3m Innovative Properties Company

Robert Bennett

John Allen Wheatley

Gilles J Benoit

David Scott Thompson

Keith Michael Kotchick

Paul Edward Humpal

Karl J L Geisler

Stefan O Dietrich

Kay-Uwe Schenke

Guido Hitschmarin

Lighting systems and devices include a light-transmissive tube and a light source assembly. The light-transmissive tube defines a cavity that extends along a longitudinal axis, at least a portion of the tube having an inner structured surface facing the cavity, and an outer structured surface facing away from the cavity. The light source assembly is disposed to inject light into the cavity, and includes one or more discrete light sources such as LED sources. The inner and outer structured surfaces of the tube are configured to direct a first portion of the injected light out of the tube through the outer structured surface and to direct a second portion of the injected light back into the cavity, such that a virtual filament, or pattern of virtual filaments, appears in the tube.

Solid state lighting device with virtual filament(s)

Lighting systems include a light-transmissive tube and a light source assembly disposed to inject light into a cavity defined by the tube. The cavity extends along a longitudinal axis. At least a portion of the tube includes an inner structured surface facing the cavity, and an outer structured surface facing away from the cavity. The inner structured surface is configured to direct a first portion of the injected light towards the outer structured surface, and a second portion of the injected light back into the cavity. The inner structured surface includes elongated first features and the outer structured surface includes elongated second features. At least one of the elongated first features and the elongated second features are oriented obliquely relative to the longitudinal axis such that they form respective helixes along the tube.

Tubular lighting systems with inner and outer structured surfaces

An optical element having a front side and a back side operates in an ambient lit mode and a backlit mode. The optical element includes a diffusely reflecting layer facing the front side for reflecting ambient light. A light absorbing layer faces the back side and is positioned to prevent back light from illuminating the diffusely reflecting layer. A plurality of light transmitting regions extend through the light absorbing layer and the diffusely reflecting layer for permitting back light to pass through in a restricted angular range without illuminating the diffusely reflecting layer.

Day and night film

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Berkshire, United Kingdom

Robert Bennett