Manufacturing a lightguide with cut lateral edges

A method of manufacturing a film assembly comprising:

• forming a film-based lightguide comprising a lightguide region and having opposing faces with a thickness in a thickness direction between the opposing faces less than 0.5 millimeters;
• adding a layer comprising linear light turning features to the film-based lightguide while the film-based lightguide is moving in a web direction of the film such that the linear light turning features are oriented in the web direction of the film-based lightguide;
• and
• cutting the film-based lightguide while the film-based lightguide is moving in a web direction in a plurality of linear sections, the plurality of linear sections comprises linear sections that define lateral edges of coupling lightguides extending from the lightguide region of the film-based lightguide,
• wherein the linear sections are cut at first cut angle between 3 degrees and 25 degrees to a transverse direction of the film-based lightguide orthogonal to the web direction and the thickness direction.

A film assembly comprising:

• a film-based lightguide comprising a lightguide region and having opposing faces with a thickness in a thickness direction between the opposing faces less than 0.5 millimeters;
• a layer comprising linear light turning features oriented in a web direction of the film-based lightguide;
• and
• a plurality of cut linear sections comprising cut linear sections that define lateral edges of coupling lightguides extending from the lightguide region of the film-based lightguide,
• wherein the plurality of cut linear sections are cut at first cut angle between 3 degrees and 25 degrees to a transverse direction orthogonal to the web direction and the thickness direction.