I found these documents that do not come from optical drive sources and support the dark tray and interior theory. I am not saying that its enough to make one drive more efficient than the other but I do say that the theory is not B.S.
Difuse reflection I note that the surface of the plastic material on the interior of my Nec tray is granular this will helps difuse light greatly in all directions Read more on Difuse reflection below.
When light strikes a rough or granular surface, it bounces off in all directions due to the microscopic irregularities of the interface. Thus, an image is not formed. This is called diffuse reflection. The exact form of the reflection depends on the structure of the surface. One common model for diffuse reflection is Lambertian reflectance, in which the light is reflected with equal luminance in all directions, as defined by Lambert's cosine law.
Para-reflections lighter colours such as white reflect more light this is a common knowledge in the motor vehicle world, white cars will stay cooler in the summmer time more so than black cars the painted surface on a black car will heat very quickly. So consequintialy the black car is obsorbing more light and reflecting less.
Read more on Para-reflections below
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