Laser scanning galvanometer performance detection method

Abstract

The invention discloses a laser scanning galvanometer performance detection method, and the method comprises the specific steps: enabling a system to be powered on, forming a linear light source, enabling the linear light source to irradiate a galvanometer, and enabling the linear light source to irradiate a photosensitive surface of a detector after reflection and focusing through a focusing lens; defining a working zero point; determining a scanning frequency, an average frequency and a scanning period according to the time elapsed by three adjacent working zero crossing points; determininga linear segment time utilization rate according to the percentage of the obtained linear segment experience time in the scanning period; calculating an average value of the obtained effective swing angles of the linear segments to obtain effective swing angles of the linear segments; according to the working characteristics of the detector and the ratio of the distance between adjacent sampling points to the elapsed time, obtaining the instantaneous speed and the average speed, and calculating the maximum speed deviation. The invention provides a method for detecting the performance of a laser scanning galvanometer, and the method can improve the imaging stability, guarantees the uniformity of a swing angle, and achieves the precise measurement of dynamic scanning parameters.

Description

technical field [0001] The invention relates to the technical field of optical precision measurement, in particular to a method for detecting the performance of a laser scanning vibrating mirror. Background technique [0002] The high-frequency and high-precision galvanometer is a key component of the linear scanning imaging system. Parameters such as the linear characteristics of the oscillating mirror seriously affect the scanning and imaging quality, while the repeatability of the oscillating affects the imaging stability. [0003] With the development of laser scanning technology, the application of laser scanning galvanometer is more and more extensive, such as laser internal engraving, laser marking, laser radar and other fields, laser scanning galvanometer has played an important role, the performance requirements of laser scanning galvanometer Higher and higher. At present, the commonly used methods for measuring the characteristic parameters of the galvanometer inc...

AI Technical Summary

Problems solved by technology

The circular grating angle measurement method uses moiré fringes to measure the angle that the galvanometer rotates. It has high measurement accuracy, fast speed, and strong anti-interference ability. However, because this method needs to install a circular grating structure on the galvanometer as an auxiliary, it cannot achieve non-contact Measurement; laser interferometry uses the optical path difference between the measurement beam and the reference beam caused by the rotation angle of the galvanometer to measure the angle of rotation of the galvanometer. The measurement accuracy is high, but fisheyes or Angle prism and other auxiliary devices, so it will affect the dynamic performance of the vibrating mirror; the principle of the reflective high-precision differential small swing angle goniometric method is to place two reflectors in the transmission and reflection directions of the beam splitter, using two The change of the reflectivity of a mirror (which changes with the angle of incidence) is used to measure the size of the angle of incidence. This method can realize non-contact measurement and high-speed measurement, but because the linear relationship between reflectivity and angle of incidence is only established near the critical angle , which limits its measurement range, it is often necessary to use other angle measuring equipment for rough measurement in use, and the measurement efficiency is low

The autocollimation goniometric method uses the object-image relationship characteristics of the optical system to measure the angle of the incident light. It can measure two-dimensional angles and is non-contact measurement. However, its angle measurement range is small and the frequency response is low, so it is difficult to apply in the galvanometer test.

Images