‘Origami-Like’ Objects Can Instantly Change Their Transparency

A team of European researchers have created a new, "origami-like" approach to designing and manipulating the transparency of real-world objects which far surpasses previous techniques in ease of implementation and use.

As the researchers detail in a paper to be presented at the ACM User Interface Software and Technology Symposium in October, their new technique opens the door for a variety of functional and fun applications, such as lamps that appear to change shape and phone screen overlays with dynamic transparency.

To make this happen, the team leveraged the unique properties of a material called a polymer-dispersed liquid crystal (PDLC) switchable diffuser, which changes from opaque to transparent when low levels of voltage are applied to its surface. The PDLC diffuser is a thin sheet comprised of a layer of liquid crystals sandwiched between two layers of a conductive material called indium tin oxide, all of which is encased in an outer insulating material.

The next step was designing the actual objects, which required the researchers to create a custom software which renders 3D objects as 2D cutouts. These cutouts are then laser-etched into a single sheet of the PDLC diffuser and can then be folded into their intended 3D shape. In this respect, the researchers write, their process is "origami-like" since it only uses a single sheet of paper and doesn't allow for any additional cuts besides the initial laser cut.

To demonstrate their technique the researchers made four objects: a stylized bug that is made to look like it's walking, a series of nested cubes, a 3D loading bar, and a cube with a star in it. All of the objects were made using a single sheet of PDLC diffuser and when 60 volts were applied to them the researchers were able to manipulate the opacity of the objects to achieve the desired effect.

Although the researchers are not the first to work with transparency-changing materials, their work drastically improves on existing research by allowing for faster transitions (the objects could change from opaque to transparent in about 8 milliseconds and back to opaque in 80 milliseconds), the manipulation of individual sections of the object (achieved by engraving a route for the current to travel directly into the PDLC, obviating the need for external wiring), and new types of objects (such as the nested cubes).

Although most of the objects designed by the researchers seem good for little more than the awe-factor, the team expects this approach to transparency control to have a variety of functional applications. For instance, transparency-controlled devices have already been used to create transparent desktop monitors and see-through desks that allow for the manipulation of 3D objects 'inside' the devices. They hope their method will improve upon these existing technologies and allow for previously impossible design concepts.