Question

why are periscopes are made in z shape? why not in other shapes?

Answer 1

There are not many applications for periscopes with different shapes.That is why periscopes are made in z-shape.If you are desperate you can make one on your on your own--- Its simple (Just browse the web)

Answer 2

yes , they can be made in other shapes like L shape or any other shape but it is Z shape that gives best increase in vertical height while other shapes may do the work but will change perspectives like horizontal length or inverted image