Pololu Distance Sensor with Pulse Width Output, 50cm Max
This small lidar-based distance sensor reports the distance of objects up to about50cm (20″)away with a pulsed signal similar to a hobby servo control signal. A digital microcontroller pin can be used to time the length of each high pulse, which encodes the measured distance. The sensor works over an input voltage range of 3.0V to 5.5V, and the 0.1″ pin spacing makes it easy to use with standard solderless breadboards and 0.1″ perfboards.
The relationship between measured distanced(in mm) and pulse widtht(in µs) is as follows:
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The timing uncertainty is approximately ±5%. As objects approach the sensor, the output pulse width will approach 1.0ms, while an object detected at 50cm will produce a 1.667ms pulse width. The sensor uses a pulse width of 2.0ms to indicate no detection. The pulse periodTranges from around 9ms to 20ms, depending on the proximity of the detected object.
The maximum detection range depends on object reflectivity and ambient lighting conditions. In our tests, the sensor was able to reliably detect a white sheet of paper out to around 50cm away, and it could reliably detect a hand out to around 30cm away. The following graph shows the measured distances of five units versus their actual distances from a white paper target at several different ranges:
Please note that while this sensor can detect objects to within about 5mm of the sensor face, the effective minimum distance it can measure is around 1cm, so objects closer than 1cm might result in an inaccurate measurement.
Specifications
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Operating voltage: 3.0V to 5.5V
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Current consumption: 30mA (typical) when enabled, 0.4mA when disabled
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Maximum range: approximately 50cm (20″) (for high-reflectivity targets in good ambient conditions; lower-reflectivity targets or poor ambient conditions will reduce the maximum detection range)
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Minimum range: 1cm (for accurate measurement); <5mm (for detection)
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Update rate: 50Hz to 110Hz (20ms to 9ms period)
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Field of view (FOV): 15° typical; can vary with object reflectance and ambient conditions
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Output type: digital pulse width
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Dimensions: 0.85″ × 0.35″ × 0.122″ (21.6 × 8.9 × 3.1 mm); see thedimension diagram(191k pdf) for more information
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Weight: 0.014oz (0.4g)
Dimensions
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Size: |
0.85″ × 0.35″ × 0.122″ |
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Weight: |
0.4 g |
General specifications
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Resolution: |
3 mm |
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Maximum range: |
50 cm1 |
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Sampling rate: |
50 Hz2 |
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Minimum operating voltage: |
3.0 V |
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Maximum operating voltage: |
5.5 V |
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Supply current: |
30 mA3 |
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Output type: |
digital pulse width |
