To provide a signal display light by which a light leakage between display units is eliminated by means of a simple configuration.

A circuit substrate 1 where multiple LED 11 are erected in a circumferential shape, a reflection mirror 2 having a truncated conical reflection surface which reflects an LED light in a circumferential direction and plural conductive plates 5 for wiring a part between circuit substrates between the laminated display units are combined, and their circumference is covered by a glove 3, so that the display units are constituted. The display units are laminated so as to form the signal display light and to emit a signal light. A light shielding piece 24 projected in a horizontal direction is arranged in the outer edge of the conical body of the reflection mirror 2 and held between the laminated gloves. A part between the reflection mirror 2 and the glove 3 is made to be a state where a gap to the adjacent display unit is eliminated by the light shielding piece 24. Thus not only the light leakage caused by the gap but also the light leakage caused by reflection against the glove are prevented.