Looks like Dr Light, the Dr. Kimiyo Hoshi version, will be appearing in season two of The Flash. According to TVLine, both Cisco and Caitlin mention the character in passing in season two of Arrow, but the plan is to bring in the character for this upcoming season of The Flash, setting up Light way far in advanced.
This will not be the Arthur Light version of the character though. According to the report, it's going to be the "female version" of the character. We're assuming that means Kimiyo Hoshi, who first appeared in CRISIS ON INFINITE EARTHS #4 back in 1985. Hoshi can control and manipulate light and is the next metahuman to make their way to Central City.
The Flash returns to CW on October 6.