A SF novel about the invisible globes that try to take over the world

Question

It's a 60s or 70s SF novel. Maybe by a French or Japanese author.

The plot is that some prominent scientists suddenly dies in strange occasions. It turns out they finds a kind of eye drops enabling them to see previously invisible light globes floating in the sky. These light globes suck on human's emotions and thoughts for food. The light globes would kill anyone who detects their existence. The victims can only escape the fate if they can keep their minds occupied by other things when they see the globes around. At the end, some scientists develop a sort of reflective antenna that can burn the light globes and won the war with them.

Answer 1

This is Eric Frank Russell's Sinister Barrier which first appeared in Unknown in 1939. See Wikipedia.

Your description is spot-on: Scientists dying apparently randomly, eye treatments, which allow one to see the Vitons (so named) as floating globes of light, and final human victory with antennas sending a beam of radio energy which disrupts them. (Russell is English, though.)