Illumination device using a pulsed laser source a Schlieren optical system, and a matrix addressable surface light modulator for producing images with undiffracted light

US5495280A · kind A · utility

Assignee

• Max-Planck-Gesellschaft zur Föderung der Wissenschaften e.V. · US

Inventors

• Andreas Gehner · Duisburg, DE
• Gunther Hess · Linz, AT
• Heinz Kück · Stuttgart, DE
• Holger Vogt · Mülheim, DE

Key dates

• Filing date: Jun 17, 1994
• Grant date: Feb 27, 1996
• Expiry date: Jun 17, 2014

Classification

• Technology area (CPC G): Physics
• CPC primary: G03F7/70358
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

An illumination device used for the direct illumination of light-sensitive ayers comprises a light source and a pattern generator. The pattern generator includes an optical Schlieren system and an active, matrix-addressable surface light generator. The Schlieren system comprises a Schlieren lens and a projection lens as well as a mirror device, which is arranged between these lenses and which directs light coming from the light source onto the surface of the surface light modulator. A filter device is used for filtering out diffracted light and for permitting undiffracted light to pass from the surface light modulator to the projection lens. The structure to be illuminated is secured in position on a displaceable positioning table. The surface light modulator is addressed such that the non-addressed surface areas thereof correspond to the projection areas of said structure which are to be illuminated.