THORLABS KURIOS-VB1, Руководство пользователя

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Kurios
®
Liquid Crystal Tunable Filters Chapter 6: Technical Terminology
Page 26
CTN002811-D03
6.7. Tuning Accuracy
The difference between the wavelength setting and the actual filter output center wavelength is defined as tuning
accuracy, and is measured in terms of FWHM at the current set wavelength. KURIOS tunable filter output center
wavelength accuracy is corrected to within ±FWHM/10. Tuning Accuracy or wavelength error can be wavelength
dependent.
6.8. Wavelength Uniformity
Uniformity is defined as the maximum center wavelength shift within the clear aperture in terms of the FWHM
bandwidth at the specified wavelength setting. This is measured with a small broadband incident beam through the
filter to obtain the filter output center wavelength. The incident beam is then scanned across the entire clear aperture
of the filter while the output wavelength at each point is recorded. The wavelength shift at each point is then
calculated.
6.9. Angle of Incidence (Field of View)
Field-of-view (FOV) is defined as the maximum angle of off-axis rays propagating through the filter while the center
wavelength shift is within ±FWHM/2 from the set wavelength. For KURIOS visible wavelength filters (-WB1, -VB1,
XL1 and -WL1), the AOI at 550 nm is measured as reference. For the KURIOS near-IR filter (-XE2), the AOI at
850 nm is measured as reference.
Figure 23 Illustration of Center Wavelength Shift with Off-Axis Rays Propagating through the Filter
Each KURIOS tunable filter comes with a test report including plots of the spectrum, FWHM, transmission, tuning
accuracy, and switching time.