An optical wireless communication device

An optical wireless communication device comprising:

• an optical system and a modem for communicating with a remote optical wireless communication device,
• the optical system comprising:
• a light generating system configured to generate and output a line beam, the line beam being a beam that, if incident upon a hypothetical planar surface at a working distance from the light generating system, would illuminate a region of the hypothetical planar surface;
• a light rotating system configured to controllably set an angle at which the line beam is output from the optical system;
• and
• a beam control system configured to, during a first mode of operation of the optical system, control the operation of the light rotating system to
• incrementally adjust the angle that the line beam is output from the optical system;
• wherein the optical wireless communication device further comprises:
• a light receiving system configured to receive reflections of the line beam or responses to the line beam from the remote optical wireless communication device;
• the modem is for communicating with a remote optical wireless communication device using the optical system;
• the region of the hypothetical planar surface having a length at least five times larger than its width;
• and
• wherein the light receiving system is configured to
• during the first mode of operation of the optical system, monitor the intensity of any received reflections of the line beam;
• at the end of the first mode of operation of the optical system, identify the angle for which the intensity of any received reflections was the largest during the first mode of operation and
• wherein the optical wireless communication device is configured to:
• use the identified angle to configure the optical system for optical wireless communication with the remote optical wireless communication device.