Multi Function TAIL LIGHTS








“Effective Projected Luminous Lens Area” (EPLLA) OUTPUT Analysis

 This is a beautifully made LED Array using "Conal Reflectors", which are comparable in design to the "classy" designs that a few new Autos and SUVs use. However, you must realize that this design has only a maximum possible Effective Projected Luminous Lens Area (EPLLA) of 4.5 X 2.2 = 9.9 IN² - still short of the 11-5/8" IN² needed -

    ≈4 more Cones and LEDs must be added



    Here’s Wesbar’s® (Cequent®) latest LED 6/7 Function Light that nicely flaunts the best styling use of LEDs by using expensive "Conal Reflectors", which work well to increase EPLLA when more expensive, wider spectrum, higher powered LEDs can properly and completely light the entire Conal Reflector while projecting all its output within the Federally mandated 20° Left, 20° Right; 10° Up, 10° Down "Test Pattern".

This Array apparently produces a 3 X 4 = 12in² of "EPLLA" that would seemingly qualify for the 11-5/8in² minimally required "EPLLA" output, which … for 2008 … seems to be the very first 6/7 Function "LED" Trailer, RV, Truck Tail Light Assembly that’s fully FMVSS #108 "EPLLA" compliant. It seems to be well made so it probably won’t fade; however, it is totally sealed - an approach that has never worked very long for drastically Cold to Hot, Hot to Cold applications that produces tremendous outward pressures when heating and tremendous inward pressures when chilled as much as 90°F (say, from 150°F to 60°F) when a hot light is plunged into cold water or cold water is sprayed on a hot light from a garden hose or a sudden downpour of rain.

Usually, after a few expansions and contractions, leaks occur in the best of sealed designs - then what? Then sooner, more than later, a teaspoon amount of water is "sucked in" and starts the LED degradation process along with precipitant droplets always visible on the insides, which look bad to customers and degrades the output of inside faceting and reflector reflex - then what? Also, has "Heat Loss" been compensated for when LEDs are heated on a hot day … is still to be answered!

Also, we believe a pair of these Lights Retail for $100 and therefore, probably sell to OEs for $35 to $45 per pair
- very costly! & very risky!


This Optronics® 3-1/2" x 6" LED Light uses only fourteen (14) 3/4" Diameter Fresnels lit by fourteen (14) small angled (20° / 30° output) LEDs that project to only "directly behind" following traffic. Assuming all of the Fresnel’s Rings project within the Federally mandated 20° Left - 20° Right, 10° Up - 10° Down EPLLA Test Pattern (as Mandated by FMVSS #108) - its MAXIMUM "Effective Projected Luminous Lens Area" (EPLLA) = 14 X x (3/8)² =  only 6.18 IN² . This is far below the Federal mandate of 11-5/8 IN².On their web site, Optronics® points out this Light is for use on only Under 80" Vehicles*; however, it is still not even yielding the 7-3/4 in²" of EPLLA that’s mandated for under 80" vehicles.


    Bottom line … ≈ 4 more 3/4" Fresnels and LEDs are needed for Under 80" Vehicle use and ≈12 more 3/4" Lit Fresnels are needed for Over 80" Vehicle use.
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