Living Image 3.1

F. Fluorescent Imaging
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combination provides high emission throughout the 400-950 nm wavelength range
(Figure F.2). The dichroic reflector reduces infrared coupling (>700 nm) to prevent
overheating of the fiber-optic bundles, but allows sufficient infrared light throughput to
enable imaging at these wavelengths. The Living Image software controls the illumination
intensity level (off, low, or high). The illumination intensity at the low setting is
approximately 18% that of the high setting.
Figure F.2 Relative spectral radiance output for the quartz halogen lamp with dichroic reflector.
The lamp output is delivered to the excitation filter wheel assembly located at the back of
the IVIS ® Imaging System (Figure F.3). Light from the input fiber-optic bundle passes
through a collimating lens followed by a 25 mm diameter excitation filter. The IVIS
Imaging System provides a 12-position excitation filter wheel, allowing you to select from
up to 11 fluorescent filters (five filters on older systems). A light block is provided in one
filter slot for use during bioluminescent imaging to prevent external light from entering
the imaging chamber. The Living Image software manages the motor control of the
excitation filter wheel.
Figure F.3 Excitation filter wheel cross section.
Following the excitation filter, a second lens focuses light into a 0.25 inch fused silica
fiber-optic bundle inside the imaging chamber. Fused silica fibers (core and clad), unlike
ordinary glass fibers, prevent the generation of autofluorescence.
The fused silica fiber bundle splits into four separate bundles that deliver filtered light to
four reflectors in the ceiling of the imaging chamber (Figure F.1). The reflectors provide a