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We present here new experimental results on high contrast imaging of 10^{-7}at 4.5Lambda/D (Lambda = 0.820 microns) by combining a circular focal planemask (coronagraph) of 2.5Lambda/D diameter and a multi-Gaussian pupil planemask. Both the masks were fabricated on very high surface quality (Lambda/30)BK7 optical substrates using nano-fabrication techniques of photolithographyand metal lift-off. This process ensured that the shaped masks have a useableedge roughness better than Lambda/4 (rms error better than 0.2 microns), aspecification that is necessary to realize the predicted theoretical limits ofany mask design. Though a theoretical model predicts a contrast level of10^{-12}, the background noise of the observed images was speckle dominatedwhich reduced the contrast level to 4x10^{-7} at 4.5Lambda/D. The optical setupwas built on the University of Illinois Seeing Improvement System (UnISIS)optics table which is at the Coude focus of the 2.5-m telescope of the Mt.Wilson Observatory. We used a 0.820 micron laser source coupled with a 5 micronsingle-mode fiber to simulate an artificial star on the optical test bench ofUnISIS.

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10^-7 contrast ratio at 4.5 lambda/D: New results obtained in laboratory experiments using nano-fabricated coronagraph and multi-Gaussian shaped pupil masks