The Charlie's Angels star launched the company with a make-up range in 2013, and it has since grown to include perfume and other beauty products.

Now Barrymore has unveiled a collection of sunglasses and regular optical frames, which will be sold exclusively at U.S. retailer Wal-Mart.

Explaining her design process for the accessories, Barrymore tells Eonline.com, "The best place for eyewear inspiration is flea markets and then also department stores and then hybriding (sic) the two, seeing what's current and important to people right now and cutting edge and then bringing that vintage feel to it because everything is always repeating itself. Everybody is always pulling from yesteryear."

Praising the star for her hands-on approach, Wal-Mart representative Carmen Bauza says, "Drew is involved... in every detail. It's not like she's managing from somewhere out there and has someone else is doing it. I know when it hits the shelves, it's got her seal of approval and that gives me peace of mind."

Barrymore isn't the only celebrity to branch out into the eyewear industry - Gwen Stefani is working with Tura Inc. bosses to create a line of glasses for her existing clothing and accessories brands L.A.M.B. and GX by Gwen Stefani, which is expected to launch next year (16).