The application of optical techniques in aspheric surface assessment

✍ Scribed by David M.G. Stevens

• Publisher: Elsevier Science
• Year: 1992
• Tongue: English
• Weight: 356 KB
• Volume: 32
• Category: Article
• ISSN: 0890-6955
• DOI: 10.1016/0890-6955(92)90055-l

✦ Synopsis

During the last decade, there has been a dramatic increase in the number of aspheric optical systems generated. Two large contributors to this are the Compact Disc Lens' focusing system and the Ophthalmic contact lens industry. The requirement for faster and more accurate methods of quality control has increased proportionally.

The paper briefly discusses methods of manufacturing such complex forms, measurement methods available and describes a unique system for assessing the absolute form error, forming an open loop feedback sys;;em to the manufacturing cell.

Reference to the Form Talysurf Laser Interferometric measurement system will be made, with a full description of gauging technology utilised. The implementation of the Michelson Interferometer and necessity for arcuate correction of the stylus tip in a pivoted arm arrangement will be described.

The general aspheric form will be discussed which emphasises the need for Form and Surface Texture analysis.

The paper then proposes methods of analysis that may be necessary in the future for aspheric and other complex forms.