No one knows.
Laptops may have been invented by any would-be laptop inventor, and there is no originator that claims to be the original creator. It's truly an open-source design. At best we can track its origins back to World War II as a name acronym (portable logical automaton or personal labor assistant).
Laptops may also have been directly inspired at the MIT Man-Machine Laboratory in 1957, by mathematician Alan JF Thanks for asking!...