March 20, 2014 Duncan Moore

Note: This meeting will be held at Embassy Suites Boston/Waltham

Recent Developments in Gradient Index Optics

OSA Presidential Speaker

The University of Rochester and its team members advanced three gradient index (GRIN) material paths towards mass manufacturing and developed the tools needed to integrate these GRIN materials into optical designs.
Aluminum oxynitride (ALON) gradient index materials were developed by Surmet and characterized at the University of Rochester.  The ALON GRIN materials are transparent from the ultraviolet out to the mid wave infrared region (4.5 microns) and exhibit unique chromatic properties.  Nitrogen content and dopant additives enable control of the gradient index profile.  GRIN ALON materials present a path for ALON to move beyond armored windows and domes and to become an integrated part in advanced optical design.  Surmet has developed ALON GRIN material to manufacturing readiness level 4 and is pursuing further development of dopant ALON GRIN materials. 
University of Rochester and Gradient Lens Corporation have accomplished several key advancements in glass GRIN material.  Previously, fabrication methods where a barrier for making large diameter (>20mm) radial GRINs in glass, which limited their use in commercial optical systems.  It was shown that fast diffusing ion exchange in titania silicate glass can produce large radial gradients in less than 30 days.  
Polymer GRIN materials were produced that have a large change in index of refraction (up to 0.1), and strong chromatic dispersion.  In general polymer optics are light weight, and provide additional material properties, both useful for improving optical designs.  The GRIN in the polymer provides additional degrees of freedom.  The polymethyl-methacrylate/polystyrene material developed is thermoformable, allowing for arbitrary and near net shape GRIN profiles to be fabricated that open up the design space beyond the classical axial and radial GRIN profile options.  Axial, radial, and near net shape GRINs were all demonstrated with the polymer system.  In addition gradient index prisms were modeled and fabricated characterized polymer materials.  These were used to demonstrate the useful chromatic properties of the polymer GRIN material and its potential applications in spectrometers, beam steering optics, and hyperspectral imaging.
The University of Rochester developed multiple metrology instruments for characterizing GRIN materials and their homogeneous constituents.  Metrology capabilities span from the visible to mid wave infrared wavelength regions (4.5 microns).  These instruments are used to build a library of real material data for use in optical design software. The tools were developed that allow a designer to optimize a system with a GRIN element or elements that are based on real material data.  The material data and tools to enable optical design with real GRIN materials are a key development necessary for wide spread use of GRIN optics.    Over 100 GRIN designs were done in visible, NIR, SWIR, MWIR, LWIR, or combination of these wavelength ranges.

Note: This meeting will be held at the Embassy Suites Hotel in Waltham with a sit down dinner.


Read more: March 20, 2014 Duncan Moore

April 14, 2014 - Student/Industry Forum

Student/Industry Forum

Note: A Monday Meeting to be held at Boston University

The NES/OSA in association with the Optical Society of America and its Student Chapters will be holding a Forum on Optics Jobs in New England. The optics industry is invited to join area students to talk about what graduates can look forward to when they have completed their formal education. The program will include speakers sharing their insights and experience making the transition from student to industry.


Forum Speakers will include:

The meeting will begin with networking including refreshments and a light meal, followed by a panel of up to four 10 min talks and a Q&A session, finishing with time for further discussions. Our industry panel will draw speakers from New England's diverse industrial base such as Aerospace, Metrology, Lighting and Bio-Medical.

We encourage our regular members to bring their stories, feel free to share any information about your companies or institutions, and we welcome postings for jobs or internships.


Read more: April 14, 2014 - Student/Industry Forum

May 22, 2014 - Peter de Groot

The Meaning And Measure Of Lateral Resolution In Optical Surface Topography Measurements

Note: This meeting will be at Optikos Corporation

Traditional specifications for resolving power for imaging systems rely either single numbers, such as the familiar Rayleigh or Sparrow criteria, or detailed response information as a function of spatial frequency, as in the modulation transfer function or MTF. Currently there is quite an active debate within the international standards community regarding the meaning, specification and verification of lateral resolution in a 3D height map. This debate is taking place simultaneously in commerce, where one observes a divergence by as much as a factor of ten in quoted lateral resolution for topography instruments that have comparable resolving power.  Here I make some modest proposals aimed at clarifying terminology and validation, based in part on the detailed physical behavior of optical areal surface topography instruments, including in particular phase-shifting and coherence-scanning interferometers.


Read more: May 22, 2014 - Peter de Groot

Page 2 of 2