Recent content by Itay Segal

thanks, i think i understand what to do now. i will run some tests to see the similarities between the theory and the measurements. thanks again everybody :)

mm so if i get you correctly, i just calculate the irradiance [µW/cm^2] and divide it by the FWHM, which will give me the spectral irradiance [µW/cm^2/nm]? and to define the FWHM, i should look for a normalized power vs wavelength graph?

i didn't find anything regarding spectral irradiance in the datasheet you sent. are you sure? any specific page number?

those units sure are a pain to deal with *sigh* it's hard to believe that LED manufacturers provides spectral irradiance vs wavelengths curves, or any spectral irradiance related data, as those are heavily related on the application (put aside the fact that i didn't find any of this data at any...

well i need LEDs at a specific wavelength to treat jaundice, which requires spectral irradiance over 30 µW/cm^2/nm. for choosing the right LED at the right distance, i want to be able to calculate the spectral irradiance before purchasing it. after purchasing the LED, i will measure it, to...

in that case i agree that the receive filter admits all of the source spectrum, but shouldn't it be that way? i do want to measure it, not to filter it. I'm not aiming to receive less power while measuring. further more, I'm aiming to perform the measurements in a dark room, with only the blue...

through a measuring device. it's a response graph. Thanks, i actually found it before and even presented the graph from there. it's one of the measuring devices i consider using. from their description I'm still not sure of the exact calculation needed. i would be happy if someone gives me an...

Perhaps one of us misunderstood the other one. We are talking about a measuring device, yes? Not a filter. I want to measure the spectral irradiance, and validate it with calculation.

Thanks! i still did not fully understand the calculation needed. lets say i have a LED with irradiance of 5 µW/cm^2 & wavelength of 450-470nm, and a measurement device with a response band width of 450-500nm. if i understand it correctly: to calculate the spectral irradiance, i should do an...

also, if this is my response curve, what is the divide value?

Thanks for the response. this is the response graph of a measuring device I'm planning on using: if my LED gives me 450-470nm wavelength range, you mean i need to do an integral between 450 & 470, then divide it by the response bandwidth (50)? and btw, is the integral on a constant of the...

Thanka for the answer. That what i was thinking and found on some websites, but in others they talked about an integral on the band of wavelengths (like from 450 to 470). Any solid reference link / example solution out there?

Hi everybody, I'm a mechanical engineer working on a phototherapy project, which includes choosing a LED light source that emits a spectral irradiance of 30 µW/cm^2/nm. however, most of the LEDs datasheets giving you the lumens at best. i was able to calculate the irradiance [µW/cm^2] from...