Do you ever heard of “Rainbow Effect”? Probably, you have read it or heard from salesperson while shop for projector.
As the name implied, the rainbow effect which comprise of colorful layers, which is a visual phenomenon that possible on many single-chip DLP projectors. Following are the side-to-side illustration on the Rainbow Effect (Circle in White).
The visual artifact have no immediate impact on your viewing, however it may cause discomfort on your eye balls over long period watching. Some may encounter migraine, but with very rare occasion.
Refer video link on how it appear: