Layered chalcogenide glass structures for IR lenses

Gibson, Dan; Bayya, Shyam; Sanghera, J.S.; Nguyen, Vinh; Scribner, Dean A.; Maksimovic, Velimir; Gill, John; Yi, Allen Y.; Deegan, John; Unger, Blair

doi:10.1117/12.2050479

Cited by 19 publications

(20 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Chalcogenide glasses have seen increasing applications in infrared detectors, moldable optics, and optical fibers, because of their wide range infrared transmission, high refractive index, high nonlinearity, and low phonon energy. In addition, chalcogenide glasses can be readily molded into precision optics, therefore providing photonics industry with material candidates for low cost and high‐performance photonic devices. In compression molding process, a softened glass blank is compressed to the desired shape at temperature slightly above its glass transition temperature.…”

Section: Introductionmentioning

confidence: 99%

Stress Relaxation and Refractive Index Change of As₂S₃ in Compression Molding

Zhou

Lee

et al. 2016

Int J of Appl Glass Sci

Self Cite

View full text Add to dashboard Cite

As 2 S 3 is one of the chalcogenide glasses that have attracted increasing interests for compression molding applications. This paper is aimed to evaluate the stress relaxation behavior of As 2 S 3 above its glass transition temperature and calculate its refractive index change during cooling. First of all, creep tests were conducted with cylinder glass specimens at three different temperatures, in order to deduce the shear stress relaxation function by using the relationship with creep compliance function. In addition, the shift factor for thermo-rheological simplicity using Williams-Landel-Ferry equation was obtained. Then, finite element simulation was implemented to verify the calculated shear stress relaxation function. The acquired shear stress relaxation function needs to be modified to compensate the influence of friction on the thickness change in the experiments, so that the simulation results using the modified shear stress relaxation would match the experiments better. Finally, the refractive index changes of As 2 S 3 at different cooling rates were modeled by using the Tool-Narayanaswamy-Moynihan model for structural relaxation behavior. It is confirmed that the slower the cooling rate is, the less the refractive index drop will be. It was also demonstrated that the refractive index drop is strictly dependent on the cooling rate logarithmically by using Tool-Narayanaswamy-Moynihan model. In summary, the results presented in this paper can provide reliable references for viscoelastic characterization of As 2 S 3 glass, crucial for compression molding or similar applications. K E Y W O R D SAs 2 S 3 , chalcogenide glass, compression molding, refractive index drop, stress and structural relaxation, viscoelastic

show abstract

Section: Introductionmentioning

confidence: 99%

Stress Relaxation and Refractive Index Change of As₂S₃ in Compression Molding

Zhou

Lee

et al. 2016

Int J of Appl Glass Sci

Self Cite

View full text Add to dashboard Cite

show abstract

“…14. (a) Layered optical design and fabrication process overview. (b) Thermal image obtained using the multi-layered lens with an uncooled LWIR imaging core (33).…”

Section: Resultsmentioning

confidence: 99%

“…Cemented doublets and triplets are commonplace for visible applications, but not commercially available for IR due to the lack of IR compatible optical cements. Gibson et al [33] reported a convenient method for fabricating novel infrared (IR) lenses that enable a reduction in the size and weight of IR imaging optics through the use of layered glass structures selected from a library of 13 chalcogenide glasses with broad IR transmission (NIR through LWIR bands). A layered lens fabrication process (Fig.…”

Section: Ir Imager Using Graded Index Chalcogenide Lensesmentioning

confidence: 99%

Recent progress in chalcogenide fiber technology at NRL

Kim

Nguyen

Shaw

et al. 2016

Journal of Non-Crystalline Solids

View full text Add to dashboard Cite

“…The preform was then molded in a custom designed die to generate internal conic surfaces. The internal surfaces generated after molding were compared with the design and computer simulation and are discussed elsewhere [8]. Since the viscoelastic behaviors of the four glass layers were matched, they did not develop significant stresses or cracks after thermal processing.…”

Section: Optics Fabricationmentioning

confidence: 99%

Design and fabrication of multispectral optics using expanded glass map

et al. 2015

Self Cite

View full text Add to dashboard Cite

As the desire to have compact multispectral imagers in various DoD platforms is growing, the dearth of multispectral optics is widely felt. With the limited number of material choices for optics, these multispectral imagers are often very bulky and impractical on several weight sensitive platforms. To address this issue, NRL has developed a large set of unique infrared glasses that transmit from 0.9 to > 14 µm in wavelength and expand the glass map for multispectral optics with refractive indices from 2.38 to 3.17. They show a large spread in dispersion (Abbe number) and offer some unique solutions for multispectral optics designs. The new NRL glasses can be easily molded and also fused together to make bonded doublets. A Zemax compatible glass file has been created and is available upon request. In this paper we present some designs, optics fabrication and imaging, all using NRL materials.

show abstract

Layered chalcogenide glass structures for IR lenses

Cited by 19 publications

References 2 publications

Stress Relaxation and Refractive Index Change of As₂S₃ in Compression Molding

Stress Relaxation and Refractive Index Change of As₂S₃ in Compression Molding

Recent progress in chalcogenide fiber technology at NRL

Design and fabrication of multispectral optics using expanded glass map

Contact Info

Product

Resources

About

Layered chalcogenide glass structures for IR lenses

Cited by 19 publications

References 2 publications

Stress Relaxation and Refractive Index Change of As2S3 in Compression Molding

Stress Relaxation and Refractive Index Change of As2S3 in Compression Molding

Recent progress in chalcogenide fiber technology at NRL

Design and fabrication of multispectral optics using expanded glass map

Contact Info

Product

Resources

About

Stress Relaxation and Refractive Index Change of As₂S₃ in Compression Molding

Stress Relaxation and Refractive Index Change of As₂S₃ in Compression Molding