Lighting apparatus for vehicles
AssigneeHella GmbH & Co. KGaA
InventorMichael Schöne
Life of this patent
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Abstract
A lighting apparatus for vehicles with a number of semiconductor-based light sources and a projection device for generating the specified light distribution with a cut-off line. The projection device features a correction device with at least two lenses. The surface of at least one of the lenses is designed as a diffractive lens surface for achromatization in a visible wavelength range. The two lenses are made from different lens materials. The surfaces of at least two lenses are designed as refractive lens surfaces that have their optical power calculated based on a temperature range and/or expansion coefficient of the lens material of at least two lenses such that adding the optical power of the lenses yields a predefined total optical power of the correction device.
Claims18
A lighting apparatus for vehicles comprising:
- a plurality of semiconductor-based light sources;
- a projection device for generating a specified light distribution;
- a correction device of the projection device, said correction device having at least two lenses, wherein at least two of said at least two lenses are made from different materials from one another, where the surface of at least one of the lenses is designed as a diffractive lens surface featuring a Fresnel structure for achromatization in a visible wavelength range,
- wherein the surfaces of at least two lenses are designed as refractive lens surfaces that have their optical power (φref1, φref2) calculated based on at least one of a temperature range and expansion coefficient of the lens material of at least two lenses such that adding the optical power (φref1, φref2, φdiff1, φdiff2) of the lenses yields a predefined total optical power (φ) of the correction device.
A lighting apparatus for vehicles comprising:
- a plurality of semiconductor-based light sources;
- a projection device for generating a specified light distribution;
- a correction device of the projection device, said correction device having at least two lenses, wherein at least two of said at least two lenses are made from different materials from one another, where the surface of at least one of the lenses is designed as a diffractive lens surface for achromatization in a visible wavelength range,
- wherein the surfaces of at least two lenses are designed as refractive lens surfaces that have their optical power (φref1, φref2) calculated based on at least one of a temperature range and expansion coefficient of the lens material of at least two lenses such that adding the optical power (φref1, φref2, φdiff1, φdiff2) of the lenses yields a predefined total optical power (φ) of the correction device, and
- wherein a first lens and a second lens each feature a diffractive lens surface and a refractive lens surface.
A lighting apparatus for vehicles comprising:
- a plurality of semiconductor-based light sources;
- a projection device for generating a specified light distribution;
- a correction device of the projection device, said correction device having at least two lenses, wherein at least two of said at least two lenses are made from different materials from one another, where the surface of at least one of the lenses is designed as a diffractive lens surface featuring a Fresnel structure for athermalization;
- wherein the lens surface of at least two lenses is designed as a refractive lens surface for achromatization in a visible wavelength range,
- wherein the optical power of the refractive lens surface is calculated based on at least one of a temperature range and expansion coefficient of the lens material of at least two lenses such that adding the optical power of the lenses yields a predefined total optical power of the correction device.
A lighting apparatus for vehicles comprising:
- a plurality of semiconductor-based light sources;
- a projection device for generating a specified light distribution;
- a correction device of the projection device, said correction device having at least two lenses, wherein at least two of said at least two lenses are made from different materials from one another, where the surface of at least one of the lenses is designed as a diffractive lens surface for athermalization;
- wherein the lens surface of at least two lenses is designed as a refractive lens surface for achromatization in a visible wavelength range,
- wherein the optical power of the refractive lens surface is calculated based on at least one of a temperature range and expansion coefficient of the lens material of at least two lenses such that adding the optical power of the lenses yields a predefined total optical power of the correction device,
- wherein a first lens and a second lens each feature a diffractive lens surface and a refractive lens surface.
Dependencies are inferred from the claim text.