Re: Piezo scanning stage induced image distortion

Posted by Lu Yan on
URL: http://confocal-microscopy-list.275.s1.nabble.com/Piezo-scanning-stage-induced-image-distortion-tp7584896p7584905.html

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Hi Mark,

My detector sampling rate and the pixel clock are sync'ed via the an AO
task and a Counter task in the labview program. So would you separately
control the sampling rates for the ramp and the sensor?

Thanks,
Lu
On 2016年3月17日 周四 at 下午3:37 Yan, Lu <[hidden email]> wrote:

> Hi Eric,
>
> The ramp voltage looked fine on oscilloscope. I was using a photon
> counting module for the detection.
>
> Lu
>
> On 2016年3月17日 周四 at 下午1:18 Eric Marino <[hidden email]> wrote:
>
>> *****
>> To join, leave or search the confocal microscopy listserv, go to:
>> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
>> Post images on http://www.imgur.com and include the link in your posting.
>> *****
>>
>> Have you looked at the ramp voltage on an oscilloscope to check for
>> noise? What camera are you using (sCMOS, CCD)? are you decreasing the
>> exposure when you increase the scanning frequency?
>>
>>
>> Eric Marino
>> [hidden email]
>>
>>
>>
>> > On Mar 17, 2016, at 10:59 AM, Yan, Lu <[hidden email]> wrote:
>> >
>> > *****
>> > To join, leave or search the confocal microscopy listserv, go to:
>> > http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
>> > Post images on http://www.imgur.com and include the link in your
>> posting.
>> > *****
>> >
>> > Hi Eric,
>> >
>> > The images are all taken at the fixed sample plane. The sample is a
>> simple
>> > grating pattern. I took these images at different scanning speed.
>> >
>> > Lu
>> >
>> > ------------------------------------------------------------------
>> > -------------
>> > Lu Yan
>> > Nanostructured Fibers and Nonlinear Optics Laboratory
>> > Electrical and Computer Engineering
>> > Boston University
>> > Rm. 505, 8 Saint Mary's St., Boston, MA 02215
>> > +1.617.353.0286 (office) | 617.358.5917 (lab)
>> > [hidden email]
>> > ------------------------------------------------------------------
>> > -------------
>> >
>> > On Thu, Mar 17, 2016 at 10:37 AM, Eric Marino <[hidden email]>
>> wrote:
>> >
>> >> *****
>> >> To join, leave or search the confocal microscopy listserv, go to:
>> >> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
>> >> Post images on http://www.imgur.com and include the link in your
>> posting.
>> >> *****
>> >>
>> >> Hi Lu,
>> >>
>> >> Are the images a single plane or projected images?
>> >>
>> >> Eric Marino
>> >> [hidden email]
>> >>
>> >>
>> >>
>> >>> On Mar 17, 2016, at 10:08 AM, Yan, Lu <[hidden email]> wrote:
>> >>>
>> >>> *****
>> >>> To join, leave or search the confocal microscopy listserv, go to:
>> >>> http://lists.umn.edu/cgi-bin/wa?A0=confocalmicroscopy
>> >>> Post images on http://www.imgur.com and include the link in your
>> >> posting.
>> >>> *****
>> >>>
>> >>> Dear listers,
>> >>>
>> >>> I am encountering a problem with my piezo scanning stage (sample
>> >> scanning)
>> >>> in the microscopy setup. I found that at some discrete line scanning
>> >>> frequencies (lines/s), the grating sample I imaged got some
>> distortions
>> >>> along the fast axis (the horizontal axis in following images). See
>> this
>> >>> link for some images:
>> >>>
>> >>
>> https://www.dropbox.com/s/9r0e2rea8oaepgi/Screenshot%20-%203_17_2016%20%2C%209_49_00%20AM.png?dl=0
>> >>>
>> >>> As you can see, for example, at 30 Hz, it seemed that the grating was
>> >>> splitting into multiple lines; and at 40Hz, they are also pretty bad.
>> I
>> >> am
>> >>> using a bidirectional sawtooth voltage pattern to feed the piezo. So I
>> >> was
>> >>> wondering if anyone has similar experience on this? I switched to a
>> new
>> >>> scanning stage, but the distortion still existed, and it did not
>> change
>> >> as
>> >>> field of view and pixel size. Does anyone have an ideal what might be
>> >> wrong?
>> >>>
>> >>> Thanks a lot,
>> >>> Lu
>> >>
>>
>