Sensitivity of quadrant detectors to Bessel beams

Abstract

We investigate the sensitivity of a quadrant detector to a Bessel beam. The expression for the response and sensitivity of the quadrant detector to the Bessel beam is hard to evaluate analytically due to the non-integrable nature of the Bessel function, which describes the Bessel beam. Simulations show that the sensitivity for the infinite-ringed Bessel beam is lower than the Gaussian beam for small displacements. However the sensitivity decays more slowly than that of the Gaussian beam. Thus, the Bessel beam has a greater beam tracking range than the Gaussian beam. Furthermore, limiting the rings of the Bessel beam increased the sensitivity in the small displacement region but decreased the beam tracking range. The 1-ringed Bessel beam had a higher sensitivity than the Gaussian beam in the small displacement region. The Bessel beam can be used in applications that require a wide range of beam tracking where the displacement of the beam is large. For precise measurements, the sensitivity can be increased by truncating the Bessel beam or by reducing the beam waist.