No more looking down! ADAS gives rise to head-up display technology

Nowadays, more and more models are equipped with head-up display (HUD) systems as standard. HUD can project information such as current speed and navigation onto the photoelectric display device on the windshield, forming an image in front of the glass. The driver can see relevant information without turning or lowering his head, greatly improving safety.

Among many models, the Lincoln Continental's HUD system has a display effect that is superior to its peers, thanks to the DLP chip with 400,000 micro-mirrors that can work at a frequency of 5,000 times per second. The display size is larger, the brightness is higher, and the content is richer. Depending on the driving mode, this HUD head-up display system will also display different information. For example, in sports mode, it will provide information such as engine speed and speed.

HUD rises with ADAS

The rise of HUD is entirely accompanied by the maturity of the ADAS market. In the future, as ADAS provides more lane departure warnings or collision avoidance warnings, the best display space for this data is on the front windshield, so this gives the HUD market huge room for imagination.

The early HUD display technology had a viewing angle (FOV, Field of View) of less than 4°, a single color, and very limited display data. The current HUD viewing angle has increased to 7-8°, which can provide more data display, but it still serves as an auxiliary display.

When the FOV increases to more than 12° in the future, it will be able to provide more AR functions, with brighter and more saturated images, while supporting a virtual image distance of up to 20 meters. It can carry more ADAS-related data and can even be used as a primary display screen that is as important as the dashboard.

TI DLP technology enables HUD to continue to develop

The automotive market is the hottest application field nowadays, and TI DLP technology is being tried in the field of AR HUD head-up display. TI has been introducing DLP automotive chips to the market since 2015. The latest products are smaller in size and have a larger viewing area than previous generations, fully meeting the AR HUD scenario.

DLP technology is the brightest HUD display technology on the market. It also supports the largest viewing angle and supports wearing polarized glasses. In 2017, the Lincoln Continental became the first mass-produced car equipped with DLP HUD technology. Although it was not an AR HUD at the time, it was much better than other HUD systems on the market. Today's latest models have begun to use AR HUD technology, and the experience advantage has been further improved.

The difficulty in increasing the visual range is that the HUD is placed in front of the dashboard, which will encounter the problem of sunlight exposure. The larger the visual range, the smaller the focus, and stronger emission energy is needed to overcome the influence of sunlight backflow, which puts higher requirements on the temperature resistance of TFT and lens, and it is easy to be damaged. DLP does not have this problem, so it can provide a higher visual range and brighter images.

In addition, operating temperature is very critical. When you are in an environment with a brightness of up to 15,000 nits, including outdoor environments, or when your cab environment is hot, it must be able to support stable operation. Therefore, TI's latest AR HUD technology has increased the vehicle temperature requirement to 105°C.

For HUD application scenarios, it is best to have a consistent user experience regardless of day or night, winter or summer, or when traveling in the desert. Because DLP does not use polarized light projection technology, it supports drivers viewing the device while wearing sunglasses.

Click here to quickly view the TI DLP technology zone and view its latest information on HUD.