title: Active Microscope Stabilization in Three Dimensions Using Image Correlation.
abstract: BACKGROUND
  Super-resolution microscopy techniques are often extremely susceptible to sample drift due to their high spatial resolution and the long time needed for data acquisition. While several techniques for stabilizing against drift exist, many require complicated additional hardware or intrusive sample preparations. We introduce a method that requires no additional sample preparation, is simple to implement and simultaneously corrects forx,yandzdrift.
  
  
  RESULTS
  We use bright-field images of the specimen itself to calculate drift in all three dimensions:x,yandz. Bright-field images are acquired on an inexpensive CCD. By correlating each acquired bright-field image with an in-focus and two out-of-focus reference images we determine and actively correct for drift at rates of a few Hertz. This method can maintain stability to within 10 nm forxandyand 20 nm forzover several minutes.
  
  
  CONCLUSIONS
  Our active drift stabilization system is capable of simultaneously compensatingx,yandzdrift through an image-based correlation method that requires no special sample treatment or extensive microscope modifications. While other techniques may provide better stability, especially for higher frequency drift, our method is easy to implement and widely applicable in terms of both sample type and microscopy technique.
authors.affiliation: Department of Pharmaceutical Chemistry, University of California, San Francisco, ryan.mcgorty@ucsf.edu , daichi.kamiyama@ucsf.edu , bo.huang@ucsf.edu.
authors.forename: Ryan
authors.initials: R
authors.lastname: McGorty
authors.affiliation: Department of Pharmaceutical Chemistry, University of California, San Francisco, ryan.mcgorty@ucsf.edu , daichi.kamiyama@ucsf.edu , bo.huang@ucsf.edu.
authors.forename: Daichi
authors.initials: D
authors.lastname: Kamiyama
authors.affiliation: Department of Pharmaceutical Chemistry, University of California, San Francisco, ryan.mcgorty@ucsf.edu , daichi.kamiyama@ucsf.edu , bo.huang@ucsf.edu.
authors.forename: Bo
authors.initials: B
authors.lastname: Huang
keywords: image correlation; stage stabilization; super-resolution microscopy