I'm quite excited to show you the focal properties of my microscopically small lenses that I made using photolithography. These lenses are actually Fresnel zone plates which use diffraction as the method for focussing the light. They were made using the DIY maskless wafer stepper.

The lenses have more than one focal plane, and you can easily observe the 1st, 2nd and 3rd order focal planes when they are used in combination with monochromatic light sources.

I used a static image from a video on meta surfaces. Please check out this video if you want to know more about this subject:    • Shrinking microscope lenses  

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