4Pi spectral self-interference microscopy.
Spectral self-interference microscopy (SSM) relies on the balanced collection of light traveling two different paths from the sample to the detector, one direct and the other indirect from a reflecting substrate. The resulting spectral interference effects allow nanometer-scale axial localization of isolated emitters. To produce spectral fringes the difference between the two optical paths must be significant. Consequently, to ensure that both contributions are in focus, a low-numerical-aperture objective lens must be used, giving poor lateral resolution. Here this limitation is overcome using a 4Pi apparatus to produce the requisite two paths to the detector. The resulting instrument generalizes both SSM and 4Pi microscopy and allows a quantification of SSM resolution (rather than localization precision). Specifically, SSM is shown to be subject to the same resolution constraints as 4Pi microscopy.
Davis
Brynmor J
BJ
Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA. bryn@uiuc.edu
Dogan
Mehmet
M
Goldberg
Bennett B
BB
Karl
William C
WC
Unlü
M Selim
MS
Swan
Anna K
AK
D004867:Equipment Design; D019544:Equipment Failure Analysis; D007089:Image Enhancement / Q000295:instrumentation*; D021621:Imaging, Three-Dimensional / Q000295:instrumentation; D054023:Lasers, Semiconductor; D007909:Lenses; D008857:Microscopy, Interference / Q000295:instrumentation*; D012016:Reference Values; D012031:Refractometry / Q000295:instrumentation / Q000379:methods; D012680:Sensitivity and Specificity