don't know if it's the same type of tech as my old Sony SXRD, but, it looks like a failing Optical Block rearing it's ugly head. or whatever the DLP term is. had that tv for 10 + years before going 4K to replace it.
i'm sure someone with a Mitsi DLP that has experienced that will be along shortly. best of luck
TCL-65R615, 55P605 DV/HDR10 & 49S405 HDR10, Philips BDP7501, BPD7502 UHD Players
Oppo BDP-105D, 105, 93, Marantz AV7702MKII, NR1607. Xbox One S
Emotiva XPA5,UPA2, UPA200 & Mini X Amps
Speakers, Polk SDA-2, Monitor 10A & 5A, Axiom M80,
VP180, QS8, M2, QS4, ATMOS 7.1.4 & 5.1.2 NYGiants!