Why do “light beams” appear from light sources when you squint, especially in a dark environment?

Question

Why do “light beams” appear from light sources when you squint, especially in a dark environment?

In: Biology

Answer 1

It is actually your eyelashes creating diffraction spikes. If you nudge your eyelashes while looking at a phone torch you can test it out (not too close or bright though. Also, I used to think it was astigmatism but that more causes angular slanted lines in one direction whereas diffraction spikes are from a range.