Gmail *Vik Dhillon * ------------------------------------------------------------------------ *Actual transmission data(HeII filter)* ------------------------------------------------------------------------ *Toshihiko Kimura * 5 June 2014 04:55 To: Vik Dhillon Dear Prof. Dhillon, Now I check the status of delivery by DHL website. I suppose it will be delivered to the university by today or so. I would like to send the actual transmission data. 2004 ------------------------------__------------------------------__- you need to make a new bandpass design to take into account the different coating refractive index and the full ULTRACAM optical design. 0 degree f/2.3 CWL 467.6nm 466nm FWHM 11nm 11nm ------------------------------__------------------------------__- 2014 ------------------------------__------------------------------__- Our engineer completed the simulation. New bandpass design should be CWL 467.67nm in collimated beam. ------------------------------__------------------------------__- The actual CWL in collimated beam was 467.4nm. => 467.4nm - 1.67 = 465.73nm in ULTRACAM. That is, it becomes close to the ideal CWL 466nm in f/2.3 beam, and also the CWL of previous HeII filter produced in 2004. FWHM was 11.2nm. We will polish each substrate with specified polishing tolerance as we did in 2004. Fused silica (2mm +0, -0.05) + BG39(1.55mm +0.05, -0) + Fused silica (2mm +0, -0.05) We used the same recipes as previous HeII filter in 2004. By the way, we were contacted about WFCAM IR filter by Dr. Henry in March. (He mentioned you introduced Asahi to him). I appreciate your introduction and hope we will be able to have a opportunity to provide WFCAM filters in the future. Sincerely, Toshihiko -----Original Message----- From: Vik Dhillon Sent: Friday, May 30, 2014 5:19 PM To: Toshihiko Kimura Subject: Re: Shipping schedule(HeII filter) Hi Toshihiko, Many thanks for letting me know. Regards, Vik. Vik Dhillon phone: +44 114 222 4528 Dept of Physics & Astronomy fax: +44 114 222 3555 University of Sheffield email: vik.dhillon@sheffield.ac.uk Sheffield S3 7RH, UK web: www.shef.ac.uk/physics/people/__vdhillon On 30 May 2014 05:44, Toshihiko Kimura > wrote: Dear Prof. Dhillon, (We would like to shorten the estimated shipping schedule from 10 weeks to 8 weeks). We plan to ship the filter from our plant to Sheffield by DHL next Monday. DHL tracking # will be 605 0158 940. Thanks, Toshihiko -----Original Message----- From: Vik Dhillon Sent: Tuesday, April 15, 2014 6:12 PM To: Toshihiko Kimura Subject: Re: Bandpass film design(HeII filter) Hi Toshihiko, That's great. Many thanks! Vik. Vik Dhillon phone: +44 114 222 4528 Dept of Physics & Astronomy fax: +44 114 222 3555 University of Sheffield email: vik.dhillon@sheffield.ac.uk Sheffield S3 7RH, UK web: www.shef.ac.uk/physics/people/__vdhillon On 14 April 2014 05:56, Toshihiko Kimura > wrote: Dear Prof. Dhillon, I got the PO from University of Sheffield by fax today. Thank you. you need to make a new bandpass design to take into account the different coating refractive index and the full ULTRACAM optical design. 0 degree f/2.3 CWL 467.6nm 466nm FWHM 11nm 11nm Our engineer completed the simulation. New bandpass design should be CWL 467.67nm in collimated beam. Best regards, Toshihiko -----Original Message----- From: Vik Dhillon Sent: Wednesday, April 09, 2014 6:09 PM To: Toshihiko Kimura Subject: Re: Bandpass film design(HeII filter) Hi Toshihiko, Yes, all is clear - you need to make a new bandpass design to take into account the different coating refractive index and the full ULTRACAM optical design. Thanks for the information - please go ahead. Regards, Vik. Vik Dhillon phone: +44 114 222 4528 Dept of Physics & Astronomy fax: +44 114 222 3555 University of Sheffield email: vik.dhillon@sheffield.ac.uk Sheffield S3 7RH, UK web: www.shef.ac.uk/physics/people/__vdhillon On 9 April 2014 03:41, Toshihiko Kimura > wrote: Dear Prof. Dhillon, I visited our plant yesterday and checked all records about HeII filter. We will polish each substrate with specified polishing tolerance as we did in 2004. Fused silica (2mm +0, -0.05) + BG39(1.55mm +0.05, -0) + Fused silica (2mm +0, -0.05) On thing, we need to modify the previous bandpass film design in consideration of the current refractive index of coating material. That is, our engineer found the refractive index we adopted for bandpass film design in 2004 was different from the index in 2014. Attached are the latest zemax files for ULTRACAM (when on the VLT). I hope your engineers can read these files. Also, I received the Zemax file for ULTRACAM from you in 2006. Zemax data is more helpful for us to simulate the wavelength shift than just the information, "f/2.3" in 2004. In conclusion, the new filter should have ideally CWL 466.0nm and FWHM 11nm in ULTRACAM as we manufactured in 2004. We will measure and assess the transmission curve in collimated beam (i.e. AOI 0 degree) at our plant. In consideration of the modified bandpass film design (i.e. with current refractive index of coating material) and Zemax data. My clarification makes sense for you ? Sincerely, Toshihiko ------------------------------__------------------------------__-- Toshihiko => Prof. Dhillon sent on 12 Feb. 2014 1.CIII/NIII+HeII Please check attached file. This is the same one I sent you before. We'll coat bandpass film based on that design. According to our optical simulation, I found the relationship of spectrum between collimate beam, incident angle 0 degree and convergent beam, f/2.3. 0 degree f/2.3 CWL 467.6nm 466nm FWHM 11nm 11nm We can measure the filters only under the condition, 0 degree by Cary spectrophotometer. (We cannot measure under f/2.3 !!) So I would like to define the spec under 0 degree, Target CWL 467.6nm +-1.5nm Target FWHM 11nm +-1nm -----Original Message----- From: Toshihiko Kimura Sent: Monday, April 07, 2014 7:27 PM To: Vik Dhillon Subject: Re: Updated quote(New HeII filter) Dear Prof. Dhillon, I would like it to be *IDENTICAL* (within tolerances) to the HeII filter you made for us in 2004, Thanks for your clarification. We'll check the old data and proceed with it. Regards, Toshihiko -----Original Message----- From: Vik Dhillon Sent: Monday, April 07, 2014 7:01 PM To: Toshihiko Kimura Subject: Re: Updated quote(New HeII filter) Hi Toshihiko, Great - 8 weeks would be perfect! Thanks for the revised quote - I will put the order in today. Regarding the specification of the filter - I would like it to be *IDENTICAL* (within tolerances) to the HeII filter you made for us in 2004, as I will want to use this filter in both ULTRACAM and ULTRASPEC. So, please could you ensure that the bandpass, central wavelength and optical/physical thickness are identical to the old filters. Is that ok? Regards, Vik. Vik Dhillon phone: +44 114 222 4528 Dept of Physics & Astronomy fax: +44 114 222 3555 University of Sheffield email: vik.dhillon@sheffield.ac.uk Sheffield S3 7RH, UK web: www.shef.ac.uk/physics/people/__vdhillon On 7 April 2014 10:51, Toshihiko Kimura > wrote: Dear Prof. Dhillon, Thank you for getting back to me again. Please see the attached file. (We would like to shorten the estimated shipping schedule from 10 weeks to 8 weeks). Again in conclusion, I predict new SDSS filters for ULTRASPEC will be approximate e.g. 5.3x mm ~ 5.4x mm. That is, they are parfocal for fused silica 5.4mm +/-0.05mm and also parfocal for *each other*. In my understanding, new HeII filter should be made in consideration of ULTRACAM clear filter, fused silica 5.4mm +/-0.05mm and Sloan filters for ULTRASPEC. Sincerely, Toshihiko On 27 November 2013 05:20, Toshihiko Kimura > wrote: Dear Prof. Dhillon, Thanks, I'm pretty good. I appreciate the new inquiry, but this must be bad news for you due to the extra expense ! Yes, we have the specifications sheet about the filter we provided in 2004. (Speaking correctly, the name was NBF CIII/NIII + HeII) The difference will be: -CWL should be 466nm (+/-1.5nm) in ULTRASPEC. -It should be parfocal with ULTRASPEC SDSS filters we provided in 2012. Please check the attached pdf file. Best regards, Toshihiko From: Vik Dhillon Sent: Tuesday, November 26, 2013 8:47 PM To: Toshihiko Kimura Subject: New HeII filter Hi Toshihiko, I hope all is well with you. I am writing to you to request a quote for a new HeII filter. We bought two of these from Asahi in 2004 - you can find the details in this old email: http://www.vikdhillon.staff.__shef.ac.uk/ultracam/filters/__toshi_heii_redcont_email.txt Unfortunately, one of these filters developed a hairline crack in one of the substrate layers - I think this could have been because someone overtightened the filter holder in the filter wheel. So we would like to replace it. The filter will actually be used in ULTRASPEC, which is the instrument we bought the most recent set of u'g'r'i'z' filters for from you. Would you be able to provide me with a quote for this please? Regards, Vik. Vik Dhillon phone: +44 114 222 4528 Dept of Physics & Astronomy fax: +44 114 222 3555 University of Sheffield email: vik.dhillon@sheffield.ac.uk Sheffield S3 7RH, UK web: www.shef.ac.uk/physics/people/__vdhillon *HeII filter.xls* 243K