Hello, my name is Szymon, I am a student at a technical university in Poland – Gdańsk University of Technology. I am currently working on my engineering thesis on automotive lighting, specifically researching the influence of dual-color front headlamps on driver vision parameters.
I am looking for advice – perhaps someone has already worked on a similar topic, is familiar with the subject, or could recommend some useful literature. I would also appreciate any guidance regarding the selection of light sources and lenses.
My idea is to design a headlamp with 7 LED diodes in two color temperatures: 3000K and 6000K. The concept is to place the warmer light in the center and the cooler light on the outside, with the possibility of adjusting them so that the warm light narrows in the middle and the cool light expands at the edges. This adjustment will be done manually for research purposes.
As mentioned, I am mainly interested in the proper selection of LED diodes and lenses, ideally with a cutoff line. For the purpose of my research, the beam pattern does not necessarily have to be asymmetric.
If this is the wrong section of the forum, I apologize and kindly ask for redirection.
Thank you in advance for your help and suggestions.
Welcome to the forum. I’m no optical engineer, but will attempt to provide information you may find useful. Be forewarned that flashlight and general illumination LEDs / optics may not suffice for your purposes.
Common LED TIR - Total Internal Reflection - optics (i.e. Carclo, Ledil) are fixed, producing a general beam angle per base model…
Different LED models will have varying beam angles due to varying emitter sizes / LED package optics
Surface finishes on the optic can further alter the beam with frosted finishes, microlens arrays
The larger the emitter size, the greater the beam angle
…but these tend towards round or elliptical beam profiles.
Aespheric lenses can alter the beam angle, but are either round or project an image of the LED emitter.
Variable-CCT LEDs exist, but they’re usually large “COB” designs with enormous emitter sizes. An exception would be the likes of the Nichia NF2W757G-MT, however I don’t know that its design makes for a pseudo point source between the two separate emitters within the package, thus may not make for tight collimation.
Thus, as you’re wishing for a cutoff, I don’t know that typical LED optics will work for you. You may need to experiment with a matrix of suitable automotive headlamp projectors (ellipsoidal reflector, cutoff shield, lens) to achieve your end using discrete-packaged LEDs of the desired CCT mated to a system yielding the beam width you desire. I don’t know where to source these components - perhaps from automotive suppliers or dissecting something from Amazon, ebay, Aliexpress suitable for the LED(s) you wish to experiment with. There may be specialized TIRs that can emulate an automotive-style cutoff but a quick search hasn’t turned up anything.
if this forum section isn’t the best fit, try automotive engineering forums like Engineering Stack Exchange (tagged with “automotive-lighting” or “led-design”) or industry-specific communities like Automotive Lighting Innovation Forum —they often have engineers who’ve worked on dual-color headlamp projects.
