Generation of Adjustable Bottle Beams Using an Axicon

The bottle beams generated by using a conical-lens system are investigated theoretically and experimentally.The evolutions of bottle beams are illustrated simply by using geometrical structures and the paraxial ray tracing.Our study results show that the bottle beams with a dark focus surrounded by regions of higher intensity,are dependent not only on the focal length of the focal lens,but also on the radius of limiting aperture and the distance between the axicon and the lens.For a fixed axicon,we show that the radius of the dark focus of the bottle beam is proportional to the focal length of the focal lens.And the longitudinal length of the dark focus is inverse proportional to the distance between the axicon and the lens and the radius of limiting aperture.It is shown that by changing the focal length of focal lens and the distance between the axicon and the lens,the center of dark of the bottle beams can be altered effectively.