Arrangement of light shaping optical elements for automotive signal lighting
A vehicle includes individual light sources that are separated in space from neighboring light sources. Collimators can collimate light emitted from the light sources, and a first diffusing surface is configured to receive the collimated light and to diffuse the collimated light in a first direction transverse to a first propagation direction of the collimated light. A second diffusing surface is configured to receive the light diffused by the first diffusing surface and to diffuse the received light in a second direction transverse to a second propagation direction of the collimated light.
1 . A vehicle light comprising:
a plurality of individual light sources, each light source being separated in space from neighboring ones of the light sources;
a plurality of collimators configured to collimate light emitted from the light sources, each collimator including a refractive symmetric lens surface configured to focus the light emitted from a light source;
a light-shaping element having a refractive index of greater than 1.4 and which includes:
a first diffusing surface located at a first interface between the light-shaping element and air around the light-shaping element and at a first light-path distance from the light sources, the first diffusing surface being configured to receive the collimated light into the light-shaping element and to diffuse the collimated light predominantly in a first direction transverse to a first propagation direction of the collimated light, such that the diffused light has an angular distribution in the first direction that is greater than an angular distribution of the light in a direction that is perpendicular to the first direction and to the propagation direction; and
a second diffusing surface located at a second interface between the light-shaping element and air around the light-shaping element and at a second light-path distance from the first diffusing surface, wherein the second interface is located at a surface from which the light exits the light-shaping element, the second diffusing surface being configured to receive the light diffused by the first diffusing surface, which propagates within the light-shaping element from the first diffusing surface to the second diffusing surface, and to diffuse the received light predominantly in a second direction transverse to a second propagation direction of the collimated light, the second direction being transverse to the second propagation direction, such that the diffused light has an angular distribution in the second direction that is greater than an angular distribution of the light in a direction that is perpendicular to the second direction and to the propagation direction,
the first propagation direction being a direction in which light propagates after being diffused by the first diffusing surface and before being diffused by the second diffusing surface, and the second propagation direction being a direction in which light propagates after being diffused by the second diffusing surface, the second direction in which the light is diffused by the second diffusing surface being parallel to the first direction in which the light is diffused by the first diffusing surface wherein the second propagation direction is anti-parallel to the first propagation direction.
2 . The vehicle light of claim 1 , wherein the vehicle light is selected from the group consisting of a taillight, a daytime running light, a brake light, a turn signal light, and a CHMSL.
3 . The vehicle light of claim 1 , wherein a diffusion angle of the light diffused by the second diffusing surface is greater than an inverse tangent of a quotient of the second light-path distance and the distance between neighboring light sources.
4 . The vehicle light of claim 1 , wherein a diffusion angle of the light diffused by the first diffusing surface is greater than an inverse tangent of a quotient of the first light-path distance and the distance between neighboring light sources.
5 . The vehicle of claim 1 , wherein light propagating in the light-shaping element experiences total internal reflection at least one of the first diffusing surface and the second diffusing surface.
6 . The vehicle of claim 1 , wherein each of the collimators is configured to collimate light emitted from the light sources into a solid angle of less than five degrees.
7 . The vehicle of claim 1 , wherein the collimators, and the first diffusing surface are configured such that a first linear light pattern from the plurality of individual light sources is formed on the second diffusing surface, the first linear light pattern having intensity maxima and minima along a longitudinal axis of the first linear light pattern corresponding to the light sources that are separated in space from each other, the difference between the intensity maxima and minima being less than 50% of the maxima.
8 . The vehicle of claim 1 , wherein the collimators, the first diffusing surface, and the second diffusing surface are configured such that a linear light pattern from the plurality of individual light sources is formed at a distance five meters away the second diffusing surface, the linear light pattern having intensity maxima and minima along a longitudinal axis of the linear light pattern corresponding to the light sources that are separated in space from each other, the difference between the intensity maxima and minima being less than 50% of the maxima.
9 . The vehicle of claim 8 , wherein the difference between the intensity maxima and minima is than 20% of the maxima.
10 . The vehicle of claim 1 , wherein the second diffusing surface has a normal direction, relative to a fixed coordinate system, that changes in a direction along the second direction transverse to a second propagation direction over a length scale that is greater than a wavelength of the light.