Question

When Transmittance of the splutipn increases

Answer 1

Answer:

Transmittance is the transmission-mode analog to the reflectance. That is, transmittance is a dimensionless number defined by the ratio of the radiant flux Φt transmitted to the incident radiant flux Φi,

(6.6)

Like the reflectance, conservation of energy dictates that the transmittance for nonfluorescent materials have values in the interval 0–1, inclusive. The diffuse transmittance for real nonfluorescent materials is always less than unity.

The total transmittance τtotal of a medium can be separated into two parts, the regular transmittance τreg and the diffuse transmittance τdiff,

(6.7)

If the incident radiant flux travels through the sample under test in such a way that the exit angle can be predicted from the entry angle according to Snell's law of refraction, the transmittance is referred to as regular. When the incident flux is scattered via its travel through the sample, for example, due to surface roughness or due to volume scattering, so that Snell's law no longer applies, the transmittance is referred to as diffuse.

We do not define transmissive analogs to the reflectance factor or the radiance factor, because it is impossible to have a perfectly transmitting diffuser, or even an approximation to one. Perhaps the best one could imagine would be to have a material that reflected half of the incident radiant flux uniformly in the reflection half-space and transmitted the other half of the incident radiant flux uniformly in the transmitting half-space. But, since no material exist that approximates this behavior, we generally do not speak of a transmittance factor.