christmas light illusion

[bearfinch]

Tonight when i was outside I noticed that strands of all-indigo blue halogen Christmas lights kind of looked blurry and out of focus. At first I thought it was my eyes, but after seeing starnds of them in a few different places, especially where they were beside other colours that were crystal clear, I noticed it again. It actually botheed my eyes a bit and I squinted involuntarily looking at them.

I'm taking a guess that the eyes perecieve deep blue light against a dark background differently somehow. Or else my ocular nerves are messed up.