Talk:LED filament

Translating the German article
Is there anybody who could translate the German article? --Liebeskind (talk) 18:04, 15 July 2015 (UTC)

Informal investigation
See https://www.youtube.com/watch?v=25j2C4jq2HI

http://www.ledinside.com/knowledge/2015/2/the_next_generation_of_led_filament_bulbs

Patents
The article links to two patents both filled in 2013, yet the article also mentions an LED filament made by Ushio Lighting in 2008. Wouldn't the patents be invalid due to prior art? SonnyBS (talk) 12:37, 11 October 2016 (UTC)


 * Interesting question. I've added a ref to the 2008 patent.
 * Three possibilities suggest themselves:
 * The later patents recognise the earlier patent. They may licence parts of it. It's hard to do this absolutely for a patent (as you describe), but it could be how they're being manufactured today.
 * The later patents avoid the earlier patent. Patents are horrid things, IMHE, they're re-written by lawyers until they no longer represent the invention, then they're argued over as to whether they avoid prior art. Original inventors lose out, those with the most argumentative lawyers afterwards win.
 * Now I'd not seen filament LEDs until very recently, and white LEDs date from 2009. So why the gap? Why did it take so long? Is it (a wild surmise before I've had time to check) that the later patents are a necessary condition for workable manufacture? So the filaments that are now widespread are based on the 2013 novelty, not just the 2008 patent.
 * The manufacturers are simply ignoring the patent licensing and doing what they like. Again, a possible and pragmatic explanation of manufacture, unlikely (although certainly possible in the US) for patent filing. Andy Dingley (talk) 15:37, 11 October 2016 (UTC)

dim
Many LED bulb replacements have a regulating power supply, such that output deosn't vary with supply volage, over a reasonable range. But that doesn't allow for dimming. For dimming, either the power supply has to sense the input and adjust accordingly, or not regulate in the first place. LED filament lamps might be used more often where dimming is expected. Gah4 (talk) 02:23, 15 January 2023 (UTC)