Paja

TV Remote controller use a infrared LED to send commands but anything hot glows infrared which means a infrared detect any thing hot. However, the infrared sensor for the TV remote controller only detects if the infrared flash with 38KHz.

This feature can be used in a object detection. Put both a infrared LED and infrared Sensor next each other. When the object come over the sensor, it reflect infrared light from the LED and the sensor detects the infrared light.

schematic plan

PBasic Code

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