But if a headlamp came with an onboard led that is a fairly common chip, and an appropriate replacement e1xisted, a skilled individual could in theory replace a 6500k chip with say a 4500k chip with a much higher color rendering index.
Due to the challenges of slotting a LED
(high net intensity over a relatively large 2D area) into demanding optical situations dominated by pseudo 1-D
(halogen filaments) or pseudo 0-D point sources
(HID arcs),
every OEM LED solution I've seen uses proprietary LEDs extremely specific to their optical system. X,Y,Z center point, dimensions relative to said center point, ~180° emissions characteristics all need to match and replacing these LEDs will be surgery relative to a halogen bulb swap since they're tightly integrated assemblies. Swapping with anything other than an exact match (save for CCT/CRI) will likely result in similarly-poor performance as the typical 'PnP' HID/LED "kit" on halogen lamp assemblies with bad light distribution, glare, and the contamination/premature failure typical of most "retrofits" since you opened up a sealed assembly.
High CRI and lower CCTs may please certain slices of the market, but these are
compliance solutions: the cold cold >5000K OEM LEDs are white/efficient enough to meet regulations, CRI need only be "good enough" for safety (not sure if it's even called out in the regulations), and for more than two decades much of the market has associated high CCTs with more expensive/desirable vehicles.
I have good eyesight, and am sensitive too overly blue lamps. I am afraid that with many modern vehicles moving towards obnoxiously blue ( and lower CRI ) lamps that i will have a rather limited choice of vehicles in the coming years. As i do a significant amount of night driving.
Halogens look to be sticking around - they're presently far cheaper to implement. In another decade I expect the choices to be halogen on the lower end and LED on the high end. As the tech matures and the market finds workable optical solutions there may well be a shift away from >5000K as semistandard automotive headlamp LED formfactors emerge as winners and the demand for electrical efficiency becomes less important.
But that's just speculation on my part as an outside observer.
If it is feasibly possible will this board support such a modification? My current understanding is that the lower cct higher cri LEDs sacrifice some output. I think this would become a case by case basis.
As I alluded to above, such modifications are ill-advised and likely to result in poor-performing - thus unsafe - and markedly less-reliable results. Even if you find an exact match for the LED chip(s) you still need to integrate them with the design in a matching fashion - which means a matching MCPCB assuming they live on a standalone slug or performing SMD de-solder/re-solder operations if the LEDs live on a shared board of some sort.
Low CCT/high CRI typically has significant performance penalties relative to high CCT/low CRI. It's not like it's half the lumens but it's still enough that it might hurt reaction times hurdling along a road at night at highway speeds.
I support replaceable led modules just like Halogen and HID headlights have had for decades. You could have different CCT modules for people who may like a higher or lower CCT than what the car came with. I personally don't notice an increased perception of glare with the higher Kelvin headlights, and actually much prefer them to yellowish light from halogens. As an added benefit it will save the customer money when their $2000 led headlight fries prematurely, and they don't have to buy a whole new headlight but rather just the bulb module..
It's just as likely that some other component in the tightly-integrated system fails
(power supply, fans, high/low shield in a BiLED system) as it is the LED that fails. If the LED fails, it's so well integrated that replacing it in a reliable fashion is likely to be a
depot service situation as opposed to a bulb swap.
At some point we
might see acceptable 'PnP' LED bulbs that work in halogen optics which will perhaps cost a bit more than a set of HID bulbs but markedly less than the ~$1000 per side that OEMs are charging for LED headlamps.