| Binary optics is a new and developing branch of optics based onoptical wave diffraction theory, computed generate holography and aleading science formed by coupling and microelectronics. Binary optics,also called diffractive optical elements, have many advantages, such assmall size, light weight, replication easily, low cost, high diffractionefficiency, many design variables, wide range of optional materials,peculiar chromatic dispersion performances, and so on. Therefore theycan implement some new functions, for example micro-miniature, array,integration and arbitrary wave transformation, which are difficult fortraditional optical elements to realize. This all made Binary optics have arapidly developing.Talbot effect and the fractional Talbot effect based on Fresneldiffraction is an important method of the fabrication of optical arrayilluminator (AIL). The basic theory of Talbot array illuminator is todesign a phase grating with special phase distribution. Under theillumination of the plane wave, the Fresnel image on special position turnto be an amplitude grating, that is spot array.In this paper, we propose a new method for fabrication ofbacklighting Flat Panel Display (FPD) by binary optics thus Talbotgratings can generate array uniform light spots with high-efficiency.Comparisons are made for the typical array illuminators such asDammann grating, Fresnel lens array, Talbot gratings array. Taking thelateral-guided cold-cathode fluorescent lamp backlighting system forexample, the configuration and performance of the conventionalbacklighting system are introduced. Then we seeked the solutions of theone-dimensional to two-dimensional Talbot effect optical arrayilluminator(AIL). From the analysis of the image at the Talbot distanceand the fractional Talbot distance we come to a conclusion that phasegratings can generate uniform spots array at a particular Talbot distance.At the end of the paper a number of other effective methods to make the spots more Uniform are proposed.
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