OLED and AMOLED the next generation of Automotive Visual and Display Technology: from flat screens to 3D and bendable touch surfaces
article review: Raffaele Schiavullo
Next trends of the in-vehicle displays
Consequentially the need to have performing interactive displays extremely responsive to touch and visual stimuluses, it has become a key feature to implement for all the players in the automotive industry.
The use of display technologies within vehicles is still experiencing evolutionary changes and new designs and functionality are being developed and integrated within the car systems all over the world.
The ongoing reaches are targeted to improve the equipment efficiency in terms of single and multi-touch responsivity to allow the driver a more “human centric” interaction with the driving experience: some companies like the Canatu and Continental have in place a joint venture to introduce on the market 3D touch surfaces displays based on a thin films and sensors technology, with the intent to replace the standard flat screens.
At same time the Visteon has developed displays base on a cold-formed technology with an HD haptic feedback, declaring them as the next frontier of the infotainment interaction for the automotive industry.
OLED versus LCD technology:
pro and cons
According to a report by Beyond HMI (Expert Company) the number of cars with center stack display will increase from 25% to 50% within the year 2012 to 2020 with the dominant technology of the future being the Organic Light Emitting Diode (OLED) technology.
The OLED technology is used to produce thin, transparent and highly responsive light displays panels. At first the dominant technologies for display technologies was the Liquid crystal display technology (LCD). Comparing the LCD and OLED technology it can be seen that OLED had the following advantages:
- OLED displays can produce perfect black images by turning off individual pixels meanwhile in LCD’s the screen does not deem uniformly: some parts dim independent of others.
- OLED displays have a better contrast ratio. This is because they have the feature to shine bright and form perfect dark effects. Since a good contrast is regarded as a function of brightness and darkness, OLED displays offer a better contrast as compared to LCD’s.
- OLED displays have better consistency of brightness as compared to LCD.
- OLED displays are “physically” more flexible and adaptable as compared to LCD’s, consequentially they are more adaptable to be used for bent surfaces.
Due to the above reasons most original equipment manufacturing (OEM) companies largely adopt OLED display technology as their technology of choice for the production of Automotive Visual and Display Equipment (AVDE).
OLED in detail: PMOLED and AMOLED
Focusing more on the OLED display technology, it is divided into two macro categories:
Passive Matrix Organic Light Emitting Diode (PMOLED)
This technology works by illuminating each row of pixels in the display screen sequentially. The Pixels of PMOLED electronics do not contain storage capacitors that can store electric power. This makes the pixels in each line to go off most of the time except when powered with the appropriate voltage. In the absence of enough voltage power they will be less brightness.
Active Matrix Organic Light Emitting Diodes (AMOLED)
AMOLED display technology connects a thin film transistor (TFT) to individual pixels in order to control the flow of current. The TFT has as main advantage that it can activate each pixel quickly.
TFT contains storage capacitors that maintain the state of each pixel when in contact with an appropriate power supply: this high level of control exerted on each pixel enhances screen resolution, contrast and gives a vivid display, providing an exceptional viewing experience. By AMOLED technology can be produced bigger and larger displays than by PMOLED, maintaining at same time an high quality resolution while responding rapidly to commands and instruction.
Adapting OLED technology into cars of the future
OLED technology is no doubt the future of AVDT and major car part manufacturing companies like Mercedes, LG display, OEM Cadillac, Tesla have unveiled several prototypes of future cars adopting that technology because of the following advantages:
- OLED technology provides vivid and unbreakable lighting display panels that can effectively be used as car display devices.
- OLED panels can be made to be slim and transparent. This gives birth to whole new world of smart application where by display features can be made to appear on transparent screen.
Statistics reveal that AMOLED displays are playing a key role into the AVDT due to efficient integration factors such as:
- AMOLED devices are bendable (have the ability to bend depending on the design): this means they can be effectively shaped and placed on different parts of the car.
- AMOLED devices have a better contrast ratio as compared to PMOLED.
- When used within car systems AMOLED display devices have quicker respond time.
- Due to a superior image quality of AMOLED devices, they can be trusted to offer a better display performance especially when displaying data from outside the car.
Despite the above pros, this seem to be the main cons for the AMOLED devices:
- Over time the color of some AMOLED panels can shift.
- These Panels are susceptible to high temperature.
- Since TFT LCD panel prices are dropping quickly over time, AMOLED display cars are still very expensive.
Application of OLED display technology in major car manufacturing companies
In mid 2018 Audi unveiled its newest car model the E-Tron Quattro that has 7 inch OLED Monitors connected to its rear view cameras. These Cameras shall replace conventional side mirrors in Audi vehicles. This technology provides different angles and views that can be displayed on OLED powered screens inside the vehicles.
Continental car manufacturing company has also introduced a similar technology like Audi where by side mirrors are replaced by Rear view cameras connected to Organic OLED monitors.
LG designed Flat curved plastic-based OLEDS for the original equipment manufacturing company (OEM) Cadillac, Tesla and Mercedes.
In the year 2016 Samsung developed flexible and transparent OLED car equipment that can be used by car manufacturing companies, introducing a rollable curved central information display (CID) system for automotive. The Samsung CID system has GPS, internet surfing services, music players and responds to very light touch and at same time it can be stretched from 9 to 14 inches. Samsung also introduced a glass free 3D display feature OLED technology that helps to increase the way driver recognizes essential driving information using 3D live imagery.