Why do we have in a camera a 镜头)instead ofa simple hole?
The reason can be seen from the figures(图像).
In Figure 1, the hole is small. Rays of light from apoint (P1)outside reach a very small part of the wallopposite, and we see there a small point. But whenthe hole is bigger, as in Figure 2, rays from thepoint(P2)can cover a larger part of the wall opposite, and we don't see a clear point, Rays fromother points(Q) outside can also fall on the same place inside. Therefore the picture is not clearwhen the hole is big and it is not bright when the hole is small because very very little light canpass through it.We can get better result with a . If the is made in the shape shown inFigure 3, all the rays of light from the point(P3) are thrown on point(P') inside. The picturewhich we see, therefore, is clear, and it is also bright because more light can pass through a than through a small hole.Customized Flat Ground Or Roof Solar Mounting System Supplier free sample and its quotation and pricelist consultation, China Roof Mounting System manufacturers and suppliers，Welcome to buy our products.