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Astronomical Filter

Asahi Spectra has supplied astronomical filters to world famous observatories,
institutes or universities over 10 years.
Unlike cheap astronomical filters for the amateurs, Asahi astronomical filters are
definetely manufactured for professional astronomers to meet rigid specifications
and environmental durability.
New discovery and progress of science shall be emerged by Asahi filters.
Asahi astronomical filters are actually installed on telescopes in Hawaii, Chile,
Canary, Arizona, South Africa, Australia or other important observatories.

Asahi filters has been supplied a installed to...


Advantage of Asahi Astronomical Filters
  • Optimized interference film design in consideration of convergent beam.(e.g. F/1.5)
  • This shall be the great advantage for narrow bandpass in NIR wavelength.
  • Approximate 300 x 300mm with coating uniformity over the clear aperture
  • Image quality
  • High transmission in particular UV wavelength
  • Actual transmission data by text file available

We always wish to cooperate with professional astronomers and contribute to the progress of science. Contact us if you are interest in our custom-made filters.

1. SDSS Filters (u',g',r', i',z'-band)


SDSS Filters (u',g',r', i',z'-band)
Notice:

Due to the serious quality problem in colored glass, it is probable
to use another glass instead of the original prescription.

SDSS(Sloan Digital Sky Survey) photometric systems are currently the most common, important and unignorable in astronomy.
We proudly supplied Apache Point Observatory with SDSS filters, where they are used as the original SDSS photometric systems.

We know the specifications SDSS project specified, and strictly observe them.We promise that we will supply genuine SDSS filters which completely meet the original specifications for you.

2. Johnson / Bessel Filters (U,B,V,R,I)


Conventional Johnson / Bessel Filters
Conventional Johnson / Bessel Filters
Notice:





Due to the discontinuing of GG385 and BG12 by Schott AG, we have to currently make B filter by using alternative glasses.


New Johnson / Bessel Filters (Interference film combination)
New Johnson / Bessel Filters (Interference film combination)

Though more basic and rather classical photometric system, Johnson / Bessel filters are still important for astronomers.
We can supply not only typical Johnson / Bessel filters made by only colored glasses, but also the filters with interference film coombination.


3.

Narrow Bandpass Filters / Stroemgren u, v, b, y, H-alpha, H-beta, HeII, OIII, SII, Red continuum, etc.

Narrow Bandpass Filters / Stroemgren u, v, b, y, H-alpha, H-beta, HeII, OIII, SII, Red continuum, etc.

Astronomical filter is sometimes installed in the fast optical system.
As you know, the spectral response depends on angle of incidence in interference filter. Especially in narrow bandpass, the influence of convergent beam must be considered to keep ideal center wavelength or high transmittance. We have developed the optimized thin-film design method, by which you will be able to obtain the best performance of filter.

4. Pan-STARRS Filter (g, r, i, z, y)


Pan-STARRS Filter (g, r, i, z, y)

Pan-STARRS -- the Panoramic Survey Telescope & Rapid Response System -- is an innovative design for a wide-field imaging facility being developed at the University of Hawaii's Institute for Astronomy. The University of Hawaii has set up an international consortium in the Pan-STAARS Telescope No.1 comprised of astronomers from Germany, the USA, the United Kingdom and Taiwan to operate and analyze the data from the telescope. Pan-STARRS photometric filters must be getting important in the future.

5. Astronomical Near-Infrared Filter (Z, Y, J, H, K)


Astronomical Near-Infrared Filter (Z, Y, J, H, K)

Asahi is currently challenging to develop some important NIR filters for astronomers such as WFCAM/VISTA.

6. Astronomical Dichroic Mirror


AOI 45 degrees

Astronomical Dichroic Mirror

These days dichroic mirror is getting important to observe the multiple colors simultaneously, especially in GRB observation.
Asahi dichroic mirror can meet "steep edge", "high reflectance with wide range" "high transmittance with wide range" all together, even if the angle of incidence is 45 degrees and the polarization occurs.

7. Large Filter for Large Wide-Field Telescope


We are launching to develop large filter, which will be quite important for wide-field observatories (HSC, LSST, DEC, Pan-STARRS or WIYN) in the future.

We can produce filters as large as 300x300mm at this moment. By using our propriety technique, the variation of center wavelength, cut-on or cut-off wavelength can be minimized.


Measuring Point


 

   Filter Size : 300 x 300mm
   Variation at 350nm : Approximate 1nm*
   *It depends on the target wavelength

 

   For Astronomical Filter inquiries:
   Overseas Sales Manager, Toshihiko Kimura
   Contact Form: Click here for our contact form

Standard Filters

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