Filters and mounts
177
Goldeye G/CL Technical Manual V4.2.0
Peak Transmittance
Also referred to as filter
Transmission Rate
. The peak transmittance describes the
maximum amount of light that a filter allows to pass. No filter allows 100 percent
of the light to pass, however, good quality filters allow more light to pass through,
thus their transmission rate is closer to 100 percent. Filters of lower quality appear
darker, they transmit only slightly more than 50 percent of the light.
Tolerance
The range of wavelengths within the passband, equally on both sides of the central
wavelength, that provide transmission rates very close to the peak transmittance
around the center wave length.
FWHM (Full Width at Half Maximum)
Also called
Half Bandwidth
. Defines the width of the passband of a bandpass filter.
It is defined as the range of wavelengths on either side of the CWL where the
transmission rate is one half of the peak transmittance or higher.
Figure 50: Detail of the water filter pictured in
,
CWL = 1450 nm
±7 nm, FWHM = 26.5 nm
