Ceramic Al4O4C, which has few active functions, has been used as an additive in carbon-containing refractory materials to improve their oxidation resistance and thermal properties. Herein, the crystal and electronic structures of this novel material were systematically investigated for opto-electrical applications, which revealed interesting fluorescence features via photoluminescence (PL) and cathode luminescence (CL). When a 325 nm laser was focused on one end of a single Al4O4C needle, the entire needle was illuminated by the blue emission, which implies that this material exhibits excellent waveguide properties. Interestingly, the thin end exhibited the highest light intensity even though the excited region was located at the thick end. We believe the reason for this observed behaviour is related to the excellent waveguide behaviour as well as to the needle shape, which induces this intriguing blue-light convergence effect. Ab initio calculations demonstrated that the emission light emanates from the interband transition.