A backup camera (also called a reversing camera or rear-view camera) is a special type of video camera that is produced specifically for the purpose of being attached to the rear of a vehicle to aid in backing up and to alleviate the rear blind spot. It is designed to avoid a backup collision. The area directly behind vehicles has been described as a "killing zone" due to associated accidents. Backup cameras are usually connected to the vehicle head unit display. A common variant is a Surround View system, which assembles a synthetic but positionally accurate top-down view of the vehicle and its adjacencies.
Backup cameras have been regulated by law in Canada and the United States since 2018. Backup cameras are becoming increasingly common on vehicles and as of May 2018 they are required on all new automobiles sold in the United States.
Function
The design of a backup camera is distinct from other cameras because the image is horizontally flipped so that the output is a mirror image. This is necessary because the camera and the driver face opposite directions, and without it, the camera's right would be on the driver's left and vice versa. A mirrored image makes the orientation of the display consistent with the physical mirrors installed on the vehicle. A backup camera typically utilizes a wide-angle lens or fish-eye lens. Although such lenses may limit the camera's ability to capture distant objects, it allows the camera to see an uninterrupted horizontal path from one rear corner to the other. The camera is typically pointed at a downward angle to view potential obstacles on the ground.
Backup cameras make use of dashboard screens that are also used with GPS navigation systems. Inside the vehicle, the display is typically wired to automatically sense when the transmission is set in reverse, showing the backup view on the dashboard screen while the vehicle is in reverse and/or providing grid guidelines by detecting the parking lot markings to aid the driver.
Variations
Backup cameras are produced in different varieties depending on the application. Backup cameras can be added as aftermarket additions to vehicles that do not come with factory-fitted systems. They are available in both wired and wireless versions. For large vehicles such as motorhomes, camera systems with built-in servomechanisms allow the driver to remotely pan and tilt the camera. Wireless Backup Cameras come with a wireless camera and receiver, which make it easier and cheaper to install them. Built-in audio intercoms (one-way or two-way) are used in addition to the camera system for communicating with a spotter outside the vehicle - common when backing large trailers or launching boats. Night vision cameras use a series of infrared lights for backing in the dark, when the positioning or the intensity of the vehicle's white reverse lights are insufficient for this purpose.
Portable or semi-permanent all-in-one camera systems, also known as dashboard cameras or dashcams, are typically sold for vehicles that don't have displays permanently installed in the dash. Such systems consist of a small portable screen that can be affixed on the dashboard or on a rearview mirror, and a length of wire to reach the cameras, including a backup camera. Some backup and rear cameras are connected to displays on the rearview mirror and are used in vehicles to detect activity behind the car to "avoid the tooling, software, hardware, and testing costs associated with integrating the display/feature in other areas of the vehicle." License-plate-frame versions permit installation without any permanent vehicle modifications. Custom cameras: brake light cameras are combination devices that contain a camera, while still illuminating as a brake light. Some backup cameras also use a combination of LEDs surrounding the camera lens to illuminate the surroundings while in use.
History
The first backup camera was used in the 1956 Buick Centurion concept car, presented in January 1956 at the General Motors Motorama. The vehicle had a rear-mounted television camera that sent images to a TV screen on the dashboard in place of the rear-view mirror.
Later the 1972 Volvo Experimental Safety Car (VESC) had a backup camera. However, the camera did not make it into the following Volvo 240 model.