CONVERGENCE • Second Quarter 2004

Volume 12, Number 2 • June 2004

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Freeform Cubic Phase Plate

K. Bryant, U.S. Army Night Vision and Electronic Directorate, Ft. Belvoir, VA R. Cassin, L. Chaloux, Y. Tohme, Moore Nanotechnology Systems, Keene, NH

D. Puczek, G. Dunn, H. Takeuchi, Panasonic Factory Automation, Elgin, IL In the March 2004 edition of Convergence, graduate student Wanli Chi and Professor Nicholas George at the University of Rochester’s Institute of Optics, presented a fabrication process utilizing deterministic mi-crogrinding (DMG) and magnetorheological finishing (MRF) for a logarithmic asphere of BK7 glass to achieve extended depth of field performance in an imaging system. A parallel project was also on-going to extend the depth of field for a Long-Wave Infrared (LWIR) imaging system. A collaborative effort involving the U.S. Army Night Vision Lab, Moore Nanotechnology Systems and Panasonic Factory Automation demonstrated a successful freeform process for a cubic phase plate made of Zinc Sulfide (ZnS), which was the critical component for the imaging system. The resulting surface profile matched the formula to within ±0.20µm. This was deemed essentially perfect, because it corre-sponded to ±0.02λ in the 8-12µm region. The following are abstracts of the design, manufacturing and metrology methods in this project.

Application and Design (Kyle R. Bryant — k.bryant@nvl.army.mil)

By applying an optical distortion and digital restoration technique to digitally captured imagery, one can re-alize benefits such as extended depth of field, thermal focus shift invariance, loosened optical design toler-ances, and more. The Night Vision and Electronic Directorate (NVESD) be-gan investigating this imaging technique for Long-Wave Infrared (LWIR), low signal applications, since this is predominantly the environment that night vision technology is used. These applications call for fast, wide field of view optics with large depths of field that are covert to threats. The cubic phase plate design and geometry is shown on the next page in ex-aggerated forms. The total peak-to-valley on the actual phase plate surface is 100-microns (shown in the formula) whose coefficients are given in millime-ters. Note, the base window thickness is arbitrary, but is 3mm (thi) for this example. The total plate thickness is z, and the x/y origin is at the center of the part. The overall size of the part is 25mm x 25mm.

Inside: Freeform Cubic Phase Plate ….1–4 OEOSC Notice ...................5 Glass Art Contest ...............5 Optifab 2005 ......................6 Job Postings ......................7

Industry Calendar ..............8

© Copyright University of Rochester CENTER FOR OPTICS MANUFACTURING

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CONVERGENCE • Second Quarter 2004 2

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Slow Slide Servo (S3) Machining Process (Robert Cassin — cassin@nanotechsys.com)

In recent years, a significant amount of work has been accomplished in the area of freeform optical surface generation. Most of this work is driven by market demand for these types of surfaces, which currently in-cludes eyewear, electro-optics, LED optics, defense, automotive, and others. Presently, there are several methods to manufacture such surfaces of which the most common ones are grinding and raster flycutting. Both grinding and raster flycutting rotate the tool and traverse either the tool and/or workpiece in three lin-ear axes to cut the surface. Grinding and fly cutting can produce very accurate surfaces but require long ma-chining cycles and are difficult to set-up. Another method of fabrication is the Fast Tool Servo (FTS), which is widely applied in the contact lens industry. However, most FTS systems have a maximum travel range of less than 1mm and therefore are limited to certain part geometries with small departures.

In this project Moore Nanotechnology Sys-tems demonstrated how they perfected an alternative method of freeform optical sur-face fabrication, the Slow Slide Servo (S3). The S3 method is similar to the FTS in that, the part is mounted on the spindle and as the spindle rotates, the tool oscillates (Figure 3). Unlike the FTS method, the system does not use any additional axes for oscillating the tool; the Z-axis slide gener-ates the oscillations. Another difference is the spindle position control (or C-axis). In a FTS setup, the spindle has an encoder that feeds the position to the FTS unit without putting the spindle in position con-trol. In the S3 all axes are under fully coor-dinated position control. The S3 can oscil-late at ranges up to 25mm, is easy to set-up, inexpensive and allows the manufac-turing of highly accurate parts.

Since the material for this application is Zinc Sulfide, a negative rake diamond cutting tool was used. The sag of the surface is 100µm Peak to Valley (PV). The form results shown in Figure 5 demonstrate the PV error is 0.26µm and the surface finish shown in Figure 6 has a roughness of 4.6nm Ra.

thiyxz +

+

=

33

1010025.0

Figure 1: Phase Plate Form

Figure 2: Moore Nanotech 350UPL

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CONVERGENCE • Second Quarter 2004

We welcome your submissions! For APOMA Members only

Fax or e-mail your news and job postings to Annette Sansone at COM Fax: 585-275-7225 or e-mail: acom@LLE.ROCHESTER.EDU

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Continued from page 2

Figure 3: Set up with machining for Slow Slide Servo (S3)

Figure 4. Surface of cubic phase plate. Material: Zinc Sulfide 27mm X 27mm

Figure 5. Phase plate form accuracy results Form results (Panasonic UA3P)

0.263µm PV 0.055µm Rms

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CONVERGENCE • Second Quarter 2004

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Metrology : UA3P, Ultrahigh Accurate 3-D Profilometer (David Puczek — puczek@panasonic.com)

Panasonic’s applications laboratory in Elgin, Illinois joined the effort to provide a full aperture (20mm x 20mm) map of the surface. The Ultrahigh Accurate 3-D Profilometer (UA3P) offers the capability to measure surfaces up to 60o slope angle, exceeding the capability of COM’s interferometers and optical probe-measuring tools. The UA3P combines 3-D measurement capabilities, an interferometer function, atomic force microscopy and roughness measurement in one machine that allows measurements to be taken from objects as small as 2µm to large objects up to 400 mm. A 2µm diamond stylus was used and a user-defined equation was set up. This set up, using the customer’s 3rd order polynomial equation for the object’s surface, provided information for the UA3P to compare the measured results to the actual surface topography. The measurement type was a standard X rectangle scan for the UA3P, measuring +/- 10 mm in the X and Y from the center of the object moving at 3 mm/sec. Ap-proximately 7400 data points were collected, but changing the speed and data sampling pitch can collect more data points if needed. After the data collection, the editing features on the UA3P were used to elimi-nate any noise from the data, such as dust on the surface of the object. When editing was completed, the data was plotted directly from the UA3P in various forms, such as Zd compared to X, Y. (see Figure 5) Future Efforts: COM is exploring finishing optimization processes for improved surface finishes on poly-crystalline IR materials such as ZnS. These efforts will be reported in upcoming editions.

Finish results (Zygo NewView) 4.569nm Ra 6.077nm Rms

Figure 6. Phase plate surface finish results.

The machining tests performed with the S3 indicate that it is a very viable method for producing freeform optical surfaces. Surface finish and form accuracy results are comparable to axisymmetric diamond turning results. In addition, this method is inexpensive, does not have sag limitations, is very accurate, reduces cycle times and is easy to set-up.

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CONVERGENCE • Second Quarter 2004 5

John Sloane GLASS MOUNTAIN OPTICS INC. Austin, TX 78758 PH: (512) 339-7442 FX: (512) 339-7442

Joe Robichaud SSG, INC. Wilmington, MA 01887 PH: (978) 694-9991 FX: (978) 694-9922

Would you like to become an APOMA member? Visit APOMA website at http://www.APOMA.org

Welcome New APOMA Members!! Ken Anderson WOLCOTT-PARK, INC. Rochester, NY 14617 PH: (585) 342-3120 FX: (585) 342-3176

The Optics and Electro-Optics Standards Council (OEOSC) announces that the Accredited Standards Committee OP has completed the Optics and Electro-Optical Instruments - Optical Elements and Assemblies - Appear-ance Imperfections national standard. This workmanship standard, an updated version of the former MIL-O-13830 specification, is being submitted to ANSI for final approval, and should then be released for use by Septem-ber 2004. ASC OP is now turning its attention to a performance based standard covering scratches and digs on optical ele-ments. Anyone interested in participating in the development of this new performance standard is invited to attend the upcoming meeting on August 1, 2004, 9:00 a.m. - 4:00 p.m. in the Matchless room at the Denver Marriott City Center, 1701 California Street, Denver, CO. To register contact Gene Kohlenberg at gene.kohlenberg@toast.net, 585-377-2540, or c/o OEOSC, P.O. Box 25705, Rochester, NY 14625-0705.

A “Glass Art Contest” will be held at the OF&T Meeting, co-located with the OSA An-nual Meeting in Rochester, NY. It is intended to give optical fabricators at institutions and companies an opportunity to present unique approaches to the design and manufac-ture of glass artwork. Awards will be given for categories such as:

· Originality of design · Masterful handling of glass materials · Excellence of craftsmanship · Use of glass as a medium to express light, color, texture, line, and composition

The contest will be held on Monday evening, October 11th, from 7:30 pm until 9:30 pm. The program will begin with a presentation entitled, “Light and Glass Sculpture”, given by Fred Tschida, Professor of Glass Design and Director of the Museum of Luminous Phenomena, Alfred University. Prof. Tschida will use slides to offer a visual voyage through 30 years of research on light in sculpture. He will then convene a panel of judges to evaluate submissions and announce the winners. All entrants will have an opportunity to describe their work. The OF&T organizing committee asks that entrants join Prof. Tschida in allowing their submis-sions to be auctioned off at the conclusion of the contest, with proceeds being donated to the Hillside Children’s Cen-ter, located in Rochester, NY. Entries Entrants should register their intention to submit by providing contact information to Lisa Rich, OF&T Organizing Committee, at lisarich58@yahoo.com, by July 15, 2004. Willingness to donate artwork should be indicated at this time. All entrants must submit an electronic photo of their piece, accompanied by a title and no more than 500 words of descriptive information, to the above e-mail address no later than September 15, 2004. Transportation, storage, set-up, exhibition, and delivery of the artwork to the successful bidder is the responsibility of the entrant. Further informa-tion will be provided by the committee.

“Philosopher’s Stone” by Fred Tschida

This or a similar work to be auctioned off at

OF&T’s Glass Art Contest

Glass Art Contest

CONVERGENCE • Second Quarter 2004 6

CONVERGENCE • Second Quarter 2004

Our newsletter is also posted on the

COM website! Go to www.opticsexcellence.org

Polishing Specialist ONYX Optics, Inc., a growing and innovative crystal and glass component company, is adding to its optical manufacturing division. ONYX is the world leader in Adhesive-Free Bonding (AFB) and provides all types of bonded laser components, assemblies and other preci-sion optical components. ONYX Optics, Inc. is looking for master opticians and polishing technicians for laser optics precision polishing. Familiarity and experience with both hard and soft crystalline materials as well as glass helpful. Work is primarily for flat optics with some cylindrical work. ONYX offers competitive salary, 401K and health benefits.

Send resume to address above

Company: ONYX Optics, Inc. Oliver Meissner 6551 Sierra Lane Dublin, CA 94568 Fax: 925-833-1759 E-mail: omeissner@onyxoptics.com

Company: PPGI Bill Brucker, Director, Human Resources 181 Legrand Avenue Northvale, NJ 07647 bbrucker@ppgrpinc.com Fax: 201-767-9644

Description: This position, located and based in our cor-porate headquarters. will promote, sell and support optical components and subassemblies services, manage relation-ships with existing accounts, identify and bring in new custom optics business, maximize face-to-face customer contact and assist in implementing marketing communica-tion plans. Up to 50% travel required.

Education: Technical degrees, BS or higher in Optics, Physics with current knowledge of photonics, optics and optical coatings. Experience: Minimum 5 years of high level sales and technical/engineering in custom optics or photonics indus-try. Proven ability to cultivate and develop new markets. Strong consultative customer sales and technical support skills essential. Must be proactive and possess strong ac-count management, presentation and negotiation skills. Our competitive benefits package includes health, dental, vision, life insurance, Company matched 401K and PPGI incentive plan.

Send resume to above address

...JOB POSTINGS...JOB POSTINGS...JOB POSTINGS...

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Company: FISBA OPTIK LLC John Nemechek 3495 Winton Place, Bldg E-120 Rochester, New York 14623 Email: jjn@fisbaoptik.com Sales Engineer Description Experienced sales engineer sought to help expand sales and support of Swiss optical measurement equipment in North America. Candidate will travel 35% to meet with existing and prospective customers to demonstrate, in-stall and support Fisba’s phase-shifting interferometers in manufacturing and laboratory environments. Travel includes 1 or 2 trips annually to visit parent company in Switzerland. Employee will report to U.S. sales and marketing manager. Experience Applicants should have minimum of 8 years experience in the optics industry, with at least 4 years in sales. Strong technical, communication, organizational and computer skills are required. AAS/BS in Optics or Physics or equivalent work experience.

Send resume to address above

APOMA members please send your job postings to Annette Sansone

at acom@lle.rochester.edu or fax 585-275-7225

CONVERGENCE • Second Quarter 2004

CENTER FOR OPTICS MANUFACTURING

University of Rochester 240 East River Road

Rochester, NY 14623-1212

2004 INDUSTRY EVENTS

Frontiers in Optics/Laser Science Conference Rochester, NY October 10-14, 2004 Optifab 2005, Rochester, NY May 2-5, 2005 * * * * * * * * * * * * * Our newsletter is also on the COM website!! Go to www.opticsexcellence.org and click on ‘Newsletter’ For more information on APOMA or to become a member please see their website: http://www.apoma.org

NEWSLETTER MAILING LIST UPDATE

Please let us know of any address corrections, additions, or deletions by completing this form. Mail or fax to Annette Sansone at the Center, fax 585-275-7225.

Name: ____________________________________

Title: ______________________________________

Company: _________________________________

Address: __________________________________

City, State, Zip: _____________________________

Phone: ________________Fax: ________________

E-Mail: ____________________________________

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