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Lesson 14 Photo-interrupter
Introduction
A photo-interrupter is a sensor that arranges light-emitting component and light-receiving
component face-to-face and packages them together.
It applies the principle that light is
interrupted when an object passes through the sensor. Therefore, photo-interrupters are
widely used in speed measurement.
Components
-
1 * SunFounder Uno board
- 1 * USB data cable
- 1 * Photo-interrupter module
- Several jumper wires
Experimental Principle
Basically a photo-interrupter consists of two parts: transmitter and receiver. The transmitter
(e.g., an LED or a laser) emits light and then the light goes to the receiver. If that light beam
between the transmitter and receiver is interrupted by an obstacle, the receiver will detect
no incoming light even for a moment and the output level will change. In this experiment,
we will turn an LED on or off by using this change.
Experimental Procedures
Step 1:
Build the circuit
Photo-interrupter Module SunFounder Uno
S --------------------------------------- A0
- -------------------------------------- GND
+ --------------------------------------- 5V
Step 2:
Program (Please refer to the example code in
LEARN -> Get Tutorial
on our
website
)
Step 3:
Compile
Step 4:
Upload the sketch to SunFounder Uno
SunFounder