Hi everyone,
I am currently working on microfluidic droplet generation experiments. When I capture images of the droplets under the microscope, I notice that the images appear distorted (for example: the droplets look stretched, compressed, or irregularly shaped).
My questions:
- What could be the possible causes of image distortion in microfluidic droplet imaging?
- How can I troubleshoot or correct this distortion?
- Are there any recommended settings or calibration steps for imaging microfluidic droplets accurately?
I have attached an example image showing the distortion. The image was taken using a 10x objective lens.
Thank you very much for your help!
Any chance you sheered your droplets? Like by placing a cover slid on them that moved a bit?
But to actually answer your question: Put something with right angles under the microscope. There are reference targets. The good ones are pretty expensive, but as you are using a pretty low magnification you can get away with a cheap one. May be even a cross of graph paper or Millimeter paper might do. If that won’t work due to lighting you can probably just scratch a cross into a acetate sheet with a protractor triangle and a sharp blade.
Edit: May be a corner of a cover slid would also do and may be even more readily available.
My feeling is that this is most likely to be the droplet shape itself.
That is easy to test: take an image containg a distorted droplet, then move the stage and take another image. If the droplet is the same shape in both images it is very unlikely to be dostortion in the imaging system.
There is usually more distortion at the edges and less in the centre, so comparing the droplet in those locations will show it. The distortion is usually ‘radial’, so a stretch seen when at one corner would go in a different direction in the next corner.
