Equivalencia candela lumen9/19/2023 If we do the CSLNM1.TG, we get 324.5 lumens from the calculator, again very close to the rated 325 lumens. Putting that into the calculator then gives 514 lumens, extremely close to the 515 spec. Here I used cos(1.025*angle) instead of just cos(angle) in order to make the function match the datasheet more closely: If we put 171cd intensity and 1.59*1.25 = 1.9875mm^2 die size we get 86cd/mm^2 and 537 total lumens.Īs I mentioned earlier this is a slight overestimate because of what you can see in the first image.Ĭorrecting for non-lambertian distribution: Here you can see that flat LEDs have almost a perfect Lambertian distribution (orange line), although the intensity drops slightly faster at large angles near 90 degrees, so the lumen numbers given by the calculator are a slight overestimate.īy setting the intensity (candela) and LED die size based on test or datasheet info, the luminance is calculated (cd/mm^2) and then you can adjust the min and max angles of light collection.įor example, the CSLPM1.TG has 171cd and 515 lumens at spec. If the LED does not follow the Lambertian distribution, a special function needs to be used instead of cos(). These LEDs have an intensity that follows Lambertian distribution, which means that the intensity of the LED is proportional to cos(angle), making it very simple to put inside the calculator. (but it can do other LEDs if you put in some effort) HortScience 18:818-822.This works only for no-dome LEDs such as the black flat, white flat, or CFT90. Photometric, Radiometric, and Quantum Light Units of Measure: A Review of Procedures for Interconversion. It is used commonly to describe PAR in the 400-700 nm waveband.ĭefinition Source: Thimijan, Richard W., and Royal D. This term is based on the number of photons in a certain waveband incident per unit time (s) on a unit area (m2) divided by the Avogadro constant (6.022 x 10 23 mol -1). Micromole: per second and square meter (µmol m -2 s -1). While commonly used as a unit for photosynthetically active radiation (PAR), the einstein is not an SI unit. The second definition has the einstein equal a mole of photons. The einstein has been used to represent the quantity of radiant energy in Avogadro's number of photons and also Avogadro's number of photons. Microeinstein: per second and square meter (♞ m -2 s -1). LUX: one lumen per square meter differs from foot-candle by about a factor of 10. This corresponds to 683 lumens per watt of radiation at approximately 555 nm wavelength, which is near the maximum of the standard photopic spectral luminous efficiency curve. 1979, decided that the candela is the luminous intensity of a source emitting monochromatic radiation of frequency 540 x 1012 Hz and radiant intensity 1/683 watt per steradian. The 16th General Conference on Weights an Measures (CGPM), Oct.
0 Comments
Leave a Reply.AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |