Liquid crystal lenses, a revolution for optics
Every day we face work and family tasks to the best of our ability, supported by certain high-tech aids that are essential to achieve a thousand and one goals. We have now become familiar with concepts such as liquid crystals, which identify an intermediate state in which matter finds itself: we are between a crystalline solid and a classic liquid. The properties that this dual nature assigns to liquid crystals are many and range from fluidity and aptitude for the formation of droplets through typical properties of crystals: elastic, optical and magnetic.
The technological applications of liquid crystals – discovered in 1888 by the Austrian botanist Friedrich Reinitzer – to which we are accustomed in our daily lives are different, just think of their presence in the LCD (liquid crystal display) screens of the televisions that populate our homes, but also in those of tablets and smartphones, real all-rounder assistants. But science never stops and indeed is constantly looking for new ways of development, in a tension towards the future and innovation. This is why the combination of lenses, glasses and liquid crystals appears on the horizon, ready to undermine the traditional leadership of glass.
Technological lenses, here’s why the cards on the table change
For centuries, man has learned to shape glass and refract light by creating lenses, perfect for defining, amplifying and correctly focusing images and objects near or far, effectively supporting eyesight. In recent years, however, a group of researchers from Harvard University has made great strides in the field of optical science by managing to engineer flat optical surfaces using millions of transparent and very thin quartz micro-pillars.
The latter are able to distribute and shape the flow of light exactly as the ‘classic’ glass lenses do, but net of all those defects that generally limit the use of this material. Being able to reduce the size of the lenses used by smartphones, tablets and other electronic devices is a goal that goes beyond the normal methods of cutting and bending glass. Technological lenses could supplant the current ones made of glass, allowing, for example, the concrete miniaturization within sensors and devices for diagnostic imaging in the medical field, but not only.
Optical engineering and developments for the future
We are talking about revolutionary metalents, which can be concretely reconfigurable. Important steps forward also with regard to the future of prescription lenses, since liquid crystals can be shaped thermally, magnetically, electrically or optically. This will allow you to make flexible lenses.
A real revolution is therefore looming on the horizon for the world of optics, which we have come to know in a certain way from the sixteenth century onwards. The use of metalents opens a new front for wavefront engineering, since the amplitude, polarization and phase of the light can be controlled. The ‘reconfigurable light’ is therefore a decisive step in the field of optical science, which is based precisely on the key element of liquid crystals.
