Tlbimp.exe (Type Library Importer)
The Type Library Importer converts the type definitions found within a COM type library into equivalent definitions in a common language runtime assembly. The output of Tlbimp.exe is a binary file (an assembly) that contains runtime metadata for the types defined within the original type library. You can examine this file with tools such as Ildasm.exe.
https://github.com/dotnet/docs/blob/master/docs/framework/tools/tlbimp-exe-type-library-importer.md