Holographic Microscopy Techniques for Multifocus Phase Imaging of Living Cells - Biomedical Optical Phase Microscopy and Nanoscopy - page 95

the wave front of the object wave. The interferogram that is formed by the superposition of
object wave and reference wave is recorded by a charge-coupled device (CCD) camera and
transferred to an image processing system for reconstruction and evaluation of the digitized
holograms.

6.2.2 Self-Interference DHM

A drawback of many Mach Zehnder-interferometer-based quantitative phase imaging
arrangements [7,9 11,29] is the requirement for a separate reference wave, which results in
a phase stability decrease and the demand for a precise adjustment of the intensity ratio
between object and reference waves. To overcome these problems, several approaches were
reported [17,30 34] . Here, in order to avoid a separately generated reference wave, a
Michelson interferometer approach for DHM is presented [35] .

Figure 6.2 shows a sketch of the Michelson interferometer-based DHM arrangement setup
which can be attached to an inverted research microscope [35] . In analogy to the setup in

WS

BS1

SM

CL

S

MO

α

BS2

PC

M2

M1

Figure 6.2
Schematic of an experimental setup for Michelson interferometer-based self-interference DHM.
WS: white light source; BS1, BS2: beam splitter cubes; CL: condenser lens; SM: single-mode fiber;
S: sample (here, Petri dish with adherent cells); MO: microscope lens; M1, M2: mirrors; CCD:
charge-coupled device sensor; α : tilt angle; PC: computer [36] .