Flat‐top illumination profile in an epifluorescence microscope by dual microlens arrays

  title={Flat‐top illumination profile in an epifluorescence microscope by dual microlens arrays},
  author={Frank A. W. Coumans and Edwin van der Pol and Leon W.M.M. Terstappen},
  journal={Cytometry Part A},
Low uniformity in illumination across the image plane impairs the ability of a traditional epifluorescence microscope to quantify fluorescence intensities. Two microlens arrays (MLAs) were introduced into the illumination path of two different epifluorescence microscope systems to improve the uniformity of the illumination. Measurements of the uniformity of illumination were performed with a CCD camera in the focal plane and with fluorescent beads in the image plane. In semi critical alignment… 
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  • T. Sales
  • Physics
    SPIE Optics + Photonics
  • 2003
Practical results are presented that elucidate the capabilities of structured microlens arrays to perform complex beam shaping tasks, both intensity control and spatial energy distribution, with high efficiency (mostly limited by surface losses) and without the presence of image artifacts.