A laser rangefinder, also called an LRF or LIDAR, is an electronic device that uses the light emitted from a laser to measure distance. In its most common form, it is incorporated into hand-held devices for DIY enthusiasts to measure the size of a room in a house. But this application is just the tip of a very big iceberg for LRF technology, and LightWare focusses on more sophisticated, and more profitable, markets.Did we answer your question ?
Beam divergence is an angular measure of the increase in laser beam diameter over distance from the point where the laser beam exits the optics.
Most LightWare rangefinders have a beam divergence of less than 0.2°. This may vary slightly across products.
Simply put the beam pattern starts out as a square shape about the size of the lens and then slowly expands in all directions, becoming approximately circular in shape.
Beam divergence may be different on different axes.
The actual shape of the beam depends on many environmental factors, as well as energy dissipation around the edges of the beam, so a precise pattern cannot be predicted.
The attached graph gives an estimate of the nominal beam diameter at the half power points over the range:Did we answer your question ?
In bright lighting conditions it is possible for readings to become slightly erratic or false results are displayed when there is no signal. This can be corrected as follows:
• Connect the SF30 to a PC or laptop using the USB cable only
• Press the <SPACE> key to stop readings from being taken and to show the main menu
• Press the capital <U> key to unlock the factory settings
• Press the capital <Y> key to confirm the unlocking command
• Press the arrow right key twice until the menu titled ** APD Settings ** is visible
• Write down the voltage value shown in the selection 1: APD breakdown xxx.xV
• Calculate a new breakdown voltage by subtracting 2 volts from the current value
• Enter the new breakdown voltage by pressing the <1> key then typing in the number followed by the <ENTER> key
• Check that the new value is entered correctly and has a value that is 2 V below the original value
• Press the <ESC> key to return to normal measuring
• Check that the readings are now stable and that there are no false results
• If there is still some noise repeat the steps above and reduce the APD breakdown by another 2 volts
The solution below may be of use in the event that the LightWare Terminal program cannot connect to the laser rangefinder due to a com port error.
Windows allocates a com port to every device connected, but does not ever clear these allocations. This means that Windows will run out of available com ports once 255 ports have been allocated, requiring a clearing of the allocated com ports.
The below steps will show you how to easily clear the com ports using the LightWare Termminal program.
Reading altitude off a water surface is quite challenging, especially during bright sunshine. The laser signal can be lost within the water and sunshine reflecting off the water surface causes noise and false readings.
LightWare suggests changing the rangefinder’s settings before flying over water. This can be done either through the user manual or in flight, using the extensive command sets available for serial and I2C communication.