Research Team Uses Water Vapour Planes For Interactive Display Screens

Technology that could bring R2D2’s projection of Princess Leia in Star Wars a step closer has been developed by a University of Bristol research team. The MisTable uses a set of vapour curtains as interactive projection screens to display computer images.

The team will present their development at the prestigious ACM CHI 2014 to be held at the Metro Toronto Convention Centre between 26 April and 1 May by the Association for Computer Machinery (ACM).

Mist information

Attendees at the computer-human interface (CHI) conference will see how the table uses two fans above and below the edges of a tabletop display to create thin walls of mist which are used as screens. The medium is a mixture of glycerine and water vapour similar to the rolling mist effects used in theatrical productions. According to the developers, the vapour is dry and does not wet the hands of the users.

The screens are touch-enabled so viewers can manipulate the images in front of them or transfer displays back and forth from the screen in front of them onto one of the other three screens or down onto the LCD on the table’s flat surface.

The MisTable project has been led by Sriram Subramanian, Professor of Human-Computer Interaction, and Dr Diego Martinez Plasencia at the Bristol Interaction and Graphics (BIG) unit of Bristol University’s Department of Computer Science. Rather than trying to produce a 3D image, the team’s aim was to solve a problem inherent in tabletop displays but the floating nature of the image produces a pseudo-3D effect.

Off the wall

Subramanian explained that users of tabletop screens often use wall projections because the orientation of the screen may not suit all users around a table but these are distanced from the viewers. By creating vertical displays, the problem is solved.

“The personal screen provides direct line of sight and access to the different interaction spaces. Users can be aware of each other’s actions and can easily switch between interacting with the personal screen to the tabletop surface or the interaction section. This allows users to break in or out of shared tasks and switch between ‘individual’ and ‘group’ work,” he said.

The ethereal nature of the vapour screen places demands on image quality requiring the projection’s brightness to be altered in different places to create a consistent image. This is achieved by the use of a colourimeter to constantly measure the brightness of the red, green and blue light. The system then creates a “texture template”, a brightness map, that tells the projector how to compensate for the irregular diffusion to create a constant result.

Personal screens allow the each user’s view to be customised, as well as maintaining all of the established tabletop interface techniques, such as touch and tangible interactions.

Published by permission of TechBritannia.co.uk