The company claims that photos will display as much as four times bigger on a large desktop monitor.
The changes to Facebook's photo-sharing interface suggest that the company is responding to growing competition from sites like Pinterest and Instagram and from Google+, which includes a full-screen photo viewer, according to Patrick Moorhead, the principal analyst at Moor Insights & Strategy.
"This is absolutely a defensive move to thwart off any advances that either Instagram or Pinterest will make," Moorhead said. User appreciate how Google+ handles photographs, he said.
Some social media enthusiasts are spending less time on Facebook and more on Instagram and Pinterest, he said.
Facebook did not immediately respond to a request for comment.
Brian Blau, an analyst at Gartner, said the move would bring Facebook "up to speed" with other photo-sharing services. Its previous photo viewer "seemed to be kind of a tacky addition to what is otherwise a nicely laid out service," he said.
He sees the changes as part of Facebook's ongoing efforts to keep users on its platform for longer.
"Google, Facebook and Apple are all trying to expand their own feature sets so they can keep users on their sites," he said. "It is competition, but not over photo sharing per se."
Facebook's newly launched photo-viewing features currently work in up-to-date Chrome and Firefox Web browsers only. Users can upload photographs with a maximum resolution of 2048-by-2048 pixels.
The IDG News Service