Organic abrasive machining system for optical fabrication with 0.1-mm spatial resolution

Area of Science:

• Optics and Photonics
• Materials Science
• Manufacturing Engineering

Background:

• High-precision optics for short-wavelength applications (X-rays, EUV) demand nanometer-level surface accuracy.
• Conventional numerically controlled machining struggles with mid-spatial-frequency errors due to limited spot size.

Purpose of the Study:

• To develop and demonstrate a high-spatial-resolution figure correction technique for precision optics.
• To investigate the Organic Abrasive Machining (OAM) technique for addressing limitations in current optical finishing processes.

Main Methods:

• Development of an Organic Abrasive Machining (OAM) apparatus with integrated machining load measurement.
• Utilizing a 100 µm machined spot generated by an elastic rotation tool in an acrylic particle slurry.
• Investigating the influence of machining and slurry parameters on the process.

Main Results:

• Demonstrated high-spatial-resolution machining on a flat glass substrate.
• Achieved a root-mean-square surface roughness below 0.2 nm after OAM processing.
• Successfully fabricated patterns with a minimum line and space size of 100 µm.

Conclusions:

• The OAM technique is effective for high-spatial-resolution figure correction of precision optical surfaces.
• OAM overcomes limitations of conventional methods in removing mid-spatial-frequency errors.
• The developed OAM apparatus and process enable the fabrication of intricate patterns with excellent surface quality.