The first of these systems is a "light curtain", named for the nature in which it operates.

An opto-electronic device used in security applications, also known as a light curtain.

By reducing the need for physical guards and barriers, light curtains can increase the maintainability of the equipment they are guarding.

The following partial list of standards should be used for guidance when implementing light curtains:

No glass showed in them, just the light curtains.

He was still chuckling when she eased around the light curtain surrounding her father's bed and sat down in the single chair.

There were no shutters on these: only light curtains which drew across.

Nevi and Zentz positioned themselves behind the light curtain, calling out strategy codes to each other.

Such information may be e.g. an alert signal triggered when someone or something has breached a light curtain on a factory floor.

It lay at the base of a window screened with light curtains.