High Precision Position Measurement Method for Laguerre-Gaussian Beams Using a Quadrant Detector

Abstract

In this paper, we propose a new method to improve the position measurement accuracy for Laguerre-Gaussian beams on a quadrant detector (QD). First, the error effects of the detector diameter and the gap size are taken into account, and the position error compensation factor is introduced into the conventional formula. Then, in order to reduce the number of parameters, the concept of effective radius is proposed. Thus, a new analytical expression is obtained with a best fit using the least square method. It is verified by simulation that this approach can reduce the maximum error by 97.4% when the beam radius is 0.95 mm; meanwhile, the root mean square errors under different radii are all less than 0.004 mm. The results of simulation show that the new method could effectively improve the accuracy of the QD measurement for different radii. Therefore, the new method would have a good prospect in the engineering practice of beam position measurements.

Simultaneous position prediction and intensity correction of quadrant detector-based detection system

“…The incident laser converges through an optical system to form a diffuse light spot. After fitting the light field distribution, it can be regarded as a Gaussian distribution, and the concentration of the light field distribution is described by the Gaussian radius; As the Gaussian radius decreases, the light field distribution becomes more concentrated [10].…”

Indoor Visible Light Positioning: Overcoming the Practical Limitations of the Quadrant Angular Diversity Aperture Receiver (QADA) by Using the Two-Stage QADA-Plus Receiver

“…A quadrant PD is made up of four individual PDs closely arranged in a 2 × 2 grid, with a small gap separating the quadrants. Unlike conventional applications, such as atomic force microscopy [ 27 ], that use quadrant PDs with laser light [ 28 ], our innovative use of an aperture means that QADA can be used with standard indoor illumination.…”

Nonlinear optical responses of all-inorganic lead halide perovskite nanostructures by time-resolved beam-deflection technique

“…Actual time resolution of about 20 µs achieved in our experiments is limited by the shutter speed. The position coordinate (x, y) of the laser beam spot on the QPD is given in an arbitrary unit 64,65…”