Research On LED Lightinh Technology Based On Chromatics Theory And Non-imaging Optics

The light-emitting diode (LED) lighting has so many advantages, including highluminous efficiency, good directivity, small size, changeable color, safety,environmental protection, and so on. LED has been widely applied in the field ofdecorative lighting and functional lighting. It leads the technology breakthrough of thefourth generation of lighting. For the LED lighting, the most important researchdirections are luminous efficacy, color temperature, light distribution, color renderingindex, and heat dissipation. The thesis mainly focuses on the problems of colortemperature and light distribution.Firstly, in this thesis, based on the principle of chromatics theory and GlassmanLaw, the color temperature matching formula is determined after the calculation. Therelationship of color coordinates and the brightness coefficient is established. Throughnumerical calculation by MATLAB, the brightness coefficient of the three primarycolors is calculated. Using the integrating sphere, the color temperature by changing thebrightness of tricolor LEDs were tested in the experiment. The different white lightLEDs and various colorful LEDs are also researched in this thesis.Secondly, based on non-imaging optics principle, the light was tracked in the thesis.Using Snell Law and energy conservation law, the free-form surface of LED lightingwas established reversely. In other words, according to the light intensity distribution ofthe target illuminating surface, the positional relationship of incident ray, reflected ray(refractive light), and the normal vector was studied. Then the optical free-form surfacewith the differential equation was constructed. The numerical result simulated byMATLAB software can guide the secondary LED lighting.In addition, the model simulation was researched using LIGHTTOOLS. Based onthe numerical solution of light distribution algorithm, the parameters of the opticalfree-form surface were constantly adjusted. The rotational symmetric surface andnon-rotational symmetric surface were both built. The raster image and the polarcoordinate intensity distribution proved the correctness of the surfaces. At last, using thedigital illuminometer, the round uniform lighting illuminometer, the rectangular uniform light and the batwing type light were tested. The iso-luminance curveconfirmed the correctness and the reliability of the algorithm.