- Questions & Answers
Looking for edge or line sensor? You are at the right place. This QTR-1A reflectance sensor carries a single infrared LED and phototransistor pair in a tiny 0.5" x 0.3" module that can be mounted almost anywhere. The reflectance measurement is output as an analog voltage. This sensor is sold in packs of two units.
Note: The QTR-1A reflectance sensor requires an analog input to take readings. So you need controller that have analog input, example Arduino UNO.
This QTR-1A reflectance sensor carries a single infrared LED and phototransistor pair. The phototransistor is connected to a pull-up resistor to form a voltage divider that produces an analog voltage output between 0 V and VIN (which is typically 5 V) as a function of the reflected IR. Lower output voltage is an indication of greater reflection.
The LED current-limiting resistor is set to deliver approximately 17 mA to the LED when VIN is 5 V. The current requirement can be met by some microcontroller I/O lines, allowing the sensor to be powered up and down through an I/O line to conserve power.
This sensor was designed to be used with the board parallel to the surface being sensed. Because of its small size, multiple units can easily be arranged to fit various applications such as line sensing and proximity/edge detection.
- Dimensions: 0.3" x 0.5" x 0.1" (without optional header pins installed)
- Operating voltage: 5.0 V
- Supply current: 17 mA
- Output format: analog voltage
- Output voltage range: 0 to supplied voltage
- Optimal sensing distance: 0.125" (3 mm)
- Maximum recommended sensing distance: 0.25" (6 mm)
- Weight without header pins: 0.008 oz (0.2 g)