Within the packaging range of the black ring, the environment is abnormal, but Zheng Yichen can't tell; his perception doesn't work on things outside the boundary.
Just by looking, there's too little information to confirm anything. To discover more, according to Tia's response, Zheng Yichen needs to actively break the black ring or come to a place outside the black ring to take a look.
Even if the concept of distance exists within the black ring, it doesn't mean Zheng Yichen can escape the world barrier to move around. When there's a point of reference, he can also gain a sense of distance outside the boundary.
Once he no longer contacts a reference point, even if he's just one micron away from the world barrier, that one micron distance would be infinitely magnified due to environmental chaos.
The world beneath his eyelids would instantly vanish, though Zheng Yichen himself has a sense of distance and wouldn't fall apart because of the outside environmental chaos.