Holography has widespread influence in many areas of technology, from
metrology and biomedical imaging
to fine arts and entertainment. But
holography’s coherent light requirement
presents a serious constraint for a wider
range of applications. 1 With coherent
laser illumination, holographic 3-D
imaging would not be as easy and
mundane as basic photography.
Many researchers have tried to
record holograms under incoherent
illumination, but most of their methods have limited degrees of practicality. However, a recent development
called Fresnel incoherent correlation
holography (FINCH) shows promise.
FINCH is based on self-interference
between two copies of a spherical
wave from each source point, using a
spatial light modulator as a combination of curved and flat mirrors. 2 I
proposed an incoherent holography
scheme for adaptive optics called
self-interference incoherent digital
holography (SIDH). SIDH measures
and compensates for aberrations
using only holographic processes—
removing the need for wavefront
sensors or deformable mirrors. 3, 4 The
technique is being developed for
potential applications in astronomical
and ophthalmic imaging.
SIDH is based on a modified
Michelson interferometer with two
mirrors of different curvatures
and can be used to generate full-color 3-D images of naturally lit
outdoor scenes. 5 First, a color CCD
camera acquires the interferograms.
Next, the three color channels are
separated and analyzed individually
to obtain the red, green and blue
component holograms. The resultant
amplitude images are then combined
to produce 3-D full-color holographic
images of daylight-illuminated
outdoor scenes. The 3-D content of the
holographic image is demonstrated
by numerically focusing to differ-
ent distances. This may be the first
recording of outdoor scenes under
daylight illumination using a holo-
Incoherent digital holography
techniques like SIDH open up a
wide range of new applications and
capabilities for holography because
they remove the serious constraint
of coherent lasers as illumination
sources. One can expect applications in all areas of imaging such
as astronomy, remote sensing and
fluorescence imaging, as well as in
non-optical wavelengths such as
Two frames from the movie show a close toy boat (a) and distant buildings (b) focused
with the self-interference incoherent digital holography scheme.
Myung K. Kim
University of South Florida,
Tampa, Fla., U.S.A.
1. M.K. Kim, Digital Holographic
Techniques, and Applications,
2. J. Rosen and G. Brooker.
fluorescence three-dimensional holographic
microscopy,” Nat. Photonics
2, 190 (2008).
3. M.K. Kim. “Adaptive optics
by incoherent digital holography,” Opt. Lett. 37, 2694
4. M.K. Kim. “Incoherent digital
holographic adaptive optics,”
Appl. Opt. 52, A117 (2013).
5. M.K. Kim. “Full color natural
light holographic camera,”
Opt. Express 21, 9636 (2013).
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the video that accompanies this article.
Holographic Camera Uses
Full-Color Natural Light