Vehicle lamp with cornering function and a cornering optical element for the lamp

Abstract

Vehicle lamp with cornering function and a cornering optical element (2). The element comprises an input protrusion (3), on a back side of its body (4), for coupling light from at least one light source (1) into the cornering optical element (2). The element further comprises an output lens surface (5), on a front side of the body (4), for outputting light for providing the cornering function, and comprises a reflection sidewall (6) extending between the front side and the back side of the body (4). The input protrusion (3), the output lens surface (5) and the reflection sidewall (6) are from a single piece of material and are configured for directing light from the at least one light source (1) towards the reflection sidewall (6) by the input protrusion (3), and for reflecting the light on the reflection sidewall (6) towards the output lens surface (5).

Description

Technical field

[0001] The present invention relates to headlights for vehicles, more specifically to cornering illumination function and an optical element which can provide this function.Background of the Invention

[0002] A cornering illumination function is a known function of automobile headlights. It provides a laterally inclined beam of light which is activated when the automobile is turning in order to provide more light in the area towards the vehicle is being turned. While standard headlight illumination functions, such as high beam, low beam, daytime running light etc., are generally oriented to the front, to illuminate the road ahead or to be visible for incoming drivers, the cornering function is significantly inclined to one side. This allows drivers to e.g., spot any obstacles they could collide with during steering.

[0003] The cornering function thus improves illumination on curves or intersections, and helps drivers see the road's layout, pedestrians, and potential obstacles earlier. There are two primary types of cornering headlights: static and dynamic. Static cornering lights are fixedly inclined to one side and are turned on e.g., based on angle of the steering wheel. Dynamic cornering lights are provided with actuators and their inclination can thus be varied, e.g., based on how much the wheels are turned.

[0004] An example of a headlight with a dynamic cornering function is described in document US6341884B1. A movable reflector is provided in this document which can direct a beam of light to one side to provide the cornering function.

[0005] One disadvantage of known cornering lamps is their complexity and cost. Dynamic cornering requires actuators, control units and space around the light for its movement. Static cornering lamps also require a significant amount of space, since they are inclined relative to other illumination modules or components, the require individual PCBs since their light sources also have to be inclined, or they require reflectors to incline the light, which again requires space, increases cost and also decreases illumination efficiency.

[0006] It would therefore be advantageous to provide a lamp with a cornering illumination function, which could have less parts, higher efficiency, could take up less space and / or could be cheaper to manufacture.Summary of the Invention

[0007] The shortcomings of the solutions known in the prior art are to some extent eliminated by a vehicle lamp with cornering function comprising at least one light source, and a cornering optical element. The cornering optical element comprises a body, and an input protrusion, which is on a back side of the body. The input protrusion serves for coupling light from at least one light source into the cornering optical element. This at least one light source can thus be direction towards the protrusion and the light enters the cornering optical element through the protrusion.

[0008] The body of the cornering optical element further comprises an output lens surface, on a front side of the body. The lens surface serves for outputting light from the optical element for providing the cornering function. The front side is closer to the area in front of the lamp, in a standard direction of travel of a vehicle with the lamp. The direction of travel corresponds to a longitudinal axis of the vehicle and is usually marked as x-axis. The back side is on the opposite side of the body, i.e., it is closer to the passenger area.

[0009] The cornering optical element further comprises a reflection sidewall extending at least part of the way between the front side and the back side of the body. The input protrusion, the output lens surface and the reflection sidewall are from a single piece of material and are configured, especially by their shape, orientation and arrangement relative to each other and to the at least one light source, for: Directing light from the at least one light source towards the reflection sidewall of the cornering optical element by the input protrusion. In other words, the light enters the optical element, is processed by the input protrusion and sent towards the reflection sidewall. Reflecting the light on the reflection sidewall towards the output lens surface. Preferably this reflection is the result of a total internal reflection, but it is also possible to provide a reflective coating to the reflection sidewall. The light processed by the cornering optical element is thus reflected on one sidewall of the element.

[0010] Most of the light provided by the at least one light source is thus directed towards one side of the element - the side with the reflection sidewall. Preferably, it is a vast majority of the light, e.g., at least 80% or at least 90% of light which enters the cornering optical element is sent towards the sidewall. The input protrusion is thus adapted to direct light towards one side (to the left or to the right), e.g., to make the whole inputted light beam more inclined relative to an optical axis or the x-axis of the vehicle carrying the lamp.

[0011] A cornering illumination function is standardly inclined relative to other illumination functions. It is intended for illumination of areas not directly in front of the vehicle, especially during turning. It can for example by inclined by at least 45° relative to the x-axis when viewed from above. The reflection by the reflection sidewall, preferably together with light directing by the input protrusion and / or the lens surface, can be used in the present invention to incline the light as needed for the cornering function. A need for further optical elements for changing the inclination of this light can thus be removed by the invention.

[0012] The fact that the inclination is at least partially achieved by the reflection sidewall, which is in the same piece of material as the output lens surface, also helps achieving the desired inclination in a smaller space, since there is no air-to-lens boundary between the reflection sidewall and the output lens surface. If the reflector was separated from the lens, there would be at least one further optical boundary between them which would bend the light closer to the optical axis and thus decrease the angle.

[0013] The output lens surface can form any type of lens - it can be a smooth curved surface such as spherical, parabolical or freeform lens, it can be Fresnel-type lens made from a number of distinct subsurfaces, it can comprise micro-optical elements etc. It is designed, especially by a computer simulation, to bend the light into an appropriate direction for the cornering function, and it can increase the homogeneity of the light. The reflection sidewall can be planar or curved, flat or provided with optical sub-elements, it can be a single surface or multiple surfaces, etc. The reflection sidewall can also be provided by an optical simulation software. The simulation can provide a shape of the lens surface and / or the reflection sidewall and / or the input protrusion based on parameters such as type and position of the light source, material of the element, desired direction of outputted cornering beam, shape and position of the lens surface and / or the reflection sidewall and / or the input protrusion, etc.

[0014] The input protrusion can have any shape, especially an elongated substantially cylindrical or conical shape. It can be located substantially in the center of the back side, or it can be closer to one side. It can especially be closer to the side of the optical element where the reflecting sidewall is located, or closer to the opposite side. It can include one or more entry surfaces for the light. The input protrusion's side surface(s) can serve for entering of the light into the optical element, and / or they can serve for reflection of light towards the reflection sidewall. The input protrusion can include a cavity and the at least one light source can be at least partially located in this cavity.

[0015] The material of the cornering optical element can be at least partially transparent or translucent. It can be glass or a polymer, such as polycarbonate, PMMA or silicone.

[0016] The invention can provide the cornering function in a more compact lamp when compared to a lamp where the reflection on a reflection sidewall would not occur. Due to the relatively large angle of the cornering function relative to the x-axis and the direction of travel (for example, 60° is required by regulations in some countries), a lamp for providing the illumination without further optical elements and without reflection on a sidewall would need to be very wide to provide enough space for propagation of light from an entrance into the optical element to an exit for the light from the element.

[0017] Since the use of the reflection on the sidewall with the input protrusion and lens surface, which are all from a single piece of material, can eliminate a need for further optical elements, the invention can also provide the cornering function more efficiently than known lamps. When the light is processed in a single piece of material, there are fewer optical boundaries the light needs to cross and thus there are fewer places where light loss can occur.

[0018] Preferably, the cornering optical element does not contain any optical boundaries which the light would have to cross during its travel through the optical element, except at the input protrusion and the output lens surface. I.e., there are preferably no holes or cut-outs in the optical element such that the light would leave the optical element and then enter it again. Such a boundary would especially be boundary between the material of the cornering optical element and air. Another such boundary might be between the material of the element and a reflective material provided on the reflection wall.

[0019] Preferably, a light beam outputted by the light source providing light into the input protrusion, before this light enters the cornering optical element, is angled with respect to a light beam outputted from the cornering optical element by at least 15°. In other words, the cornering optical element preferably increases inclination of inputted light by at least 15°. This inclination can be measured from above, when the lamp is installed in a vehicle. Preferably, this angle is at least 30°, more advantageously, it can be at least 40° or at least 50°. The angle of a beam of light can be measured from an axis of the beam of light - it can be a main propagation direction of the light forming the beam, e.g., given as an average direction over all the light forming the beam.

[0020] This angle allows the lamp to provide the cornering illumination function with a light source oriented substantially towards the front. The light source can thus e.g., be placed in the same plane as other light sources from the lamp for further optical functions. The lamp can also be more compact since the cornering components can be aligned with components for the further optical functions, with less space in-between.

[0021] The angle of at least 15° between the light beam outputted by the light source providing light into the input protrusion and the light beam outputted from the cornering optical element can be partially provided by bending of light by the input protrusion and can be partially provided by bending of light by the output lens surface. The reflection side wall can also influence this angle. For example, the angle can be 60°, such that the cornering light beam is directed 60° towards the left or towards the right, while the light source is oriented directly forward. The 60° angle can e.g., be formed by bending the light by 15° on the input protrusion, by reflection on the reflection sidewall providing further 30° of inclination, and by the bending of light on the output lens surface by another 15°.

[0022] Any appropriate angle can thus by provided by the combination of the optical parts of the cornering optical element. A single piece of material can thus provide all the processing of light needed to form the cornering illumination function.

[0023] The reflection sidewall can be inclined with respect to an optical axis of the output lens surface for increasing angle between the light and the optical axis by the reflection on the reflection sidewall. The sidewall can e.g., get closer to the axis in direction towards the front.

[0024] The output lens surface's optical axis can for example be angled at most 30°, advantageously at most 15°, more advantageously at most 10°, with respect to a longitudinal axis of a vehicle carrying the lamp. In other words, the cornering optical element is preferably oriented with its axis, which is the lens surface's axis, substantially in the back-to-front direction of the vehicle. This allows it to be aligned with other optical elements.

[0025] Preferably, the cornering optical element is the only optical element processing the light from the light source providing light into the input protrusion in the whole lamp. There are thus no further lens or reflectors in the way of the light. A cover lens can be provided in front of the output lens surface, but this cover lens then preferably has only mechanical function, without significantly affecting the light. The light from the at least one light source directed towards the input protrusion thus preferably only travels through the air around the cornering optical element, through the cornering optical element and through optional cover lens. This allows the cornering function to have higher efficiency.

[0026] The input protrusion can comprise a collimation input surface for decreasing divergence of light from the at least one light source. The shape of this surface can e.g., be provided by an optical modeling software. The collimation input surface can bend the light and / or reflect it, such that it travels towards the reflection sidewall as more parallel rays.

[0027] The output lens surface can comprise optical sub-elements for directing and / or homogenizing light which include one or more of: protrusions and / or recesses, graining, grooving, corrugation, micro-optical elements, division of the output lens surface into multiple mutually inclined sub-surfaces, teeth-shaped elements, or pillow-shaped elements.

[0028] Protrusions or recesses can be any irregularities on the inclined surface of the lightguide. They can scatter and diffuse light passing through. Protrusions extend outward from the surface, while recesses are indentations into the surface. These optical elements can help to break up the transmitted light rays and create a more uniform distribution of light output. They can have any sizes and shapes, such as cones, pyramids, grooves, ridges or random shapes. They can e.g., be molded during creation of the cornering optical element by providing complementary shape to a wall of the mold. Teeth-shaped elements can be a special case of protrusions and / or recesses and can be used to locally vary inclination of the surface.

[0029] Graining, i.e., imparting a fine, usually random, texture onto the inclined surface, helps with scattering light in different directions, thus increasing homogenization of the light passing through. The size and density of the grains can be adjusted to control the degree of light scattering. Grooves can be straight or curved and can have any shape and size of cross-section. They can be arranged next to each other in an orderly manner, but also randomly, they can cross each other, etc. Corrugation can be similar to forming smooth grooves or grooves and ridges.

[0030] Micro-optical elements are miniature optical structures designed to manipulate light at a small scale. For example, they can be elements smaller than 0.5 mm, preferably smaller than 0.2 mm or smaller than 0.1 mm. They can include micro lenses, prisms, or diffractive structures and can be used to homogenize the light and / or to direct it, i.e., adjust its orientation as needed for the cornering function. Micro-optical elements can be designed by a computer modelling software and they can be used for very significant processing of the light according to any specific needs or requirements without taking-up a significant amount of space.

[0031] The cornering optical element can have a polygonal cross-section along most of its length, wherein the reflection sidewall corresponds to one edge of the polygonal cross-section. The reflection sidewall can then be substantially flat, with clearly given boundaries. The cornering illumination beam can then also have clear, sharp boundaries.

[0032] Preferably, the lamp further comprises at least one further optical element for providing a further illumination function different from cornering function. The lamp then comprises at least one light source corresponding to the further optical element. The further illumination function is for providing a light beam which diverges less from a longitudinal axis of a vehicle carrying the lamp then a light beam of the cornering function. In other words, the further illumination function shines more to the front and less to the side when compared with the cornering function. The at least one light source corresponding to the cornering optical element and the at least one light source corresponding to the further optical element are both preferably oriented in the same direction.

[0033] The lamp with these two optical elements thus has two light sources with the same orientation, which can then e.g., by attached to the same light source carrier and can take up less space. The light from one source is directed to the side of the vehicle for providing the cornering function, and light from the other source is directed in front of the vehicle.

[0034] Preferably, the at least one light source corresponding to the cornering optical element and the at least one light source corresponding to the further optical element are both carried by one common flat printed circuit board. Both light sources, which provide mutually diverging illumination functions, are thus mounted together, can have the same power cable, the same heat sink etc.

[0035] Preferably, the cornering optical element and the further optical element are from a single piece of material. This again allows both illumination functions to be provided by a more compact lamp, which is easier or cheaper to manufacture.

[0036] The shortcomings of the solutions known in the prior art are to some extent also eliminated by a cornering optical element for the vehicle lamp described above. The element comprises an input protrusion, on its back side, for incoupling light from a light source; an output lens surface, on its front side, for outputting light for providing a cornering function; and a reflection sidewall extending between the front side and back side of the cornering optical element. The input protrusion, the output lens surface and the reflection sidewall are from a single piece of material and are configured for directing light from the light source towards the reflection sidewall of the cornering optical element by the input protrusion; and reflecting the light on the reflection sidewall towards the output lens surface.

[0037] The functioning of the cornering optical element and further optional features it can have are described above in relation to the lamp according to the invention.Description of drawings

[0038] A summary of the invention is further described by means of exemplary embodiments thereof, which are described with reference to the accompanying drawings, in which: Fig 1.Shows a schematic top view of a first embodiment of a vehicle lamp according to the present invention, where the lamp is a right cornering lamp illuminating the right side of the road and the drawing shows how an illustrative light ray gets bent and reflected by the lamp's cornering optical element. Fig 2.Shows a perspective front view of the cornering optical element shown in fig. 1. Fig 3.Shows a side view of the cornering optical element from fig. 2. Fig 4.Shows a schematic perspective view of a combined optical element from a second embodiment of the invention wherein this element comprises a cornering optical element and several further optical elements for providing several headlight illumination functions. Fig 5.Shows a front view of the combined optical element from fig. 4. Fig 6.Shows a rear view of the combined optical element from figs. 4 and 5. Fig 7.Schematically shows a side view of a lamp according to the second embodiment. Fig 8.Schematically shows light propagation through one of the further optical elements which provides illumination in front of the vehicle. Fig 9.Schematically shows light propagation through the cornering optical element which provides illumination on the side. Fig 10.Shows a schematic top view of an automobile provided with two lamps according to the second embodiment, wherein arrows mark directions of the cornering illumination function and a further illumination function. Exemplary Embodiments of the Invention

[0039] The invention will be further described by means of exemplary embodiments with reference to the respective drawings.

[0040] A first embodiment of the invention is shown in figs. 1 to 3. The vehicle lamp in this embodiment comprises a cornering optical element 2 and a PCB 11 with an LED light source 1. It further comprises standard lamp components (not shown) including a heat sink, wiring, casing 12 and cover lens. The lamp in this embodiment is a cornering lamp, it does not provide other illumination functions and is intended for installation next to a headlight. The cornering lamp can be controlled by a vehicle illumination control unit based on position of the steering wheel such that it is switched on whenever the steering wheel, and thus the front wheels, are angled more then a predetermined threshold, e.g. by more then 20° of the steering wheel.

[0041] The cornering optical element 2 is made from one block of PMMA and comprises a body 4 and a collimating input protrusion 3. The body 4 has a roughly cuboidal shape which slightly narrows towards its front side when viewed from above. It has a rectangular cross-section along most of its length. A back side of the body 4 is flat and is connected to the input protrusion 3. The front side is formed as an output lens surface 5 of the cornering optical element 2. The four sides of the body 4, two of which are rectangular and two of which are substantially trapezoidal, extend in the front-back direction which corresponds to an x-axis direction of an automobile provided with the lamp.

[0042] The output lens surface 5 is a freeform lens with a curved surface (see fig. 1 or 2) and with optical sub-elements 9, which in this embodiment are micro-optical elements designed for bending light and increasing homogeneity. The micro-optical elements have the form of grooves extending from top to bottom. The output lens surface 5 has an optical axis 7, illustrated in fig. 1, which is parallel with the x-axis. The optical axis 7 passes through the focal point of the lens surface 5 and through the center of the output lens surface 5. It does not pass through the LED light source 1.

[0043] The input protrusion 3 has roughly a conical shape, which has axis approximately parallel to the optical axis 7 of the output lens surface 5, and is truncated from the top such that it has a flat upper wall. The input protrusion 3 is connected to the back side of the body 4 off-center, such that it is closer to a left sidewall of the body 4. Walls of the input protrusion 3 are designed such that they reflect light, inputted into the input protrusion 3 through its rear base surface, towards the left sidewall of the body 4 at an angle sufficient for total internal reflection. Divergence of the light is decreased by this reflection on the walls of the input protrusion 3, i.e., a collimation of the light occurs. The surfaces of these walls are thus collimation input surfaces 8 of the cornering optical element 2. The left sidewall is then a reflection sidewall 6 which reflects the light towards the output lens surface 5.

[0044] The input protrusion 3 has a cavity on its rear base (see fig. 1) and the LED light source 1 is directed towards this cavity. The light from the LED thus enters the cornering optical element 2 through bottom and walls of this cavity. Some of the light travels directly to the reflection sidewall 6, most of the light is first reflected by the collimation input surfaces 8 forming outer surfaces of the input protrusion 3 and only then are directed towards the reflection sidewall 6. From the input protrusion 3, the light thus already travels more inclined than it was when outputted from the LED.

[0045] The reflection sidewall 6 is inclined with respect to the optical axis 7 - it gets closer to the optical axis 7 as it extends towards the front. The reflection on the reflection sidewall 6 thus increases the angle between the light and the optical axis 7. The reflected light then travels towards the output lens surface 5, where it is further bent by the lens surface 5 and its optical sub-elements 9. After passing through the output lens surface 5, the light is outside of the lamp and is inclined by approximately 60° angle α with respect to the optical axis 7 (see fig. 1).

[0046] Light rays forming the cornering optical function are not entirely parallel so this angle is not the same for all the light rays, but on average, the light rays are outputted from the cornering lamp at 60° angle such that they illuminate the area towards which the vehicle can be steered. The angle α can also be seen in fig. 10. The above-described processing of light in the cornering optical element 2 is depicted in fig. 9. Some stray light can occur in the lamp, which gets outputted in some other direction, but the vast majority of light gest outputted from the output lens surface 5 towards the side.

[0047] In this embodiment, the light is only processed by the cornering optical element 2, there are no further lens or reflectors. It was measured for this embodiment, that the absence of further lens, which would introduce two more boundaries PMMA-air, increases efficiency of the lamp by roughly 8 %, and the use of total internal reflection on the reflection sidewall 6, instead of a reflector with a reflective coating, increases the efficiency by roughly 15 %. At the same time, the lamp and its optical element extend in the front-rear direction of the vehicle they are mounted to, and can thus be placed directly next to other components, such as a headlight, without any dead space between them.

[0048] A second embodiment of the invention is a vehicle headlight and is shown in figs. 4 to 10. This headlight has several modules, seven in the shown embodiment, where each module has its own LED light source 1 and an optical element. All the optical elements are from a single piece of material - a combined optical element, as shown in figs. 4 to 8. The headlight further comprises a casing 12, wiring etc.

[0049] Each of the optical elements has analogous shape to the cornering optical element 2 from the first embodiment. Each has a collimating input protrusion 3 and a body 4 with an output lens surface 5 at the front. Referring to the drawings, the uppermost element is a cornering optical element 2, which has the same features as described above in the first embodiment. The four elements below the cornering optical element 2 form together a low beam illumination function. The lowermost two elements, form a high beam illumination function, when lit together with the low beam elements. Each of the elements has a different shape than other elements - they are individually designed by a computer simulation. Each of them thus directs light to a different part of the road, or area next to the road. The illumination patterns from different elements can however overlap each other, e.g., to create a low beam pattern on the road with light intensities as prescribed by regulations.

[0050] The combined optical element further comprises a flange for mounting to the casing 12 and comprises five conical centering pins.

[0051] The combined optical element thus includes a cornering optical element 2, which directs light in a direction 13 of the cornering function diverging by angle α from the x-axis, and it includes six further optical elements 10, which direct light in a direction 14 of further illumination functions substantially straight ahead of the vehicle (see fig. 10). All seven elements have their LEDs on one flat PCB 11 and are oriented in the x-axis direction.

[0052] Fig. 8 schematically shows how light is processed in a further optical element 10. It can be seen that a light beam from a light source 1 gets collimated by an input protrusion 3, travels through the element and then is further collimated and homogenized by an output lens surface 5. Optical axis 7 of this element passes through the corresponding LED and the light beam outputted by the element is symmetrical with respect to the optical axis 7.

[0053] A third embodiment of the invention is the cornering optical element 2, as described in the first embodiment, by itself, i.e., without the other components of the lamp.Alternative embodiments

[0054] In further embodiments, the number of further optical elements 10, their shape, function etc. can be different. The angle α can also have a different value, e.g. between 15° and 75°, preferably between 45° and 75°. The optical axis 7 of the cornering optical element 2 and / or of the further optical element(s) 10 does not have to be parallel to the x-axis, but can be inclined, e.g., by up to 15° relative to the axis.

[0055] In the shown embodiment, the LED of the cornering optical element 2 is outside of the cavity in the input protrusion 3, but alternatively, the light source 1 can extend into the cavity.

[0056] The reflection sidewall 6 can be curved in some embodiments and / or composed of multiple mutually inclined surfaces. In some embodiments, one or more of the optical elements can have multiple corresponding light sources 1. The optical elements, including the cornering optical element 2, can have a different shape of cross-section, such as circular, oval, hexagonal etc. For a cornering optical element 2 with at least partially round cross-section, the reflection sidewall 6 can be made substantially flat to ensure required directing of the light.

[0057] In some embodiments, the cornering optical element 2 can be separated from the further optical element 10. The light source 1 corresponding to the cornering function can be inclined relative to the further light sources 1, e.g., by up to 45°. The shape of the cornering optical element 2 with the reflection sidewall 6 increases this inclination to provide the angle α needed for the cornering function. The cornering optical element 2 in such embodiment allows for having a less inclined cornering light source 1, than what would be needed if the inclination of the light source 1 should correspond to the angle α.Reference list

[0058] 1.light source 2.cornering optical element 3.input protrusion 4.body 5.lens surface 6.reflection sidewall 7.optical axis 8.collimation input surface 9.optical sub-elements 10.further optical element 11.printed circuit board 12.casing 13.direction of cornering function 14.direction of further function

Examples

first embodiment

[0040]the invention is shown in figs. 1 to 3. The vehicle lamp in this embodiment comprises a cornering optical element 2 and a PCB 11 with an LED light source 1. It further comprises standard lamp components (not shown) including a heat sink, wiring, casing 12 and cover lens. The lamp in this embodiment is a cornering lamp, it does not provide other illumination functions and is intended for installation next to a headlight. The cornering lamp can be controlled by a vehicle illumination control unit based on position of the steering wheel such that it is switched on whenever the steering wheel, and thus the front wheels, are angled more then a predetermined threshold, e.g. by more then 20° of the steering wheel.

[0041]The cornering optical element 2 is made from one block of PMMA and comprises a body 4 and a collimating input protrusion 3. The body 4 has a roughly cuboidal shape which slightly narrows towards its front side when viewed from above. It has a rectangular cross-section ...

second embodiment

[0048]the invention is a vehicle headlight and is shown in figs. 4 to 10. This headlight has several modules, seven in the shown embodiment, where each module has its own LED light source 1 and an optical element. All the optical elements are from a single piece of material - a combined optical element, as shown in figs. 4 to 8. The headlight further comprises a casing 12, wiring etc.

[0049]Each of the optical elements has analogous shape to the cornering optical element 2 from the first embodiment. Each has a collimating input protrusion 3 and a body 4 with an output lens surface 5 at the front. Referring to the drawings, the uppermost element is a cornering optical element 2, which has the same features as described above in the first embodiment. The four elements below the cornering optical element 2 form together a low beam illumination function. The lowermost two elements, form a high beam illumination function, when lit together with the low beam elements. Each of the elements ...

Technical field

[0001] The present invention relates to headlights for vehicles, more specifically to cornering illumination function and an optical element which can provide this function.Background of the Invention

[0002] A cornering illumination function is a known function of automobile headlights. It provides a laterally inclined beam of light which is activated when the automobile is turning in order to provide more light in the area towards the vehicle is being turned. While standard headlight illumination functions, such as high beam, low beam, daytime running light etc., are generally oriented to the front, to illuminate the road ahead or to be visible for incoming drivers, the cornering function is significantly inclined to one side. This allows drivers to e.g., spot any obstacles they could collide with during steering.

[0003] The cornering function thus improves illumination on curves or intersections, and helps drivers see the road's layout, pedestrians, and potential obstacles earlier. There are two primary types of cornering headlights: static and dynamic. Static cornering lights are fixedly inclined to one side and are turned on e.g., based on angle of the steering wheel. Dynamic cornering lights are provided with actuators and their inclination can thus be varied, e.g., based on how much the wheels are turned.

[0004] An example of a headlight with a dynamic cornering function is described in document US6341884B1. A movable reflector is provided in this document which can direct a beam of light to one side to provide the cornering function.

[0005] One disadvantage of known cornering lamps is their complexity and cost. Dynamic cornering requires actuators, control units and space around the light for its movement. Static cornering lamps also require a significant amount of space, since they are inclined relative to other illumination modules or components, the require individual PCBs since their light sources also have to be inclined, or they require reflectors to incline the light, which again requires space, increases cost and also decreases illumination efficiency.

[0006] It would therefore be advantageous to provide a lamp with a cornering illumination function, which could have less parts, higher efficiency, could take up less space and / or could be cheaper to manufacture.Summary of the Invention

[0007] The shortcomings of the solutions known in the prior art are to some extent eliminated by a vehicle lamp with cornering function comprising at least one light source, and a cornering optical element. The cornering optical element comprises a body, and an input protrusion, which is on a back side of the body. The input protrusion serves for coupling light from at least one light source into the cornering optical element. This at least one light source can thus be direction towards the protrusion and the light enters the cornering optical element through the protrusion.

[0008] The body of the cornering optical element further comprises an output lens surface, on a front side of the body. The lens surface serves for outputting light from the optical element for providing the cornering function. The front side is closer to the area in front of the lamp, in a standard direction of travel of a vehicle with the lamp. The direction of travel corresponds to a longitudinal axis of the vehicle and is usually marked as x-axis. The back side is on the opposite side of the body, i.e., it is closer to the passenger area.

[0009] The cornering optical element further comprises a reflection sidewall extending at least part of the way between the front side and the back side of the body. The input protrusion, the output lens surface and the reflection sidewall are from a single piece of material and are configured, especially by their shape, orientation and arrangement relative to each other and to the at least one light source, for: Directing light from the at least one light source towards the reflection sidewall of the cornering optical element by the input protrusion. In other words, the light enters the optical element, is processed by the input protrusion and sent towards the reflection sidewall. Reflecting the light on the reflection sidewall towards the output lens surface. Preferably this reflection is the result of a total internal reflection, but it is also possible to provide a reflective coating to the reflection sidewall. The light processed by the cornering optical element is thus reflected on one sidewall of the element.

[0010] Most of the light provided by the at least one light source is thus directed towards one side of the element - the side with the reflection sidewall. Preferably, it is a vast majority of the light, e.g., at least 80% or at least 90% of light which enters the cornering optical element is sent towards the sidewall. The input protrusion is thus adapted to direct light towards one side (to the left or to the right), e.g., to make the whole inputted light beam more inclined relative to an optical axis or the x-axis of the vehicle carrying the lamp.

[0011] A cornering illumination function is standardly inclined relative to other illumination functions. It is intended for illumination of areas not directly in front of the vehicle, especially during turning. It can for example by inclined by at least 45° relative to the x-axis when viewed from above. The reflection by the reflection sidewall, preferably together with light directing by the input protrusion and / or the lens surface, can be used in the present invention to incline the light as needed for the cornering function. A need for further optical elements for changing the inclination of this light can thus be removed by the invention.

[0012] The fact that the inclination is at least partially achieved by the reflection sidewall, which is in the same piece of material as the output lens surface, also helps achieving the desired inclination in a smaller space, since there is no air-to-lens boundary between the reflection sidewall and the output lens surface. If the reflector was separated from the lens, there would be at least one further optical boundary between them which would bend the light closer to the optical axis and thus decrease the angle.

[0013] The output lens surface can form any type of lens - it can be a smooth curved surface such as spherical, parabolical or freeform lens, it can be Fresnel-type lens made from a number of distinct subsurfaces, it can comprise micro-optical elements etc. It is designed, especially by a computer simulation, to bend the light into an appropriate direction for the cornering function, and it can increase the homogeneity of the light. The reflection sidewall can be planar or curved, flat or provided with optical sub-elements, it can be a single surface or multiple surfaces, etc. The reflection sidewall can also be provided by an optical simulation software. The simulation can provide a shape of the lens surface and / or the reflection sidewall and / or the input protrusion based on parameters such as type and position of the light source, material of the element, desired direction of outputted cornering beam, shape and position of the lens surface and / or the reflection sidewall and / or the input protrusion, etc.

[0014] The input protrusion can have any shape, especially an elongated substantially cylindrical or conical shape. It can be located substantially in the center of the back side, or it can be closer to one side. It can especially be closer to the side of the optical element where the reflecting sidewall is located, or closer to the opposite side. It can include one or more entry surfaces for the light. The input protrusion's side surface(s) can serve for entering of the light into the optical element, and / or they can serve for reflection of light towards the reflection sidewall. The input protrusion can include a cavity and the at least one light source can be at least partially located in this cavity.

[0015] The material of the cornering optical element can be at least partially transparent or translucent. It can be glass or a polymer, such as polycarbonate, PMMA or silicone.

[0016] The invention can provide the cornering function in a more compact lamp when compared to a lamp where the reflection on a reflection sidewall would not occur. Due to the relatively large angle of the cornering function relative to the x-axis and the direction of travel (for example, 60° is required by regulations in some countries), a lamp for providing the illumination without further optical elements and without reflection on a sidewall would need to be very wide to provide enough space for propagation of light from an entrance into the optical element to an exit for the light from the element.

[0017] Since the use of the reflection on the sidewall with the input protrusion and lens surface, which are all from a single piece of material, can eliminate a need for further optical elements, the invention can also provide the cornering function more efficiently than known lamps. When the light is processed in a single piece of material, there are fewer optical boundaries the light needs to cross and thus there are fewer places where light loss can occur.

[0018] Preferably, the cornering optical element does not contain any optical boundaries which the light would have to cross during its travel through the optical element, except at the input protrusion and the output lens surface. I.e., there are preferably no holes or cut-outs in the optical element such that the light would leave the optical element and then enter it again. Such a boundary would especially be boundary between the material of the cornering optical element and air. Another such boundary might be between the material of the element and a reflective material provided on the reflection wall.

[0019] Preferably, a light beam outputted by the light source providing light into the input protrusion, before this light enters the cornering optical element, is angled with respect to a light beam outputted from the cornering optical element by at least 15°. In other words, the cornering optical element preferably increases inclination of inputted light by at least 15°. This inclination can be measured from above, when the lamp is installed in a vehicle. Preferably, this angle is at least 30°, more advantageously, it can be at least 40° or at least 50°. The angle of a beam of light can be measured from an axis of the beam of light - it can be a main propagation direction of the light forming the beam, e.g., given as an average direction over all the light forming the beam.

[0020] This angle allows the lamp to provide the cornering illumination function with a light source oriented substantially towards the front. The light source can thus e.g., be placed in the same plane as other light sources from the lamp for further optical functions. The lamp can also be more compact since the cornering components can be aligned with components for the further optical functions, with less space in-between.

[0021] The angle of at least 15° between the light beam outputted by the light source providing light into the input protrusion and the light beam outputted from the cornering optical element can be partially provided by bending of light by the input protrusion and can be partially provided by bending of light by the output lens surface. The reflection side wall can also influence this angle. For example, the angle can be 60°, such that the cornering light beam is directed 60° towards the left or towards the right, while the light source is oriented directly forward. The 60° angle can e.g., be formed by bending the light by 15° on the input protrusion, by reflection on the reflection sidewall providing further 30° of inclination, and by the bending of light on the output lens surface by another 15°.

[0022] Any appropriate angle can thus by provided by the combination of the optical parts of the cornering optical element. A single piece of material can thus provide all the processing of light needed to form the cornering illumination function.

[0023] The reflection sidewall can be inclined with respect to an optical axis of the output lens surface for increasing angle between the light and the optical axis by the reflection on the reflection sidewall. The sidewall can e.g., get closer to the axis in direction towards the front.

[0024] The output lens surface's optical axis can for example be angled at most 30°, advantageously at most 15°, more advantageously at most 10°, with respect to a longitudinal axis of a vehicle carrying the lamp. In other words, the cornering optical element is preferably oriented with its axis, which is the lens surface's axis, substantially in the back-to-front direction of the vehicle. This allows it to be aligned with other optical elements.

[0025] Preferably, the cornering optical element is the only optical element processing the light from the light source providing light into the input protrusion in the whole lamp. There are thus no further lens or reflectors in the way of the light. A cover lens can be provided in front of the output lens surface, but this cover lens then preferably has only mechanical function, without significantly affecting the light. The light from the at least one light source directed towards the input protrusion thus preferably only travels through the air around the cornering optical element, through the cornering optical element and through optional cover lens. This allows the cornering function to have higher efficiency.

[0026] The input protrusion can comprise a collimation input surface for decreasing divergence of light from the at least one light source. The shape of this surface can e.g., be provided by an optical modeling software. The collimation input surface can bend the light and / or reflect it, such that it travels towards the reflection sidewall as more parallel rays.

[0027] The output lens surface can comprise optical sub-elements for directing and / or homogenizing light which include one or more of: protrusions and / or recesses, graining, grooving, corrugation, micro-optical elements, division of the output lens surface into multiple mutually inclined sub-surfaces, teeth-shaped elements, or pillow-shaped elements.

[0028] Protrusions or recesses can be any irregularities on the inclined surface of the lightguide. They can scatter and diffuse light passing through. Protrusions extend outward from the surface, while recesses are indentations into the surface. These optical elements can help to break up the transmitted light rays and create a more uniform distribution of light output. They can have any sizes and shapes, such as cones, pyramids, grooves, ridges or random shapes. They can e.g., be molded during creation of the cornering optical element by providing complementary shape to a wall of the mold. Teeth-shaped elements can be a special case of protrusions and / or recesses and can be used to locally vary inclination of the surface.

[0029] Graining, i.e., imparting a fine, usually random, texture onto the inclined surface, helps with scattering light in different directions, thus increasing homogenization of the light passing through. The size and density of the grains can be adjusted to control the degree of light scattering. Grooves can be straight or curved and can have any shape and size of cross-section. They can be arranged next to each other in an orderly manner, but also randomly, they can cross each other, etc. Corrugation can be similar to forming smooth grooves or grooves and ridges.

[0030] Micro-optical elements are miniature optical structures designed to manipulate light at a small scale. For example, they can be elements smaller than 0.5 mm, preferably smaller than 0.2 mm or smaller than 0.1 mm. They can include micro lenses, prisms, or diffractive structures and can be used to homogenize the light and / or to direct it, i.e., adjust its orientation as needed for the cornering function. Micro-optical elements can be designed by a computer modelling software and they can be used for very significant processing of the light according to any specific needs or requirements without taking-up a significant amount of space.

[0031] The cornering optical element can have a polygonal cross-section along most of its length, wherein the reflection sidewall corresponds to one edge of the polygonal cross-section. The reflection sidewall can then be substantially flat, with clearly given boundaries. The cornering illumination beam can then also have clear, sharp boundaries.

[0032] Preferably, the lamp further comprises at least one further optical element for providing a further illumination function different from cornering function. The lamp then comprises at least one light source corresponding to the further optical element. The further illumination function is for providing a light beam which diverges less from a longitudinal axis of a vehicle carrying the lamp then a light beam of the cornering function. In other words, the further illumination function shines more to the front and less to the side when compared with the cornering function. The at least one light source corresponding to the cornering optical element and the at least one light source corresponding to the further optical element are both preferably oriented in the same direction.

[0033] The lamp with these two optical elements thus has two light sources with the same orientation, which can then e.g., by attached to the same light source carrier and can take up less space. The light from one source is directed to the side of the vehicle for providing the cornering function, and light from the other source is directed in front of the vehicle.

[0034] Preferably, the at least one light source corresponding to the cornering optical element and the at least one light source corresponding to the further optical element are both carried by one common flat printed circuit board. Both light sources, which provide mutually diverging illumination functions, are thus mounted together, can have the same power cable, the same heat sink etc.

[0035] Preferably, the cornering optical element and the further optical element are from a single piece of material. This again allows both illumination functions to be provided by a more compact lamp, which is easier or cheaper to manufacture.

[0036] The shortcomings of the solutions known in the prior art are to some extent also eliminated by a cornering optical element for the vehicle lamp described above. The element comprises an input protrusion, on its back side, for incoupling light from a light source; an output lens surface, on its front side, for outputting light for providing a cornering function; and a reflection sidewall extending between the front side and back side of the cornering optical element. The input protrusion, the output lens surface and the reflection sidewall are from a single piece of material and are configured for directing light from the light source towards the reflection sidewall of the cornering optical element by the input protrusion; and reflecting the light on the reflection sidewall towards the output lens surface.

[0037] The functioning of the cornering optical element and further optional features it can have are described above in relation to the lamp according to the invention.Description of drawings

[0038] A summary of the invention is further described by means of exemplary embodiments thereof, which are described with reference to the accompanying drawings, in which: Fig 1.Shows a schematic top view of a first embodiment of a vehicle lamp according to the present invention, where the lamp is a right cornering lamp illuminating the right side of the road and the drawing shows how an illustrative light ray gets bent and reflected by the lamp's cornering optical element. Fig 2.Shows a perspective front view of the cornering optical element shown in fig. 1. Fig 3.Shows a side view of the cornering optical element from fig. 2. Fig 4.Shows a schematic perspective view of a combined optical element from a second embodiment of the invention wherein this element comprises a cornering optical element and several further optical elements for providing several headlight illumination functions. Fig 5.Shows a front view of the combined optical element from fig. 4. Fig 6.Shows a rear view of the combined optical element from figs. 4 and 5. Fig 7.Schematically shows a side view of a lamp according to the second embodiment. Fig 8.Schematically shows light propagation through one of the further optical elements which provides illumination in front of the vehicle. Fig 9.Schematically shows light propagation through the cornering optical element which provides illumination on the side. Fig 10.Shows a schematic top view of an automobile provided with two lamps according to the second embodiment, wherein arrows mark directions of the cornering illumination function and a further illumination function. Exemplary Embodiments of the Invention

[0039] The invention will be further described by means of exemplary embodiments with reference to the respective drawings.

[0040] A first embodiment of the invention is shown in figs. 1 to 3. The vehicle lamp in this embodiment comprises a cornering optical element 2 and a PCB 11 with an LED light source 1. It further comprises standard lamp components (not shown) including a heat sink, wiring, casing 12 and cover lens. The lamp in this embodiment is a cornering lamp, it does not provide other illumination functions and is intended for installation next to a headlight. The cornering lamp can be controlled by a vehicle illumination control unit based on position of the steering wheel such that it is switched on whenever the steering wheel, and thus the front wheels, are angled more then a predetermined threshold, e.g. by more then 20° of the steering wheel.

[0041] The cornering optical element 2 is made from one block of PMMA and comprises a body 4 and a collimating input protrusion 3. The body 4 has a roughly cuboidal shape which slightly narrows towards its front side when viewed from above. It has a rectangular cross-section along most of its length. A back side of the body 4 is flat and is connected to the input protrusion 3. The front side is formed as an output lens surface 5 of the cornering optical element 2. The four sides of the body 4, two of which are rectangular and two of which are substantially trapezoidal, extend in the front-back direction which corresponds to an x-axis direction of an automobile provided with the lamp.

[0042] The output lens surface 5 is a freeform lens with a curved surface (see fig. 1 or 2) and with optical sub-elements 9, which in this embodiment are micro-optical elements designed for bending light and increasing homogeneity. The micro-optical elements have the form of grooves extending from top to bottom. The output lens surface 5 has an optical axis 7, illustrated in fig. 1, which is parallel with the x-axis. The optical axis 7 passes through the focal point of the lens surface 5 and through the center of the output lens surface 5. It does not pass through the LED light source 1.

[0043] The input protrusion 3 has roughly a conical shape, which has axis approximately parallel to the optical axis 7 of the output lens surface 5, and is truncated from the top such that it has a flat upper wall. The input protrusion 3 is connected to the back side of the body 4 off-center, such that it is closer to a left sidewall of the body 4. Walls of the input protrusion 3 are designed such that they reflect light, inputted into the input protrusion 3 through its rear base surface, towards the left sidewall of the body 4 at an angle sufficient for total internal reflection. Divergence of the light is decreased by this reflection on the walls of the input protrusion 3, i.e., a collimation of the light occurs. The surfaces of these walls are thus collimation input surfaces 8 of the cornering optical element 2. The left sidewall is then a reflection sidewall 6 which reflects the light towards the output lens surface 5.

[0044] The input protrusion 3 has a cavity on its rear base (see fig. 1) and the LED light source 1 is directed towards this cavity. The light from the LED thus enters the cornering optical element 2 through bottom and walls of this cavity. Some of the light travels directly to the reflection sidewall 6, most of the light is first reflected by the collimation input surfaces 8 forming outer surfaces of the input protrusion 3 and only then are directed towards the reflection sidewall 6. From the input protrusion 3, the light thus already travels more inclined than it was when outputted from the LED.

[0045] The reflection sidewall 6 is inclined with respect to the optical axis 7 - it gets closer to the optical axis 7 as it extends towards the front. The reflection on the reflection sidewall 6 thus increases the angle between the light and the optical axis 7. The reflected light then travels towards the output lens surface 5, where it is further bent by the lens surface 5 and its optical sub-elements 9. After passing through the output lens surface 5, the light is outside of the lamp and is inclined by approximately 60° angle α with respect to the optical axis 7 (see fig. 1).

[0046] Light rays forming the cornering optical function are not entirely parallel so this angle is not the same for all the light rays, but on average, the light rays are outputted from the cornering lamp at 60° angle such that they illuminate the area towards which the vehicle can be steered. The angle α can also be seen in fig. 10. The above-described processing of light in the cornering optical element 2 is depicted in fig. 9. Some stray light can occur in the lamp, which gets outputted in some other direction, but the vast majority of light gest outputted from the output lens surface 5 towards the side.

[0047] In this embodiment, the light is only processed by the cornering optical element 2, there are no further lens or reflectors. It was measured for this embodiment, that the absence of further lens, which would introduce two more boundaries PMMA-air, increases efficiency of the lamp by roughly 8 %, and the use of total internal reflection on the reflection sidewall 6, instead of a reflector with a reflective coating, increases the efficiency by roughly 15 %. At the same time, the lamp and its optical element extend in the front-rear direction of the vehicle they are mounted to, and can thus be placed directly next to other components, such as a headlight, without any dead space between them.

[0048] A second embodiment of the invention is a vehicle headlight and is shown in figs. 4 to 10. This headlight has several modules, seven in the shown embodiment, where each module has its own LED light source 1 and an optical element. All the optical elements are from a single piece of material - a combined optical element, as shown in figs. 4 to 8. The headlight further comprises a casing 12, wiring etc.

[0049] Each of the optical elements has analogous shape to the cornering optical element 2 from the first embodiment. Each has a collimating input protrusion 3 and a body 4 with an output lens surface 5 at the front. Referring to the drawings, the uppermost element is a cornering optical element 2, which has the same features as described above in the first embodiment. The four elements below the cornering optical element 2 form together a low beam illumination function. The lowermost two elements, form a high beam illumination function, when lit together with the low beam elements. Each of the elements has a different shape than other elements - they are individually designed by a computer simulation. Each of them thus directs light to a different part of the road, or area next to the road. The illumination patterns from different elements can however overlap each other, e.g., to create a low beam pattern on the road with light intensities as prescribed by regulations.

[0050] The combined optical element further comprises a flange for mounting to the casing 12 and comprises five conical centering pins.

[0051] The combined optical element thus includes a cornering optical element 2, which directs light in a direction 13 of the cornering function diverging by angle α from the x-axis, and it includes six further optical elements 10, which direct light in a direction 14 of further illumination functions substantially straight ahead of the vehicle (see fig. 10). All seven elements have their LEDs on one flat PCB 11 and are oriented in the x-axis direction.

[0052] Fig. 8 schematically shows how light is processed in a further optical element 10. It can be seen that a light beam from a light source 1 gets collimated by an input protrusion 3, travels through the element and then is further collimated and homogenized by an output lens surface 5. Optical axis 7 of this element passes through the corresponding LED and the light beam outputted by the element is symmetrical with respect to the optical axis 7.

[0053] A third embodiment of the invention is the cornering optical element 2, as described in the first embodiment, by itself, i.e., without the other components of the lamp.Alternative embodiments

[0054] In further embodiments, the number of further optical elements 10, their shape, function etc. can be different. The angle α can also have a different value, e.g. between 15° and 75°, preferably between 45° and 75°. The optical axis 7 of the cornering optical element 2 and / or of the further optical element(s) 10 does not have to be parallel to the x-axis, but can be inclined, e.g., by up to 15° relative to the axis.

[0055] In the shown embodiment, the LED of the cornering optical element 2 is outside of the cavity in the input protrusion 3, but alternatively, the light source 1 can extend into the cavity.

[0056] The reflection sidewall 6 can be curved in some embodiments and / or composed of multiple mutually inclined surfaces. In some embodiments, one or more of the optical elements can have multiple corresponding light sources 1. The optical elements, including the cornering optical element 2, can have a different shape of cross-section, such as circular, oval, hexagonal etc. For a cornering optical element 2 with at least partially round cross-section, the reflection sidewall 6 can be made substantially flat to ensure required directing of the light.

[0057] In some embodiments, the cornering optical element 2 can be separated from the further optical element 10. The light source 1 corresponding to the cornering function can be inclined relative to the further light sources 1, e.g., by up to 45°. The shape of the cornering optical element 2 with the reflection sidewall 6 increases this inclination to provide the angle α needed for the cornering function. The cornering optical element 2 in such embodiment allows for having a less inclined cornering light source 1, than what would be needed if the inclination of the light source 1 should correspond to the angle α.Reference list

[0058] 1.light source 2.cornering optical element 3.input protrusion 4.body 5.lens surface 6.reflection sidewall 7.optical axis 8.collimation input surface 9.optical sub-elements 10.further optical element 11.printed circuit board 12.casing 13.direction of cornering function 14.direction of further function

Examples

first embodiment

[0040]the invention is shown in figs. 1 to 3. The vehicle lamp in this embodiment comprises a cornering optical element 2 and a PCB 11 with an LED light source 1. It further comprises standard lamp components (not shown) including a heat sink, wiring, casing 12 and cover lens. The lamp in this embodiment is a cornering lamp, it does not provide other illumination functions and is intended for installation next to a headlight. The cornering lamp can be controlled by a vehicle illumination control unit based on position of the steering wheel such that it is switched on whenever the steering wheel, and thus the front wheels, are angled more then a predetermined threshold, e.g. by more then 20° of the steering wheel.

[0041]The cornering optical element 2 is made from one block of PMMA and comprises a body 4 and a collimating input protrusion 3. The body 4 has a roughly cuboidal shape which slightly narrows towards its front side when viewed from above. It has a rectangular cross-section ...

second embodiment

[0048]the invention is a vehicle headlight and is shown in figs. 4 to 10. This headlight has several modules, seven in the shown embodiment, where each module has its own LED light source 1 and an optical element. All the optical elements are from a single piece of material - a combined optical element, as shown in figs. 4 to 8. The headlight further comprises a casing 12, wiring etc.

[0049]Each of the optical elements has analogous shape to the cornering optical element 2 from the first embodiment. Each has a collimating input protrusion 3 and a body 4 with an output lens surface 5 at the front. Referring to the drawings, the uppermost element is a cornering optical element 2, which has the same features as described above in the first embodiment. The four elements below the cornering optical element 2 form together a low beam illumination function. The lowermost two elements, form a high beam illumination function, when lit together with the low beam elements. Each of the elements ...

Claims

1. Vehicle lamp with cornering function comprising at least one light source (1), and a cornering optical element (2) characterized in that the cornering optical element (2) comprises • an input protrusion (3), on a back side of a body (4) of the cornering optical element (2), for coupling light from at least one light source (1) into the cornering optical element (2), • an output lens surface (5), on a front side of the body (4) of the cornering optical element (2), for outputting light for providing the cornering function, and • a reflection sidewall (6) extending between the front side and the back side of the body (4) of the cornering optical element (2), wherein the input protrusion (3), the output lens surface (5) and the reflection sidewall (6) are from a single piece of material and are configured for • directing light from the at least one light source (1) towards the reflection sidewall (6) of the cornering optical element (2) by the input protrusion (3), and • reflecting the light on the reflection sidewall (6) towards the output lens surface (5).

2. The vehicle lamp according to claim 1 wherein a light beam outputted by the light source (1) providing light into the input protrusion (3), before this light enters the cornering optical element (2), is angled relative to a light beam outputted from the cornering optical element (2) by at least 15°.

3. The vehicle lamp according to claim 2 wherein the angle of at least 15° between the light beam outputted by the light source (1) providing light into the input protrusion (3) and the light beam outputted from the cornering optical element (2) is partially provided by bending of light by the input protrusion (3) and is partially provided by bending of light by the output lens surface (5).

4. The vehicle lamp according to any preceding claim wherein the reflection sidewall (6) is inclined with respect to an optical axis (7) of the output lens surface (5) for increasing angle between the light and the optical axis (7) by the reflection on the reflection sidewall (6).

5. The vehicle lamp according to any preceding claim wherein the output lens surface's (5) optical axis (7) is angled at most 30° with respect to a longitudinal axis of a vehicle carrying the lamp.

6. The vehicle lamp according to any preceding claim wherein the cornering optical element (2) is the only optical element processing the light from the light source (1) providing light into the input protrusion (3) in the whole lamp.

7. The vehicle lamp according to any preceding claim wherein the input protrusion (3) comprises a collimation input surface (8) for decreasing divergence of light from the at least one light source (1).

8. The vehicle lamp according to any preceding claim wherein the output lens surface (5) comprises optical sub-elements (9) for directing and / or homogenizing light which include one or more of: protrusions and / or recesses, graining, grooving, corrugation, micro-optical elements, division of the output lens surface (5) into multiple mutually inclined sub-surfaces, teeth-shaped elements, or pillow-shaped elements.

9. The vehicle lamp according to any preceding claim wherein the cornering optical element (2) has a polygonal cross-section along most of its length, wherein the reflection sidewall (6) corresponds to one edge of the polygonal cross-section.

10. The vehicle lamp according to any preceding claim wherein the lamp further comprises at least one further optical element (10) for providing a further illumination function different from cornering function, wherein the lamp comprises at least one light source (1) corresponding to the further optical element (10), wherein the further illumination function is for providing a light beam which diverges less from a longitudinal axis of a vehicle carrying the lamp then a light beam of the cornering function, wherein the at least one light source (1) corresponding to the cornering optical element (2) and the at least one light source (1) corresponding to the further optical element (10) are both oriented in the same direction.

11. The vehicle lamp according to claim 10 wherein the at least one light source (1) corresponding to the cornering optical element (2) and the at least one light source (1) corresponding to the further optical element (10) are both carried by one common flat printed circuit board (11).

12. The vehicle lamp according to any one of claims 10 to 11 wherein the cornering optical element (2) and the further optical element (10) are from a single piece of material.

13. A cornering optical element (2) for the vehicle lamp according to any preceding claim characterized in that it comprises • an input protrusion (3), on its back side, for incoupling light from a light source (1), • an output lens surface (5), on its front side, for outputting light for providing a cornering function, and • a reflection sidewall (6) extending between the front side and back side of the cornering optical element (2), wherein the input protrusion (3), the output lens surface (5) and the reflection sidewall (6) are from a single piece of material and are configured for • directing light from the light source (1) towards the reflection sidewall (6) of the cornering optical element (2) by the input protrusion (3), and • reflecting the light on the reflection sidewall (6) towards the output lens surface (5).

Images