Gambling on fiber optics

Lighting Images of Perth, Western Australia, was not prepared to gamble that its client, the Burswood Island Resort Casino, would invest AU$700,000 (US$500,000) in an installation of 15 miles (24km) of optical fiber based entirely on sketches and the design team's assurances of how it would look, so the lighting company set about showing the design as computer-generated renderings.

The fiber was to be a core element of a facelift to the Gaming Room and entrance foyers of the casino, which had not been updated since opening its doors in 1985. Casino management had opted for what was essentially a lighting-only upgrade to achieve a more modern, glitzy look for the room within the constraints of minimal disruption to operations and maximum impact for the expenditure.

The Gaming Room entrance and foyer, which previously had exhibited the charm and character of a late-70s shopping mall, would feature columns with color-changing capitals, a fiber-optic star-domed ceiling, and a color-changing Burswood Island Resort (BIR) logo set into the new granite floor. In the Gaming Room, new translucent-domed luminaires featuring constantly changing kaleidoscopic patterns would replace the original chandeliers, which would have been more at home in the grand ballroom of a Russian cruise ship, and thousands of meters of linear optical fiber was to replace the budlights outlining the barrel-vaulted ceiling.

Martin Klaasen was Lighting Images' lead designer on the project, which not only had to meet the BIR management's requirements for aesthetics and functionality, but also had to obey the Chinese design principles of feng shui, in deference to the high level of Chinese patronage enjoyed by the casino. "We made certain that the patterns and light flows in the designs matched with the energy flows determined by the feng shui consultant," says Klaasen. "The shapes and orientations of some of the elements of our design also required a few last-minute adjustments to conform to feng shui principles."

The fiber-optic star ceiling in the casino's foyer was constructed using an astronomical map from the Perth Observatory that detailed the locations of the 690 major stars visible from Perth, along with a further 1,100 star points which were used to represent the milky way. The star map was reproduced on the dome by projecting a correctly oriented transparency of the map onto the ceiling dome in order to place each of the fibers accurately enough so that it could be possible to cross the foyer of the casino entirely by astronomical navigation.

The new house lights feature a shallow translucent dish, 2.4m (8') in diameter, onto which an SGM Color Dynamic 100 projector has been focused from above. The Color Dynamic uses a color wheel and a device consisting primarily of a bundle of optical fibers to produce a series of ever-changing color patterns that bear some resemblance to Mandlebrot fractals. Legend has it that the fiber-optic module was originally developed to produce calming patterns as an aid to Soviet cosmonauts attempting to reacclimatize to earthbound conditions after prolonged stays in the Mir space station.

The task of producing the renderings fell to Simon Crone, a partner in Lighting Images, and Lightmaster, the visualization tool he has developed based on the Eagle 3D modeler and the Radiance radiosity rendering engine. Crone, who has spent much of the last decade developing lighting models for architectural rendering and visualization has been working with the Radiance renderer (developed at Berkeley's Lawrence Livermore Labs by Greg Larsen-Ward) since researching for his architectural dissertation on the ability to render lighting conditions.

"I selected Radiance after examining a number of rendering packages," explains Crone. "It was very powerful but extremely difficult to use, so my dissertation related to designing and building an interface between Radiance and the Eagle modeling software in use at Curtin University of Technology. I then went on and did a master's degree where I took that further and developed a localized daylighting model which took account of special characteristics of Perth's daylight, such as its bright horizons. What I wound up with was a CAD package with all the bells and whistles and buttons to actually drive the Radiance rendering engine in addition to constructing the model."

Eagle is essentially a 3D modeling program with some basic drafting facilities, as distinct from the widely used AutoCAD, which is more oriented to drafting. Eagle does, however, have the capacity to import both drawing exchange files (.dxf) and standard AutoCAD drawing (.dwg) files.

In the case of the Gaming Room at Burswood, there was a partial 3D CAD model of the project in ArchiCad format which Crone imported into Eagle before modeling fully and rendering. Crone explains, "To avoid having to wait five years for the model to render we needed the geometry of the model to be as clean as possible. Unfortunately CAD packages such as ArchiCad and AutoCAD export some elements of their geometry as a series of patches rather than as a description of a surface. For example, the foyer dome in the model was defined as something like 10,000 separate polygons which I was able to rip out and replace with a simplified vector definition of a domed surface."

Crone then used the extensive materials library in his Lightmaster interface to assign materials to each surface of the Eagle model before it translated the completed models into Radiance format and exported them to Radiance for rendering. He emphasizes the importance of avoiding unnecessary complexity in the models, as the radiosity rendering model on which Radiance is based involves the calculation of the light reflected from every surface to every other surface in the model.

One of the more interesting challenges in the project for the Lighting Images team was to accurately render the 2.9km (1.8mi.) of Hilight 50 linear (side-emitting) optical fiber incorporated in Klaasen's design. "There was no IES file available to provide us with the photometric data for this type of fiber," recalls Crone. "But we received a lot of help from Kevin Monahan at Digilin in Brisbane (Queensland), who supplied the fiber and designed and manufactured the lightboxes. Rather than being forced to assume that the fiber was a light-emitting cylinder, we were able to get real figures for light output per unit length. We also used the RGB translation of the CIE color coordinates for the dichroic filters in the wheels of the Arcblaze lightboxes to keep the color of the rendered fiber as accurate as possible."

To provide the subtlety of color control required by Klaasen's design, Digilin developed a custom version of its DMX-controlled Arcblaze 150 fiber-optic lightboxes that feature two color wheels on a common axis to provide subtractive color mixing. The micro-stepper motors on the wheels give 2,500 steps per revolution, which enables the drive electronics to produce extremely smooth transitions between the 256 positional steps that can be specified with a single DMX channel for each wheel. In these lightboxes one of the color wheels contains seven colors and a clear (no color) segment while the other has six colors, a clear segment, and an opaque segment to enable blackouts.

Burswood Island Resort management was so impressed with the quality of the renderings produced by Lightmaster that they were prominently displayed in the staff canteen and featured in Winning Ways, the casino's house magazine, to familiarize all staff with the outcome of the refurbishment taking place all around them.

In an unusual turnaround from the familiar circumstance of lighting being seen as very much the handmaiden to the other elements of design and architecture, the Burswood marketing and promotions departments were so impressed by the new looks that they had seen on the rendered images that they actually ran an advertising campaign on the theme of "Burswood Casino has spectacular new lights," featuring the new lighting around the traditional Australian game of Two-Up (known elsewhere as Swy), and held a special night to celebrate the official switch-on. The payoff for Martin Klaasen, Simon Crone, and the Lighting Images team, however, came when Jack Oswald, Burswood Island Resort's chief engineer, turned to Klaasen and said, "It's exactly how you said it would be."

Andy Ciddor of The Kilowatt Company has been a practitioner, educator, and writer in the field of production technology for 30 years. He can be reached at [email protected].