Thanks for the fast reply.
Yeah, I have already considered Vermilo but, as you said, it has some things that don't suit my needs.
I have one Adesso Bluetooth keyboard and it is horrible, disconnecting every now and then without any recognizable reason. I tried several Bluetooth adapters, some of them are embedded on different motherboards, and I had always the same problems. Maybe it is such thing only with this keyboard, but I am not sure if I want to experiment with another Bluetooth keyboard again.
I don't enter to BIOS very often, but from time to time I am getting some problems during boot-up when I need to use a keyboard, e.g. just to press F2 or something like that. I could use Bluetooth keyboard in such case, but only if it has a dual mode, i.e. if it could be used with a wire.
Besides, I want a dual mode keyboard if the new one has the same problems with the wireless as the current one, so I could use it in the wired mode at least. It could replace one old wired keyboard that I use which has the numerical keypad that I don't need, it just unnecessarily consumes the space.
I don't need the maximum light-output, this is why I wrote that I want light to go only through the letters, but not through the rest of the keys. I need just gentle, discrete lights to recognize with the peripheral vision which keys I am pressing in the dark. I am over 50, using computers since '80, but never learned to completely blind type, and I doubt I would ever do.