According to court records ... Lorraine filed her divorce petition Thursday in Los Angeles to make the split from her husband, Robert Michael Tomlinson, official, legally.

According to the docs they have no minor children together ... although there have been reports they have a teenage daughter. They were married on June 25, 2017.

Lorraine is asking the court to award her spousal support, and to block the court's ability to award support the other way around.

Lorraine played inmate Yvonne "Vee" Parker on season 2 on the hit Netflix show, 'OITNB.' She's also appeared on many other TV shows ... including "Where I Live," "Amazing Grace," "Law & Order," "Judging Amy," "Ugly Betty" and "Friday Night Lights."

But, Vee was definitely her breakout role -- she even won a 2015 SAG Award for it, along with her co-stars. Lorraine also garnered rave reviews from TV Guide and Vanity Fair.

She's also done several films, and got praise for her role in "Selma."