, e1=t1/n1 (t1: Center thickness of said first lens 1, n1: Refraction index of said first lens 1).