No real solution. You can't get rid of glare on a TV and it looks like the one you have already has some glare reduction applied to the surface to help diffuse the glare. I think there are some additional diffuser filters available out there, but once again, it diffuses the glare, it won't eliminate it.
Curtains are always one of the better solutions to deal with glare. You can use light filtering versions to cut light, but the reality remains that dark scenes, during the day, have been, and always will be, problematic.
You can rotate the TV some so that it is pointed more towards the viewer, rather than the windows. Get them out of the line of sight as an option as well.
No perfect solutions unfortunately. This is something I deal with in my family room as we have a lot of windows to deal with. Mostly, we try to watch brighter TV shows during the day where reflections in the TV don't impact the image nearly as much. If we watch something with darker scenes in it, then we sometimes retreat to the basement which is fully light controlled.
