Firstly, I looked at 1950/60s movies to understand invisibility.
In this film, invisibility is depicted by the movement of objects, seeming that someone invisible is actually move them or by using a white silhouette highlight where the character is.
In this film, the invisible man is often wearing clothes which will define his shape, when these are off, he becomes transparent.
Once again, the clothes are the accessory that defines the human shape,This technique is often used to scare people, the idea of having clothes,but no definite visible human character is using them.
While in old movies, producers use different techniques to demonstrate invisibility, nowadays, such things are depicted completely different, instead of having objects flying around the room in a silly way or cheap special effects of white faded sillhouettes of the characters, theses effects are depicted in a cooler way, only for the purpose of enternaing and create more action.
In today's cinema, invisibility is associated to invisible forces such gravitation and magnetic force explosions, or an almost invisible layer of the character, just showing the outline of the character, this is possible by the use of powerful CGI effects. I do think this advance in cinema is mainly related to the advance of technlogy and also to the urge to satisfy the younger public, who would think that the primitive techniques used in the 50's cinema were old-fashioned and funny.
This techniques can be see in the Invisible Woman from the film Fantastic 4 or the Jedi gravitional force in the new Star Wars Films and Video Games.
Star Wars: The Force Unleashed