Sorry pinball people, but I will post a pinball related post next. This is another slot concept of mine.
The current technology of video monitors allows the screen to become transparent, so that you can see through the screen. IGT currently uses this technology to create their 3D effects by having two monitors (MLD), one behind the other, that have offset content. The front layer can be transparent, so that you can see the content on the rear layer.
With this in-mind, my concept is to only have one layer, which always has no see-through areas, looking like a standard video monitor when being played. But we can make the reels disappear and reveal a hidden diorama. This diorama has a physical device, such as a wheel, bagatelle, roulette wheel, etc. which is used for playing bonuses.
Here is a fictional example, in this example, the bonus is a “Sigma Derby” type race. So if you earn a bonus, then you could choose between “Free Spins” or “Derby Race”. If you choose Free Spins, then you would be awarded standard free spins and would never see the diorama, however if you choose the race, then the reels go away and internal lighting comes on, revealing the diorama. You would choose your horse(s) and then the race would play out. When the race is over, the diorama would be hidden and a math screen would show you your total.
Standard Slot Screen Hidden Diorama revealed