Abstract: Optical wave data for a semiconductor device design is divided into regions. First wavefront engineering is performed on the wave data of each region, accounting for just the wave data of each region and not accounting for the wave data of neighboring regions of each region. The optical wave data of each region is normalized based on results of the first wavefront engineering. Second wavefront engineering is performed on the wave data of each region, based at least on the wave data of each region as has been normalized. The second wavefront engineering takes into account the wave data of each region and a guard band around each region that includes the wave data of the neighboring regions of each region. The second wavefront engineering can be sequentially performed by organizing the regions into groups, and sequentially performing the second wavefront engineering on the regions of each group in parallel.

Abstract: A structure and a method for an equi-brightness optimization. The method may include projecting a plurality of bright patterns having a plurality of bright points and a plurality of dark patterns having a plurality of dark points on a substrate, generating a plurality of joint eigenvectors of the plurality of bright points and a plurality of dark points, selecting a predetermined number of joint eigenvectors to project the plurality of bright patterns, generating a plurality of natural sampling points from the plurality of bright points, wherein the plurality of natural sampling points has a substantially equal intensity, and obtaining a representation of an aperture from the plurality of natural sampling points, wherein an image of the representation of the aperture has a substantially uniform intensity.

Abstract: A method for illuminating a mask to project a desired image pattern into a photoactive material is described. The method includes receiving an image pattern. Determining a relationship between source pixels in a set of source pixels to desired intensities at one or more points in the image pattern is performed. Linear constraints are imposed on a set of intensity values based on one or more contingent intensity condition. The contingent intensity conditions include integer variables specifying contingent constraints. The method includes determining values of the set of intensity values in accordance with the linear constraints, using a constrained optimization algorithm. The set of intensity values represents intensities of a set of source pixels. The set of intensity values are output. Apparatus and computer readable storage media are also described.

Abstract: A mode-selective add/drop unit for a mode division de/multiplexing device includes an optical ADU waveguide adapted for coupling to an input optical waveguide. The optical ADU waveguide includes at least one region providing optical signal coupling between the ADU waveguide and a multi-mode waveguide; and, one or more phase matching regions for controlling a relative or absolute phase difference between an electromagnetic wave (EMW) carried in the ADU waveguide and the multi-mode waveguide. The mode-selective add/drop unit may further include a transition region connecting the coupling region and a phase matching region, wherein a shape of a transition region is governed by a polynomial function, exponential function, logarithmic function, trigonometric function or, any combination of these functions.

Abstract: A structure and a method for an equi-brightness optimization. The method may include projecting a plurality of bright patterns having a plurality of bright points and a plurality of dark patterns having a plurality of dark points on a substrate, generating a plurality of joint eigenvectors of the plurality of bright points and a plurality of dark points, selecting a predetermined number of joint eigenvectors to project the plurality of bright patterns, generating a plurality of natural sampling points from the plurality of bright points, wherein the plurality of natural sampling points has a substantially equal intensity, and obtaining a representation of an aperture from the plurality of natural sampling points, wherein an image of the representation of the aperture has a substantially uniform intensity.