Main wavelength and the peak wavelength of ir led strip

The difference between the main wavelength and the peak wavelength: WLP (peak wavelength): the wavelength of the spectral emission intensity or the maximum radiation power.
It is a kind of physical quantity, which is generally applied to the detection of a symmetrical monochromatic light. WLD (main wavelength): the eye can see the color of the main light of the corresponding main wavelength of wavelength.in the CIE1931 horseshoe coordinates, the intersection of Corresponding wavelength from the E point (0.33, 0.33). Usually you see a beam of light, it is not a single wavelength of light, it is composed of many wavelengths of light. Among them, energy light of a certain wavelength is greater than the other wavelengths of light,the wavelength is the peak wavelength(λp).each wavelength is Not Symmetric distribution in beam of light.human  was given the color from various combinations result of visible light.feeling it corresponds to a single wavelength of light, the wavelength value is lambda λd. vertical lines between a horizontal coordinate and curve at distribution curve, the curve is divided into left and right sides, the vertical line corresponding to the wavelength value is lambda λd.in General for light,It is important for us to refer lambda λd value, because the λd value better and reflect of color value more accurately;