Assertion: optical keyboard | /r/CapableOf | allow only one beam per row of keys
Facets:
Source sentences:
text: Some optical keyboards use a special key structure that blocks the light in a certain pattern, allowing only one beam per row of keys (most commonly horizontal beam).
text: Some optical keyboards use a special key structure that blocks the light in a certain pattern, allowing only one beam per row of keys (most commonly a horizontal beam).