It means the cinema, or "the movies" as we say in the U.S. I'm pretty sure it dates to the 1950s. Before that, the movies were called "the SILVER screen." During the 1950s, the movie industry was terrified by television. Why would anyone go to the movies when they could watch TV at home? They fought by refusing to license movies to be shown on television AT ALL. It seems hard to believe but MGM did not allow the 1939 hit "Gone With The Wind" to be shown on TV until 1956! During the 1950s the movie industry constantly emphasized the differences between their "big screen" and the small TV screen (21" would have been the standard size for a big living-room TV, and it would usually have been black-and-white--only rich people had color TVs in the 1950s). They also introduced wide-screen processes like Cinerama, Cinemascope to make the picture bigger, and made a big deal about Technicolor and sterephonic sound.

The big screen is more of a colloquial way in which one can refer to the cinema- the idea is that the cinema is the 'big screen. With the sentence you put you could say 'the evolution of Batman on the big screens a whole', although I would need some more context to give you an alternate sentence. So just to reiterate, 'big screen' is just a more informal way of implying the platform in which you would watch a movie: for example, 'batman is coming to the big screen near you this autumn'. hope I could help :)

Hi, we say 'big screen' to imply the cinema usually, although you can now buy 'big screen TVs'.