Curtain
Curtain turns up in 2 fields: lighting, nonwovens. Here is what it means to the people in each one.
Curtain in lighting
A large piece of fabric used to conceal the stage, mask equipment, or control light spill.
A curtain in theatrical and studio environments serves as a visual barrier, masking off-stage areas or hiding the set before a performance. In lighting design, heavy, opaque curtains are critical for absorbing stray light and preventing unwanted reflections. They are often rigged on tracks to allow rapid deployment or removal during scene changes.
"Make sure the main curtain is completely closed before you strike the work lights."
Curtain in nonwovens
Line slang for the wide sheet of falling filaments between a spunbond spinneret and the laydown belt.
Seen from the side, the filaments leaving a spunbond beam look like a curtain, and operators watch it for gaps, flutter and broken or stuck filaments. A steady, even curtain means even laydown; a wavering one or a hole in it means quench, draw air or spinneret trouble.
"Curtain has a hole about 1.2 meters from the operator side, probably a plugged patch on the spinneret."