Beam shaping in the nonparaxial domain of diffractive optics.

We address the problem of shaping the radiant intensity distribution of a highly nonparaxial coherent field by means of a diffractive element located in the plane of the beam waist. To be capable of wide-angle energy redistribution the element must necessarily contain wavelength-scale transverse features, and consequently it must be designed on the basis of rigorous diffraction theory. We consider, in particular, wide-angle Gaussian to flat-top beam shaping in one dimension. Scalar designs are provided and their validity is evaluated by rigorous diffraction theory, which is also used for optimization deep inside the nonparaxial domain, where the scalar designs fail. Experimental verification is provided by means of electron-beam lithography.

[1]  C. J. Kastner,et al.  Beam profile shaping for laser radars that use detector arrays. , 1982, Applied optics.

[2]  Mohammad R. Taghizadeh,et al.  Rigorous diffraction analysis of Dammann gratings , 1991 .

[3]  Filippus S. Roux,et al.  Intensity distribution transformation for rotationally symmetric beam shaping , 1991 .

[4]  Karl Knop,et al.  Rigorous diffraction theory for transmission phase gratings with deep rectangular grooves , 1978 .

[5]  Jari Turunen,et al.  Eigenmode method for electromagnetic synthesis of diffractive elements with three-dimensional profiles , 1994 .

[6]  M. Nevière,et al.  The Homogeneous Problem , 1980 .

[7]  D. Shafer,et al.  Gaussian to flat-top intensity distributing lens (A) , 1982 .

[8]  A. Friberg,et al.  Acousto-optic conversion of laser beams into flat-top beams , 1993 .

[9]  K Murata,et al.  Reshaping collimated laser beams with Gaussian profile to uniform profiles. , 1983, Applied optics.

[10]  Carl C. Aleksoff,et al.  Holographic conversion of a Gaussian beam to a near-field uniform beam , 1991 .

[11]  M. Kuittinen,et al.  Exact-eigenmode model for index-modulated apertures , 1996 .

[12]  N C Roberts Beam shaping by holographic filters. , 1989, Applied optics.

[13]  D L Shealy,et al.  Refractive optical systems for irradiance redistribution of collimated radiation: their design and analysis. , 1980, Applied optics.

[14]  Olof Bryngdahl,et al.  Electromagnetic diffraction analysis of two-dimensional gratings , 1993 .

[15]  Jan Westerholm,et al.  Storage of multiple images in a thin synthetic Fourier hologram , 1991 .

[16]  Frank Wyrowski,et al.  Consequence of illumination wave on optical function of non-periodic diffractive elements , 1994 .

[17]  Huttunen,et al.  Scattering of partially coherent electromagnetic fields by microstructured media. , 1995, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics.

[18]  Mohammad R. Taghizadeh,et al.  Synthetic diffractive optics in the resonance domain , 1992 .

[19]  M T Eismann,et al.  Iterative design of a holographic beamformer. , 1989, Applied optics.

[20]  Ross C. McPhedran,et al.  Theory of Crossed Gratings , 1980 .

[21]  Olof Bryngdahl,et al.  Design strategy of diffractive elements with prescribed diffraction angles in non-paraxial region , 1995 .

[22]  Wai-Hon Lee Method for converting a Gaussian laser beam into a uniform beam , 1981 .

[23]  M. Taghizadeh,et al.  Kinoform array illuminators in fused silica , 1993 .