Optical design study in the 3-12 μm spectral band with gradient-index materials

AbstractWe discuss the findings of a recent optical design study into layered polymeric gradient index lenses (known as L-GRIN). A range of GRIN singlet lenses were designed for various aperture and field-of-view configurations. Their optical performance was compared to polymer diffractive lenses and glass-cemented doublets (both spherical and aspheric) designed to the same specification. We find that diamond-turned polymer GRIN lenses offer comparable performance to achromatic doublets and polymer diffractive hybrid elements over a significant aperture and field-of-view range. We also find that the correction potential of GRIN solutions is substantially increased when the bulk GRIN Abbé value (

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Optical design study for divertor observation at the stellarator W7-X

Review of Scientific Instruments ◽

10.1063/1.2220075 ◽

2006 ◽

Vol 77 (10) ◽

pp. 10F121 ◽

Cited By ~ 4

Author(s):

R. König ◽

D. Hildebrandt ◽

T. Hübner ◽

F. Klinkhamer ◽

K. Moddemeijer ◽

...

Keyword(s):

Optical Design ◽

Design Study

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Optical design study of the PEARL beamline at SLS

Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment ◽

10.1016/j.nima.2011.01.076 ◽

2011 ◽

Vol 635 (1) ◽

pp. 116-120 ◽

Cited By ~ 6

Author(s):

P. Oberta ◽

U. Flechsig ◽

M. Muntwiler ◽

C. Quitmann

Keyword(s):

Optical Design ◽

Design Study

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Infrared Optical Observability of an Earth Entry Orbital Test Vehicle Using Ground‐Based Remote Sensors

Remote Sensing ◽

10.3390/rs11202404 ◽

2019 ◽

Vol 11 (20) ◽

pp. 2404 ◽

Cited By ~ 1

Author(s):

Niu ◽

Meng ◽

He ◽

Dong

Keyword(s):

Detection System ◽

Optical Design ◽

Spectral Band ◽

Radiative Properties ◽

Design Parameters ◽

Reacting Flow ◽

Test Vehicle ◽

Detection Range ◽

Order Of Magnitude ◽

The Difference

Optical design parameters for a ground-based infrared sensor rely strongly on the target’s optical radiation properties. Infrared (IR) optical observability and imaging simulations of an Earth entry vehicle were evaluated using a comprehensive numerical model. Based on a ground-based IR detection system, this model considered many physical mechanisms including thermochemical nonequilibrium reacting flow, radiative properties, optical propagation, detection range, atmospheric transmittance, and imaging processes. An orbital test vehicle (OTV) was selected as the research object for analysis of its observability using a ground-based infrared system. IR radiance contours, maximum detecting range (MDR), and thermal infrared (TIR) pixel arrangement were modeled. The results show that the distribution of IR radiance is strongly dependent on the angle of observation and the spectral band. Several special phenomena, including a strong receiving region (SRR), a characteristic attitude, a blind zone, and an equivalent zone, are all found in the varying altitude MDR distributions of mid-wavelength infrared (MWIR) and long-wavelength infrared (LWIR) irradiances. In addition, the possible increase in detectivity can greatly improve the MDR at high altitudes, especially for the backward and forward views. The difference in the peak radiance of the LWIR images is within one order of magnitude, but the difference in that of the MWIR images varies greatly. Analyses and results indicate that this model can provide guidance in the design of remote ground-based detection systems.

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A Study of High-Efficiency Laser Headlight Design Using Gradient-Index Lens and Liquid Lens

Applied Sciences ◽

10.3390/app10207331 ◽

2020 ◽

Vol 10 (20) ◽

pp. 7331

Author(s):

Yi-Chin Fang ◽

Yih-Fong Tzeng ◽

Chan-Chuan Wen ◽

Chao-Hsien Chen ◽

Hsiao-Yi Lee ◽

...

Keyword(s):

Laser Beam ◽

Light Source ◽

High Efficiency ◽

Optical Design ◽

Energy Conversion Efficiency ◽

High Energy ◽

Gradient Index ◽

High Beam ◽

Liquid Lens ◽

Gradient Index Lens

In the field of vehicle lighting, due to the diode laser, its small size and high energy conversion efficiency, it can be effectively used as the headlight source of high beam. In recent years, it was adopted by European advanced car manufacturers as a new generation of automotive headlight lighting products. The current mature technology on the market is to extend the laser beam by means of reflection and to use a single high-power laser as the light source to meet the needs of surface lighting. In this research, we propose a new integrated optical design for an automotive headlight system with the rod lens, gradient-index lens (GRIN lens) and freeform lens to expand the laser beam. With regard to the diffusion of the beam by reflection and refraction, the liquid lens is used as a switch for the high beam and low beam lights to meet the needs of vehicle lighting functions and to use low-power diode lasers to synthesize the array light source. Compared with the 24-W LED headlight module available in the current market, the energy saved by this proposed optical design can increase efficiency by an average of 33%. The maximum illuminance is 56.6 lux in the high-beam mode, which is 18% higher than the standard value. Let the laser light meet the lighting requirements of regulatory standard values even beyond.

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Parasitic Flux Analysis of Cooled Infrared Detectors for Space Applications

Defence Science Journal ◽

10.14429/dsj.67.11180 ◽

2017 ◽

Vol 67 (2) ◽

pp. 193

Author(s):

Ankur Jain ◽

Amiya Biswas

Keyword(s):

Infrared Detector ◽

Optical Design ◽

Spectral Band ◽

Low Noise ◽

Flux Analysis ◽

Optical Elements ◽

Space Applications ◽

Practical Applications ◽

Spectral Bands ◽

Infrared Imager

An infrared imager measures radiations emitted by an object in specified spectral bands to determine change in object’s characteristics over a period of time. A typical infrared imager consists of focusing optics and a cryogenically cooled two-dimensional infrared detector array mounted on the cold tip of an active micro-cooler vacuum sealed with an optical window, typically known as integrated detector cooler assembly (IDCA). Detection of feeble radiant flux from the intended target in a narrow spectral band requires a highly sensitive low noise sensor array with high well capacity. However, in practical applications the performance of an infrared imager is limited by the parasitic thermal emissions from optical elements and emissions from IDCA components like vacuum window, Dewar walls which are generally kept at ambient temperature. To optimise the performance of imager it becomes imperative to estimate these parasitic fluxes and take corrective actions to minimise their effects. This paper explains an analytical model developed to estimate parasitic fluxes generated from different components of a long wave infrared imager. Validation of the developed model was carried out by simulations in ZEMAX optical design software using ray trace method after analytical computations in MATLAB.

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The EST project

Proceedings of the International Astronomical Union ◽

10.1017/s1743921311007198 ◽

2010 ◽

Vol 6 (S274) ◽

pp. 310-313

Author(s):

Francesca Zuccarello ◽

Keyword(s):

Magnetic Field ◽

High Resolution ◽

Conceptual Design ◽

Optical Design ◽

High Resolution Imaging ◽

Solar Telescope ◽

Magnetic Field Generation ◽

Medium Term ◽

Design Study ◽

Resolution Imaging

AbstractEST European Solar Telescope is a pan-european project, presently in its Conceptual Design Study financed by the European Commission in the framework of FP7, involving 29 partners, from 14 different countries. The EST project is aimed at the realization of a 4-m class telescope, characterized by an optical design and a set of instruments optimized for extremely high resolution imaging and spectropolarimetric observations from near UV to NIR. EST will be four times larger than any existing high resolution solar telescope and it is designated with the highest priority among the ground-based, medium term (2016-2020) new projects in the ASTRONET Roadmap (Panel C). The EST instruments will measure fundamental astrophysical processes at their intrinsic scales in the Sun's atmosphere to establish the mechanism of magnetic field generation and removal, and of energy transfer from the surface to the upper solar atmosphere and eventually to the whole heliosphere. The conceptual Design Study started on February 2008 and will finish during 2011. EST will be operational at the same time as major ESA and NASA space missions aimed at studying solar activity.

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