1. EE 638: Principles of Digital Color Imaging Systems
Lecture 30.2

2. Model assumptions for Layer1
Kruse-Gustavon model
Microscopic model
Linear system
Model assumptions for Layer1
Within colorant, assume ideal point-to-point interaction for scatter
Use multiplicative model to represent absorptance in passing through colorant
colorant
substrate
Layer 1
(1)
(2)
(3)
(4)

3. Layer 2: this is where scattering takes place Aside
Thin optical element
Assume
Layer 2: this is where scattering takes place
Aside
covered area transmittance of colorant
uncovered area transmittance of area
not covered with colorant

4. Spatial frequency model: Point spread of media:
(2)
(3)
Recall
temporal frequency
Spatial frequency model:
Point spread of media:
not a spatial model
but rather macroscopic
stimulus
reflection
incident
Wavelength dependent scattering
Spectral reflectance of paper

5. Should adopt a spectral model for colorant-light interaction, as well:
Layer 3 – Stage 3 to stage 4
Note that this is 2-D spatial convolution only!
Initially incident on print at top of colorant layer
Light that reaches surface of media
Light that emerges from media after scatter within media
Light that emerges from print after passing
back through colorant layer
Question: How would we compute the CIE XYZ coordinates of the reflected light?