Driver assistance systems are becoming the norm in the automotive industry and is becoming ubiquitous in the industry. One type of assistance system is the Head-Up Display or HUD, which uses a series of projectors, cold mirrors and beam splitters to project data onto an automobile’s or plane’s windshield. EMF recently won a large piece of business from the world’s leading automotive OEM distributor to supply cold mirrors for Head-Up Displays.
Head-Up Displays (HUDs)
A typical HUD contains three primary components: a projector unit, a combiner, and a video generation computer. The projection unit in a typical HUD is an optical collimator setup: a convex lens or concave mirror with a Cathode Ray Tube, light emitting diode, or liquid crystal display at its focus. This setup produces an image where the light is collimated, i.e. the focal point is perceived to be at infinity. Cold mirrors are often used as the concave mirror. Cold mirrors reflect visible light and allow the transmission of infrared radiation. These mirrors are used at an angle of incidence of 45°, thus reducing the temperature load from a light source by heat-light separation, which is important for applications where the light source is in close proximity to the mirror like in HUD.
The combiner is typically an angled flat piece of glass (a beam splitter) located directly in front of the driver, that redirects the image from the projector in a way that enables the viewer to see the field of view and the projected image at the same time. The computer provides the interface between the HUD (i.e. the projection unit) and the data to be displayed and generates the information to be displayed by the projection unit.
EMF – US-based Cold Mirror Manufacturer
Japanese auto manufacturers were still relying on Japanese suppliers for many of the technical components – like the cold mirror – even after moving their assembly operations to the US. So, they decided to identify a US-based manufacturer who could supply them cold mirrors in large volumes while maintaining the incredibly demanding delivery and quality requirements. EMF, with its 28 coating chambers and 40 million+ square inches of coating capacity, seized this opportunity and developed a new coating technology designed to meet the rigorous specifications of Japanese car manufacturers. EMF’s very first round of product met all quality requirements and was competitively priced. Consequently, EMF’s product was chosen by a top 10 global automotive OEM distributor to be the cold mirror of choice starting the 2014 model year. The breakthrough was based on technology derived from cold mirrors used in dental applications. EMF is one of the largest suppliers in the world of dental mirrors used in intra-oral photography. The mirrors are sold under the Riofoto brand.