ThermoS Ima

TERMINOLOGY

Light transmission (Tv) is the measurement of the ratio of the visible sunlight that is transmitted directly through glazing in the visible wavelength (380nm to 780nm). Light transmission ratio is depended on the glass thickness. A 4mm float glass has 92% light transmittance and THERMOBELT Ultra S® | Solar, 80%.

Light reflection (Rv) is the measurement of the ratio of the visible sunlight that is reflected on the glass surface in the visible wavelength (380nm to 780nm).

Direct radiation transmission ratio (Te) is the measurement of the ratio of the sunlight that is transmitted directly through glazing in the range of wavelengths from 300nm to 2500nm.

Direct radiation reflection ratio (Re) is the measurement of the ratio of the directly reflected sunlight in the range of wavelengths from 300nm to 2500nm.

Direct radiation absorption ratio (Ae) is the measurement of the ratio of the directly absorbed sunlight in the range of wavelengths from 300nm to 2500nm. Some of the absorbed energy is discharged outwardly and some inwardly. The inward radiation is called secondary heat transfer factor Qi.

COLOR Rendering Index (Ra) describes the perception of color recognition of objects viewed through an insulating unit. THERMOBELT Ultra S® | Solar 60/28 has a refractive index of 94, meaning that the objects through the glass pane can be seen with their natural color.

Shading Coefficient (SC), is the average shading coefficient of solar energy, when it is compared with an uncoated double insulating glass unit. The use of this coefficient is crucial for the cooling load calculation of a building.

Total energy transmittance ratio (g-value) is the total of the direct radiation transmission ratio (Te) and the secondary heat transfer factor. A low g-value involves a reduced light transmission ratio.

Selectivity (S) is the ratio of light transmission (Tv) to the total energy transmittance ratio (gvalue) and it is the measurement of the efficiency of the glass. The currently available maximum selectivity is achieved with THERMOBELT Ultra S® | Solar 60/28.