Rearlighting technology by Marelli Automotive Lighting

Rearlighting – basic optical principles

The light pattern of a LED-chip, distributed in an angle of 180°, needs to be captured, focused, reoriented and distributed towards other traffic partners.

As optical elements we may use simple or numerically calculated reflexion surfaces, Fresnel optics, prismatic lenses, different kinds of light guides such as tubes, bars or curtains. For the final distribution of the beam pattern we apply surfaces of frozen appearance or over-molded film layers.

These optical concepts generate together with the outer shape the dedicated lamp appearance.

From technology to aesthetics


with 20 + 20 LEDs

LEDs on a flat rigid (2D) electronic board provide the opportunity to apply deep optical elements generating a tree-dimensional appearance (3D) of the product.

Energy consumption: 11 Watt
Luminous flux: 40 lm
Optical efficiency: 12–18 %

Mirror Effect

with 6 + 6 LEDs

Retro-reflective inner lenses behind a semi-transparent outer lens create a mirror effect reflecting several times the appearance of a light emitting element.

Energy consumption: 6 Watt
Luminous flux: 36 lm
Optical efficiency: 3–7 %

Slit design

with 17 + 18 LEDs

Light sources sitting behind a partially transparent inner optics create a very slim slity appearance. Those zones are relatively free for design application.

Energy consumption: 13 Watt
Luminous flux: 105 lm
Optical efficiency: 7–13 %

Film technology

with 2x33 + 3 LEDs

Thick 3-dimensional transparent plastic parts with thin film surface provide the opportunity for creating homogeneous thick elements within taillamps.

Energy consumption: 5 Watt
Luminous flux: 138 lm
Optical efficiency: 3–7 %

Light curtain

with 3 LEDs

LEDs are feeding into the outer contour of a lightguide. Flat zones with free graphical design opportunities provide a semi-transparent impression: „light curtain“.

Energy consumption: 2.5 Watt
Luminous flux: 36 lm
Optical efficiency: 5–11 %

Light bars

with 3 + 3 LEDs

LED light sources fire laterally into a three-dimensional light guide with surface optics creating the design appearance of a thick light bar.

Energy consumption: 3 Watt
Luminous flux: 36 lm
Optical efficiency: 3–7 %

Light tubes

with 2 + 2 LEDs

Longitudinal light guides with axial circular shape. Intersections on rear side of the tube ensure outcoupling toward the observing eye on the outside.

Energy consumption: 2.5 Watt
Luminous flux: 24 lm
Optical efficiency: 12–18 %

Shell reflectors

with 12 LEDs

LED light source emit their beam towards a shell-like shaped reflector with defined optical surfaces. Those shell reflectors generate the light distribution.

Energy consumption: 9 Watt
Luminous flux: 144 lm
Optical efficiency: 20–30 %

Dot design

with 18 + 12 LEDs

The LEDs are sitting axial within small tulip-shaped reflector units generating a spotty appearance towards the observer.

Energy consumption: 8 Watt
Luminous flux: 30 lm
Optical efficiency: 20–30 %

Prismated optic

with 9 + 9 LEDs

Lenses with prismatic surface sitting between the light source, the primary optical element and the observing eye are creating a crystal appearance of the function.

Energy consumption: 14 Watt
Luminous flux: 216 lm
Optical efficiency: 20–30 %

Light sources