QTR reflectance sensors just got more affordable

I am happy to announce another price drop. This time, it’s for several of our QTR reflectance sensors!

QTR-8A and QTR-8RC reflectance sensor arrays are now $9.95 (down from $14.95) with quantity price breaks starting at just five units. These modules feature eight IR LED/phototransistor pairs spaced 0.375″ apart, and an integrated MOSFET allows the LEDs to be turned off for additional sensing or power-savings options. These boards can optionally be broken apart into a six-sensor array and a two-sensor array.

QTR-1A and QTR-1RC sensors are now available in packs of two for $4.25 (and for even bigger savings, we’ve dropped the individually packaged QTR-1s from $2.49 to a clearance price of $1.95).

More about QTR sensors

These sensors and the rest of the modules in the QTR family combine infrared LED emitters with phototransistors that detect the amount of reflected IR. This makes them great for applications like edge detection and line following. Each type of QTR sensor is available in two versions: “A” units indicate the reflectance with an analog voltage, and “RC” units have digital I/O-compatible outputs that let you measure the reflectance by timing the discharge of a capacitor.

And don’t forget the newer members of our QTR family, which were priced from the outset in line with our efforts to offer better quality products at lower prices:

QTR-3A and QTR-3RC reflectance sensor arrays make a great minimal sensing solution for a line-following robot. They use smaller sensing elements than the QTR-1 and QTR-8 versions, so they can fit three IR LED/phototransistor pairs onto a compact 1.25″ × 0.3″ board.

QTR-L-1A and QTR-L-1RC sensors use a discrete right-angle infrared LED and a right-angle phototransistor, each mounted on a different side of the board. This results in a very small sensor that has a low profile along the plane of detection.

The Zumo reflectance sensor array incorporates six IR LED/phototransistor pairs onto a 2.6″ × 0.6″ board, with the distance between the sensors increasing as they get farther from the center of the array. This module was designed to work directly with the Zumo shield on our Zumo robot, but it can also be used as a general-purpose QTR sensor array.

QTR sensor size comparison. Top row: QTRX-HD-07, QTR-HD-07; middle row: QTR-3, QTR-1, QTR-L-1; bottom row: QTR-8.