Nanning medical equipment lens

In the experiment, the farther the candle is from the convex lens, the smaller the image on the screen.

When the candle is close to the convex lens, the image will be enlarged and the image will be far away from the convex lens. The real image is upside down.

When the candle is in focus, it becomes an upright and enlarged virtual image, and no image can be obtained on the screen.

So, the answer is: small; Stay away; Fall head; Big; Focus.