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تسجيل مستخدم جديدالاعتبارات التصميمية للأشعال الضوئية للتحليل الطيفي المقيد بالتشويش
Design considerations of photonic lanterns for diffraction-limited spectrometry
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تعدد العدسات الكبيرة إلى الأدوات الفلكية هو مشكلة تاريخية بسبب التوتر بين تدفق الأداة والاستقرار. يمكن إدخال الضوء من العدسة بشكل كامل إلى الأداة، مما يحافظ على تدفق عالي بثمن ضعف نقطة الانتشار (PSF)، أو يمكن تصفية المكونات التي تتغير بالوقت من الضوء بواسطة الأشعة الموحدة (SMF)، مما يحافظ على استقرار الأداة بثمن فقدان الضوء. اليوم، يوفر مجال الفوتونيكس حلاً محتملاً للتوتر بين التدفق والاستقرار بشكل الضوء الفوتوني (PL): عبارة عن موصل منحني يستطيع توصيل PSF ذي تغير بالوقت وخاطئ إلى عدة أشعة محدودة التشويش بكفاءة كبيرة تتجاوز تحميل SMF مباشر. كذلك، تحتفظ الأدوات المغطاة بالضوء الفوتوني باستقرار الأدوات المغطاة بالأشعة الموحدة وزيادة تدفقها. لهذا الغرض، نقدم سلسلة من المحاكاة الرقمية التي تحدد الأداء الفوتوني كما تعتمد على تصميم الضوء الفوتوني والطول الموجي وخطأ الأمواج الأمامية (WFE)، مهدفة إلى توجيه تصميم المكوّنات المحدودة التشويش المستقبلية. هذه التشخيصات تشمل نظرة أولى على التفاعل بين الضوء الفوتوني والبصريات التي تسبب الشدة الأمواج (PIAA).
The coupling of large telescopes to astronomical instruments has historically been challenging due to the tension between instrument throughput and stability. Light from the telescope can either be injected wholesale into the instrument, maintaining high throughput at the cost of point-spread function (PSF) stability, or the time-varying components of the light can be filtered out with single-mode fibers (SMFs), maintaining instrument stability at the cost of light loss. Today, the field of astrophotonics provides a potential resolution to the throughput-stability tension in the form of the photonic lantern (PL): a tapered waveguide which can couple a time-varying and aberrated PSF into multiple diffraction-limited beams at an efficiency that greatly surpasses direct SMF injection. As a result, lantern-fed instruments retain the stability of SMF-fed instruments while increasing their throughput. To this end, we present a series of numerical simulations characterizing PL performance as a function of lantern geometry, wavelength, and wavefront error (WFE), aimed at guiding the design of future diffraction-limited spectrometers. These characterizations include a first look at the interaction between PLs and phase-induced amplitude apodization (PIAA) optics.
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