Publications by authors named "Mahesh Pitchumani"

A novel on-axis one-element polarization-independent light in- and out-coupling mechanism for surface plasmon resonance (SPR) is proposed. The system utilizes an integrated high-NA concentric chirped grating to both focus the incident light on the metallic film and collimate the reflected beam onto a CCD array to extract the SPR signal. With NA up to 1.

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An innovative fabrication technique is introduced that is based on multiple-exposure techniques for micro-optics fabrication. This approach is compatible with conventional lithography systems used in integrated circuit manufacturing and can be applied to thick and thin photoresists and is based on additive lithographic techniques introduced elsewhere [Appl. Opt.

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In optical lithography the degradation of image quality due to aberrations present in the exposure tool is a serious problem. Therefore it is desirable to establish a reliable aberration measurement procedure based on the analysis of printed images in the photoresist. We present what is to our knowledge a new method for characterizing the aberrations of an exposure tool using a hybrid diffractive photomask.

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An innovative fabrication technique is introduced that is based on multiple-exposure techniques for micro-optics fabrication. This method utilizes various exposure times and combinations of binary and analog photo masks to sculpture complex photoresist profiles. It also demonstrates the fabrication of analog structures from the multilevel structures thus formed by using resist reflow.

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