Sep 19 2014
The axicon lens is a specialized lens that bears a conical surface. The axicon lens images a point source as a line along the optic axis. A laser beam is transformed into a ring when it passes through an axicon lens. The term axicon was first coined by J.H. McLeod in the year 1954, meaning ‘axis image’ in Greek.
Pinhole camera and poisson spot are examples of axicon lens. An axicon may also be defined as a conical lens or a rotationally symmetric prism. An axicon produces either a line focus or projects a ‘ring’ spot. Commonly used axicons are converging lens-axicon doublets and diverging lens-axicon doublets.
Applications of Axicon Lens
Some of the typical applications of axicon lenses are listed below:
- Atomic traps – atomic traps that are formed using axicon lenses consist of an axicon mirror with a hole in the middle. The pushing beam pushes the atoms towards the hole. The counter propagating beam passes through the hole. A pulsed atom beam is created by turning the counter propagating beam on and off.
- Optical coherence tomography
- Corneal surgery – a combination of negative and positive axicons are used to alter the diameter of the ring for ablating the corneal material.
- Acoustic testing
- Linear accelerators
- Solar concentrators
- Axicon resonators in lasers
Sources and Further Reading
- The Axicon? – University of Arizona
- Spherical Aberration Effects in Lens-axicon doublets – University of Tennessee Space Institute