The Pololu QTR reflectance sensors carry infrared LED and phototransistor pairs that can provide analog measurements of IR reflectance, which makes them great for close-proximity edge detection and line-following applications. The modules come as compact, single-sensor units (QTR-1A and QTR-1RC; QTR-L-1A and QTR-L-1RC), 3-sensor arrays (QTR-3A and QTR-3RC), or as 8-sensor arrays (QTR-8A and QTR-8RC) that can be optionally split into a 2-sensor array and a 6-sensor array. | The Pololu QTR reflectance sensors carry infrared LED and phototransistor pairs that can provide analog measurements of IR reflectance, which makes them great for close-proximity edge detection and line-following applications. The modules come as compact, single-sensor units (QTR-1A and QTR-1RC; QTR-L-1A and QTR-L-1RC), 3-sensor arrays (QTR-3A and QTR-3RC), or as 8-sensor arrays (QTR-8A and QTR-8RC) that can be optionally split into a 2-sensor array and a 6-sensor array. |