The field of view angle of a lens is an extremely important parameter. The field of view of the lens changes with the focal length of the lens and the size of the camera (the relationship is as mentioned above). The focal length of the lens covering the scene can be calculated by the following formula: (1)f=u? D/U (2)f=h？ D/H f: focal length of lens, u: actual height of scene, h: actual width of scene, d: measured distance from lens to scene, u: image height, h: image width.
A lens of 3.6mm can barely be called a wide angle, and lenses of 6, 8, 12mm are not counted.
Extended data:
Camera or webcam, also known as computer camera, computer eye, electronic eye, etc. , a video input device, is widely used in video conferencing, telemedicine and real-time monitoring.
The camera collects images through the lens, and the images are processed and converted into digital signals that can be recognized by the computer through the photosensitive element circuit and control elements in the camera, and then input to the computer through the parallel port or USB connection, and then the images are restored by software.
The image sensor of a camera can be divided into two categories: CCD (Charge Coupled Device) and Charge Coupled Device. CMOS (Complementary Metal Oxide Semiconductor): Complementary Metal Oxide Semiconductor.
References:
Camera Baidu encyclopedia