讲座内容:

    The talk will present the development of a few micromirrors with applications in automotive Head-up Display (HUD), laser pointer, laser marking/engraving/etching.  

HUD displays critical driving information such as driving speed and navigation information floating ~2 meters ahead of the windshield. The display and projection module is installed under the dashboard with the size of 4 liters and price of USD1000 ~1500. The HUD enhances driving safety/comfort and is equipped in luxury cars.  In order to reduce the HUD cost to and enable middle and low end cars to enjoy its benefits, a combiner type of HUD appears in recent years which is installed on the dashboard and the floating image is seen through a transparent concave mirror. It cost a few hundred dollars and can be as before or after market device. The limitations with the current HUD technology is the short projection distance, i.e., 1~2 meters from the windshield and low visibility in the strong sunshine. Consequently the driver needs to refocus eyes from the road to the HUD image since the eyes’ focus is normally on the road during driving which is about > 10 ~ 20 meters ahead of the car.  The talk presents a novel micromirror laser HUD technology, which can achieve a projection distance of HUD image of 20 ~ 30 meters with high visibility in the sunshine. Furthermore the core technology, i.e., micromirror, is fabricated using commercial and mature microfabrication technology and therefore its cost is only 1~2 USD. Thus the cost of the miromirror laser HUD is of USD 20 ~ 30.

Conventional MEMS micromirrors are normally fabricated in a clean room through microfabrication technology. In order to achieve a large aperture (>1 mm) and high flatness (radius of curvature, ROC> 10 meters and nanometer roughness), the cost of such a MEMS micromirror is of 10s dollars, which is low and acceptable to some applications such as medical devices. However, it cannot be acceptable for a lot of consumer electronic devices with the price of a few dollars to tens of dollars such as laser pointer. This talk presents a novel micromirror technology, i.e., FPCB (Flexible Printed Circuit Board) micromirror, which can achieve high surface quality (ROC>15 meters and roughness of nanometers) and large aperture (1~4 mm) and low cost of < USD 1. This FPCB micromirror has been successfully applied to laser pointer, availability indicator and laser marking/engraving/etching systems.