Manufacture of optical light guides

A method for manufacturing parts for optical light guide elements, the method comprising

• a′) providing a plate having an upper face and a lower face which are aligned parallel to each other;
• b′) obtaining a plurality of initial bars, each initial bar extending along a respective initial-bar direction from a first bar end to a second bar end, by conducting a plurality of cuts through the plate which run parallel to each other and parallel to the initial-bar directions and which create cut faces which are aligned perpendicularly to the upper and lower faces,
• wherein the initial bars have a first side face extending from the first bar end to the second bar end, the first side face being reflective;
• b) rotating each initial bar by 90° about the respective initial bar direction and positioning the initial bars in a row with their respective initial-bar directions aligned parallel to each other and with their respective first side faces facing towards a neighboring one of the initial bars;
• c) fixing the plurality of initial bars with respect to each other in the position achieved in step b) to obtain a bar arrangement;
• d) segmenting the bar arrangement into prism bars by separating the bar arrangement into sections by creating cut faces which are at an angle with respect to the initial-bar directions;
• and
• e) segmenting the prism bars into parts.