Computing Surfacesa platform for scalable interactive displays

Alban Rrustemi

Microsoft ResearchCambridge

30-June-2009

Overview

Information displays Emerging display technologies Display resolution Technology limitations Computing surfaces

A distributed architecture Implications

Conclusions

Information displays

Visual broadcasting of information

Information displays

LCD – ubiquitous

Information displays

LCD – ubiquitous Sensing

New applications

Emerging display technologies

OLED (Organic LED) Higher refresh rate (due to faster response times) Higher contrast (e.g. 1,000,000:1) Improved colour reproduction Really thin – (e.g. Sony XEL-1 is just 3mm thick) Much wider viewing angle (almost 180 degrees) Lower power consumption Can be made flexible and/or transparent Some OLED technologies are soluble

Emerging display technologies

Reflective (e-ink) E-readers Other devices

Emerging display technologies

Flexible displays More research in supporting technologies

TFT backplanes Encapsulation materials

Superior manufacturing efficiency

Motivation – large interactive displays

A new spectrum of opportunities

Thin, flexible, interactive display surfaces Scalable?

Display resolution

Pixel density TVs ~60PPI Monitor screens ~100PPI Smartphones, currently up to 300PPI

Assuming 100PPI => 4k×4k / m2 Current max monitor resolution: 3840 X 2400

WQUXGA

Resolution standards Are becoming absurd

Technology limitations

Current solutions provide limited scalability Limitations apply to all existing display systems

A problem of communication management!

Framebuffer

Renderingengine

Row/column drivers

Pixels controlled by row/column drivers

Information source Display device

CommslinkDisplay

information

Decode & controlcircuitry

Tiling

Pixels/sensors

Computing surfaces

A distributed architecture Tile structure

Pixels/sensors

CPU I/O

Memory

Network interface

Tile interconnect

GPIO

System bus

Framebuffer

Renderingengine

Row/column drivers

Pixels controlled by row/column drivers

Information source Display device

CommslinkDisplay

information

Decode & controlcircuitry

3x3 network Tile components

Display: 17” LCD Altera DE2 FPGA Nios II processor Radix-5

packet switched virtual channel network router

Computing surfaces – a prototype

Computing surfaces

A versatile architecture Implications:

Distributed output Distributed input Need for time

synchronisation

Source/sink nodes

Application regions

Information providers

Distributed output

Direct manipulation with display content is needed

2D transformations A centralised approach

becomes infeasible Alternative: distributed 2D

transformations

Distributing input

Gesture recognition A distributed architecture brings new

issues to be resolved Unistrokes:

Time synchronisation

Needed for: coordination processes distributed video playback interactive games

A distributed algorithm

Source/sink nodes

Application regions

Information providers

Conclusions and summary

Emerging display technologies will enable FP displays ubiquity Resolution scalability problems will escalate Distributed architectures become necessary

Computing surfaces Distributed 2D transformation of images Distributed gesture recognition Time synchronisation

Questions?