Automatic focusing device for reflected light microscopes

US4737022A · kind A · utility

Assignee

• Carl Zeiss Stiftung · DE

Inventors

• Bernd Faltermeier · Aalen, DE
• Reinhard Jorgens · Aalen, DE

Key dates

• Filing date: Jul 30, 1986
• Grant date: Apr 12, 1988
• Expiry date: Jul 30, 2006

Classification

• Technology area (CPC G): Physics
• CPC primary: G02B21/247
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

An automatic focusing microscope switchable between light-field and dark-field positions, so designed that the automatic focusing is operative in the dark-field condition or mode as well as in the light-field condition. In a first embodiment, auxiliary illumination of special wavelength (infrared or ultraviolet) used for the automatic focusing is reflected into the illumination-light ray path or beam, and in the dark-field mode the central portion of this beam is intercepted by a filter member which is opaque in the visible spectral region but transmits in the spectral region of the auxiliary illumination used for the automatic focusing function.