Abstract
Electric light at night imposes threat on human as well as ecosystems. Searching for an ecologically friendly lighting measure is a must since human beings are linked to the ecosystems. Insects play a remarkably important role on the maintenance of ecosystems, hence, we first investigated the effects of various electricity-driven lighting sources on the attraction of insects after dusk. The studied lenses included the extensively adopted light emitting diode (LED), the merging organic light emitting diode (OLED) and the traditional incandescent bulb. We found that the OLED light attracted much less insects than the LED and incandescent light. Furthermore, the light with a lower color temperature attracted lesser insects, regardless LED or OLED. At 5,000 K for example, the number of insects attracted by LED was 3.6 times that of OLED. The number of insects attracted by the 5,000 K LED was 4.3 times that of the 3,000 K LED. Surprisingly, the 2,400 K incandescent bulb attracted more insects than the OLED light either at 1,900 K, 3,000 K or 5,000 K. All these phenomena suggest that light containing shorter wavelength emission tends to attract more insects, depending on their spectra. This also explains why the blue light-less OLEDs attracted the comparably least amount of insects. We are thrilled to learn that these insect friendly OLEDs, especially the one with the lowest color temperature, are also human friendly from the perspectives of retina protection and melatonin generation.