Uniform illumination, including uniform irradiance and color uniformity, is of indispensable importance for numerous imaging and sensing applications. These illumination designs typically comprise one or multiple light-emitting diodes (LEDs), or feature halogen sources, which are preferred for spectroscopy applications. We present an overview of different design strategies enabling a uniform illumination, taking the extended source characteristics into account, while aiming to compare different optical design approaches with respect to cost, efficiency, complexity, scalability and robustness. Four case-studies will be compared: (1) considering geometrical optimization of the source positions, (2) combination of a halogen source array with a biconic aspheric lens array, (3) combination of a multi-chip LED with a biconic lens array and Fresnel lens, and (4) the combination of a multi-chip LED with a Shell-Mixer. A design-for-manufacturing approach is applied for all designs, considering integration and robustness, paving the way towards industrial uniform illumination optics.
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