Future VR headsets may use a new type of lens inspired by holographic technology.

Future virtual reality (VR) headsets could use a new type of lens inspired by holographic devices, researchers say China say. The proposed new type of bifocal lens can switch between one focus and another with the flick of a switch, allowing wearers to watch the lenses’ intensity change, similar to a hologram.

These lenses will consist of two layers of liquid crystal structures that can switch between two focuses using an external voltage. The researchers described their findings in a new study published Oct. 1 in the journal. Optics Letters.

According to the team, the technology could be applied to imaging devices, optical computing, and optical interconnects—in addition to future mixed reality and VR headsets.

In particular, they can be used for polarization imaging—often used to enhance the contrast of an image or to render edges, allowing the outlines of objects to be highlighted or finer details to be seen. Polarization can be called third dimension of lighthowever, polarizing cameras often reveal physical properties that are invisible using conventional images.

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“We believe that the light control mechanism we created using a multilayer structure can also be used to develop other optical devices, including holographic devices and beam generators, or for optical imaging,” said the study’s lead author. Fan FanProfessor of Physics and Electronics at Hunan University, said in an interview statement.

Hand holding a bifocal lens.

Researchers have developed a bifocal lens based on two layers of liquid crystal (LC) structures. The intensity of the two focal lengths can be easily adjusted by applying an external voltage. (Image credit: Fan Fan, Hunan University)

The team focused on creating two-layer structures rather than the single-layer structures that most liquid crystal devices are made of. The structures were made from a liquid crystal cell as well as a liquid crystal polymer, both of which are standard materials in the development of lenses intended for holographic imaging. This allowed the researchers to vary the intensity of the two foci. The development of multifunctional holographic devices provided inspiration, but the technology could be used “beyond the field of holographic displays,” Fan said.

Some bifocal lenses can produce different focal points depending on the polarization of the incident light, but this new design allows the focus to switch on command, controlling the polarization states of the output beams. The liquid crystal layer also allows the lens to quickly switch between focus points when voltage is applied.

Scientists plan to use the new lenses in several types of multifunctional devices. However, in order for the optical components used in this technology to be more practical, they emphasized that the cost of mass production of components must be reduced. If this happens, the team will be able to develop and implement fast and accurate layer alignment technology, the researchers said in a statement.