Hi, fellow physics friends! I'm doing a small interior decoration project in which I need optical image rotation as a component. I know that this can be done (see e.g. http://www.optics.arizona.edu/optomech/papers/swift%201972.pdf [Broken] for a review paper). I've also seen Half-Penta Prisms sold online that do this. However, a 25mm HPP costs $135. I want one which is about 1 meter in size, but on the other hand I have very low requirements on quality (a bit of optical disturbance is just positive) and the image need not be rotated 45 degrees (less or more is fine). Question: is it realistic to attempt to construct one myself? How would I go about to do this? I do have access to a small engineering lab at my local university. What material would you recommend? Note: The project is not to construct a death star with a death ray with which I can destroy planets insolent enough to defy my imperial will.