You may have an IGT Vision machine and could very well need a new invertor ballast to light up the screen.
They're nowadays
beyond expected lifetime.
The Vision platform is well over 20-25 years old now.
If I were you, I'd open up the LCD unit removing the back cover plate exposing the circuit board, and place a plain jane computer jumper across JP1.
The two pins are located behind the memory sticks at JP1 on the extreme lefthand side of the circuit board.
Then turn ON the machine, turn OFF the lights in your room and shine a flashlight upwards upon the LCD panel.
If you see lettering and graphics, the invertor ballast could be burned out or the fluorescent lighting is dead.
Cheapest possible fix is to get a replacement ballast
LS520A inverter board.
Here's a link...>>>
https://www.ebay.com/itm/297613062127