What's the name of this thing?

Question

Arduino

I want to turn on the light in my room when there is movement in the room, but I would not like to come in from the corridor, reach the middle of the room and then go blind from the light that suddenly turns on. It is necessary that the light turn on smoothly, so tell me what this thing is called with the help it was possible to implement a smooth turning on of the light,
I mean some kind of switch or module for arduino

Answer 1

lamp dimmer switch

Answer 2

dimmer
are sold in electrical stores, you can make a module based on it

Answer 3

The device is called a dimmer, but it can ONLY be used! with incandescent lamps (which are already exotic). Dimmers will not work with modern LDS or LED lamps and can damage them. There are LED lamps with a special ballast that allows the use of a dimmer, but such lamps are rare and significantly more expensive than conventional LED lamps. I met LED lamps with a built-in dimmer and a remote control for controlling brightness. You can use dual lighting: first, the LED strip turns on smoothly, and after a couple of seconds, the main lighting. You can also dismantle the LED lamp and replace the electronic balance with a homemade one.