[D66] Zwart Licht

[R.O.]

rene at NUC:~$ describe "black light"
en:
light fixture that emits long-wave ultraviolet light and very little 
visible light

A **blacklight** (or often **black light** ), also referred to as a 
**UV-A light** , **Wood's lamp** , or **ultraviolet light** , is a lamp 
that emits long-wave (UV-A) ultraviolet light and very little visible light.

[...]

https://en.wikipedia.org/wiki/Blacklight