Filters When it comes to studying the Auroras, Airglow, and other low-light-level penomena, we know that every single photon counts. Good optical lens design is an art as much as it is a science. We draw on our long experience and in-depth knowledge of the properties of light and materials to develop state-of-the-art optical systems. Our expertise extends beyond the visible spectrum to the ultraviolet and infrared. To meet your design needs, we use ZEMAX OpticStudio for optical modeling and SolidWorks for opto-mechanical engineering. Please feel free to contact us for your optical design needs.

In addition to such professional consulting services (and helpful advice, which is always gratis), we offer the items listed below. We research and stock a number of high quality, high efficiency components that can bring enhanced capabilities to your existing Keo instrument and to instruments that you are currently building in-house. If you do not see what you need here, send us an email and we shall do our best to directly assist you — or at least point you in the right direction. We always recommend Surplus Shed, which can be a good source of some hard-to-find items, or when on a shoestring budget. For quick turnaround CNC machining of prototype, low-volume parts, it's hard to beat the good folks over at Proto Labs.

We have been known to lend out instruments, such as for experimental campaigns, and to donate lenses & other bits and pieces to various projects, including student assignments. We also contribute prizes for university student competitions.

At the risk of sounding self-righteous, we believe that science funding cuts should not be allowed to stifle the motivation of bright young people who engage in basic scientific research. Their endeavours increase our understanding of the geospace environment within which humankind lives and has its being, and contribute to technological innovation.

Please consider subscribing to our blog, through which we aim to keep you up to date on our most recent products and innovations. If you have recent scientific publications based on optical data from a Keo instrument, please let us know so that we may feature the bibliographic references in an upcoming blog entry. Photos from your latest fixed or portable field installation of optical instruments (whether Keo instruments or not) would also be appreciated, as they might provide inspiration for other research groups. We also aim to provide helpful advice for those building their own instruments in-house.



We stock a wide range of custom manufactured imaging-quality narrow-band interference filters (0.8 nm to 10 nm FWHM, as well as notched wideband OH filters) targeted at auroral and airglow work (imagers, photometers, and FPIs).

Filters are custom manufactured to Keo Scientific's discerning specifications as to cosmetics, in-band transmission (typically 65–80% or better, depending on wavelength), and out-of-band blocking (typically OD5–OD9). When it comes to Auroral and Airglow work, you will not find better suited stocked filters anywhere.

Some of our more popular stocked filters are 2, 3 and 4 inch diameter 427.8 nm, 557.7 nm, 589.3, 630.0 nm, 777.4 nm, 865.0 nm, wideband with notch at 865 nm, and a selection of appropriate "background channel" filters. As for non-interference filters, we stock various diameters of BG3 glass, Wratten 89B, and others. Custom filters are available upon request.

For stocked filters, we can typically offer a better price than what the manufacturer would be able to offer for a Qty 1 order. Some more information may be found in this brochure.



For your home-brew projects, Keo Scientific can provide a variety of hard to find compound lenses, such as Rodenstock, Delft, and Kowa lenses of F0.7–F1.0. As well, we can supply you with custom-ground and coated doublet achromat lenses, 75–100+ mm diameter (100–1000 mm EFL), and plano convex 75–200 mm diameter lenses (150–1000 mm EFL), at a quality equal to or better than that available from more traditional optics outlets, and at lower cost.

We currently (mid 2015) have a large collection of Mamiya and Canon fisheye (all sky) lenses and about 20 pieces of the (much sought-after) Canon 50mm F0.95 Rangefinder lens in stock.