Important note: all the online tools require Java Plug-in which is installed on most computers. You can easily find out if Java is working on your system.

C  O  L  O  R    Science 

This is a collection of color science related tools available online for free since 1999

• 1931 CIE Diagrams remain the commonly accepted language (not necessarily the best one) to describe colors quantitatively. This site frequently uses color monitor to present color objects. CIE diagram is the foundation for building this site and they are essential for understanding many materials of this site.
• Copunctal Points are essential for creating confusion lines for dichromats (people who have only two types of cones instead of three that normal people have). Each type of dichromat has on copunctal point.
• Confusion Lines are the lines in a color space such as CIE chromaticity diagram on which colors are not distinguishable to corresponding dichromats. Each type of dichromat has its confusion line.   
• Color Vision Test is an online test based on Confusion Lines It tests different types of color vision deficiencies: tritanopia - blue blindness which is very rare,  deuteranopia - green blindness, protanopia - red blindness.   The latter two are more common and are difficult to distinguish from one another by quick test such as this one. 
• Spectral Curves compare two sets of spectral curves (e.g. color matching functions, cone fundamentals).
• Color Space explains color space and the rationale behind using CIE 1931 color space on this site.
• Color appearance simulation expresses the author's view on color apperance simulation and poses some questions about the current technology in this area.
• VPMODEL is mainly for studying why animals have different types of color visions.  However it has many tools to deal with underwater spectral irradiance change, spectral reflectance, target radiance, photopigments' spectral absorptance, etc.
• Benham's Top is one of the interesting subject color phenomena.