http://confocal-microscopy-list.275.s1.nabble.com/Numerical-aperture-and-spatial-resolution-tp7591293p7591296.html
> *****
> 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.
> *****
>
> The best demo I have found is to make it physically tangible - a demo using
> your own hands. Imagine that the wavelength of your light is the length of
> your hand (fingertip to wrist). That would mean that the base of your
> fingers would be a 180° phase shift from your finger tip. Now rest your
> elbows on a table and point your hands in line with your forearms with the
> finger tips touching one another. This is the center of the Airy disk as
> the waves are perfectly in phase. Now, while keeping your elbows in place,
> rotate your forearms until your fingertips on one hand reach the base of
> the fingers on the other. The light is now 180° out of phase - this is the
> first dark ring (node) of the Airy disk. Try this with your elbows close
> together (small angle = low NA), and elbows wide apart (large angle = high
> NA). You will find you have to move a lot farther to the side to get the
> first node with the small angle than the large angle.
>
> Now, technically this demo traces a petzval surface, but the analogy works
> well enough to get the point across. I've even had students do this demo
> during tests.
>
> For more visual learners, Paul Falstad's wave applet:
>
http://falstad.com/ripple/ has a diffraction demo built in. It also has a
> lot of other great demos, including Rayleigh scattering, Mie
> scattering/lensing, single vs multimode fiber, holographic gratings,
> refraction, etc. This other wave applet of his is also great:
>
http://falstad.com/wave2d/ As an added bonus, the site also has a circuit
> simulator for when you want to cover CMOS cameras, an animation showing
> orbital transitions which is perfect for fluorescence, second harmonic
> excitation, and stimulated emission, and a Fourier Transform visualizer
> which is perfect for explaining image processing and mode locking in
> lasers.
>
> Hope this helps,
> Ben Smith
>
> On Sat, Sep 19, 2020 at 2:40 AM F Javier Diez Guerra <
[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.
> > *****
> >
> > Hello,
> >
> > I wonder if anybody in the list could help.
> >
> > I want to convey to biology undergraduate students (very allergic to
> > physics and mathematics) the understanding of the relationship between
> > numerical aperture and spatial resolution.
> >
> > I have already given them links to the different microscopy primer
> > sites. They find difficult to understand why the airy disk is generated
> > in the image plane, how the diffraction orders affect resolution and why
> > increasing NA reduces the image spot.
> >
> > Could anybody share a basic and intuitive infographic slide, animation
> > or any other resource that could help to ease comprehension in this
> > context?
> >
> > Thanks
> >
> > Javier
> >
> >
> > --
> > Fco. Javier Diez-Guerra, PhD
> >
> > Servicio de Microscopía Confocal
> > Centro de Biologia Molecular Severo Ochoa
> > C/ Nicolás Cabrera, 1
> > Campus de Cantoblanco
> > 28049 Madrid
> > SPAIN
> >
> > Tel +34 91 196 4612
> > e-mail:
[hidden email]
> >
>
>
> --
> Benjamin E. Smith, Ph. D.
> Imaging Specialist, Vision Science
> University of California, Berkeley
> 195 Life Sciences Addition
> Berkeley, CA 94720-3200
> Tel (510) 642-9712
> Fax (510) 643-6791
> e-mail:
[hidden email]
>
>
https://vision.berkeley.edu/faculty/core-grants-nei/core-grant-microscopic-imaging/>