This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Circular aperture withlens. Circularaperturewith lens svg ja Transferred from org en Original uploader was Mmm at org en Released into the public domain by the author en Mmm original upload log page en Circularaperturewithlens Mmm bytes no Diffraction
Page 2023 Free-images.com. All images are Public Domain