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Bio-Inspir ed Fluidic Lenses for Imaging and Integrated Optics 219

FIGURE 9-14 ZEMAX Geometric Bitmap Image Analysis on the images produced from the
improved design in Fig. 2.2.8. (a) Zoom-in image. (b) Zoom-out image, corresponding to
Fig. 2.2.8 (b). In both cases, image quality is superior to that in Fig. 2.2.7.

zoom-out images. The analysis result is shown in Fig. 9-14. Compar-
ing Figs. 9-12 and 9-14, we demonstrate that the quality has been
greatly improved.

9-2-4 Summary
Fluidic lens brings new opportunities to optical imaging systems.
By integrating a fluidic lens with fixed lenses, compact universal
imagers with camera and microscope functions can be formed.
Furthermore, with fluidic lenses, optical zoom without moving lenses
is demonstrated.

9-3 Bio-Inspired Intraocular Lens—Restoration
of Human Vision
As discussed previously, in a constrained space, bio-inspired fluidic
lens can achieve much greater accommodation than solid lenses.
Since fluidic lenses are inspired by animal vision, it is natural to apply
the devices to restore (or enhance) human vision. In this section we
report the preliminary investigation of the feasibility of using fluidic
lenses to replace the crystalline intraocular lenses (IOLs) [53]. Because
of the inherent difficulty in quantitative assessment of the performance
of fluidic lenses for human vision, we have set up a scaled-up eye
model using a CMOS sensor to simulate the retina near the fovea.
A crystalline lens in human eye is a transparent, lentil-shaped
tunable lens. The lens not only provides one-third of the eye’s total
power, but also changes the focal length of an eye continuously from
the change of the surface curvature. Accommodation, which is the
ability to focus far and near, is made possible by the crystalline lens.
For patients with cataract disease, a crystalline lens becomes cloudy
and finally obstructs the transmission of light. The most effective and