Ikigai Daily
WonderOptical engineering fact1,839 of 1,961

A Fresnel lens divides the curved bulk of a conventional lens into concentric zones, concentrating light with far less glass and weight.

The lens that removed its own weight

EngineeringTechnologyOceanDesign

Why it matters

The idea in context

Augustin-Jean Fresnel's nineteenth-century design preserved the light-bending angles that mattered while discarding much of the solid glass between them. Prismatic rings gathered lamp light into a powerful horizontal beam that could warn ships from far offshore. The object looks ornate, almost jewel-like, yet its beauty comes from ruthless optical editing. It is a reminder that invention sometimes means keeping the effect and subtracting the mass.

Türkçe

Aynı kart, başka bir dilde.

Fresnel merceği, geleneksel bir merceğin kalın eğrisini eş merkezli bölgelere ayırarak ışığı çok daha az cam ve ağırlıkla yoğunlaştırır.
Kendi ağırlığını azaltan mercek

Augustin-Jean Fresnel'in on dokuzuncu yüzyıl tasarımı, ışığı büken gerekli açıları korurken aradaki katı camın büyük bölümünü attı. Prizmatik halkalar lamba ışığını, açık denizdeki gemileri uzaktan uyarabilecek güçlü yatay bir demette topladı. Nesne süslü, neredeyse mücevher gibi görünür; oysa güzelliği acımasız bir optik düzenlemeden doğar. Buluşun bazen etkiyi koruyup kütleyi çıkarmak anlamına geldiğini hatırlatır.

Source trail

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Background reading: Fresnel lensAttribution and context are revised when stronger evidence appears. Corrections are welcome through the editorial page.
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