A light emitting diode module comprising: an light emitting diode assembly comprising a plurality of light emitting diodes (112, 114, 116), the light emitting diode assembly having a first output window from which light emitted by the said plurality of light emitting diodes is output; a light directing element comprising a first input window and a second output window, wherein the light directing element is adapted to receive light at the first input window and direct the received light to be output at the second output window, wherein: the light directing element is positioned to receive light output from the first output window at the first input window; the second output window has a smaller area than the first output window; and the second output window is in a plane substantially normal to a plane of the first output window; and an additional light emitting diode assembly comprising a plurality of additional light emitting diodes, the additional light emitting diode assembly having a third output window from which light emitted by the said plurality of additional light emitting diodes is output; characterized by an additional light directing element comprising a second input window and a fourth output window, wherein the light directing element is adapted to receive light at the second input window and direct the received light to be output at the fourth output window, wherein the additional light directing element is positioned to receive light output from the third output window at the second input window; the fourth output window has a smaller area than the third output window; and the fourth output window is in a plane substantially normal to a plane of the third output window; wherein the light directing element and the additional light directing element are being positioned back-to-back; and the light emitting diode assembly and the additional light emitting diode assembly are both mounted on a single substrate comprising a flexible portion. an light emitting diode assembly comprising a plurality of light emitting diodes (112, 114, 116), the light emitting diode assembly having a first output window from which light emitted by the said plurality of light emitting diodes is output; a light directing element comprising a first input window and a second output window, wherein the light directing element is adapted to receive light at the first input window and direct the received light to be output at the second output window, wherein: the light directing element is positioned to receive light output from the first output window at the first input window; the second output window has a smaller area than the first output window; and the second output window is in a plane substantially normal to a plane of the first output window; and an additional light emitting diode assembly comprising a plurality of additional light emitting diodes, the additional light emitting diode assembly having a third output window from which light emitted by the said plurality of additional light emitting diodes is output; the light directing element is positioned to receive light output from the first output window at the first input window; the second output window has a smaller area than the first output window; and the second output window is in a plane substantially normal to a plane of the first output window; and an additional light emitting diode assembly comprising a plurality of additional light emitting diodes, the additional light emitting diode assembly having a third output window from which light emitted by the said plurality of additional light emitting diodes is output; characterized by an additional light directing element comprising a second input window and a fourth output window, wherein the light directing element is adapted to receive light at the second input window and direct the received light to be output at the fourth output window, wherein the additional light directing element is positioned to receive light output from the third output window at the second input window; the fourth output window has a smaller area than the third output window; and the fourth output window is in a plane substantially normal to a plane of the third output window; wherein the light directing element and the additional light directing element are being positioned back-to-back; and the light emitting diode assembly and the additional light emitting diode assembly are both mounted on a single substrate comprising a flexible portion.