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Chapter 3 Measurement Procedures
索引
4
3
2
1
7
6
5
10
9
8
Detection of reflected light uses modulated light to minimize the
effects of incident light. When this modulated light is input for a
fixed period of time (about 0.2 ms) or longer, a single pulse is
detected. For this reason, if the light pulse generated by the
passing reflective tape is less than 0.2 ms detection is not possi-
ble.
The range that can be detected with a 12 mm square target of
reflective tape is indicated below.
3.4 Precautions in Measurement of
High-Rotation Objects
*Radius is the distance between the center of the rotating ob-
ject and the center of the tape.
Rotation (r/min.)
Reflective tape
Center
The area of the reflective tape.
60
40
20
60
10
6
5
10 (×10
4
)
1
Radius
Rotating body
Radius
(mm)
