Lambda Value of LED?

It refers to the accuracy of the wavelength of the LED at operating temperature...

...."The light emitting diodes are made of direct energy gap semiconductors. These materials are mostly three (to) five compounds such as GaAs. On forward biasing the LED excess electron hole pairs are stored in the diode. These excess electron hole pairs recombine with each other producing photons of light which are emitted to outside of the diode. The emitted light intensity is proportional to the excess charges which in turn increases linearly with the diode current.

Concerning the spectrum of the emitted light, it is concentrated in and around a specific wavelength defined by the energy gap Eg such that: Eg= hC/ Lambda. With h the the Planck s constant, C the speed of light and Lambda the wavelength of the emitted light.

By increasing the temperature, the band gap energy decreases and the emitted wavelength increases. It follows that the peak wavelength shifts to longer wavelength and therefore this shift called the red shift.

So, from the principle point of view, one can tune Lambda by varying the temperature of the LED.

...unfortunately, increasing the temperature of the diode results in decreasing its emitted light intensity.

Therefore trimming the wavelength by decreasing the temperature is beneficial since it leads to increasing the emitted light for the same diode current. For increasing the temperature the opposite is true.

As a practical consideration one would choose a LED having slightly larger wavelength than required and then cool the diode down to adjust the emitted light wavelength."....

For more information please refer to the link...

https://www.google.com.eg/#q=temperature+dependence+of+wavelength+of+the+emitted+light+from+LEDs&start=10

https://www.researchgate.net/post/How_are_the_wavelength_of_LEDs_dependent_on_temperature

Is this an infrared LED? 0.95μ = 950nm is a wavelength in the near-infrared.

No, this light is LED panel light of Philip's make to be used as street lights.

Did you look up the manufacturer's datasheet? Since you don't provide any units with this number (angle, um, °C, etc.) it could be any of a variety of dimensionless values. Since this number is less than but close to 1, I'll guess this is an efficiency value thus when consuming 60W of electric power, 3W will be dissipated as heat.

< CLEANED UP EDIT >

"Harmonic distortion indicators - Power factor

The power factor λ is the ratio of the active power P (kW) to the apparent power S (kVA). See Chapter Power Factor Correction.

The Power Factor must not be mixed-up with the Displacement Power Factor (cos φ), relative to fundamental signals only.

As the apparent power is calculated from the r.m.s. values, the Power Factor integrates voltage and current distortion.

When the voltage is sinusoidal or virtually sinusoidal (THDu ~ 0), it may be said that the active power is only a function of the fundamental current. Then:

Consequently:

Source: https://www.electrical-installation.org/enwiki/Harmonic_distortion_indicators_-_Power_factor

Thank you for sharing.

Full specification given below:

IP67, IK07, power factor-0.9, system efficiency-85lm/w, 60W, 5700K, Philips- BVP161 LED60/CW, 220-240V, ta-35°C, lambda-0.95 (no unit), 0.29A.

λ = C/f

Where,

λ (Lambda) = Wavelength in meters

c = Speed of Light (299,792,458 m/s)

f = Frequency

https://www.everythingrf.com/rf-calculators/frequency-to-wavelength

https://academo.org/demos/colour-temperature-relationship/

So at 85lm/w we have 60 * 85 = 5100 lumens @ 5700K

If ".... λ (Lambda) = Wavelength in meters ...." were that case for the product spec'd with a value of 0.95 (meters), then this wouldn't be so much an LED (light emitting diode) as it would be an MED (microwave emitting diode) as wavelengths on the order of a meter are well outside even what might generously be considered 'light' and within the the realm of microwaves.

You know, there is such a thing...

https://en.wikipedia.org/wiki/Gunn_diode

No I don't think this is the wavelength itself, but the fidelity of the device to hold variance within operating temperature to 0.95 of spec wavelength...this dealing more with irradiance level and lack of redshift characteristic of LED...It's a quality control claim then....at least that's my take....

That is a much more plausible take than I originally understood you to be proposing.