Here is an idea for a porthole where the structure of the habitat does not allow to install one. For example on the ceiling, where penetrations of the shell should be strictly avoided in order to maintain the integrity of the emergency safety area in the upper part of the living area. The Virtual Porthole would consist of a camera on the exterior of the shell and a TV flat screen on same position inside the habitat. This solution would have different advantages:
- maintaining a wider view area by using a camera with a wide-angle lens imitating a bubble-type observation port
- infrared view in the night
- the screen is temporarily removable, therefore a foldout porthole
- live view sent to the land station or support vessel
On the other hand it is a disadvantage that we would have one more device to use electric power. Therefore the virtual porthole should be turned off while not in use.
Well, there are news, that flexible screens used like wallpapers will be available soon. If so, this screen could follow the curvature of the desired position (e.g. the ceiling). An XL size screen is also imaginable, glazing big areas of the ceiling or a wall without to penetrate the shell and disturbing the static integrity. For that purpose maybe more than one camera might be installed and their images combined.
What do you think?