A Digital rear-view mirror is a camera-based mirror system that has been considered as an alternative to the conventional automotive rear-view mirrors.
Mirrors are essential for vehicle safety. However, traditional rear-view mirrors have drawbacks such as severe glare, a limited field of view, susceptibility to damages, and aerodynamic drag.
Cars with digital rear-view mirrors deliver a smooth and seamless driving experience coupled with enhanced safety, comfort, and convenience.
With the advancement of technology and continuous evolution of automotive parts, the digital rear-view mirror has been welcomed as a highly useful alternative. The installation of the camera at the rear side of the vehicle provides an excellent observation point with exceptional visibility.
The enlarged field of vision offered by the camera enables the driver to easily detect objects located behind the car.
Components of a Digital Rear-View Mirror
Majority of digital rear-view mirrors are a combination of a camera mounted at the back of the car and the conventional rear-view mirror, working together as a unit. The conventional rear-view mirror also acts as a screen in most cars, whereas in others, there is a separate screen that broadcasts the image captured by the camera.
A new technology called the camera monitor system or CMS has been incorporated with the traditional rear-view mirrors to provide camera-captured images on in-vehicle displays. The captured image is digitized and displayed in the screen inside the car. In-vehicle digital rear-view mirror displays are less vulnerable to extreme weather conditions as there is no direct contact between the two.
The cameras transmit a very low-latency image to the car's OLED touch panels. The image sensor's improved dynamic range ensures flawless image quality in any weather or lighting situations. Furthermore, the driver can easily adjust the cameras manually from the screens. With a simple click on the screen, the digital rear-view mirror can be adjusted to view higher or lower, left or right.
Electro-chromatic Rear-View Mirrors – A Revolutionary Technology Backing up Digital Rear-View Mirrors
Some cars have digital rear-view mirrors that come with a technology of image sensors. An image sensor comes in very handy when other vehicles directly project their headlights on the windscreen.
Since a digital rear-view mirror runs as a display from a camera, it’s feed can be processed according to the preference of the driver. Be it reduced glare, or automatic adjustments to contrast, a digital rear-view mirror comes with all kinds of functionalities.
Recent innovations have helped build these electro chromatic digital rear-view mirrors, that come with the auto-dimming technology. Auto-dimming mirrors function on the principle of electro-chromism. These smart rear-view mirrors have light sensors that automatically dim the mirror’s glare as per the driver’s requirement.
Working of Electro-chromatic Rear-View Mirrors
Electrochromism is the colour alteration that occurs in a substance on application of electric current. The alteration is reversible. An electrochromic rear-view mirror dims automatically when it detects light from behind the vehicle, decreasing glare.
The mirror is manipulated electronically, with light sensors and a unique gel that changes colour when an electric current causes it to gain or lose electrons.
A sensor detects low ambient light from headlights behind the vehicle and prompts the rear-view sensor to look for glare in auto dimming mirror technology. The mirrors darken automatically in proportion to the intensity of the glare, then clear when the glare is no longer detected. During fabrication, an electrochromic gel is sandwiched between two pieces of glass that are etched with an electrically conductive coating.Â
This technology guarantees the correct amount of dimming at any given time.
Let’s have a look at some of the advantages of a digital rear-view mirror:
Improved Vision – With advanced CMS and high-definition cameras, digital rear-view mirrors provide a wider view. The conventional rear-view mirror has a larger region of blind spots. Fortunately, the digital rear-view mirror significantly reduces the number of blind spots when driving. This has a huge benefit when changing lanes or crossing junctions!
Since the camera is mostly located above the license plate, digital rear-view mirrors offer at least a 100° field of vision. As a bonus, they also capture the lower region behind the car. The image vision extends to a point that is very low as compared to a conventional rear-view mirror. This feature lets the driver have a clear idea of the objects behind the vehicle while reversing. Since these mirrors are effective in low light as well, they provide better parking perfection.
Scalability – The set of features laid down by ADAS, can scale in conjunction with the functionalities of digital rear-view mirrors, i.e., up to ADAS Level 2 functionality.
Versatile Nature – A digital rear-view mirror functions perfectly in all weather conditions. Since the camera is mounted outside the vehicle, it can display a clear image of the road. This is possible even on a foggy or rainy day because of high-end-heated camera functions. However, these mirrors might get in direct contact with rain or snow or fog. But as they process the image digitally on a different screen, the visibility remains unaffected.
Enhanced Safety – The safety factor comes as a result of better vision and versatility. These new age mirrors give a more comprehensive perspective of what’s going on behind the car. Digital rear-view mirrors play a vital role in ensuring safety by calculating the distance between vehicles and providing a good estimate of how much distance should be maintained.
- Improved Ergonomics – Since a digital rear-view mirror provides a well-defined set of functionalities, it suits all driving conditions. A conventional rear-view mirror may not serve its purpose if there are any obstructions that block the view from inside the vehicle. This issue is mitigated by a digital rear-view mirror. It minimizes the strain on both driver and passengers, ensuring comfort while driving.
Points to Note
Digital rear-view mirrors can be operated in digital mirror mode or optical mirror mode. There is usually a lever on the system that enables the change in modes.
Depending on the user’s age or physical condition, they may be unable to focus on the image displayed in digital mirror mode. In that scenario, the user can always change to optical mirror mode.
It is not advisable for passengers to stare at the mirror while it is displaying an image in digital mirror mode. In some circumstances, this can result in motion sickness.
Digital Rear-View Mirror Protection
Digital rear view mirrors tend to dissipate heat when operating in digital mirror mode. To mitigate excessive heat production, e-mirrors come with in-build thermal management systems that protect printed circuit boards and other sensitive components.
They are also integrated with cushioning and damping technologies to protect against shock and vibration, that may otherwise result in flexing or cracking of the mirror.
Drivers should periodically clean the mirror and the camera to ensure that the e-mirror works in prime condition. The mirror surface can be cleaned using a soft dry cloth. The camera lens can be washed with water and then wiped clean with a soft damp cloth.
Conclusion
Digital rear-view mirrors are the future of commercial and personal vehicles. Although the cost factors of installing them on a large scale might look daunting, the technology behind these mirrors is a blessing.
With an all-round set of enhanced features and ADAS – L2 functionalities, digital rear-view mirrors ease the entire driving process, making it more comfortable and effortless.
Based on recent market research reports, Europe will account for a major share of the global e-mirror market between 2021 and 2031, as this region is witnessing a huge demand for comfort features in vehicles. Asia Pacific will also hold a decent share of the digital rear-view mirror market owing to increased production of vehicles in this region.
