Double glass light transmission component parameters

What is visible light transmittance?

Visible Light Transmittance (Tv, %) is the percentage of incident light in the wavelength range of 380 nm to 780 nm that is transmitted by the glass. Visible Light Outdoors/Indoors (Re out/in, %) is the percentage of incident solar energy directly reflected by the glass.

What is the transmittance of glasses?

Often, glasses are discussed in terms of their transmittance or transmission. The same information is provided by both of these terms but transmission is reported with ranges from 0 % to 100 % and transmittance from 0 to 1.

Do optical glasses have a high transmittance range?

Optical glasses are optimized to provide excellent transmittance throughout the total visible range from 400 to 800 nm. Usually the transmittance range spreads also into the near UV and IR regions. As a general trend lowest refractive index glasses show high transmittance far down to short wavelengths in the UV.

Can we use visible light transmittance as an example?

We can use visible light transmittance as an example. If we use simple arithmetic averaging of spectral transmittance in the 380 nm – 780 nm range, the result is not reasonable, as there is more green light in natural daylight and human eyes are also more sensitive to green light.

Is weighted averaging of spectral transmittance reasonable?

If we use simple arithmetic averaging of spectral transmittance in the 380 nm – 780 nm range, the result is not reasonable, as there is more green light in natural daylight and human eyes are also more sensitive to green light. With weighted averaging, more weight is assigned to green light and less weights are assigned to other colors.

Do low index glasses show high transmittance?

As a general trend lowest refractive index glasses show high transmittance far down to short wavelengths in the UV. Going to higher index glasses the UV absorption edge moves closer to the visible range. For highest index glass and larger thickness the absorption edge already reaches into the visible range.