2. Fix the convex lens at the front end of the cylinder (tape paper);

3. Cover the end of the cylinder with transparent paper (adhesive tape paper);

4. Note: Finally, the convex lens and transparent paper in the overall shape of the device are like the cover of the cylinder, but they can't be opened;

5. Use: point the convex lens at the scene, and when the transparent paper points at you, your eyes will look at the screen (transparent paper), so that you can see the scene on the screen.

6. note: it is best to have bright scenery and dark light where you are.

Original.