| 摘要 |
A luminous display device in the form of a panel for displaying a variable message includes n juxtaposed display subassemblies for display by means of bundles of optical fibres. Each subassembly includes at least one light source. The device further includes a main control circuit for generating a light intensity reference. A number of secondary control circuits are provided with each being associated with a respective one of the end display subassemblies. Each secondary control circuit includes means for receiving the intensity reference and means for monitoring the light sources of the associated subassembly so that each emitted light intensity corresponds to the reference light intensity. Monitor means are presented by each secondary control circuit and include means for directly detecting each light intensity emitted by the associated light sources, means for comparing each light intensity with the intensity reference and means for controlling the power supply to the associated light sources as a function of the result of the comparison. Means for directly detecting each light intensity comprise one or more fibres of the bundle of optical fibres and is connected to a photoelectrical converter device.
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