Microscopy, optical bright field

Phase-contrast microscopy. In bright-field illumination, variations in optical absorption within the specimen give rise to an image which consists... 

Fig. 8. Concentration dependence of ultrasound backscatter signal by plates coated with a layer of targeted microbubbles. Surface concentrations of microbubbles (as observed by bright-field optical microscopy, bottom) increase from left to right. Imaging performed using a fundamental frequency scheme. Samples placed on top of an ultrasound tissue phantom. Reprinted from Advanced Drug Delivery Reviews v. 37, A.L. Klibanov, Targeted delivery of gas-filled microspheres, contrast agents for ultrasound imaging, p. 145. Copyright, 1999, with permission from Elsevier Science...

Figure 2. Pitch coke 500°C75% l.telectron micros-copy on a section from the block observed by optical microscopy X 1800 photomontage (a) in bright field (b) in dark field...

Bright-Field Illumination A kind of illumination for microscopy in which the illumination of a specimen is arranged so that transmitted light remains in the optical path of the microscope and is used to form the magnified image. This is different from the arrangement in Dark-Field Illumination. 

Then, microscopic examinations follow optical research microscopes allow to determine the number, thickness, and color sequence of layers in paint fragments, and to recognize the textures as well as fundamental features of pigment and extender mixtures. Bright field and dark field illuminations, polarized light microscopy (incident and transmitted), particularly the differential interference contrast (DIC) procedure, and fluorescence microscopy are necessary for paint examinations (see Figure 3(A)-3(E)). 

The bright field (BF) method is used most often in optical microscopy. In this method, details of the sample appear either light or dark, as determined by their respective positions in relation to the incident light ray, and by their optical properties. In order for adjacent regions of the sample to be distinguished from one another, the difference between their reflectivity values must be at least 10%. 

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