[HN Gopher] A photon-recycling incandescent lighting device ___________________________________________________________________ A photon-recycling incandescent lighting device Author : adrian_b Score : 24 points Date : 2023-04-14 21:46 UTC (1 hours ago) (HTM) web link (www.science.org) (TXT) w3m dump (www.science.org) | dexzod wrote: | The short lifetime of incandescent bulbs was by design | https://spectrum.ieee.org/the-great-lightbulb-conspiracy. | Otherwise they can last pretty long. This one is on since 1901 | https://en.wikipedia.org/wiki/Centennial_Light | philipkglass wrote: | Running the filaments hotter makes the bulb more efficient but | also shortens the life span due to filament evaporation. You | could get very long life by under-powering the bulb but then | the already-low efficiency of incandescent lighting would go | lower. That's the other remarkable thing about this paper. They | use a ceramic instead of tungsten as the hot emitter, and | calculate that it should have a very long lifetime. | hashmash wrote: | The Centennial Light produces very little light and isn't very | practical. https://www.urbo.com/content/the-lightbulb- | conspiracy-shinin... | philipkglass wrote: | That's remarkable. I was afraid this was going to be a pure | theory/simulation paper, but they built an incandescent light | source that selectively recycles infrared photons back to the hot | emitter, thereby dramatically improving the luminous efficacy. | It's a white light source that produces a continuous spectrum in | the visible range, like other incandescent light bulbs, but has | efficiency comparable to LED lighting. | adrian_b wrote: | TLDR: | | This paper demonstrates quite convincingly (because the | descriptions are very detailed) that the ancient Edison light | bulb (i.e. with light emitted by incandescent carbon) can be | revived by using modern technologies in a form that can be better | than the current LED lamps. | | The first incandescent lamps had 2 disadvantages, short lifetime | and low efficiency. | | The evaporation and oxidation of the incandescent carbon can be | avoided by a structure made of carbon nanotubes that works in | argon. The claimed lifetime (based on accelerated aging tests) is | as good as for LEDs. | | The low efficiency is solved by using a lossless optical filter | (i.e. one that transmits the visible light and reflects back the | infrared light) to prevent the heat loss from the lamp by | radiation other than the useful light output. | | This method can reach the maximum energy efficiency determined by | the human vision characteristics, unlike the current LED lamps, | which are unavoidably limited to a value lower than that by the | losses caused by the fluorescent light conversion. | | The design of the lossless optical filter is a difficult | optimization problem due to the large number of parameters. Their | solution, which is completely described in the paper, is claimed | to have been found by a machine-learning algorithm. | maicro wrote: | I'm not going to read the paper to check your work, but | excellent TLDR - thanks X) | muser8 wrote: | Fantastic summary! | | I wonder if the economics will make enough sense to overcome | entrenched interests and the legislation backing them. | | It be great to have efficient incandescent light and put the | failed promises of LED longevity behind us. | UncleOxidant wrote: | I don't see any discussion of manufacturing costs, anything | here that might be more expensive than current LED lighting? ___________________________________________________________________ (page generated 2023-04-14 23:00 UTC)