Why Didn't Lex Luthor Ever Think Of This?

So how does Batman, even a Batman-turned-evil-by-super-hypnosis, trap Superman in his space prison?

First step: transmit a really stupid code to Earth:

Now, this is on all the wire services. Is this really a wise code? How long until someone dopes it out? Why not just use pig latin, if you're going to be that obvious?

Anyway...

See, yellow sun! Perfectly safe!!

Damn, that sun is yellow! No danger for Superman here!

Yeah, how?

Really?

Let's set aside the obvious difficulties of keeping that "huge filter" perfectly synched with the sun's movements. Such a thing still couldn't actually work, could it? You can't defeat Superman with what is essential just a huge lens gel, right?

OK, I stand corrected: it works. Still, only 99%, eh? I smell a solution to our problems...Stay tuned...

As for this post's title, sure, Luthor could do something like that...but Earth has enough other heroes that could put the kibosh on such a device...

From World's Finest #145 (1964), as reprinted in World's Finest #197 (1970)