moire - Does the human eye see moiré? - Photography Stack Exchange
What caused this pattern of lines (moire?) in this picture I scanned from a book? Ask Question Asked 10 years, 5 months ago Modified 10 years, 5 months ago
artifacts - What caused this pattern of lines (moire?) in this picture ...
As prevoiusly stated Moire happens when two patterns interact, specially if the two patterns have a "frequency" (read size of the repeating characteristic) close enough to each other.
The moire like pattern only becomes apparent on flattening the image. I tried another series of images that were taken facing south and didn't get the strange effect.
The effect is called Moire. It is caused by the grid pattern of the photosites in your sensor and the grid of pixels in the screen interacting. It happens when the grids do not exactly line up. It can occur with any gird or parallel lines. It is explanined in more depth here. To reduce this effect try to reduce how much of line the screen is to the sensor.
moire - Is there a name for artifacts for taking a photo of LCD / LED ...
As to your question about producing moire patterns when the sensor has higher resolution (resolvable line pairs) than the lens: I'm skeptical that that's possible, since an optically blurred image can't be sharpened by using more pixels. You'll just get a better final image/print of the blur itself.
Moire patterns caused by sampling a continuous image are aliases. The same math applies to them just as it applies to high frequencies aliasing into a audio stream and sounding like background whistles.