We define a color space as homogeneous if it contains a continuum of colors that are uniformly aligned with one another in all spatial directions. The decisive factor in assessing this uniformity is human visual perception. As a fixed reference pattern, the window scheme enables us — even with the finest nuances — to make unambiguous and repeatable determinations regarding the distance between colors and their relative alignment.

One dimensional color series

The first step towards a homogeneous color space is a simple series of colors equally spaced along a straight line. We can arrange several such color series until we can no longer find a coherent subsequent color using the window scheme. At this point, we have reached the outer edge of our color space. Click on the following image to create your own color series interactively:
Color series and Window scheme

Two dimesonal color chart (color plate)

Different color series are related to each other. By testing across and diagonally, we can create uniform two-dimensional color charts. Click on the following image to mix your own homogeneous color plate:
Color plate and Window scheme