Interference filters in general
Interference filters are optical elements built from thin coatings that select light by wavelength. A coating stack creates transmission in wanted bands and rejection outside them, which is why the same manufacturing idea produces many different products: narrow band pass filters, fluorescence filters, high reflection filters, beam splitting filters, color splitting filters, IR sensor filters, short pass filters, and neutral density filters all belong to this family in the company's listed production lines. The interference filters overview maps the family, and the optical filter types guide lists the types in one place.
Selection factors, as inquiry items
The selection factors buyers usually work through are centre wavelength, bandwidth, cut-off depth, size, and substrate material. On this site those factors appear as inquiry confirmation items, not as values, except where a product page documents values. Centre wavelength is the centre of the band you need to pass or the edge you need to cut. Bandwidth is the width of the band you need to pass. Cut-off depth is how completely light outside the wanted band must be rejected. Size is the physical size and shape the element must fit. Substrate material is the base material the coating sits on, where it matters for the application. Naming those five items, with the wavelength region they apply to, turns a vague request into a checkable requirement.
Reading the illustration on this page
The illustration on this page is a transmission spectrum curve illustration. It shows the general form of a transmission curve, with transmission on one axis and wavelength on the other. It is not a specification for any product on this site, and it does not state a value for any line. It is included so that buyers can recognise the form of curve that is usually discussed when a filter requirement is described: a pass region, a transition, and a blocked region.
Where documented values do exist
Documented values on this site exist for two lines only. Fluorescence filters document IAD hard coating, five excitation and emission examples, blocking figures, a slope figure, dye and probe names, and sizes, on the fluorescence filters page. Neutral density filters document a wavelength range of 200 to 1000 nm, an ND value range of ND 0.1 to 4, and customized sizes, on the neutral density filters page. Blocking figures from the fluorescence page must not be read as general interference filter specifications, and this guide does not repeat them as such. For every other line, selection factors remain inquiry items, and buyers should ask for confirmation.
From guide to inquiry
Use this guide to name your requirement, then use the line page for the product you need to check its inquiry list, then send the requirement through the inquiry page. Please confirm centre wavelength, bandwidth, cut-off depth, size, and substrate material in your inquiry before ordering, together with the quantity basis and delivery basis.