Ask for an experimental report: the function and operation of digital camera system

Composition and basic functions of digital camera

A typical digital camera has a lens cover in front to protect the lens. At the same time, it is connected to the power switch, and when it is used, it will be turned on to automatically add power. After opening the lens cover, the front is the lens part. This lens is a zoom lens. When shooting, aim the lens at the scene, and the image of the scene will be shot into the digital camera. There is a CCD image sensor behind the lens, which will turn the light image into an electrical signal for processing and then record it on the memory card. The flash part of a digital camera is used to illuminate the scene in the dark. On the back of the digital camera is its viewfinder, LCD screen and operation panel (control button). When shooting, you can get a better picture by observing the view through the viewfinder, and at the same time you can display the picture to be shot on the LCD screen. By observing the LCD screen, we can know the target of the scene to be shot. Because the LCD screen consumes a lot of power, in order to save electricity, we can turn off the LCD screen and observe the target directly with the viewfinder. After the target is selected, the shot scene can be enlarged and reduced by the zoom button located above the camera to get a suitable lens. Next to the zoom button is the shooting button, which is used to select the scenery and take pictures after adjusting the lens. On the side of the digital camera, there is a data interface, which can directly send digital signals to the computer for processing. Below the data interface is a memory card loading socket. After the memory card is loaded, digital photos can be stored on the memory card, and the memory card can be taken out to exchange or output data. The data interface, memory card socket and battery box of the digital camera are located next to the memory card socket. If you go out for use, you can put the battery directly into this battery compartment and lock the battery compartment. Pay attention to the use of batteries with good performance, because digital cameras consume a lot of power. There are two sockets on the other side of the digital camera. As shown in Figure 5, the yellow one is the video output socket, and the other is the input socket of DC power supply. This digital camera can directly use batteries or DC adapters. The video output socket and DC power input socket of the digital camera are schematic diagrams of the internal structure of the digital camera, as shown in Figure 6, and the composition of the digital camera can be understood through the internal structure. The front is the front panel of the digital camera. There is a lens cover on the front panel. This lens cover is used to protect the lens. Behind the front panel is the bracket and battery box of the digital camera. The schematic diagram of the internal structure of the digital camera is located in the lens cover, which is the lens of the digital camera. It has a zoom function, which can zoom in and out the shot scene, so it is also called zoom lens. Zoom is driven by a motor, and it also has the function of autofocus, which is also driven by a motor. There are two motors in the lens to control the zoom and focus of the lens respectively.

Coaxial with the lens is a CCD image sensor. When the scene passes through the lens, the image will shine on the photosensitive surface of the CCD image sensor, forming a small optical image. CCD image sensor is an integrated circuit, which converts optical images into electrical signals through synchronous driving signals, and then outputs them to signal processing circuits through output circuits. The signal processing circuit is mainly composed of digital image signal processing circuit, which is composed of many integrated circuits. This digital camera can shoot both still pictures and moving pictures, because it also has a video output circuit. There is also a memory on the main circuit board. The digital camera first stores the processed digital image in the memory, and then sends it to the storage medium (memory card). There is a media slot in the camera. When shooting, insert the memory card into the media slot, and the processed digital image information can be stored on the memory card through the interface plug-in. Pull the memory card out of the media slot and send it to the computer for processing. The work of the whole camera is completed by the control circuit. The main circuit in the control circuit is the microprocessor (CPU), which controls all components of the digital camera by receiving manual instructions on the keys. When taking an image, you can observe the image to be taken through the LCD screen on the back of the digital camera. At present, the LCD screens of digital cameras are relatively large, so it can clearly display the images to be shot, and can also be watched and selected by many people at the same time. In addition, the digital camera is equipped with an optical image viewfinder. The optical finder sends the image shot by the lens to the CCD image sensor, and at the same time, a part of it is separated by the reflector and sent to the viewfinder for the photographer to choose. In addition, the digital camera has a flash, a shooting function display screen and an operation circuit. The flashlight has its power supply circuit and is used when the subject is dark. The shooting function display screen can display the working state, shooting times and date of the camera. The operating circuit is located on the printed circuit board, which can convert the manually input key signals into electrical signals and then send them to the microprocessor in the camera. There are operation buttons on the operation circuit, such as zoom button, shutter and working mode selection button. Because the working mode selection key is rotary, there is a fan-shaped contact below, which can be rotated to different angles to select different functions.