The TARDIS is en route to Gallifrey, but accidentally passes through a portal into another universe called E-Space. After landing on the planet Alzarius in E-Space. the screen shows a picture of Gallifrey rather than Alzarius which is really outside. This is nonsense. The scanner can only depict a live image of what is outside the TARDIS, not something that is in another universe. The fact the Doctor then searches for a "local image translator" component for the TARDIS to show an accurate image is simply a lame plot device to give the Doctor something to do.