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 range (10nm bandwidth) > 50 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 330FIB50 330 10 25 £265.00 337FIB50 337.1 10 25 £265.00 340FIB50 340 10 25 £265.00 350FIB50 350 10 25 £245.00 355FIB50 355 10 25 £245.00 360FIB50 360 10 25 £245.00 365FIB50 365 10 25 £245.00 370FIB50 370 10 25 £245.00 380FIB50 380 10 30 £245.00 390FIB50 390 10 37 £245.00 400FIB50 400 10 37 £185.00 410FIB50 410 10 40 £185.00 420FIB50 420 10 45 £185.00 430FIB50 430 10 45 £185.00 436FIB50 435.8 10 45 £185.00 440FIB50 440 10 45 £185.00 450FIB50 450 10 45 £185.00 458FIB50 457.9 10 45 £177.40 470FIB50 470 10 45 £177.40 480FIB50 480 10 45 £177.40 488FIJ50 488 10 75 £300.00 490FIB50 490 10 45 £177.40 500FIB50 500 10 50 £177.40 510FIB50 510 10 50 £177.40 515FIJ50 514.5 10 75 £300.00 520FIB50 520 10 50 £177.40 530FIB50 530 10 50 £177.40 532FIJ50 532 10 75 £315.00 540FIB50 540 10 50 £154.80 546FIB50 546.1 10 50 £154.80 550FIB50 550 10 50 £154.80 560FIB50 560 10 50 £154.80 570FIB50 570 10 50 £154.80 580FIB50 580 10 50 £177.40 590FIB50 590 10 50 £154.80 600FIB50 600 10 50 £154.80 610FIB50 610 10 50 £154.80 620FIB50 620 10 50 £154.80 630FIB50 630 10 50 £154.80 633FIJ50 632.8 10 75 £315.00 636FIB50 636 10 50 £177.40 640FIB50 640 10 50 £154.80 650FIB50 650 10 50 £154.80 656FIB50 656.3 10 50 £154.80 660FIB50 660 10 50 £154.80 670FIJ50 670 10 75 £315.00 680FIB50 680 10 50 £215.00 685FIJ50 685 10 75 £315.00 690FIB50 690 10 50 £154.80 700FIB50 700 10 50 £154.80 810FIB50 810 10 45 £195.00 1064FIB50 1064 10 70 £271.40 Knight Optical > Filters > Interference band-pass filters > Standard range (10nm bandwidth) > 50 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.