ASC OP1 Wavefront Draft Minutes, 1-20-07

Draft Minutes

ASC OP1 Optics and Electro-Optical Instruments Optical Elements and Assemblies Wavefront Standard

Sunday, October 8, 2006, 1:30 p.m. 6:00 p.m.

Hyatt Regency Rochester, 125 East Main Street, Rochester, New York, USA 14604

Loftus C. Carlson Room, Section B

Attending

Committee Members (12 of 17)

Representing

David Aikens

Zygo Corporation.

Gordon Boultbee

JDSU

Andre Brunfeld

Xyratex

Benjamin Catching (Alternate) (by phone) JDSU
Walter Czajkowski

APOMA (Edmund Optics)

Marla Dowell

IEEE/LEOS (NIST)

Andrei Brunfeld

Xyratex

Lincoln Endelman

SPIE

John M. Hamilton

Northrop Grumman Corporation

James E. Harvey

CREOL

Hal Johnson

Harold Johnson Optical Lab

Michael Morrill

Lockheed Martin Space Systems Co.

William Royall

Eastman Kodak Company (Retired)

Peter Z. Takacs

Brookhaven National Lab

Trey Turner

Research Electro-Optics, Inc.

Steven VanKerkhove

Corning Tropel

Ray Williamson

Ray Williamson Consulting

Observers (5)

Lahsen Assoufid

Argonne National Laboratory

Charles Campbell

Self Employed

Gene Kohlenberg

OEOSC

Allen Krisiloff

Triptar Lens Co., Inc.

Stephen Martinek

4D Technology

Auditor's Summary of Meeting

The task force reviewed the purpose of the proposed wavefront measurement standard document. They also discussed

how other standards groups define Zernike polynomials. They reviewed ISO 10110 parts 5, 8 and 14, and discussed how
they could be modified to better support the US optics industry. The task force is planning to develop two wavefront
standards OP1.004 and OP1.005 using existing standards material where practical.

The purpose statements of the future OP1.004 and OP1.005 were reviewed and accepted. Drafts of the scope

statements for the two proposed standards will be prepared for review at the next meeting.

1. Welcome and Introductions

S. VanKerkhove opened the meeting at 1:38 p.m. with a round of introductions.

2. Adoption of Agenda

D. Aikens moved that the draft agenda as modified at this meeting be adopted. M. Dowell seconded the motion. The

motion carried unanimously.

04/05/07 06:33:17 PM

ASC OP1 Wavefront Draft Minutes, 1-20-07 draft.odt

ASC OP1 Optics and Electro-Optical Instruments Optical Elements and Assemblies Wavefront Standard, Continued

3. Approval of draft minutes of Sunday, October 8, 2006 meeting

D. Aikens moved that the minutes of the previous meeting be approved as presented on the OEOSC web site. L. Endelman

seconded the motion. The motion carried unanimously.

4. Review of how other groups measure wavefronts

C. Campbell ANSI Z80-28, ISO 24157. This standard was primarily written so that those in the eye care industry would report in

a standardized fashion. It tells how to convert from someone else's coordinate system to the standard coordinate system. It contains
nomenclature to describe what each term means along with the equations. D. Aikens suggested that the copy of the standard that C.
Campbell brought with him be circulated around the table. ISO/TC 172/SC 7/WG 6. This uses a slightly different notation than Born
and Wolf and also Zernike. They use 0° to the right with a counter clockwise rotation to 90°, while astronomers use a map
convention where 0° point to north with a clock wise rotation to 90°. D. Aikens could think of four different ways to write the Zernike
polynomials in the optical instruments venue. Ophthalmics use gradient fields as a communication tool rather than wavefronts. C.
Campbell said that there is a way to present the information as a magnitude and angle of orientation that is similar to how opticians
report astigmatism, etc. S. VanKerkhove said that vector pairs would be a good way of describing astigmatism, etc. P. Takacs said
that the intended audience would determine how best to specify the aberration. D. Aikens said that users want one way of specifying
parts so that there is no confusion.

A. Brunfeld said that there is no direct connection between Zernike polynomials and what the operator sees on a part. He

measures ten or twenty flat surfaces per minute; he can't take time for polynomials. A. Krisiloff asked A. Brunfeld what he meant by
wavefront aberrations. He said that what he needs to do is measure the wavefront in such a way that he can tolerance it. Testing must
be done in an easy way so that the operator can understand how to do it.

J. Harvey mentioned the measurement of scattering from surface irregularities.
D. Aikens said that there are two communities: Zernike (deterministic) and power spectrum (is it good?). If this committee came

up with a good formalism to describe surfaces with power spectrum over the next two years, that would be a good achievement.

5. Wavefront Standard

S. VanKerkhove suggested that the task force move on to the purpose of the wavefront measurement standard. He paraphrased

the information . What is difference between OP1.004 and OP1.005? D. Aikens said that the task force decided to split ISO 10110-8,
ISO 10110-5. and ISO 10110-14. OP1.004 covers ISO 10110-8 (surfaces) and OP1.005 is ISO 10110-14 (wavefront).

S. VanKerkhove read his purpose document. C. Campbell asked if the committee was going to limit itself to wavefronts? How

will the task force bring surface into the standard. D. Aikens said that the task force is interested in the surface and how it affects a
wavefront passing through it, not the general propagation of a wavefront.

A. Krisiloff still had a question about ranges.
ISO 10110-5 is for form, peek-valley, rms, Newton's rings.
ISO 10110-14 was written as an extension to ISO 10110-5 to cover long spatial frequency
B. Catching urged that even though the task force wants to chisel these in stone, let users pick the portions that they want to use.
P. Takacs suggested that the task force should think outside of box and write only one document to cover all of this.
D. Aikens said that ISO 10110-8 could be adapted for a US national standard. If the task force could get low and mid region

standards done at the same time, then the US could have a unified document. S. VanKerkhove wants to use two documents to avoid
the ball bouncing. Where is the gaping hole: the mid spacial-frequency domain statistical vs. deterministic.

L. Endelman said that OP should forget ISO needs, and write a US standard; then revise it as an ISO document. D. Aikens said

that he did not want to have to start with a blank page. He wants to use what has already been done that is useful for the optics
community.

A. Krisiloff asked if OP is talking about surface problem vs. volume problems.
S. Martinek thought that measurement should be in an informative annex in order to keep the standards development problem

manageable.

D. Aikens suggested that if 10110-8 be used as the basis so that this document would be backward compatible.
S. VanKerkhove reminded the group that the purpose statement is the why; the scope is the what.
M. Dowell moved to accepted the modified purpose statements, A. Brunfeld seconded the motion, which carried unanimously.
S. VanKerkhove volunteered to draft a scope statement for OP1.005. P. Takacs will do the same for OP1.004. The secretary will

give each one a template for the individual drafts. A. Brunfeld suggested that the scope should be completed if possible by e-mail.

D. Aikens suggested a time frame to get a draft ready for the June ISO meeting. M. Dowell did not think that it is possible

because the task force isn't meeting again until May. D. Aikens suggested that we would then have to write a position paper which
would be due sixty days before the ISO meeting. The goal is to get the ISO standard back into draft status rather than being
reaffirmed for five years.

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ASC OP1 Wavefront Draft Minutes, 1-20-07 draft.odt