3-5
1
2
3
Basic Usage
Detection Method
3-3 Detection Method
The main detection methods available are through-beam and diffuse reflective, which detect the object as
shown below.
Through-beam
Two fiber units are installed so that one emits and one receives light, and the object passes between the
units. Light is received when no object is present and is not received when an object blocks the light axis.
Detection is performed according to the received light amount.
Light is received when no object
is present.
The light axis is blocked and
light is not received when an
object is present.
Diffuse Reflective
Diffuse reflective fiber units contain both a light emitter and receiver.
They perform detection by receiving reflected light from an object.
Light is not received (or the
received light amount is low)
when no object is present.
The received light amount is high
and light is determined to be
received when an object is present.
* If the object is a dark color and the background is a bright color, light being received/not received may occur
in the opposite manner as described here.
Object
Object