Interference band-pass filters These Interference Band pass Filters are used to isolate and transmit a narrow wavelength that is required and block all other wavelengths through reflection. This range of Interference Band pass Filters consist of an all-dielectric coating along with other coatings for additional blocking and cemented together to form a stack. The individual filters are mounted in nested rings, providing a labyrinth epoxy edge seal for greatly extended life. Although these are mounted, unmounted type can be supplied at special request. These Interference Band pass Filters are all typically 3-7 cavity. Uses include line selection, laser signal selection, colorimetry and fluorimetry. They can also be used for imaging. When using high powers the reflective side must be towards the incoming light.
Knight Optical > Filters > Interference band-pass filters > Standard IR range (10-18nm bandwidth) > 25 diameter (mm) Only UK and EU customers are charged VAT at 17.5%, customers outside the EU and EU customers based outside the UK who have a valid EU VAT number will not be charged VAT Bulk Discounts! Where (B) appears next to a price below, bulk prices are available, click the (B) button to view! PDF Part No. Wavelength (CWL nm) Bandwidth (HBW nm) Peak transmission (%) Price Qty Buy 720FIB25 720 10 50 £51.00 730FIB25 730 10 50 £51.00 740FIB25 740 10 50 £51.00 750FIB25 750 10 50 £51.00 760FIB25 760 10 50 £51.00 770FIB25 770 10 50 £51.00 780FIB25 780 10 50 £51.00 790FIB25 790 10 50 £51.00 800FIB25 800 10 50 £51.00 810FIB25 810 10 45 £51.00 820FIB25 820 10 45 £51.00 830FIB25 830 10 45 £52.00 840FIB25 840 10 45 £52.00 850FIB25 850 10 45 £52.00 860FIB25 860 10 45 £53.00 870FIB25 870 10 45 £53.00 880FIB25 880 10 45 £53.00 890FIB25 890 10 45 £53.00 900FIB25 900 10 45 £53.00 905FIB25 905 10 50 £53.00 910FIB25 910 10 50 £53.00 920FIB25 920 10 50 £53.00 930FIB25 930 10 50 £53.00 940FIB25 940 10 50 £53.00 950FIB25 950 10 50 £53.00 960FIB25 960 10 50 £53.00 970FIB25 970 10 50 £53.00 980FIB25 980 10 50 £53.00 990FIB25 990 10 50 £53.00 1000FIB25 1000 15 50 £53.00 1020FIB25 1020 15 50 £53.00 1040FIB25 1040 15 50 £53.00 1050FIB25 1050 15 47 £53.00 1064FIB25 1064 16 50 £53.00 1064FIJ25 1064 10 75 £67.00 1080FIB25 1080 15 45 £53.00 1100FIB25 1100 16.5 45 £56.50 1120FIB25 1120 17.5 45 £56.50 1140FIB25 1140 17.5 45 £56.50 1160FIB25 1160 18 45 £56.50 1180FIB25 1180 11 45 £56.50 1200FIB25 1200 11 45 £56.50 1220FIB25 1220 11 45 £56.50 1240FIB25 1240 11.5 45 £56.50 1260FIB25 1260 12 45 £56.50 1280FIB25 1280 12 45 £56.50 1300FIB25 1300 12 45 £56.50 1320FIB25 1320 12.5 45 £56.50 1340FIB25 1340 13 45 £56.50 1360FIB25 1360 13 45 £56.50 1380FIB25 1380 13.5 45 £56.50 1400FIB25 1400 14 40 £57.50 1420FIB25 1420 14 40 £57.50 1440FIB25 1440 14 40 £57.50 1460FIB25 1460 14 40 £57.50 1480FIB25 1480 15 40 £57.50 1500FIB25 1500 15 40 £59.50 1520FIB25 1520 15 40 £59.50 1540FIB25 1540 15 40 £59.50 1560FIB25 1560 15 40 £59.50 1580FIB25 1580 16 40 £59.50 1600FIB25 1600 13 40 £59.50 1620FIB25 1620 13 40 £59.50 1640FIB25 1640 16 40 £59.50 1660FIB25 1660 13 40 £59.50 1680FIB25 1680 14 40 £59.50 1700FIB25 1700 15 40 £59.50 1720FIB25 1720 15 40 £63.50 1800FIB25 1800 16 40 £59.50 1900FIB25 1900 16 35 £59.50 2000FIB25 2000 17 35 £59.50 Knight Optical > Filters > Interference band-pass filters > Standard IR range (10-18nm bandwidth) > 25 diameter (mm)
Dimensions   Diameter: +0,-0.3mm Thickness: 5-6mm Clear aperture:   12.5mm dia. 8.6mm 25mm dia. 19mm 50mm dia. 44mm   Specification
Range Fin FIB (<1100nm) FIB (=1100nm) FIJ FIR FIW CWL tolerance (nm) +0.7,-0.4 ±2 ±3 ±2 ±5 ±7 HBW tolerance (nm) +0.7 ±2 ±3 ±2 ±5 ±8 Bandwidth ratios*             10%BW/HBW 1.74 1.35 1.74 1.35 1.13 1.05 1%BW/HBW 3.21 1.99 3.21 1.99 1.30 1.18 0.1%BW/HBW 6.09 2.92 6.09 2.92 1.60 1.36 0.01%BW/HBW 12.68 4.41 12.68 4.41 2.04 1.69 Blocking type and specification Induced transmittance filter10?? absolute, 200-3500+ Dielectric stacks:10?? ave,10?³ abs, x-ray to 1150nm No of cavities (min) 2 3 2 3 5 7
Interference filter glossary Bandwidth (HBW, FWHM): Width of the passband; specifically, the difference between the two wavelengths at which the transmittance is half the peak value. Similarly, 10% bandwidth (10%BW) is measured between points where T=10% of peak, etc. Blocking: Rejection of any energy outside the passband. Absolute blocking is the transmittance level not exceeded at any point in the specified wavelength range. Average blocking is a value averaged over a range. Cavity: The basic element from which a filter is constructed, consisting of two reflective coating stacks with a spacer layer in between. Our standard range is based on a series of three cavities and therefore a squarer shape of passband. Centre wavelength (CWL): The wavelength midway between the half-power points which define bandwidth (se above) Transmittance (T): The guaranteed minimum value of peak transmittance of the filter (not necessarily occurring at the centre wavelength) Technical Notes To estimate the transmittance near the passband, use the bandwidth ratios given in "specifications" e.g. 340FIB12 has HBW-10; for FIB range 1%BW/HBW=1.99,so 1%BW-19.9; .e transmittance ill be 1% of pea (about 0.3% absolute) at 340nm ±(19.9/2), i.e. about 30nm and 350nm. For light incident at an angle the centre wavelength ?o (1-k sin²?) where k is approximately 0.24 for FIW filters and 0.11 for all others. The CWL shifts towards the longer wavelengths with increasing temperature at about 0.1nm/K.