The technology we choose is photography, and we are going to use a diagram to present it for the aliens.

The scene of taking photo is shown in the middle. In detail, there is a person standing, and another one standing in his lower right corner, holding a camera towards him.A dotted line starts at the screen of the camera and connects it with a square, in which there is a person in the same position as the person who is being shot. Everything in the square is just same as things around the model, which means that this is a technology that can record things vividly.

Then, we want to show them the tool we use to photograph. We use an arrow pointing the camera to the top left corner, where there are two bigger pictures of camera. One is complete, and the other one is a cutaway view, presenting under the complete one, in order to illustrate the inner part of a camera. Around the second one are some smaller pictures showing the structure and principle of some indispensable components, which are, the view finder, the shutter, and the pentaprism.

For the viewfinder, there is a line representing the light, and after crossing some lens, it was 90 degree reflected by a retroreflector and at the end of line there is a shape of an eye. It aims to show that thanks to the viewfinder, a photographer can check the view in the photo before taking a real one. The shutter is composed by a mechanical switch, a big gear, a smaller gear and a flap, and all these things are connected by three mechanical arm. When a photographer presses the shutter, it will drive the whole system, the mechanical arm will shrink and the the the flap will open. The pictures are presenting together with one’s flap open and the other one’s closed. As for the pentaprism, we want to draw its plane diagram, so that we can show how the light was reflected.

The right part of the diagram illustrates the core principle of photography，the puncture forming picture. There is a stick figure person standing to the right side, two arrows starting at his head and feet respectively, which represent the path of light. The arrows converge through one point until they get lens, which is drown a little behind the point, and they become two parallel lines. The lines reach the Charge Coupled Device and form an exact same image, except being inverted. This is how a camera works to catch a image.

Finally, in the blank part at the bottom of the picture, there are some example photos showing the genres of photography, arranged from left to right. The first one is some apples, which means Still life photography. The second one is a photo of a person, which is, undoubtedly, Portrait photography. The third one is Landscape photography, and the forth one, is an image that has been distorted abstractly, which means that there are some methods to modify a picture to achieve some art effect, which someone calls Art photography.

Since the aliens have a simultaneous mode of consciousness, we mean to avoid anything about time, so they won’t be confusing about the time line.