Microlenses, thinner and lighter than traditional lenses, fabricated with high precision, can handle a wide range of angles and wavelengths of light.
MLA (microlens arrays) contains multiple microlenses formed in a one- or two-dimensional array on a supporting substrate.
Wafer-level optics is the design and manufacture of micro-öptics using techniques first devised for the semiconductor industry, attractive for their effectiveness; affordability, and scalability. With these techniques, anything from a single-element lenslet to a multi-element structure comprising millions of lenses, with precisely-aligned lens wafers bonded together and diced to form multi-element lens stacks.
Technology
An MLA-based projection assembly comprises an LED light source; collimator, and the MLA itself. The array is a custom-designed module; a typical MLA measures 11.4 × 10.7 × 3.0 mm.
The array is a precisely manufactured set of miniature lenses, or ‘lenslets’. As the lens array is fabricated through processes shared with the semiconductor industry, MLA technology benefits from the same cost and quality advantages that silicon chips enjoy. Nanoscale fabrication also means the lenslets can be precisely shaped and positioned so they project a single, sharply-focused image onto a surface—flat, curved, or freeform—at a specified distance and angle relative to the projector.
In automotive, micro-öptics are used in HUDs (head-up displays); in LED-based interior and exterior lighting; to improve the resolution and image quality of reversing cameras; in laser sensors for autonomous driving systems; in infotainment displays, and in manufacturing processes to ensure precision and accuracy in the production of car parts.
Prevailing Industry Consensus
Advantages of micro-öptics in automotive applications
Styling; possibility for black headlamp appearance; homogeneity; enables new functions; compactness (packaging space reduction; miniaturisation, weight reduction)
Disadvantages of micro-öptics in automotive applications
Investment and production cost; special expertise required; tight tolerances and difficult manufacturing processes; individual aperture calculations for each lens in array, relatively low efficiency.
Micro-öptics in production
Light curtains · homogeniser films and optics · colour correction and homogenising optics and lenses · welcome light carpet · projection module condenser lenses · ground projection modules · micro freeform optics · optic approaches for headlamps · micro-öptical features on primary optics and light guides · signal lights · rear lamps · DRLs · position lamps · headlamps.
Main reasons to use micro-öptics
Styling is the main reason. A lot of new applications like black appearance of headlamps when unlit; contour following light modules; vertical headlamps, and other new original designs stand to be enabled by micro-öptics.
Expected growth for micro-öptics applications in cars
Automaker demand for ground projections will push micro-öptics technology. Overall, over 10 per cent of all automotive lamps have the potential to use a microöptical component. The increasing demand for diverse, advanced solutions, as well as the reduction of production costs, is expected to drive the growth of micro-öptics in the automotive industry.
Future of micro-öptics in cars overall
The cost will be reduced by volume and technological progress, as usual in our business. A broadening supplier portfolio over the whole process chain will be the key. Micro-öptics will enable savings in materials, which increases the sustainability of the lamps; that’s becoming increasingly important. If micro-öptics become affordable, they will be widely adopted as a routine technology.
Applications
With ongoing advancements, we will surely see more and better applications.
Micro-öptics can do more than just act like bigger lenses. Their tiny size allows them to exploit the diffractive properties of light—think of a butterfly’s wings with microöptical surface structures which selectively reflect and refract light to create brilliant colours, and then imagine that kind of principle leveraged to create whole new kinds of lightstyles and visual signatures on automobiles.
