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) > 12.5 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 720FIB12 720 10 50 £22.50 730FIB12 730 10 50 £22.50 740FIB12 740 10 50 £22.50 750FIB12 750 10 50 £22.50 760FIB12 760 10 50 £22.50 770FIB12 770 10 50 £22.50 780FIB12 780 10 50 £22.50 780FIJ12 780 10 75 £40.70 790FIB12 790 10 50 £22.50 800FIB12 800 10 50 £22.50 810FIB12 810 10 45 £22.50 820FIB12 820 10 45 £22.50 820FIJ12 820 10 75 £40.70 830FIB12 830 10 45 £22.50 830FIJ12 830 10 75 £40.70 840FIB12 840 10 45 £22.50 850FIB12 850 10 45 £24.85 860FIB12 860 10 45 £24.85 870FIB12 870 10 45 £24.85 880FIB12 880 10 45 £24.85 890FIB12 890 10 45 £24.85 900FIB12 900 10 45 £24.85 900FIJ12 900 10 75 £40.70 905FIB12 905 10 50 £24.85 910FIB12 910 10 50 £24.85 920FIB12 920 10 50 £24.85 930FIB12 930 10 50 £24.85 940FIB12 940 10 50 £24.85 950FIB12 950 10 50 £24.85 960FIB12 960 10 50 £24.85 970FIB12 970 10 50 £24.85 980FIB12 980 10 50 £24.85 990FIB12 990 10 50 £24.85 1000FIB12 1000 15 50 £24.85 1020FIB12 1020 15 50 £24.85 1040FIB12 1040 15 50 £24.85 1050FIB12 1050 15 47 £24.85 1064FIB12 1064 16 50 £24.85 1064FIJ12 1064 10 75 £40.70 1080FIB12 1080 15 45 £24.90 1100FIB12 1100 16.5 45 £26.85 1120FIB12 1120 17.5 45 £26.85 1140FIB12 1140 17.5 45 £26.85 1160FIB12 1160 18 45 £26.85 1180FIB12 1180 11 45 £26.85 1200FIB12 1200 11 45 £26.85 1220FIB12 1220 11 45 £26.85 1240FIB12 1240 11.5 45 £26.85 1260FIB12 1260 12 45 £26.85 1280FIB12 1280 12 45 £26.85 1300FIB12 1300 12 45 £26.85 1320FIB12 1320 12.5 45 £26.85 1340FIB12 1340 13 45 £26.85 1360FIB12 1360 13 45 £26.85 1380FIB12 1380 13.5 45 £29.45 1400FIB12 1400 14 40 £29.45 1420FIB12 1420 14 40 £29.45 1440FIB12 1440 14 40 £29.45 1460FIB12 1460 14 40 £29.45 1480FIB12 1480 15 40 £29.45 1500FIB12 1500 15 40 £32.00 1520FIB12 1520 15 40 £32.00 1540FIB12 1540 15 40 £32.00 1560FIB12 1560 15 40 £32.00 1580FIB12 1580 16 40 £32.00 1600FIB12 1600 13 40 £32.00 1620FIB12 1620 13 40 £32.00 1640FIB12 1640 16 40 £32.00 1660FIB12 1660 14 40 £32.00 1680FIB12 1680 14 40 £32.00 1700FIB12 1700 15 40 £32.00 1720FIB12 1720 15 40 £32.00 1800FIB12 1800 16 40 £32.00 1900FIB12 1900 16 35 £32.00 2000FIB12 2000 17 35 £32.00 Knight Optical > Filters > Interference band-pass filters > Standard IR range (10-18nm bandwidth) > 12.5 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.