Airy disks of two point light-sources seen through a round aperture. The distance of the two sources matches the dawes-criterion (also called <a href="https://en.wikipedia.org/wiki/Dawes%27_limit" class="extiw" title="en:Dawes' limit">Dawes' limit</a>)
<dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle d={\frac {\lambda }{\sin \alpha }}}"><semantics><mrow class="MJX-TeXAtom-ORD"><mstyle displaystyle="true" scriptlevel="0"><mi>d</mi><mo>=</mo><mrow class="MJX-TeXAtom-ORD"><mfrac><mi>λ<!-- λ --></mi><mrow><mi>sin</mi><mo>⁡<!-- ⁡ --></mo><mi>α<!-- α --></mi></mrow></mfrac></mrow></mstyle></mrow><annotation encoding="application/x-tex">{\displaystyle d={\frac {\lambda }{\sin \alpha }}}</annotation></semantics></math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/db6e441c77cdd2bbf22e41584a34827d1ad5449f" class="mwe-math-fallback-image-inline" aria-hidden="true" style="vertical-align: -1.838ex; width:9.881ex; height:5.343ex;" alt="{\displaystyle d={\frac {\lambda }{\sin \alpha }}}"></span></dd></dl>
The brightness of the color shows the square-root of the intensity, since the patterns could hardly be seen at a linear scale.
<a href="//commons.wikimedia.org/wiki/User:Geek3" title="User:Geek3">Geek3</a>
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<span class="int-own-work" lang="en">Own work</span>