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Dark Energy Camera (DECam) 620mm diameter Halpha filter

figure DECam 620mm Halpha filter

Asahi has provided 7 kinds of 620mm broad band filters, u, g, r, i, z, y, and VR filters to the DECam at CTIO in 2011 ~ 2014.

We provided the Halpha filter, the second narrow band filter for the DECam in 2017.
It was ordered by Prof. Eric Peng at KIAA and Prof. Thomas Puzia at PUC.
The uniformity of coating was excellent, 0.16% of the center wavelength over the large clear aperture, 600mm diameter.

One Degree Imager (ODI) 445mm x 428mm NB422 filter

figure ODI 445mm x 428mm NB422 filter

Asahi has provided the ODI 445mm x 428mm u band, the hardest broad band filter to WIYN Observatory in 2015.

We provided the ODI NB422 filter, the second narrow band filter for the ODI in 2017.
It was ordered by Prof. Kyoung-Soo Lee at Purdue University.
The uniformity of coating was phenomenal, 0.094% of the center wavelength (less than 0.1%!!), world record of
the uniformity in the past astronomical large filters produced ever.

Zwicky Transient Facility (ZTF) 491mm x 448mm i-band filter

figure ZTF 491mm x 448mm i-band filter

The Zwicky Transient Facility (ZTF) is a new time-domain survey that had first light at Palomar Observatory in 2017.
The size of the ZTF filter is 491mm x 448mm, the second largest ever produced in the world.

Asahi provided the ZTF i-band filter to Caltech Optical Observatories in 2018.
The uniformity of coating was perferct, 0.11% of both cut-on and off wavelengths over the large clear aperture.

Our experience to provide large filters during the last 10 years

ZTF 491mm x 448mm i-band filter (delivered in 2018)
ODI 445mm x 428mm NB659 and NB746 filters (will be delivered by August 2018)
ODI 445mm x 428mm NB422 filter (delivered in 2017)
ODI 445mm x 428mm u' band filter (delivered in 2015)
DECam 620mm diameter Halpha filter (delivered in 2017)
DECam 620mm diameter VR filter (delivered in 2014)
DECam 620mm diameter u filter (delivered in 2012)
DES 620mm diameter g, r, i, z, y filters (delivered in 2011-2012)
HSC 600mm diameter r-band filter (delivered in 2016)
HSC 600mm diameter g', z', Y filters (delivered in 2012)
PFS 390mm x 365mm red dichroic mirror, total 4 pcs (delivered in 2015-2018)
MegaCam / CFHT 350mm x 300mm u filter (delivered in 2014)
KMTNet 310mm x 310mm B, V, R, I, g', r', i', z' filters, total 16 pcs (delivered in 2012)
OGLE 310mm x 310mm V, I filters (delivered in 2009)
Megacam / Magellan 300mm x 300mm g+r filter (delivered in 2013)
Binospec 292mm x 209mm g, r, i, z filters, total 8 pcs (delivered in 2013)
Binospec 292mm x 209mm long pass filter, total 2 pcs (delivered in 2014)
SALT HRS 350mm x 40mm dichroic mirror (delivered in 2010)
PTF 250mm x 165mm redshifted Halpha filters, total 4 pcs (delivered in 2011, 2014)
KCWI 248mm x 220mm blue band pass filter (delivered in 2015)
PAU 208mm x 203mm u, g, r, i, z, y filters (delivered in 2013)
CIAO 240mm diameter beam splitter, total 5 pcs (delivered in 2015-2016)