Vehicle lamps with uniform apparent brightness

摘要

A Parabolic-Type reflector has a uniform Apparent Brightness over the reflector surface. A model of the reflector is divided into a plurality of elements arrayed radially around the reflector focus. Each element has a length li measured radially from the focus and perpendicular to an optical axis of the reflector, and an initial depth d-initi measured parallel to the optical axis. For each element, a light-angle αi is calculated, the angle of light from the light source subtended by the element. An Apparent Brightness is found for each element, ABi≡αi/li. The element emin with the lowest Apparent Brightness ABmin is identified. For each element other than emin a required light-angle is found, the required light-angle α-corri=ABmin×li. While maintaining li, the initial depth d-initi of the element is reduced to a corrected depth d-corri necessary to achieve α-corri.

主权项

1. An analysis method for adjusting an Apparent Brightness of a Parabolic-Type reflector used with a light source located at a focus, the method comprising:
a) creating a computational model of the reflector; b) dividing the model into a plurality n of elements e arrayed around the focus; c) for each element ei, finding an Apparent Brightness ABi quantifying an amount of light emitted by the light source that is reflected along an optical axis of the reflector; d) identifying an element emin having a minimum value of Apparent Brightness ABmin; and e) for each element other than emin, changing at least one of the dimensions or orientation of the element as necessary to achieve a corrected Apparent Brightness AB-corri=ABmin.