Spatial filter pinhole image acquisition based on beam self-fold back in a multi-pass amplifier laser system.

Area of Science:

• Optics and Photonics
• Laser Technology
• High-Energy Physics

Background:

• High-energy multi-pass laser systems require precise beam alignment for operation.
• Accurate alignment relies on high-precision reference acquisition, particularly imaging the final-pass pinhole.
• Existing methods for pinhole collimation can be complex and affected by multi-stage amplification.

Purpose of the Study:

• To introduce a new method for imaging reference pinholes in multi-pass laser amplification systems.
• To simplify and enhance the precision of laser beam collimation in high-energy systems.
• To eliminate the need for additional light sources in the alignment process.

Main Methods:

• A rectangular prism is inserted into the laser beam path.
• The prism utilizes total internal reflection to redirect the pilot beam.
• The redirected beam directly illuminates the reference pinhole, bypassing intermediate amplification stages.

Main Results:

• A clear boundary image of the reference pinhole is obtained.
• The method effectively images the final-pass pinhole without introducing new light sources.
• The technique simplifies the collimation process, reducing the impact of multi-stage amplification.

Conclusions:

• The proposed prism-based method offers a rapid and precise solution for collimating multi-path optical systems.
• This approach significantly aids in the alignment of intense laser systems.
• It mitigates the complexity associated with traditional multi-stage pinhole collimation techniques.