Hi, I'm searching for this font from the 80's. It's from the credits of "Luxo Jr." from 1986, and it's also used in "The Adventures of André & Wally B.".
Likely a simple standart font back than.

It's -NOT- FF DIN Round. The lowercase "g" is different.

CMU Sans Serif  Suggested by cvni81 

This is very probably a version of Computer Modern Sans made to have round strokes. Since Computer Modern was made with METAFONT, it has a Lot of customizable variable parameters, probably one of them being the edge roundness. There is a kinda rounded version available but not this rounded. I think if one wanted to make Exactly the font shown here, they'd have to modify the parameters used using METAFONT (which is probably what the people at Pixar did in 1986!)
The closest (though unrounded) i have that doesn't involve that is CMU Sans Serif.