Image: — © GETTY IMAGES NORTH AMERICA/AFP SPENCER PLATT
Technologists from the University of St Andrews (Scotland) have unlocked a step towards true holographic displays by combining Organic Light Emitting Diodes (OLEDs) combined with holographic metasurfaces.
Holographic metasurface are ultra-thin, engineered surfaces that manipulate light at the subwavelength scale to create dynamic, high-resolution holographic images.
Unlike the traditional one laser based hologramsthis new, compact and affordable method could transform smart devices, entertainment and even virtual reality. The innovation allows entire images to be created from a single OLED pixel, removing long barriers and pointing to a future of lightweight and miniaturized holographic technology.
Current and new holograms
Until now, holograms have been created using lasers, however researchers have found that using OLED and HM provides a simpler and more compact approach that is potentially cheaper and easier to apply, overcoming major barriers to more widely used hologram technology.
The potential of OLED
Organic light-emitting diodes are thin-film devices widely used to make color pixels in cell phone screens and some televisions. As a flat, surface-emitting light source, OLEDs are also used in emerging applications such as optical wave communications, biophotonics, and sensing, where the ability to integrate with other technologies makes them good candidates to realize small light-based platforms.
Progress
A holographic metasurface is a thin, flat array of tiny structures called meta-atoms – roughly one-thousandth the width of a human hair – designed to manipulate the properties of light. They can make holograms and their uses include various fields, such as data storage, anti-counterfeiting, optical displays, high numerical aperture lenses – for example optical microscopy and sensors.
This, however, it is the first time the two have been used together to produce the basic building block of a holographic display.
The scientists found that when each metaatom is carefully shaped to control the properties of the light beam that passes through it, it behaves like a pixel of HM. When light passes through the HM, at each pixel, the properties of the light are slightly modified.
As a result of these modifications, it is now possible to create a pre-projected image on the other side, utilizing the principle of light interference, where light waves create intricate patterns when they interact with each other.
Consequently, holographic metasurfaces are now one of the most versatile material platforms to control light. The new research offers a breakthrough that will enable a step change in the architecture of holographic displays for emerging applications such as virtual and augmented reality.
A metasurface is a extremely thin, artificially created two-dimensional material designed to control electromagnetic waves by manipulating their phase, amplitude and polarization on subwavelength scales.
This means that the new research provides a path to a miniature and highly integrated metasurface display. research features in the journal Light: Sciencewith the paper titled “OLED Illuminated Metasurfaces for Holographic Image Projection”.
