This small lidar-based distance sensor detects the presence of objects within 5 cm (2″). It has a single digital output that drives low when an object is being detected; otherwise, it is high. It works over an input voltage range of 3.0 V to 5.5 V, and the 0.1″ pin spacing makes it easy to use with standard solderless breadboards and 0.1″ perfboards. Overview This compact sensor is a great way to quickly detect the presence of nearby objects. As long as the sensor is enabled, it takes continuous distance measurements and uses a single digital output to indicate if it detects an object within its detection range. The output is driven low when the sensor detects an object; otherwise, the output is high. A camera with no IR filter shows the infrared light emitted by a Pololu Digital Distance Sensor. Please note that this sensor will only tell you if there is an object within the detection range along its line of sight, not how far away it is. As shown in the diagram above, there is hysteresis at the maximum range threshold to help ensure a clean transition as objects cross the threshold. The sensor can detect objects to within about 5 mm of the sensor face. Unlike simpler optical sensors that use the intensity of reflected light to detect objects, this sensor uses a short-range lidar module to precisely measure how long it takes for emitted pulses of infrared, eye-safe laser light to reach the nearest object and be reflected back. This allows the sensor performance to be largely independent of object reflectivity and ambient lighting conditions (though the range can be reduced for extremely low-reflectance objects). Some example applications include: break-beam sensor or photogate alternative non-contact bumper or obstacle detector for a robot non-contact interface element for activating a device or process a counter or timer of objects as they pass by Specifications Operating voltage: 3.0 V to 5.5 V Current consumption: 30 mA (typical) when enabled, 0.4 mA when disabled Maximum range: 5 cm (2″) Minimum range: < 5 mm Minimum update rate: 145 Hz (6.9 ms period) Field of view (FOV): 15° typical; can vary with object reflectance and ambient conditions Output type: digital signal (low when detecting an object, high otherwise) Dimensions: 0.85″ × 0.35″ × 0.122″ (21.6 × 8.9 × 3.1 mm); see the dimension diagram (191k pdf) for more information Weight: 0.014 oz (0.4 g) Using the sensor Three connections are necessary to use this module: VIN, GND, and OUT. These pins are accessible through a row of 0.1″-pitch through holes, which work with standard 0.1″ (2.54 mm) male headers and 0.1″ female headers (available separately). The VIN pin should be connected to a 3 V to 5.5 V source, and GND should be connected to 0 volts. The OUT pin drives low (0 V) when an object is being detected and it drives high (to the VIN level) when an object is not being detected. It is weakly pulled high when the sensor is disabled or waiting for its first reading to complete after power-up. A red LED on the back side of the board also lights whenever an object is detected. The board has an optional ENABLE pin that can be driven low to put it into a low-power state that consumes approximately 0.4 mA. This pin can be accessed through a via or its neighboring surface-mount pad on the back side labeled “EN” on the silkscreen. The ENABLE pin is pulled up to VIN, enabling the sensor by default. The board has one mounting hole intended for use with #2 or M2 screws. Jumper settings (irs16a) The board features four surface-mount configuration jumpers that determine its operation mode. Different versions of the Pololu Digital Distance Sensors ship with the appropriate jumpers pre-populated with 0 Ω resistors. These resistors can be desoldered from the populated spots or solder bridges can be added across the unpopulated spots to convert one sensor version into another. This sensor can be converted into any other irs16a version as listed in the following table. (For more information about how the different output types work, see the product pages for representative versions.) Item # Description Maximumrange* Hysteresis Resolution Minimumupdaterate Jumpersettings(4321) #4050 Digital output, 5cm 5 cm 16 mm - 145 Hz 0000 Digital output, 5cm (high sensitivity) 5 cm 16 mm - 65 Hz 0001 #4052 Digital output, 10cm 10 cm 20 mm - 115 Hz 0010 Digital output, 10cm (high sensitivity) 10 cm 20 mm - 30 Hz 0011 #4054 Digital output, 15cm 15 cm 24 mm - 95 Hz 0100 Digital output, 15cm (high sensitivity) 15 cm 24 mm - 15 Hz 0101 Digital output, 20cm 20 cm 28 mm - 70 Hz 0110 Digital output, 20cm (high sensitivity) 20 cm 28 mm - 15 Hz 0111 Digital output, 30cm 30 cm 36 mm - 37 Hz 1000 Digital output, 30cm (high sensitivity) 30 cm 36 mm - 15 Hz 1001 Digital output, any detect ~50 cm - - 50 Hz 1010 Digital output, any detect ~100 cm - - 15 Hz 1011 Pulse width output, 15cm max ~15 cm - 1 mm(= 4 µs) 145 Hz(190 Hz max) 1100 Pulse width output, 35cm max ~35 cm - 2 mm(= 4 µs) 95 Hz(165 Hz max) 1101 #4064 Pulse width output, 50cm max ~50 cm - 3 mm(= 4 µs) 50 Hz(110 Hz max) 1110 Pulse width output, 100cm max ~100 cm - 3 mm(= 4 µs) 15 Hz(110 Hz max) 1111 * Effective range depends on object reflectivity and ambient lighting conditions. Item numbers in this table indicate versions that we offer for sale as standard products, but we can manufacture the other versions on demand (or even make sensors with custom firmware for you). If you are interested in customization, please contact us. The Pololu Digital Distance Sensor family We have several different versions of Pololu Digital Distance Sensors, all with the same dimensions and pinout: Digital output(does not provide distance measurement) Sensor Maximumrange1 Minimumrange Minimumupdaterate Jumpersettings(4321) PCB ID Price #4050: Digital output, 5cm 5 cm < 5 mm 145 Hz 0000 irs16a $12.95 #4052: Digital output, 10cm 10 cm < 5 mm 115 Hz 0010 #4054: Digital output, 15cm 15 cm < 5 mm 95 Hz 0100 #4066: Digital output, 25cm 25 cm < 1 mm 100 Hz 0000 irs17a $17.95 #4067: Digital output, 50cm 50 cm < 1 mm 100 Hz 0001 #4069: Digital output, 100cm 100 cm < 1 mm 100 Hz 0011 #4077: Digital output, 200cm 200 cm < 1 mm 30 Hz 1011 Pulse width output(provides distance measurement) Sensor Maximumrange1 Minimumrange2 Resolution Minimumupdaterate Jumpersettings(4321) PCB ID Price #4064: Pulse width output, 50cm max ~50 cm 1 cm 3 mm 50 Hz 1110 irs16a $12.95 #4071: Pulse width output, 130cm max ~130 cm 4 cm 1 mm 100 Hz 0101 irs17a $17.95 #4079: Pulse width output, 300cm max ~300 cm 4 cm 2 mm 30 Hz 1101 1 Effective range depends on object reflectivity and ambient lighting conditions. 2 Objects closer than the minimum distance can still be detected, but the measured distance might be inaccurate. The minimum detection range is < 5 mm for irs16a boards and < 1 mm for irs17a boards. These are the output graphs for the digital output versions that just report if an object is in their detection range: The output graph is a bit different for the versions that use a pulse width to encode the measured distance. The output for these versions is similar to hobby servo control signals and is shown below as a function of time: Comparison to Sharp Digital Distance Sensors These Pololu Digital Distance Sensors have the same form factor and pinout as our carrier boards for the Sharp/Socle GP2Y0D8x digital distance sensors. They are available in the same 5 cm, 10 cm, and 15 cm ranges, in addition to longer ranges of up to several meters. This means they can be used as replacements for these older modules, which are based on sensors from Sharp/Socle that are no longer in production, and the longer-range versions can serve as upgrades that provide enhanced detection and measurement capabilities. The sensors on these newer units are much thinner than the Sharp modules, so the zero-range point is approximately 7 mm closer to the PCB, and the beam angle of the newer units is wider. The pictures below show side-by-side comparisons of the two:
