摘要 |
A waveguide in which coherent light is to propagate along its longitudinal axis has formed therein a first scattering zone (103) that runs along the longitudinal axis and that is to scatter the propagating coherent light (105) out of the waveguide at a non-zero angle relative to the longitudinal axis. Means for vibrating a light spot of the coherent light relative to the waveguide, or means for dynamically changing a focus of the light spot, is provided, so that light coupling of the coherent light into the waveguide changes over time thereby generating different speckle patterns in the waveguide that overlap with the first scattering zone. Other embodiments are also described and claimed including one where a functional or diffusing coating (102) is provided that in combination with the first scattering zone yields a reduced speckle pattern. |