Generalized optical design of the multiple-row circular multi-pass cell with dense spot pattern

Area of Science:

• Optics
• Optical Engineering
• Laser Physics

Background:

• Traditional multi-pass cells (MPCs) have limitations in optical path length and path-to-volume ratio.
• Existing designs often struggle to achieve high path density within a compact volume.

Purpose of the Study:

• To present a generalized method for designing novel circular multi-pass cells (MPCs).
• To enhance the overall optical path length and path-to-volume ratio compared to traditional designs.
• To enable precise control over the distribution of reflection spots.

Main Methods:

• Exploiting the vertical dimension of cavity mirrors in a circular MPC design.
• Utilizing two easy-fabricating circular spherical mirrors to create multiple rows of reflection spots on different horizontal planes.
• Calculating and simulating q-preserving configurations for probe Gaussian beams.

Main Results:

• Achieved multifold overall optical path length and enlarged path-to-volume ratio.
• Demonstrated arbitrary control over the interval of reflection spots in horizontal and vertical directions.
• Simulated a maximum optical path length of 201.8 m within 427.2 mL.
• Presented a practical setup with 21.9 m optical path length within 100.1 mL, the smallest volume for similar path lengths.

Conclusions:

• The novel circular MPC design offers a significant improvement in optical path length and path-to-volume ratio.
• The method allows for dense, regular spot patterns and efficient light path arrangements.
• This design represents a breakthrough in compact, high-performance optical cell technology.