Light directing expandable envelope

摘要

Disclosed is an expandable envelope that comprises a light directing film this both transmits and reflects light. In its inflated form and along with a light source, the envelope forms a light balloon that due to the light directing film provides directed light to an area surrounding the balloon.

主权项

1. An expandable envelope comprising a film that forms an external surface of the envelope, wherein at least a portion of the film is a structured light directing film having an outer structured surface defining the external surface and an inner smooth surface opposite the outer structured surface, and further wherein the expandable envelope is configured such that light at an interior of the expandable envelope is uniformly emitted from the expandable envelope on-axis to the inner smooth surface over a surface area of the structured light directing film; wherein at least a portion of the film is a reflective film; wherein a reflective portion of the reflective film is at an internal surface of the envelope; wherein the light directing film is located opposite to the reflective film such that upon inflation of the envelope, the light directing film is separated from the reflective film, and further wherein the reflective film is curved upon inflation of the envelope, and further wherein an entirety of the light directing film is inelastic and is in a single flat plane upon inflation of the envelope and all light emitted from the envelope is uniformly transmitted over the surface of the light directing film in a uniform direction.