3898 x 2598 px | 33 x 22 cm | 13 x 8,7 inches | 300dpi
Aufnahmedatum:
25. April 2016
Weitere Informationen:
Köhler illumination is a method of specimen illumination used for transmitted and reflected light (trans- and epi-illuminated) optical microscopy. Köhler illumination acts to generate an extremely even illumination of the sample and ensures that an image of the illumination source (for example a halogen lamp filament) is not visible in the resulting image. Köhler illumination is the predominant technique for sample illumination in modern scientific light microscopy. It requires additional optical elements which are more expensive and may not be present in more basic light microscopes. The primary limitation of critical illumination is the formation of an image of the light source in the specimen image plane. Köhler illumination addresses this by ensuring the image of the light source is perfectly de-focused in the sample plane and its conjugate image planes. In a ray diagram of the illumination light path this can be seen as the image-forming rays passing parallel through the sample.