No, physical 3D letters aren’t required. You can use a 2D sign or projection instead. The key requirement is that your full licensed event name is clearly and prominently visible on stage.
Many teams create their own letters, partner with local schools or universities, or purchase them. Choose an approach that fits your budget, stage size and overall design. For more guidance, see the Design the Experience section of the TEDx Organizer Guide.
More questions? Ask TEDxAssist!