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optolong Fluorescence Filter

Optical fluorescence filters(fluorescent light filters) are the essential optical components for most of the biotech instrument and analytical instrument. Most of the fluorescence imaging system consists of three kinds filters: exciter( or exitation filters), emitter (or emission filters) and dichroic filter(or dichroic mirror) to work properly.

Exitation filter is usually a shortpass filter or bandpass filter which transmit the wanted wavelength absorbed by fluorophore. Emission filter is a bandpss filter or longpass filter which transmit the emission wavelength of fluorophore. Dichroic filter is placed with 45 degrees to reflect exitation and transmit emission to detector.

For the reason of different application, some system may not need them all. One exciter, one emitter placed with a special angle of incidence and no dichroic mirror needed is the most common.

Fluorescence filters are highly applied in life science instrument and biomedical imaging system like fluorescence microscop, PCR analyzer, microplate reader, raman microscopy, cell counters, flow cytometry, fluorometer, surgical devices and other system which needs high content analysis imaging.

High quality biotech instrument imaging requirement:

  • High transmission to ensure the brightness of fluorophore.
  • Dark background to enhance contrast of final image.
  • Deep blocking depth for the overlap of exciter and emitter. 
  • Elimate auto fluorescence of interest fluorophore and all the other scattering light.
  • High signal tense.

Optolong is a professional fluorescence filters manufactures who is dedicated on single band filter set, individual filters and multiband filter sets.

Coating Art(OEM Capability):

  • Multi cavity deposition makes thin film layers to be more than 300.
  • Durable hard coating film layers.
  • More than OD7 blocking depth on one single substrate.
  • Transmission above 90%.
  • Bandwidth narrow to 3nm.
  • Unique design to control rectangularity, overlap.
  • Wide angle of incidence change.

Two system of ION assisted coating:
According to client’s budget ,OPTOLONG support two different coating system for client.

  • Fluorescence filters with single substrate coating. 1.0mm thickness exciter and emitter. One single substrate to ensure OD7 blocking depth, transmission above 90% and extremely durable at the same time.
  • Fluorescence filters with two pcs or more substrate glue. Thickness to 2.0-3.5mm.
  • The purpose of two or more pcs substrate glue together is to ensure as high blocking depth and spectrum performance as possible. Mounted with Black anodized ring would last life time of filter. Skilled workers with more than 10 years experience would minimize the effect of glue to spectrum.

Material selection:
To minimize auto fluorescence of aimed fluorophores, we choose:

  • Fused silica 
  • Scott B270 to minimum auto fluorescence.
  • High quality flatness and pluralism selection to minimum pixel shift and color cast of image.