In the context of light-based oral examination, a light engine (1) involving only minimal light losses is provided. The light engine (1) includes a light supply unit (2) for supplying light to be conveyed to a subject's oral cavity, which light supply unit (2) comprises a light source (10) configured to generate light, a luminescent converter (20) configured and arranged to receive light from the light source (10), to emit light to be conveyed to a subject's oral cavity in response to receiving the light from the light source (10), and a light guide (30) configured and arranged to receive light from the luminescent converter (20) and to convey the light to a subject's oral cavity. In a preferred embodiment of the light engine (1), semiconductor quantum dots are associated with at least one surface area of the luminescent converter (1).