I've just made this:
https://mods.factorio.com/mod/TilePrototypeViewer
Plz add this feature into gvv. Thanks.

Sorry. This is a global variable viewer, not prototype explorer.
Reason why this mod have a function to show prototypes is that "game" is a global variable.

Factorio already have a built-in prototype explorer. I think default hotkey to open prototype explorer is Ctrl+Shift+E.
There is a section for tile prototypes in that explorer.

OK, it doesn't matter.

But, it looks not so difficult and not requires big changes, so i implemented it from 0.3.5

The reason I came to mention this, is that, both your tool and vanilla tool don't have a way to show how the tiles look when they are on ground.
By the way, I don't know how to code static text. I tried a slow way. It works, but it's never the best way. Any idea?

https://github.com/x2605/gvv/blob/v0.3.6/modules/sprite.lua
This may be an example for you. My source code to get image from prototypes.
If given object is LuaTilePrototype and its name is "dirt-1" then
Sprite.img(object) will return a string "[img=tile/dirt-1]".

You can print image on screen using a richtext format.
https://wiki.factorio.com/Rich_text

https://github.com/x2605/gvv/blob/v0.3.6/modules/sprite.lua
This may be an example for you. My source code to get image from prototypes.
If given object is LuaTilePrototype and its name is "dirt-1" then
Sprite.img(object) will return a string "[img=tile/dirt-1]".

You can print image on screen using a richtext format.

Ohhh, this is great. Thank you very much.

https://wiki.factorio.com/Rich_text