If your watch has Lumibrite

Lumibrite is a luminous paint that absorbs light energy of the sunlight and lighting apparatus in a short time and stores it to emit light in the dark. For example, if exposed to a light of more than 500 lux for approximately 10 minutes, Lumibrite can emit light for 3 to 5 hours. Please note, however, Lumibrite emits the light it stores, the luminance level of the light decreases gradually over time. The duration of the emitted light may also differ slightly depending on such factors as the brightness of the place where the watch is exposed to light and the distance from the light source to the watch.

In general, when you enter a dark place from a bright environment, your eye cannot adapt to the change in light levels quickly. At first, you can hardly see anything, but as time passes, your vision gradually improves. (Dark adaptation of the human eye)

Lumibrite is a luminous paint that is completely harmless to human beings and the natural environment; containing no noxious materials such as radioactive substance.

Reference data on the luminance




Fine weather

100,000 lux

Cloudy weather

10,000 lux

Indoor (Window-side during daytime)

Fine weather

more than 3,000 lux

Cloudy weather

1,000 to 3,000 lux

Rainy weather

less than 1,000 lux

Lighting apparatus (40-watt daylight fluorescent light)

Distance to the watch: 1 m

1,000 lux

Distance to the watch: 3 m

500 lux (average room luminance)

Distance to the watch: 4 m

250 lux