101: Laser Distance Measurement

1. 101: Laser Distance Measurement Just like with everyday communication, you cannot understand tech language if you haven’t grasped the basics. The realm of laser distance measurement is one of the most understood subjects in the tech world, and this can sometimes make it challenging for buyers. Sensor applications where there’s need for a small light spot and where the distance capabilities of background suppression are exceeded are best left for laser distance sensors. Attributes of Laser Distance Measurement Sensors Absolute Accuracy: This can be defined as the maximum attainable difference between the sensor’s measured distance and the actual physical distance. Laser distance measurement gadgets use this value as the worst case scenario since there factors that must be taken into consideration including the product factors, tolerance levels between similar models of sensors and the various applications. Putting absolute accuracy in applications, if a sensor reading is 2300 mm distance to a target audience and has an absolute accuracy of 5 mm you can measure this distance physically to within 5 mm using a tape measure. Resolution: This is the total change in position that’s necessary for a sensor to record a difference in its output. For example, if you change the position of an object in front of a laser distance measurement sensor by 0.01 and there’s no difference recorded in the analog output (remains 4.51 mA) then it must be having a resolution that’s greater than 0.01mm. Resolution communicates the amount of incremental distance that will be changed by the output, although it can’t tell you the quality of the sensor measurement. Repeatability: This is sometimes called repeat accuracy and shows the capability of a sensor in giving consistent output at the same distance. For example, if the output in a sensor is indicated as 500mm away, moving the object towards the object severally should bring the output will bring a reading of X mm of 500mm. If say we give X a value of 5 mm, a subsequent measurement of the laser distance will result in a value of 498 mm, another one will show 501 mm and a fourth measurement will show 506 mm. As you can see value rage is 5 mm of the previous measurement. The value of X is therefore the repeat accuracy. Summary Repeat accuracy is the most valued attribute for many applications of distance measurement. It indicates the number of times the object measurement must be done (repeatability) in order for the objects position to be known. So, what’s the take away? Absolute accuracy is maximum achievable distance between the measured distance and the physical distance. Repeat accuracy is the consistency of the output results for the same target object and capacitive proximity sensors. And resolutions shows the distance required for an object to move in order to record a difference in the output.