Random spherical microlens array fabricated by elliptical vibration diamond cutting and molding

Area of Science:

• Optics and Photonics
• Materials Science
• Manufacturing Engineering

Background:

• Microlens arrays (MLAs) are crucial for laser beam homogenization, offering excellent optical properties.
• Traditional MLAs (tMLAs) suffer from interference effects that degrade homogenized spot quality.
• Random MLAs (rMLAs) were developed to mitigate interference during homogenization.

Purpose of the Study:

• To propose and demonstrate a method for mass production of high-quality random microlens arrays (rMLAs).
• To investigate rMLAs with randomness in both period and sag height for improved optical homogenization.
• To validate the performance advantages of the designed rMLA.

Main Methods:

• Design of rMLAs with random period and sag height.
• Ultra-precision machining of S316 molding steel using elliptical vibration diamond cutting for MLA molds.
• Fabrication of rMLA components via molding technology.
• Optical performance verification using Zemax simulation and homogenization experiments.

Main Results:

• Successful ultra-precision machining of MLA molds on S316 steel.
• Precise fabrication of rMLA components using molding technology.
• Zemax simulations and experimental results confirmed the superior performance of rMLAs over tMLAs in reducing interference and improving spot quality.

Conclusions:

• The proposed method enables mass production of advanced rMLAs for high-quality laser beam homogenization.
• Randomization in MLA period and sag height effectively reduces interference effects.
• The developed rMLA technology offers significant advantages for optical homogenization applications.