The Structured Laser Beam represents a new paradigm in the creation of non-diffractive beams (NDBs) and it has the potential to greatly improve a number of mainstream applications using laser beams or light beams.
With a very low divergence that keeps the spot size within a few millimetres even at distances of hundreds of metres (with a beam waist of a few µm right after the output of the system), this beam may enable lasers to be used for applications not previously possible, or improve precision within existing applications.
NDBs are frequently used today, primarily by the use of axicons. These can only generate NDBs over a small portion of the beam, typically limited to a few tens of centimetres. The Structured Laser Beam is able to generate an NDB over hundreds of metres, with lower costs. It is therefore possible to envision the application of this beam in applications where NDBs are not typically used today; either in other laser/light beam applications as mentioned above, or entirely different fields. In addition, the Structured Laser Beam exhibits other properties, unique to this beam, and of benefit to other applications.
- Extremely compact spot size and very low divergence
- Vast improvement in distance over present-day Structured Beams
- Self-reconstruction after obstacles
- Very robust to jitter, vibrations, and variations in the angle of the input beam; it also shows some robustness to fluctuations in air temperature
Possible Application Areas
- Satellite communication
- Gas detection
- Optical tweezers
- Laser show
Due to the unclarified IP status, the system can only be presented as a black box. The physical dimensions of the prototype are approximately those of a matchbox. The input is a regular Gaussian laser beam, the output is a short- and long-distance NDB. The dimensions are not absolute: it should be possible to achieve a much smaller system.
The invention is a novel method of generating a structured/non-diffractive beam over large distances:
- Like a Bessel beam, our beam is self-reconstructing
- Depending on the setup, the system is very robust with respect to the incoming beam. An angular displacement of the input beam gives a much smaller (tested up to a factor 100+) angular displacement in the output beam
- Our beam is composed by an inner central spot with high intensity, surrounded by concentric rings with particularly clear contrast between them, compared to conventionally produced structured beams
- The diameter and number of rings can be tuned over a wide range
- Central spot with much smaller diameter than for conventional Gaussian laser (20 µm against 800 µm at three meters)
- Intensity is decreasing with the square of distance from the source