Tag Archives: Microscopy

Large field of view microscopes for mouse brain imaging

Posted on June 30, 2016 by P.T.R. Rupprecht

For typical confocal or two-photon microscopes that maintain (sub)cellular resolution, a high-magnification objective is needed (typically 16x, 20x or 25x). This in turn limits the field of view (FOV) to ⌀ 1.0-1.5 mm. For imaging in the mouse brain cortex, which is … Continue reading →

Posted in Calcium Imaging, Imaging, Microscopy | Tagged , , | 7 Comments

Fast z-scanning using a voice coil motor

Posted on April 6, 2016 by P.T.R. Rupprecht

We just published a paper on fast remote z-scanning using a voice coil motor. For 2P calcium imaging. It’s a nice paper with some interesting technical details. The starting point was the remote z-scanning scheme used by Botcherby et al. (2012) from … Continue reading →

Posted in Calcium Imaging, Imaging, Microscopy, Neuronal activity | Tagged , , , | 3 Comments

Modulating laser intensity on multiple timescales (x, y and z)

Posted on March 25, 2016 by P.T.R. Rupprecht

In point-scanning microscopy and especially when using resonant scanners, the intensity of the beam is typically modulated using a Pockels cell. For resonant scanning, the dwell time per micrometer is not constant along the scanned line, and one wants either to … Continue reading →

Posted in Calcium Imaging, Imaging, Microscopy | Tagged , , , | 1 Comment

Undistort/unwarp images for resonant scanning microscopy

Posted on February 16, 2016 by P.T.R. Rupprecht

For image acquisition using a resonant scanning microscope, one of the image axes is scanned non-linearly, following the natural sinusoidal movements of the resonant scanner. This leads to a distortion of the acquired images, unless a online correction algorithm or … Continue reading →

Posted in Calcium Imaging, Microscopy | Tagged , , , , | 1 Comment

Point spread functions

Posted on December 14, 2015 by P.T.R. Rupprecht

One way to characterize the quality of one’s microscope is to measure the point spread function (PSF), that is the image that is created by a point source  (which can be a fluorescent bead smaller than the expected size of the … Continue reading →

Posted in Microscopy | Tagged , , | 4 Comments

Gain and photons per pixel

Posted on March 2, 2015 by P.T.R. Rupprecht

In 2010, Labrigger wrote about how to measure the gain of a imaging system. As mentioned there in the comments, this was discussed in more detail by James Pawley in the confocal microscopy mailing list quite recently (following a question I asked to the list), and I was … Continue reading →

Posted in Uncategorized | Tagged , , | 1 Comment

Some interesting 2-photon microscopy papers

Posted on March 13, 2014 by P.T.R. Rupprecht

In the last few months, I built a special kind of 2P-microsope. In the meantime, I encountered some papers on microscope techniques which I found interesting and worth a side-note. Using AODs instead of galvoscanners for point-scanning: High-speed in vivo … Continue reading →

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