One: just two magnifiers, the magnification of the objective lens is small, and the magnification of the eyepiece is large. This structure has a wide field of vision, easy to multiply and easy to find materials. But if you don't have a prism, it looks like it's upside down.

The other: a magnifying glass, with a small magnification, is an objective lens. A concave lens with a large degree is an eyepiece. Advantages, such as positive. Disadvantages-the advantages of the above methods correspond one by one.

However, conventional telescopes are quite complicated. In fact, it is not only the material, such as optical glass, but also the lens. If you are interested, you can look at/zhishi13 xiaosechajingpian.html, and you may understand that you can make the simplest one, but even so, it is just to experience the fun of doing it yourself, which is different from the real product.

This part of you is wrong, too. To turn an inverted image into a straight image, you need two prisms = =