Superlum. Broadband Sources. Superlum is a leading manufacturer of superluminiscent diodes and modules. It is an international company with headquarters located in the Republic of Ireland. We are committed to excellence in quality of products and services with personal attention to your project: big or small, commercial or academic. We develop and manufacture: Low coherent Light Sources based on SLED modules with special Driving Electronics Superluminiscent Light Emitting Diode (SLED) Modules covering the spectral range of 650 – 1620 nm Customized versions of the above products.