We report on light and heat distributions in the active area of infrared lasers and light-emitting diodes operating at 300 K in the 0, 8–4,7 μm spectral range. To separate light and heat produced by these devices, we developed a high-resolution multi-spectral infrared (<1 m, 3–5 m and 8–12 m ranges) “vision” facility capable of providing <20 m spatial resolution and 10 s temporal resolution. We show how current crowding and Joule heating combined drastically decrease integral power emitted by light-emitting diodes and provoke remarkable non-uniformity in light and heat maps. As concerning stripe lasers, we comment on heat spreading and heat bottlenecks inside the laser dome and quality of heat sink.