Abstract: Disclosed embodiments include a replicator arranged to receive spatially modulated light and replicate the spatially modulated light to form a plurality of replicas of the spatially modulated light by waveguiding between a reflective surface and a transmissive-reflective surface. The transmissive-reflective surface forms an output surface for the plurality of replicas of the spatially modulated light. Some embodiments additionally include a light control device (i) located in an optical path of the plurality of replicas of the spatially modulated light downstream from the output surface of the replicator, and (ii) arranged to provide a first angular turn to the replicas of the spatially modulated light. The first angular turn is caused by refractive power and has a primary component on a plane. Some embodiments also include a diffractive optical element arranged to provide a second angular turn to the spatially modulated light or the replicas thereof.

Abstract: A head-up display for a vehicle includes a picture generating unit arranged to project an image onto a screen and a replicator arranged to receive the image and replicate the image. The head-up display also includes a corrective device located in the optical path of the replicated image downstream from the replicator, arranged to compensate for a complex curvature of an optical combiner downstream from the corrective device and to form a virtual image of the image that is visible from a plurality of viewing positions of a viewing window. The corrective device is arranged to introduce a first disparity offset to at least some of the plurality of virtual image points. The first disparity offset of each virtual image point is substantially constant for the plurality of viewing positions of the viewing window and is a function of the position of the virtual image point in the virtual image.

Abstract: A diffuser arranged to rotate around a rotation centre thereof is provided. Each point on the diffuser forms a diffusion profile that is a function of radial distance from the rotation centre but rotationally invariant.

Abstract: A remote imaging apparatus such as a borescope or endoscope. The apparatus has an image relay means (4) for relaying an image along the main axis (3) from the distal end of the scope and an annular light pipe (1) for transmitting light to the distal end of the scope to illuminate the object to be viewed. At least the inner or outer surface of annular light pipe (1) is surrounded by air.