Phase Imaging in Plant Cells and Tissues - Biomedical Optical Phase Microscopy and Nanoscopy - page 51

CHAPTER 4
Phase Imaging in Plant Cells and Tissues
Vassilios Sarafis
Botany School University of Melbourne, Vic, Australia
Mathematics and Physics School, University of Queensland, Brisbane St Lucia, QLD, Australia
Biomedical Science and Engineering School, University of Adelaide, SA, Australia
Birla Institute of Technology and Science, Hyderabad, Andhra Pradesh, India
Editor: Zeev Zalevsky
Phase imaging in plant cells and tissues depends on the boundaries between places where
concentration of water is different or there is a boundary between water and oil containing
compartments. This chapter has listed 10 microscopy methods to make the boundaries to be
visible to the human eye so that they can be well studied. These methods can be applied for
transparent specimens of different characteristics.
The out of focus imaging is the first and the earliest method that produces contrast at the
boundary of the specimen using the out of focus approach.
The dark field microscopy creates dark background around the specimen using the
elimination of the unscattered beam from the image of the specimen.
The phase contrast techniques, presented Chapter 1, allow a living specimen to be studied
due to its exclusion of staining showing the boundaries where refractive index changes.
There are also other types of contrast microscopy. One is to use Becke line test to create
contrast between the boundaries of specimens. Differential contrast microscopy (DIC),
presented in Chapter 2, is another type of contrast microscopy. It uses the interference of
dual polarizations to form visible images of specimens due to the phase difference. Also,
the Hoffman modulation contrast (HMC) microscope is able to vary the contrast of different
regions within a specimen using its phase gradients.
The adaptive optics microscopy, on the other hand, uses adaptive optics elements such as
deformable membrane mirror (DMM) or spatial light modulators to optimize the image
quality of the specimen, usually in fluorescence.
The interferometric microscopy, also uses phase contrast technique with the addition of a
spatial light interference microscopy (SLIM) module to capture the image of a specimen.