Dark Field Illumination0 pages

 
Optilia Instruments AB

High Quality, Flexible Visual Inspection Systems 

Dark Field Illumination
Dark field illumination excludes the unscattered beam from the image. It works by illuminating the
sample with light that will not be collected by the objective lens, and thus will not form part of the
image. As a result, the field around the specimen (i.e. where there is no specimen to scatter the
beam) is generally dark but the objects that scatter the illumination beam are bright.
Dark field microscopy is a simple yet effective technique and well suited for following applications:
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Live and unstained biological samples, such as water-borne single-celled organisms.
Cellular analysis or samples that have not gone through the
staining process.
Precision unstained plastic parts.
Fibers, hairs, yeast and protozoa.
Minerals and crystals, thin polymers and some ceramics.
Forensics and latent fingerprint.
Examining external details, such as outlines, edges, grain boundaries and surface defects. 

W20x-HD camera with +5 lens

Scattered, image forming
rays
Unscattered rays
Unstained Object

Working
Distance

Object plane

Oblique Illumination beam

Dark-Field Illuminator

 
RevA, April 2012