Application Cases

Experiment Name: Wavefront Correction Experiment Based on SPGD AO System

Experimental Purpose:
To investigate the feasibility of applying the SPGD AO system for extracavity laser beam purification through experimental methods. An SPGD AO system was first established in the laboratory, followed by correction experiments targeting dynamic wavefront distortions actively introduced by a deformable mirror and those generated by artificial turbulence, thereby validating the corrective capability of the SPGD AO system.

Test Equipment:
Voltage amplifier, wavefront sensor, tip-tilt mirror, deformable mirror, computer, etc.

Experimental Process:

Figure 1: Schematic Diagram of the Conjugate Adaptive Optical System Structure

The adaptive optical system is used to demonstrate laser transmission with beacon assistance, and its schematic structure is shown in Figure 1. The two collimators have identical structures, each equipped with a He–Ne laser, spatial filtering device, large-aperture long-focus lens, and a simulated camera. A laser with a diameter of 2 mm and a wavelength of 632.8 nm passes through the spatial filtering device and the large-aperture long-focus lens, exiting the collimator with an expanded diameter of 110 mm. Simultaneously, the collimator can receive parallel light and focus it onto the simulated camera via the lens. The clear apertures of the tip-tilt mirror and deformable mirror are 140 mm and 100 mm, respectively, both requiring high-voltage DC drives during operation. The main control computer manages the startup and shutdown of the high-speed processor, which serves as the core of the electronic control system. Its functions include: capturing CCD digital images from the Shack–Hartmann wavefront sensor via an image acquisition card, calculating the slope matrix and reconstructing the wavefront, computing control signals, performing D/A conversion since these signals are digital, and finally outputting analog control signals. The voltage amplifier is responsible for amplifying the analog control signals from the processor into high-voltage DC to drive the tip-tilt mirror or deformable mirror, enabling corresponding adjustments. The diagnostic computer analyzes the far-field spots of the beacon and main laser to evaluate changes in beam quality before and after the adaptive optical system is closed-loop.

Experimental Results:
An SPGD AO experimental system was successfully established and utilized for beam purification simulations in high-energy lasers and wavefront distortion correction experiments under artificial turbulence. The system demonstrated significant improvements in the Strehl Ratio and effective correction of low-order Zernike modes, validating its robustness in handling dynamic wavefront distortions.

Recommended Voltage Amplifier: ATA-2082

Figure: ATA-2082 High-Voltage Amplifier Specifications

This document has been compiled by Aigtek. For more application cases and detailed product information, please stay tuned. Xi’an Aigtek Electronics has become a large-scale instrument and equipment supplier with an extensive product line in the industry. Demo units are available for free trial.