Abstract: A package (10) for receiving an optical chip (20) having a light source (31) to emit light and a circuit element (33) whose performance is adversely affected by the incidence thereon of stray light from the light source. The package includes a barrier element (81) which is adapted to absorb light emitted by the light source and which is so dimensioned and arranged as to be positioned between the light source and the circuit element when the optical chip is received in the package. The barrier element may be on a shield (50) forming a part of the package.

Abstract: The application describes the addition of serrations to the edge of the light transmissive layer of an integrated optical device. This enables scattered background light to be coupled out of the device, improving the signal-to-noise ratio.

Abstract: The integrated light absorber comprises a light chamber integrated in an optical chip, the chamber having upper and lower walls lying substantially parallel to the chip and peripheral walls extending there between and a light input port in a peripheral wall for receiving light to be absorbed, e.g. from a rib waveguide. At least one of the walls have light absorbing properties and the chamber is shaped so that the majority of light which enters the chamber through the light input port undergoes multiple reflections and so is absorbed by the walls of the chamber. Circular and star-shaped chambers are described.