Patent ID: 8229062
Filing Date: 2012-07-24
Classification: G03F

Abstract:
1. An imaging system comprising: a radiation source; a radiation sensitive material; an exposure mask disposed between the radiation source and the radiation sensitive material, the exposure mask having radiation reflective or absorbing areas and radiation-transmissive openings, the exposure mask for exposing the radiation sensitive material only to radiation which passes through the radiation-transmissive openings, the exposure mask having a first area wherein some of the radiation transmissive openings are distributed in a first density, and having a second area wherein some of the radiation-transmissive openings are distributed in a second density which differs from the first density; a differential attenuator integral to the exposure mask and cooperable with the radiation-transmissive openings, the differential attenuator for attenuating radiation passing through the radiation transmissive openings of the first area by a first amount of attenuation; and the differential attenuator for attenuating radiation passing through the radiation-transmissive openings in the second area by a second amount of attenuation that differs from the first amount of attenuation, wherein the differential attenuator includes first and second portions of a single layer of partial light shielding material overlying and secured to a transport support glass, the first amount of attenuation corresponding to a thickness of the differential attenuator in the first area from the support glass and the second amount of attenuation corresponding to a thickness of the differential attenuator in the second area from the support glass, where the thickness of the differential attenuator in the first area differs from the thickness of the differential attenuator in the second area.