It is a specialized material for thin film spectral effects. Its difference from a specially configured Dali Physical is the ability to render film without a substrate, for soap bubbles, for example.
The thin film adds the spectral effect of light phase interference and calculates reflection and refraction according to the laws of wave optics.
Attention: this effect is only possible in spectral mode and the material is ignored in RGB mode and the effect is not predictable.
For greater effect, the difference between the IOR of the film and the surrounding material (body or air) should be maximum.
All fields for the thin film material are similar to those for dielectric material. The only addition is the Thickness field.
Reflection
The intensity and color of the reflection.
Edge
This is a non-physical parameter that interpolates the reflection color between Reflection and Edge depending on the Fresnel coefficient. Must be 0 to match physics.
IOR
Refractive index (real part). Determines the strength of the reflection and the amount of refraction.
Transmission
This is a physical parameter that determines the color when a beam passes through a dielectric. If the Depth parameter is specified, then the Transmission value is the color that the white light will acquire after traveling the Depth distance.
Depth
Determines the distance at which white light will acquire the color specified in the Transmission parameter.
Light in a material decays exponentially, and different wavelengths decay at different rates. This parameter sets the "speed" of the decay.
Thickness
Specifies the film thickness in microns. This parameter has the greatest influence on the nature of the interference pattern.
Body
Includes the presence of a substrate material (metal, dielectric, or a mixture of both).
Substrate settings are completely similar to the RTCD core settings of the Dali Physical
Example 1: Soap film with procedural thickness (soap bubble).
Example 2: A drop of water coated with iron oxide.
Example 3: Steel sphere with oxide film of procedural thickness.
