title: Isotropic image in structured illumination microscopy patterned with a spatial light modulator.
abstract: We developed a structured illumination microscopy (SIM) system that uses a spatial light modulator (SLM) to generate interference illumination patterns at four orientations - 0 degrees, 45 degrees, 90 degrees, and 135 degrees, to reconstruct a high-resolution image. The use of a SLM for pattern alterations is rapid and precise, without mechanical calibration; moreover, our design of SLM patterns allows generating the four illumination patterns of high contrast and nearly equivalent periods to achieve a near isotropic enhancement in lateral resolution. We compare the conventional image of 100-nm beads with those reconstructed from two (0 degrees +90 degrees or 45 degrees +135 degrees) and four (0 degrees +45 degrees +90 degrees +135 degrees) pattern orientations to show the differences in resolution and image, with the support of simulations. The reconstructed images of 200-nm beads at various depths and fine structures of actin filaments near the edge of a HeLa cell are presented to demonstrate the intensity distributions in the axial direction and the prospective application to biological systems.
authors.affiliation: National Synchrotron Radiation Research Center, 101 Hsin-Ann Road, Hsinchu Science Park, Hsinchu 30076, Taiwan, ROC. bjchang@nsrrc.org.tw
authors.forename: Bo-Jui
authors.initials: BJ
authors.lastname: Chang
authors.forename: Li-Jun
authors.initials: LJ
authors.lastname: Chou
authors.forename: Yun-Ching
authors.initials: YC
authors.lastname: Chang
authors.forename: Su-Yu
authors.initials: SY
authors.lastname: Chiang
mesh_terms: D000465:Algorithms; D002138:Calibration; D003198:Computer Simulation; D003599:Cytoskeleton / Q000378:metabolism; D004867:Equipment Design; D005583:Fourier Analysis; D006367:HeLa Cells; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007091:Image Processing, Computer-Assisted; D008027:Light; D008853:Microscopy / Q000379:methods; D018613:Microscopy, Confocal / Q000379:methods*; D008856:Microscopy, Fluorescence / Q000379:methods*; D016011:Normal Distribution