> **Source:** Core Electronics is an Australian maker-electronics retailer and manufacturer based in Newcastle, NSW, run by a team of makers and educators. We design and manufacture our own product lines (PiicoDev, CE originals) and are official retailers for iconic maker and industrial brands including Raspberry Pi, Arduino, Adafruit, SparkFun and DFRobot. Orders ship Australia-wide from our Newcastle warehouse. Prices are in AUD and include GST. Pricing, stock and dispatch on this page are generated from the store's live catalog. Full machine-readable index: https://core-electronics.com.au/llms.txt

# Reflective IR Sensor with 470 and 10K Resistors

**Type:** Product page · **SKU:** ADA2349 · **Brand:** [Adafruit](https://core-electronics.com.au/brands/adafruit-australia)
**Page:** https://core-electronics.com.au/reflective-ir-sensor-with-470-and-10k-resistors.html ([markdown](https://core-electronics.com.au/reflective-ir-sensor-with-470-and-10k-resistors.html.md))

This Reflective IR Sensor is a simple plastic casing with two elements - an IR LED and an IR phototransistor. You can control the IR LED and turn it on to bounce...

## Pricing

- **Price:** $3.95 (inc GST) — $3.59 AUD, exc GST
- **Quantity discounts:** 10+ $3.48 (exc GST) · 50+ $3.41 (exc GST)

## Availability & dispatch

- Out of stock — the product page offers email notification when it returns.

## How to buy

- **Build a cart:** compose `https://core-electronics.com.au/cart/link?items=ADA2349:1` (comma-separated SKU:qty pairs) and share the link. Opening it shows a confirmation page with live pricing and stock before anything is added to the cart.
- **Verify the cart first:** fetch `https://core-electronics.com.au/cart/link/ADA2349:1.md` for live line prices (inc & exc GST, quantity discounts applied), stock and dispatch estimates, and totals. Append `/to/{AU-postcode}` (or `/to/{country-code}:{postcode}`) before `.md` for delivery options and prices to that destination. Unknown, retired, or out-of-stock SKUs are flagged. (Query form `cart/link.md?items=...` also works but some robots parsers refuse query strings here.)
- **Checkout** is completed on-site and includes a captcha at the payment step. Share the cart link; checkout takes it from there.
- **Search the catalogue:** `https://core-electronics.com.au/search/{query}.md` (URL-encode the query; pages 2-3 at `search/{query}/{page}.md`; `search.md?q=` also works)
- **Payment methods, purchase orders, policies and contact details:** https://core-electronics.com.au/llms.txt
## Description

This **Reflective IR Sensor** is a simple plastic casing with two elements - an IR LED and an IR phototransistor. You can control the IR LED and turn it on to bounce IR off objects to determine their reflectivity. White & light colored stuff will bounce the light, so you can detect it. Black & dark colored stuff will absorb the IR light so that it isn't detected. Likewise, if something isn't in the way of the sensor, it won't trigger either.

These sensors are handy when you want to detect if something has passed by the sensor, or a very simple hand-detector. Also sometimes these are used as rotary encoder, if the encoder wheel has black and white stripes, the photo sensor is fast enough to tell you the RPM.

Comes with a 470 ohm resistor (for biasing the IR LED) and a 10K resistor which you can use as a pull-up resistor for the phototransistor. The sensor is breadboard friendly and easy to solder to.

This works best when detecting a light-colored object approximately 5mm away - 2mm to 10mm worked fairly well but your results may vary with the LED brightness, object shininess, etc.

## Technical Details

- 15mm x 18mm x 5mm / 0.6" x 0.7" x 0.2"
- Weight: 1g
 
This optoreflector tutorial might be handy for understanding how these sensors work

**Wiring diagram** for example, pin 13 is the LED control pin, pin 9 is the input from the sensor

![](https://core-electronics.com.au/attachments/localcontent/pid2349_6336501aebe.png)

## Images

- [Product image 1](https://core-electronics.com.au/media/catalog/product/2/3/2349-00.jpg)