| 摘要 |
<p>This invention concerns a device (5) arranged to illuminate an area. The device comprises a light source (1) arranged to transmit a light lobe coded with information, and having a predetermined solid angle defining the width of the lobe. The device (5) is characterized in that the light lobe is expandable/compressible between a first mode in which the light lobe has a first predetermined solid angle and a second mode in which the light lobe has a second predetermined solid angle and in that the light lobe is arranged to carry first information in the first mode and second information in the second mode.</p> |
