Laser Ranging

There are two types of laser ranging; time of flight and angular measurement.
With a known distance between the sensor and laser diode the angle between outgoing beam and reflection can be measured.

These sensors have a limited range with a range of e.g. 10-60cm or 20-150cm. Different ranges and interface types (analog or digital) are available and a lot of the robotics/electronics webshops have some of these sensors.

Time of flight sensors use a different approach. These sensors send out a short pulse of light using a laser diode and the time needed for the light to travel from sensor to object and back is then measured.
These sensors have a much wider range than the PSD type of sensors. A range from 1-9m or even up to 100m is not uncommon. Unfortunately these sensors have a very high price, single point sensors are easily in the USD 700,- to 1500,- and scanning/rotating sensors (known as LIDAR sensors) are USD 2500,- to 5000,- or higher.

Lightware developed a sensor that carries just the analog front end and optics to make time of flight sensors available for the hobby market. For the small price of USD 150,- one can now play around with ToF measurements. Since this sensor contains just the analog front end this is something that is only for those who have good skills in embedded development! It is not as easy as buying a sensor, adding an Arduino library and you're done...


The sensor from Lightware is the OSLRF-01 with OSLRF meaning Open Source Laser Range Finder. Schematics and a user manual are available as download from that page.