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Measure Light and Optical Changes with a Compact Sensor
The QTR-1A Reflectance Sensor 2-Pack is an optical interrupter sensor with analog output designed for light logging, optical switching, line tracking, and brightness-aware projects. It is a practical fit for makers, students, and engineers who want reliable sensor data in embedded builds.
Key details include Output voltage range: 0 to supplied voltage; Operating voltage: 5.0 V; Output format: analog voltage.
Why you’ll love it
- Key feature: Use a microcontroller’s analog-to-digital converter (ADC) to measure the voltage.
- Controller output: analog voltage
- Power range: 0 to supplied voltage
- Current draw: 17 mA
- Compact size: 0.3" x 0.5" x 0.1" (without optional header pins installed)
- Useful spec: 0.125" (3 mm)
Compare with similar products
| Product | Sensor style | Standout |
|---|---|---|
| QTR-1A Reflectance Sensor 2-Pack | optical interrupter sensor with analog output | Current item |
| QTR-8A Reflectance Sensor Array | optical interrupter sensor with analog output | analog output |
| QTR-3RC Reflectance Sensor Array | optical interrupter sensor | model QTR-3RC |
| QTR-1RC Reflectance Sensor 2-Pack | optical interrupter sensor with digital output | model QTR-1RC |
What you can build
This sensor is a good fit for automatic brightness control, line followers, light meters, UV monitors, flame detection, and optical encoders.
Starter bundles
Pair it with an Arduino-compatible board, ESP32, or Raspberry Pi, plus a breadboard and jumper wires for quick setup and testing.
Recommended add-ons
Useful add-ons include breadboards, jumper wires, displays, enclosures, and logging modules, depending on how you plan to power, mount, and log the sensor.
Technical specifications
| Product | QTR-1A Reflectance Sensor 2-Pack |
|---|---|
| Output format | analog voltage |
| Output voltage range | 0 to supplied voltage |
| Operating voltage | 5.0 V |
| Supply current | 17 mA |
| Dimensions | 0.3" x 0.5" x 0.1" (without optional header pins installed) |
| Optimal sensing distance | 0.125" (3 mm) |
| Weight without header pins | 0.008 oz (0.2 g) |
| Maximum recommended sensing distance | 0.25" (6 mm) |
Wiring & usage notes
Many modules in this style expose both analog and digital pins. Use the analog pin for raw readings and the digital pin for threshold-based switching, if available.
What’s in the box
1 × QTR-1A Reflectance Sensor 2-Pack
Frequently Asked Questions
What does the QTR-1A Reflectance Sensor 2-Pack measure?
It is designed to measure light, reflection, or beam interruption.
Can I use it with Arduino, ESP32, or Raspberry Pi?
Yes. It is well suited for common maker and embedded platforms, as long as you power it at the correct voltage and match the signal level to your controller.
How do I connect this Analog and digital sensor?
This module may provide both analog and digital outputs, depending on how you wire and read it.
Does it need calibration?
Yes. Chemical and gas sensors usually need warm-up time, calibration, and periodic checking if you want stable readings.
Is it good for prototyping?
Yes. It is a practical choice for learning, proof-of-concept builds, and small automation projects.
Manila stock. Order before 16:00 PHT, ships today via J&T or LBC. Provincial: 1–3 working days.
Schools / class POs: we accept Purchase Orders for accredited schools and universities. contact us with your PO details.
Returns: 7-day inspection window for DOA units. Email proof of issue and we ship a replacement.
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