Patent ID: 8218235

Claim:
A projection display surface for receiving light from a projector having at least one narrow band light source having an incident visible wavelength band, wherein the incident visible wavelength band has an incident peak wavelength and an incident bandwidth, comprising: a) a substrate having a reflective layer that reflects incident light over at least the incident visible wavelength band; and b) a fluorescent agent distributed over the reflective layer, wherein the fluorescent agent absorbs a fraction of the light in the incident visible wavelength band and emits light in an emissive visible wavelength band having an emissive peak wavelength and an emissive bandwidth, wherein the fraction of the light in the incident visible wavelength band that is absorbed by the fluorescent agent is between 2% and 40%, and wherein a remaining fraction of the light in the incident visible wavelength band is reflected by the substrate; wherein return light from the projection display surface produced when incident light in the incident visible wavelength band is incident on the projection display surface contains both reflected light in the incident visible wavelength band that was not absorbed by the fluorescent agent and was reflected from the substrate and light in the emissive visible wavelength band that was emitted by the fluorescent agent, the reflected light in the incident visible wavelength band being more than 60% of the incident light in the incident visible band.