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CHAPTER 11
Tissue Imaging with
Coherent Anti-Stokes
Raman Scattering
Microscopy
Eric Olaf Potma
Department of Chemistry & Beckman Laser Institute
University of California
Irvine, California
As spontaneous Raman spectroscopy has blossomed and grown during
one-half century, it may be predicted with some confidence that coherent
nonlinear Raman spectroscopy will yield many new results in the next
half century.
Nicolas Bloembergen, 1978
11.1 From Spontaneous to Coherent Raman
Spectroscopy
Sir Chandrasekhara Venkata Raman was justifiably excited when he
noticed that if a monochromatic light beam is passed through a simple
transparent liquid, different colors can be detected in the scattered
light. Raman called this frequency shifted scattered light “a new type
of secondary radiation,” because he realized that the phenomenon he
discovered was caused by a molecular property different from the
1
property of fluorescence emission. Since Raman’s early work in 1928,
it has been well established that molecular vibrations are responsible
for the observed frequency shifts in the scattered light. The discovery
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