UV-capable dry lens for microscopes

US5103341A · kind A · utility

Assignee

• Carl Zeiss Stiftung · DE

Inventors

• Wilhelm Ulrich · Aalen, DE
• Franz Muchel · Oberkochen, DE

Key dates

• Filing date: May 15, 1990
• Grant date: Apr 7, 1992
• Expiry date: May 15, 2010

Classification

• Technology area (CPC G): Physics
• CPC primary: G02B21/02
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

An UV-capable dry objective for microscopes in which aperture aberration is corrected, at the same time, both for the visible spectrum and for a selected UV-wavelength. The objective comprises two lens groups separated by an air gap which is varied in size by relative movement between the two lens groups. The size of the air gap is adjusted to correct aperture aberration for the selected UV-wavelength. The objective is designed so that the mathematical sign is the same for both (i) the corrections required as the illumination moves toward the longer-wave portion of the visible spectrum, and (ii) for the corrections required as the illumination moves toward the shorter-wave portion of the UV-spectrum. The objective has an aperture of at least 0.7 and a magnification of more than 60.times..