Laser pointer safety distances
Laser beams spread out over a distance. The green numbers
in this table show how far a legal laser pointer
beam will travel (in feet), before
it spreads out so much that the power entering an eye falls below a
given safety level.
Table and graphics ©2005, Pangolin Laser Systems. All rights reserved. See detailed copyright notice below.
The laser power levels in this table have been selected based on three factors:
The distance shown is the "slant range", directly from the laser to an aircraft. If the beam is at an angle, this is NOT the distance along the ground, or the altitude.
Calculations assume uniform beam profile (top hat), not gaussian profile. If calculated for gaussian (TEM00) beams, the distances would be a bit longer in some cases.
Actual exposure values would be less due to atmospheric attenuation and scattering. Values given here are therefore conservative (erring on the side of safety).
Beam diameter at the source is basically immaterial due to its small size compared to the spot size at a significant distance
Very short distances in the table will be more conservative than actual, due to disregarding of initial beam diameter. This effect is insignificant at longer distances.
Data in this table is for relative comparisons only. Due to a variety of variables, safety distances for specific installations or uses need to be calculated by qualified personnel.
Calculations and data provided by Casey Stack, Laser Compliance Inc.
Table design and production by Patrick Murphy, who is responsible for any errors of data or presentation. (Please contact him with any corrections or suggestions.)
Funding and support by Pangolin Laser Systems, Inc.
The table and the laser-airplane graphic are copyrighted ©2005 by Pangolin Laser Systems. All rights reserved. You may freely link to this page. However, permission is required to copy or reprint the table and/or the laser-airplane graphic; contact Pangolin for more information.