Is there big screens to magnify a show, a football game etc.

I am looking for a glass to enlarge the view for the viewers (visitors) seated in the back rows and seats, say in a theater or a ball game. Does this technology exist?

Not 100% sure what you're asking here, so I may need you to clarify. Are you asking if there are large screen TVs or large screens for projectors? If so, yes there are. And you can get TVs pretty large, if you have the money. Keep in mind though that you will be enlarging the same resolution image which, unless you are sitting an appropriate distance away, will look bad.

If you are wondering if you can purchase a magnifying panel to go over the screen to make the image appear larger... I'm sure someone has made something like that (I remember seeing them for the Game Boy haha). I'm not aware of any, and just thinking about what that would do to the picture makes me dizzy. Not to mention the possible damage to your eyes from magnifying the light given off by the TV.

https://www.askmehelpdesk.com/home-electronics/magnifiers-theater-611777.html

I see now that you were probably asking about some form of magnification and not a larger screen.

The simplest solution is to have people seated in the back switch with those up front if they have trouble seeing. I don't recommend using any form of magnification on any kind of light source (ie a TV).

If a person if having troubles seeing a screen from the back of a standard movie theater, they need to see an eye doctor to get their eyes checked out. If this is not a standard movie theater, and you are trying to set up a room like one, then you might not have the right size screen for the seating distances.

If at a sporting even, one can use binoculars.

I need to separate two big rooms by a glass. Could it be a magnifying glass for bigger view. It should help the people in the back room to view the stage (which is in the front room) more clearly, and to see more details.
Would the view be reasonable, nice and clear, using available technology.
Note: people in the back room will be moving forward on a very slow travellator. People in the front room will be walking

I guess I'm confused as to what exactly you're doing. Why are people moving? Why separate the rooms at all? What distance are we talking about? What size screen is this?

This sounds more like some kind of an art exhibit than a theater.

Also, please only give negative ratings for factually incorrect answers. I was as helpful as I could be and gave you TONS of information. I am being as helpful as possible with the limited information you gave. You never mentioned in your original post that you needed to separate rooms or that people are moving. It just sounded like you wanted a bigger screen or to make a screen look bigger.

People enter from one end and exit from the other.
The separation is to avoid congestion. In the front room , or hall way ( existing), people will be walking on their foot. While, I am considering travellator in the new extension, to accommodate more people, and to organize, etc.
The width of the front (existing) room, that is affecting the back room, is 10 m. However, the extension is planned in stages, and could reach greater widths to accommodate more and more people. Full width of the extension is 24.2 m
The length of the separating glass (perpendicular to width of room),is 30 m. The height could extend up to 9 m ( maybe I will reduce it to 5.0 m).
The set-up can be described as an art exhibit, I agree.

This is the glass that I am looking to see if it can be a magnifying glass

People enter from one end and exit from the other.
The separation is to avoid congestion. In the front room , or hall way ( existing), people will be walking on their foot. While, I am considering travellator in the new extension, to accommodate more people, and to organize, etc.
The width of the front (existing) room, that is affecting the back room, is 10 m. However, the extension is planned in stages, and could reach greater widths to accommodate more and more people. Full width of the extension is 24.2 m
The length of the separating glass (perpendicular to width of room),is 30 m. The height could extend up to 9 m ( maybe I will reduce it to 5.0 m).
The set-up can be described as an art exhibit, I agree.

Please see attachment

That helps out a great deal with understanding what you are looking for. I know of no company off the top of my head that has something like that readily available, nor do I know of a company off the top of my head that can produce something like that.

Sounds like you are basically looking for a one-way mirror that also uniformly magnifies.

If I come across a company that might be able to do something like this, I'll either direct them here, or give you the information. Otherwise, I wish you luck in finding what you need. :)