Having put a few more hours into this little project I feel it has reached a point where it might be worthy of its own thread.
What is Chroma? Well, it is a tool for calculating the chromatic coordinates of mixtures of monochromatic light and displaying them in a CIE xy chromaticity diagram. Simply put, it answers the question: If I mix these lasers, what color will I get?
It should be a very useful tool to consult when designing and building laser projectors, especially if lasers of more exotic wavelengths for which there is a lack of guidelines are involved. Systems of different wavelengths and powers can easily be evaluated for luminance and white balance.
Capabilities of the program:
- Calculate the CIE xyY coordinates for a mixture of up to 100 monochromatic sources using the Judd-Vos (1975) color matching functions.
- Display the chromatic coordinates and gamut of the system in a zoomable CIE xy chromaticity diagram in sRGB using D65 as the white point.
- Print or save diagrams in a large number of formats (including JPEG, PNG, PDF and Illustrator).
Limitations:
- Wavelengths are limited to 380 to 825 nm with 1 nm resolution (spline interpolated from 5 nm).
- The chromaticity diagram is converted to sRGB, which means that most colors are outside of its gamut (and thus not correctly displayed). Keep in mind that most computer displays can't even display the whole sRGB gamut.
- The calculated chromatic coordinates are only completely accurate for a beam reflected off a perfectly white surface. Viewing a beam in particle-free air will yield a different color due to strongly wavelength dependent Rayleigh scattering. In fog or haze the deviation will be far smaller as Mie scattering is only weakly wavelength dependent.
- Requires MATLAB Compiler Runtime (MCR) 7.9 to run.
Installation instructions:
If you have MCR 7.9 installed already, you only need the small executable. In any other case you will need the large file (250 MB), which contains an installer for MCR 7.9. Download the required executable from here to the directory you wish to run it from. Run the exe you downloaded (and follow the installation instructions if you need to install MCR).
I have rewritten a significant portion of the code since the previous release. In particular the code for the colors of the chromaticity diagram has been completely rewritten to produce a far more accurate diagram.
I have attached a screenshot so you can easily see how the program has improved.
Download mirror:
http://tocket.mine.nu/Chroma/