Go to GlobalSpec.com Home
Alert   Product Alerts
Keep current on the latest products, new suppliers, and technical articles of interest to you. (See Topics)

Subwavelength, Binary Lenses at Infrared Wavelengths

From JEOL USA, Inc.
 

 
We describe the nanofabrication of subwavelength, binary lenses in GaAs for operation in the infrared. Subwavelength surface relief structures create an artificial material with an effective index of refraction determined by the fill factor of the binary pattern and can be designed to yield high-efficiency diffraciive optical elements. In this work, we designed and fabricated a circular-aperture, off-axis lens with a deflection angle of 20°, focal length of 110 /mm, and diameter of 80 yum, for operation at 975 nm. The off axis lens design has a theoretical efficiency of 92% and the fabricated lens exhibits a diffraction efficiency into the first order of 72% and 59% of the transmitted power for TE and TM polarization, respectively. A significant advantage of these subwavelength structures is that fabrication requires only a single-lithography and-etch-step process, in this case, electron-beam lithography and reactive-ion-beam etching
Product Announcements
Charles Ross and Son Company - New Storage Vessels Website Online
A new website illustrating and describing the fabrication capabilities of the company is now online. (read more)
Ascension Industries, Inc. - Pressure Vessels Product Guide
With uses as diverse as filtration & storage to vacuum condensing & torpedo testing, pressure vessels are boilers & storage tanks containing liquids or gases, designed to operate at... (read more)
ALY Fabrication, Inc. - Power Piping
ALY Fabrication, Inc. is well experienced in the fabrication and testing of low and high pressure piping systems and holds the ASME Code S Stamp for boilers and power piping. We also have extensive... (read more)
Indian Creek Fabricators, Inc. - Shearing Capacity
Indian Creek Fabricators, Inc. can take any project from inception and design through fabrication and installation being ON TIME and ON BUDGET and with the HIGHEST QUALITY!... (read more)
ALY Fabrication, Inc. - Pressure Vessels
ALY Fabrication, Inc., holds ASME Code Stamps U for Division 1 Unfired Pressure Vessels and Heat Exchangers and S for Boilers and Power Piping along with the National Board Stamps R for Repairs,... (read more)
 
Topics of Interest
OVERVIEW Key Learning Objectives What factors a process engineer must consider when setting specifications for a pressure vessel How pressure vessels are designed and what determines the... (Read More)
Rupture disks have been used for many years to protect pressure vessels from being over pressured. In addition to being used alone, the ASME Code also allows them to be used at the inlets of pressure... (Read More)
Welded and brazed joints are the most commonly used methods for joining piping components because these joints are stronger and more leak-tight than threaded and flanged joints. Furthermore, they do... (Read More)
9.4 GENERAL CODE REQUIREMENTS [1] It is essential that the ASME code requirements be understood by the designer and the individual rating and specifying the installation details of the safety... (Read More)
9.6 PRESSURE SETTINGS AND DESIGN BASIS Unfired steam boilers, that is, nominally termed "waste heat boilers" or "heat exchangers", which generate steam by heat interchange with other fluids (see... (Read More)