Selected Project Prism Portal
Prism Portal. Concept art courtesy of the project team.

Clare Hart-Slattery
Public Art Artist

Ryan Sison
Architectural Designer

Tigran Tyler Pell
Support Services Manager for Tenderloin Housing Clinic



Central Market

Prism Portal is a rainbow portal composed of interlocking grids that use light and color to attract passersby; it is a tribute to San Francisco’s rich LGBT history.

Prism Portal is a geometric semi-enclosed passageway that combines an interlaced support structure with translucent colored acrylic panels that are used to represent the colors of the rainbow. The colored panels are placed intermittently throughout the structure and are oriented at different angles to capture and reflect color and light. As light passes through the colored panels, rainbow shadows are cast on to the sidewalk. As the sun moves through the sky, the projection of the rainbow shifts and skews. The bright and vibrant portal engages pedestrians by capturing their attention and offering an interactive experience.

The open air structure which stands twelve feet high is both vast and unassuming. It is a tribute to the long history of the LGBT community within San Francisco. One passes through the structure via the entryway which is nearly five feet wide and over seven feet tall, and is wheelchair accessible. Upon entering the passageway, the voices and stories of some of those who have held a place within the rich history of San Francisco’s LGBT community become audible. Printed transcripts of the stories are also available for those who are hearing impaired.

The bright physical structure that contrasts with the monochromatic tones of the street, sidewalk and buildings will attract passersby. The sound of voices will lure people in and engage them further. By pausing to hear the stories being told, people will become more aware of the larger community and history that surrounds them.

People will interact with the physical structure by passing through and around it. They will also interact with the reflection of the light upon the sidewalk as their shadow blocks the light source as they move. At night, the archway will be lit using LED strips along the support structure that mirror the colors of the rainbow creating a vibrant glowing passageway on the darkened street.

The waterproofed 2×3 studs used to form the support structure, the acrylic panels, and the LED strips are all extremely durable materials which make Prism Portal sustainable for extended outdoor exposure and interaction. The structure is appealing to all those who come upon it regardless of age, class, or race.

Project Gallery


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