He and his colleagues merged them together in a single beam, before using a flash of light to trigger a chemical reaction.

Single beam spectrophotometers use only one beam of light for measurements.

The principle was simple: while a single beam did little damage to normal tissue, where they crossed the cumulative dose was lethal.

You should never aim a single beam into the audience.

In addition to the single beam echo sounder, there are echo sounders that are capable of receiving many return pings.