A flexible illumination system for Talbot lithography is presented, in which the Talbot mask is illuminated by discrete but variable incidence angles. Changing the illumination angle stepwise in combination with different exposure doses for different angles offers the possibility to generate periodic continuous surface relief structures. To demonstrate the capability of this approach, two exemplary micro-optical structures were manufactured. The first example is a blazed grating with a stepsize of 1.5 μm. The second element is a specific beam splitter with parabolic-shaped grating grooves. The quality of the manufacturing process is evaluated on the basis of the optical performance of the resulting micro-optical elements.

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The concept and the implementation of a compact and simplified echelle spectrometer are presented, and the working principle is demonstrated by first experimental measurements. The crucial element of the setup is a cross-grating, combining an echelle grating utilizing several higher diffraction orders (5th up to 11th) and a superposed perpendicular-oriented cross-dispersing grating. Two alternative manufacturing approaches for the cross-grating are presented and discussed. The first approach combines Talbot lithography for the deep echelle grating and interference lithography for the cross-dispersing structure. As a second approach, direct laser-beam writing was applied. The compact echelle spectrometer covers a spectral range from 380 to 700 nm and offers a spectral resolution of ∼2 .

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We present an effective modeling approach for a fast calculation of the Talbot carpet from an initially 2-dimensional mask pattern. The introduced numerical algorithm is based on a modified angular-spectrum method, in which it is possible to consider the border effects of the Talbot region from a mask with a finite aperture. The Bluestein's fast Fourier transform (FFT) algorithm is applied to speed up the calculation. This approach allows as well to decouple the sampling points in the real space and the spatial frequency domain so that both parameters can be chosen independently. As a result an extended three-dimensional Talbot-carpet can be calculated with a minimized number of numerical steps and computation time, but still with high accuracy. The algorithm was applied to various 2-dimensional mask patterns and illumination setups. The influence of specific mask patterns to the resulting field intensity distribution is discussed.