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http://machinevision.navitar.com
• email: [email protected]
Zoom 6000 High Mag Zoom Lenses
Zoom 6000
NIR Lens
System
Navitar’s Zoom 6000 NIR lens
system offers high resolution and
unparalleled sensitivity for capturing
microscopic images. We have
specially coated the glass on our
Zoom 6000 NIR lens systems to be
optimized for imaging in the 700-
1550nm (0.7-1.5 microns) wave-
length range. Our Zoom 6000 NIR
lens system is easy to configure and
set up. Simply find the field of view
and working distance required just
as you would with any of our other
standard 6X lenses.
For a complete listing of available
Zoom 6000 NIR parts, please
reference our website or contact
your Navitar sales representative.
Body tubes with detents, aperatures
or motorized are available by
custom order.
Applications Where NIR
Optics are Useful
• Wafer characterization.
• Laser beam profiling.
• Optical component
measurement and analysis.
•
Fiber alignment and
inspection.
•
Assembly and monitoring.
A list of all 6X NIR Zoom system components can be found on our website at
www.machinevision.navitar.com
About Using NIR Lenses
The wavelength band just beyond the visible is known as Near Infrared (NIR).
NIR is the electromagnetic band of wavelengths between 0.7-1.5 microns
(700-1550nm). When light strikes a glass surface, a portion is bounced back,
thereby reducing the strength of the transmitted image. Apply this behavior
to a zoom lens with many glass surfaces, and the result is a severe reduction
in image intensity. To counteract the loss, the lenses are coated with materials
that minimize this effect.
Note:
Since NIR lenses are not operating within the visible spectrum, the
resulting image is slightly different than when using a standard 6X system.
The standard lens resolution limits of an NIR lens are based on an assumed
average wavelength of 0.5 microns and is inversely proportional to wavelength
(maximum MTF = 3000xNA in the visible wavelength). Therefore, substituting a
wavelength of 1.5 microns will reduce the maximum resolution by a factor of 3.
In practice, this means a slight reduction of contrast at the higher wavelengths.
Lens focal lengths shift slightly with wavelength, which impacts the Numerical
Aperture (NA), which affects the depth of field (.0005/NA^2). Generally, the NA
is reduced, which produces a greater depth of field, along with a reduction in
maximum resolution. Standard NIR microscope objectives are usually lower in
NA, also reducing maximum resolution values.
