2022年6月1日 · What I need is basically the luminous efficacy of the LED (luminous flow/radiant flow). At this point I am quite sure the provided data in the datasheet is not enough to calculate that number. My rough estimate of those LED is a luminous efficacy of 300lm/W which results in a energetic efficacy of roughly 40%.

2010年5月19日 · For an LCD TV the backlight LED gives you the ligth source - the only reason for using LEDs rather than flourescent lamps is the smaller size, greater efficency and longer life. A single pixel only puts out one color (red,gree or blue) groups of three or four pixels are used to give all the colors by varying amounts of these primary colors.

2025年2月7日 · Using your LED, the easiest thing to do is place the LED a couple of meters (or more) away from your slides. Yes, the intensity will be low and you will need to be in the dark. If you know how to produce a collimated beam using your LED, you'll get brighter results.

2024年10月16日 · For me I did know about the red,blue, and green LED's of a TV screen, (I've seen them with a magnifying glass), but as you can probably see by reading my OP above, I hadn't previously thought too much about any additional details, and hadn't previously seen any in-depth discussions on the subject such as the one from PF that I linked in post 9.

2023年8月16日 · The main attributes I'm interested in is resolution and brightness. I know that a higher resolution requires less beam current since less electrons means less repulsion, but say I wanted to fit a resolution of 3840x2160 into a 34 inch screen, this is a much higher beam current per area than any crt I've heard of.

2024年10月16日 · It would be interesting if we had tunable type monochromatic LED's, so that the picture we see on a TV screen could be made from many monochromatic sources all on the perimeter of the CIE chart, rather than the broadband LED's (whose components also come from the perimeter) whose color coordinates are then a point near the perimeter, with a ...

2024年10月2日 · there is a fundamental problem with what I'm attempting. The article calls it étendue, from the French, but it's also called "acceptance" and "optical extent" which makes it impossible to design a system based around simple lenses which can take the output of a large-area LED light source and make it behave like a smaller-area gas discharge arc light source

2013年12月21日 · (A) What kind of pattern of would you get if you shone monochromatic light on a diffraction grating? What pattern of light would you get if you shone white light on a diffraction grating? My answer: With monochromatic light, you would get a pattern of alternating light and dark bands. With...

2024年12月12日 · The "60 Watt bulb" you mention apparently is a standard LED replacement bulb with an output giving approximately the illumination level as a 60 Watt incandescent bulb. To the human visual system it appears to produce White light. Judging from the spectrum you show, the actual LED in this bulb produces a narrow band of blue light.

2021年7月1日 · Crucially, the decision about whether to measure screen position (by leaving the screen in place) or slit identity (by removing the screen) was made (at random) after each photon had passed through the slit(s); so the behavior of each photon as it passed through the slit(s) depended on a decision made after that photon had passed through the ...