GB2550010A

GB2550010A - Headlamp adaptor

Info

Publication number: GB2550010A
Application number: GB1700634.7A
Authority: GB
Inventors: Ivor Harper Paul
Original assignee: Individual
Current assignee: Individual
Priority date: 2016-05-03
Filing date: 2017-01-13
Publication date: 2017-11-08
Anticipated expiration: 2037-01-13
Also published as: GB201607674D0; GB201700634D0; GB2550009A; GB2550009B; GB201700619D0; GB2550010B

Abstract

A headlamp adaptor for attachment to the headlamp of a motor vehicle is positionable on a cover 501 of the headlamp to intercept a portion of the headlamp beam directed to the near side of the road and modify selected wavelengths thereof. A coating may be provided on the surface of the adapter to modify selected wavelengths of light passing through the adapter, which may be made of plastic material that has had a dye added during manufacture.

Description

HEADLAMP ADAPTOR

This invention relates to a headlamp adaptor for changing the effect of a vehicle headlamp beam, for example to provide for the vehicle to be legally driven in a country where cars drive on the opposite side of the road, and reduce glare.

Headlights are an essential component of motorised vehicles, providing the means for other road users to recognise that a motorised vehicle is on the road, for example to track its progress and modify their behaviour to ensure the safety of all concerned, and also providing means for the motorised vehicle driver to see the road, and any hazards, ahead.

Generally such headlamps provide three categories of illumination: sidelights to indicate the presence of the vehicle, dipped beam to illuminate the road in front of, and to the side of, the vehicle to assist the driver, for example so that the driver can see the way ahead and also attributes of the side of the road, such as road signs positioned thereon, cyclists or pedestrians, and main beam to provide additional illumination for the driver.

Regulations set out the particular requirements for headlamps. In addition, in February 2011 the EU added to present regulations mandating that vehicles should have Daytime Running Lights (DRL) in an effort to improve road safety so that vehicles could always be clearly seen: consequently vehicles may potentially emit headlamp light at all times when on the road.

Headlamp light, while being helpful in the ways described, does have wide ranging impacts in other ways. For example, in modem headlamps the dipped beam brightness, even when aligned in accordance with regulations, can be sufficiently bright to dazzle other road users, and this can be a particular problem in cities or suburban areas. In addition, those who drive for a living such as taxi drivers, bus or HGV drivers, ambulance or police drivers, as well as other drivers, cyclists, or pedestrians, can be adversely affected by the brightness of even the dipped beam settings of many modem headlamps.

Historically vehicle headlamps have been fit for purpose, providing headlamp light sufficient to alert other road users without creating a hazard themselves. A study carried out in Japan in 2003 recommended that vehicle headlamp light, for example DRL headlamp lights, should provide 200 candelas of illumination. The EU initially proposed an intensity of 400 candelas for DRL but following negotiation with vehicle manufacturers increased this to 1200 candelas. However recently vehicle manufacturers have been seeking to ‘add value’ to their vehicles by providing them with Bi-Xenon High intensity Discharge (HID) headlights, Light Emitting Diode (LED) headlights, Laser or other headlights which often provide light of the order of 2500 candelas or more.

Historically headlamps illuminated the road ahead and to the side of the vehicle with an illumination pattern including a ‘kick-up’ portion to provide drivers with maximum information about the road conditions affecting the immediate part of their journey. Partly in an effort to manage the additional light intensity provided by modern headlamps, many vehicle manufacturers provide headlamps which illuminate a specific area in front of the vehicle so that no light shines above a horizon position as seen in figure 1 (a), where the margin between illuminated and non-illuminated is narrow. Such an arrangement is directed to avoid glare from the vehicle headlamp light dazzling drivers in front of the vehicle. To provide capability for vehicles to be driven in countries where vehicles drive on the opposite side of the road, so that the vehicle headlamp light does not dazzle oncoming drivers, and to comply with regulations in those countries, adaptors are available for all headlamp types to modify the beam as required.

However headlamp arrangements are predicated on a vehicle travelling on a flat surface whereas roads include bumps, hills and bends, all of which may cause the headlamp beam to rise and shine into the eyes of drivers in oncoming traffic or vehicles in front. Thus all types of headlamps in use on the roads have the capacity to dazzle the drivers of vehicles in front, oncoming vehicles, and also pedestrians or other road users. As well as affecting the manner in which the dazzled behave, impacting for example the standard of driving of drivers, and the ability to negotiate the roads for other road users, such dazzle also impacts their eye health.

For those whose work involves significant amounts of driving, such as lorry, bus or taxi drivers, or ambulance, police, fire workers or others, it is impossible to avoid the problems, in particular eye health problems, that encountering such dazzle presents.

In addition other road users, such as pedestrians, including children and the elderly or pedal cyclists, will also suffer from the impact of dazzle, for example they may be unable to safely navigate roads when confronted with vehicles that emit dazzling headlamp light, and their eye health is also likely to be affected. This impacts on large numbers of people, in particular in cities and suburban areas.

The present invention is directed to overcoming at least some of the problems set out above.

The invention relates generally to a headlamp adaptor which will modify a beam of a headlamp to which it is affixed so the vehicle can be driven on the opposite side of the road, in particular selectively reducing the amount of dazzling light transmitted by the headlamp while providing sufficient illumination of the road ahead. It is accepted that light which causes ‘dazzle’ occurs in the ‘blue’ part of the visible spectrum and so such an adaptor is directed to reducing the amount of blue light in that part of the far field illumination pattern directed to the side of the vehicle adjacent the pavement, and which is directed to oncoming traffic when the vehicle is driven on the opposite side of the road. Such an adaptor may reduce the amount of blue light by filtering the blue light, blocking the blue light, or by other means.

In a first embodiment the invention relates to a headlamp adaptor, attachable to a headlamp cover of a motor vehicle, the dipped beam of which headlamp provides a far field illumination pattern, the adaptor position-able on a cover of the headlamp to intercept a portion of the headlamp beam directed to the near side of the road and modify selected wavelengths thereof.

Preferably the adaptor position is adjustable to control the portion intercepted.

Preferably the modification includes reducing the transmission of light of wavelength between 280 - 500 nm

Preferably the modification includes reducing the transmission of light of wavelength between 300 - 480 nm.

Preferably the modification includes reducing the transmission of light of wavelength between 320 - 450 nm.

Preferably the adaptor includes a central portion and wings extending away from the central portion

Preferably the central portion is circular.

Preferably adjusting the adaptor position on a headlamp cover provides for the wings to intercept that portion of the beam that provides the nearside portions of the far field illumination pattern.

Preferably the adaptor further comprises a surface, and still further comprises a filter coating on apart or parts of said surface, said filter coating adapted to modify at least a portion of selected wavelengths passing through said part or parts.

Preferably the filter coating is adapted to accommodate the orientation of the headlamp cover when modifying said selected wavelengths.

Preferably the coating is adapted to accommodate the angle between the adaptor surface and the main axis of a headlamp beam.

Preferably the coating is adapted by controlling the thickness of the coating surface. Preferably the coating is adapted by controlling a uniformity of the coating.

Preferably the coating is adapted by controlling a composition of the coating. Preferably the coating is adapted by controlling the positioning of the coating.

Preferably the portion of the headlamp beam normally directed to the near side of the road is diffused or attenuated to avoid dazzling traffic on the opposite side of the road.

Preferred embodiments of the present invention will now be described by way of example only and with reference to the accompanying drawings in which:

Figure 1 (a) shows a the view ahead for a driver relying on a conventional configuration of dipped beam headlamp light when driving in the dark,

Figure 1 (b) shows a standard modem asymmetric dipped beam pattern produced by a UK type headlamp beam,

Figure 1 (c) shows a standard modern asymmetric dipped beam pattern produced by a European type headlamp beam,

Figure 2 shows a drivers view of a dipped beam pattern produced through an adaptor in accordance with an embodiment of the present invention,

Figure 3 shows a graph of simple filter performance of an adaptor in accordance with an embodiment of the present invention,

Figure 4 (a) shows a headlamp adaptor in accordance with a first embodiment of the present invention,

Figures 4 (b) and (c) show respective sides of a headlamp adaptor in accordance with a second embodiment of the present invention,

Figure 4 (d) shows a headlamp adaptor in accordance with a third embodiment of the present invention,

Figures 4 (e) and (f) show a headlamp adaptor in accordance with a fourth embodiment of the present invention, and

Figure 5 (a), (b) and (c) show the process and method of applying a headlamp adaptor to a headlamp in accordance with a fifth embodiment of the present invention.

Headlamp light is generally directed forwards of the vehicle to light the road ahead for the driver, and is also directed slightly to the nearside to also light up at least part of the nearside portion of the road or the pavement. The light provided by a headlamp must balance the need for the driver to see the road ahead and the need for any other road user not to be dazzled by the headlamp beam. This balance is achieved by providing a dipped headlamp beam adapted to illuminate a portion of the road ahead without shining directly ahead and into the eyes of a driver in front, and also by directing the headlamp beam towards the nearside so that the driver can see the pavement, road signs and so on.

Figure 1 (a) shows the view, for a driver, of the road ahead when driving at night with the headlamp on dipped beam. Fig 1 (a) shows how the beam illuminates the road directly ahead 20 and slightly to the nearside 30, but not the road further ahead to avoid shining light into the eyes of any driver in a vehicle in front.

Figure 1 (b) shows the acceptable profile 100 of a motor vehicle dipped beam in accordance with UK vehicle regulations - specifically UK MOT requirements, with the beam directed ahead and to the left hand side of the vehicle. In particular Fig 1 (b) indicates where the maximum intensity, or hot spot, of the light occurs, for example at position 120, and also at position 130, position 130 indicating the portion of light which extends above and parallel with a horizontal upper limit of emitted light, illuminating the nearside of the vehicle when the vehicle is driven on the side of the road for which it is designed.

Figure 1 (c) shows the acceptable profile 150 of a dipped beam in accordance with European vehicle regulations, showing the asymmetric dipped beam pattern with a ‘kick-up’ portion 160 directed to, in this case, the nearside of the vehicle as defined for vehicles suitable for driving in the UK.

As discussed above, light emitted by vehicle headlamps generally covers the entire visible electromagnetic spectrum, and this light may well satisfy regulations, however certain components of the light, such as light from the high energy end of the spectrum, for example blue or ultra violet light, may have an adverse effect on other road users or pedestrians and the like. Increasingly, manufacturers are seeking to achieve greater illumination of the road ahead by fitting vehicles with headlamp units that direct light from, for example, a thermal or halogen bulb, such as for example HID, LED or laser bulbs, through a projector lens, and this has a consequence of producing a fairly pronounced chromatic split of the beam. As a result the hotspot and the part immediately above the horizon line generally take on a blue hue due to this chromatic split, as significant portions of the higher energy electromagnetic radiation is directed to this portion of the far field illumination pattern. Such high energy radiation contributes significantly to the ‘dazzle’ effect of headlamp light on other traffic and on pedestrians, and can have a particularly adverse effect on the health of those subject to it, particularly on eye health, causing the eyes to become at least tired and irritated, even though overall the light emitted is generally within allowed parameters. A major contribution to reducing the amount of dazzle suffered by other traffic or by pedestrians would therefore be to reduce the amount of high energy, or blue, light, for example light of wavelength 280 - 500 nm, 300 - 480nm, or more particularly wavelength 320 - 450nm, comprising relevant portions of the beam. For example the relevant portion of the beam is that portion directed to illuminate the side of the vehicle adjacent the pavement when the car is being driven: this would be the nearside of the vehicle when the car is driven in the country for which it is designed (specifically sections 120, 130 or 160 in Figures 1 (b) and (c) respectively), and the opposite side of the vehicle when the vehicle is being driven in countries where vehicles drive on the opposite side of the road.

Dazzle reduction can be accomplished by providing an adaptor on the headlamp cover which, in addition to modifying the headlamp beam so the vehicle may be driven legally in countries in which vehicles drive on the opposite side of the road, intercepts that part of the headlamp beam that provides the side portions of the far field illumination pattern and filters out or blocks the blue light therefrom, leaving the remainder of the light unaffected. Thus a desired lighting effect of the headlamp beam - that of alerting oncoming traffic and sundry pedestrians to the presence of the vehicle - will be retained, but the high energy part of the beam which, when present in the upper or nearside portion of the beam dazzles and irritates the eye, is filtered out or blocked.

In accordance with one embodiment, an adaptor in accordance with this invention may be made from a plastics material which has had a dye added during manufacture, so that the plastics from which the adaptor is made can modify light passing therethrough.

In accordance with a further embodiment, an adaptor in accordance with this invention includes a carefully designed filter coating applied to certain parts. The role of this filter coating is to selectively block or reduce certain wavelengths, or ranges of wavelengths, from passing through portions of the headlamp adaptor which has the coating applied thereto, thus directing only part of the spectrum of light from the bulb or LED towards the side regions of the far field illumination pattern.

It is contemplated that the coating has the effect of a long pass filter on spectral components of the beam as the beam passes through the coated adaptor. For example, at least some of the blue light from that part of the beam directed mostly towards the pavement, road signs, and pedestrians, may be removed by the filter coating, as required, to avoid blue glare, without affecting the spectral makeup of the light incident mainly on the road surface. As an example, Figure 2 shows the far field illumination pattern 200 produced by a headlamp, and further shows the beam portion 210 from which the blue, high energy, light has been filtered out or blocked compared with the rest of the beam 220 which has not been subject to such filtering or blocking.

Relying on a coating applied to particular portions of the headlamp adaptor to selectively block certain wavelengths or ranges of wavelengths presents some problems. In particular, the amount of light filtered or blocked on passing through such coated portions of the adaptor varies dependant on the angle between the plane of the coated adaptor surface and the main axis of the headlamp beam. This main axis is usually horizontal, for example parallel to the road surface, but modem headlamp covers include a wide variety of shapes and orientations in relation to the headlamp beam so that an adaptor applied to the headlamp cover may be at any one of a variety of angles to the main axis of the headlamp beam, depending on the vehicle. Variation of the angle between the adaptor surface and the main axis of the headlamp beam results in variation of the wavelength of light filtered or blocked. Consequently it is not straightforward to position an adaptor to intercept the correct portion of the beam, and further to filter or block the required wavelengths from that correct portion.

For example when the coated adaptor surface is at approximately 30 degrees to the beam the peak blocking wavelength may shift more than 50 nm, and such a shift could lead to undesired effects such as, for example, the removal of the entire blue light component, depending on the transmission properties of the filter. Other angles shift the wavelength different amounts, meaning that the peak blocking wavelength may shift different amounts also.

Figure 3 shows a filter transmission curve of an adaptor in accordance with the present invention, showing how the filter performance varies with wavelength at a standard adaptor to beam axis angle. In particular Fig 3 shows that 50% of light of wavelength in the region of approximately 340 - 480 nm is filtered, whereas almost none of the light of wavelength 570 -700 nm is filtered. Changing the angle of the adaptor to the main beam might shift this performance to achieve a completely different effect.

The design of the filter coating to be applied to the adaptor as well as the design of the adaptor itself must therefore take into account the range of angles of the headlamp cover to the main axis of the headlamp beam found in the most common vehicle headlamp models available to drivers to provide a product that is suitable for use with a wide range of orientations. A headlamp adaptor with such a filter coating design selectively applied would, when applied to a headlamp cover, filter out the high energy, ‘blue’ portion of light transmitted by the headlamp from for example that portion of the beam that is directed to the side of the road, providing an effective reduction in eye strain and irritation for other road users and pedestrians, particularly in cities where vehicles and their lights are difficult to avoid.

Figures 4 (a) - (f) provide examples of headlamp adaptors which provide the functionality discussed, when a filter coating is applied thereto.

Figure 4 (a) shows a headlamp adaptor with a central portion, in the present case disc, 402 and wings 404 extending outwardly and away from the disc 402. The central portion is provided to intercept part of a central portion of the headlamp beam of the headlamp to which the adaptor is affixed, as it exits the headlamp cover, and scatter, diffuse, attenuate or otherwise modify the headlamp beam such that the vehicle may legally be driven in countries where vehicles are driven on the opposite side of the road.

In addition, wings 404 are adapted to intercept that portion of the headlamp beam (120, 130, 160) directed to the near side of the road and filter or block the high energy, for example ‘blue’, part.

With the headlamp adaptor positioned on the cover of a headlamp such that disc 402 intercepts and modifies a part of the central portion of the headlamp beam, the adaptor may be rotated around disc 402 such that wings 404 gradually intercept portions of the beam. As the wings intercept portions of the beam, that portion of the far field illumination pattern generated by the headlamp which illuminates the near side of the vehicle when the vehicle is driven in the UK (for example area 210 in Fig 2) is intercepted to reduce or block transmission of the high energy part of the spectrum, reducing glare, and diffusing, attenuating or otherwise modifying the illumination.

The remaining far field illumination pattern generated by the headlamp is not further altered by the adaptor so that the driver retains the benefit of a well-lit road ahead, ensuring optimum lighting conditions for safe driving.

Figures 4 (b) and (c) show two sides of a second embodiment of the present invention, in which a disc 412 has a single wing 414 extending outwardly and away therefrom. Again, with the disc 412 positioned to intercept part of a central portion of the headlamp beam, the adaptor of Figures 4 (b) and (c) may be rotated until it intercepts that portion of the beam that contributes to the side portion of the far field illumination pattern.

Figure 4 (d) shows a third embodiment of the present invention, in which disc 422 has a single wing 424 extending outwardly and away therefrom, with a different wing shape to that of the adaptor of Figures 4 (b) and (c).

Figure 4 (e) shows a fourth embodiment of the present invention in which central portion 432 is shaped more like a comma than the disc of Figure 4 (d), with a tail portion 433 extending away from the disc. Similar to the adaptor shown in Figure 4 (d), the adaptor of Figure 4 (e) also has wings 434, 435 but as may be seen the tail of the comma 433 extends into one of the wings 434 reducing the portion of that wing adapted to filter out or block part of the high energy portion of light emitted by the headlamp.

Figure 4 (e) shows the dimensions of the adaptor in accordance with the fourth embodiment, and these dimensions are broadly typical of the adaptors, regardless of the embodiments relied upon. As can be seen the first dimension T is the distance between the tip of the adaptor adjacent the end of the comma distal the central disc, and a midpoint edge. The second dimension ‘j’ is the distance between a first side of the central disc at a first mid-point edge and the second midpoint edge. The third dimension is the distance ‘k’ between the two tips of the adaptor, the first tip at the end adjacent the end of the comma tail, and the second tip distal the comma. The fourth dimension is the distance between the widest portion of the second tip of the adaptor distal the comma and the point at which the mid-point edge is measured.

It is contemplated that T is between 35 and 50 mm, more particularly between 41 and 45 mm, more particularly still approximately an exemplary 43 mm. It is further contemplated that ‘j’ is between 32 mm and 42mm, more particularly between 35 and 39mm, more particularly still approximately an exemplary 37mm. It is still further contemplated that ‘k’ is between 70mm and 80mm, more particularly between 73 and 77mm, still more particularly an exemplary 75mm. Finally it is contemplated that ‘F is between 30mm and 40mm, more particularly between 34mm and 36mm, more particularly still an exemplary 35mm. From these dimensions it may be seen that the distance between the comma disc to the tail end of the comma is greater than from the comma disc to the tip at the other end of the adaptor.

Figure 4 (f) shows a fifth embodiment of the present invention. This embodiment is similar to the fourth embodiment, with a central comma shaped portion 441 with a central portion 442 and a tail 443, and wings 445, 446. Wing 446 is slightly larger than the corresponding wing 434 of Figure 4 (e), with a slightly greater area (446 & 447) not covered by comma shaped portion 441. Wing 445 is also slightly increased in size compared to the corresponding wing 435 of Figure 4 (e), specifically the inner curve 446 is more pronounced.

Figures 5 (a) - (c) show the headlamp adaptor of Figure 4(f) being applied to a headlamp cover 501 to modify that part of the headlamp light 502 illuminating the near side of the vehicle.

Figure 5(a) shows a headlamp cover 501 and the location of the beam 502 as it passes through the cover.

Figure 5(b) shows that part of the beam 504 that for example illuminates the near side of a vehicle when the vehicle is driven in the UK.

Figure 5(c) shows the adaptor of Figure 4(e) positioned on a headlamp cover 501, with a portion of the adaptor intercepting the portion 504 of the beam identified in Figure 5(b). An advantage of the present adaptor is that it is rotatable about a pivot point 510 relatively central to the central portion 512/442, with tail 443 providing for fine control over the portion of the beam intercepted by the adaptor to ensure that the correct portion of the near side illumination pattern is modified. This rotational adjustment in particular provides for fine control over the amount of overlap between the adaptor, in particular comma portion 441 and the headlamp beam and thus fine control over the amendment of the far field illumination pattern.

While the filter coating has been discussed as providing a significant component of the functionality of the headlamp adaptor in respect of filtering the headlamp light to remove or reduce the ‘blue’ component of light, thereby reducing dazzle, as stated the arrangement of the headlamp adaptor on the headlamp is also significant in providing this functionality. In particular, the shape of the headlamp adaptor (400, 410, 420, 430, 440) provides a versatility as the adaptor can be selectively oriented on a headlamp to intercept the headlamp light, in particular the ‘blue’ portion of the headlamp light. Beneficially, the effect of orientating the headlamp adaptor can be independent of the angle between the adaptor surface and the main axis of the headlamp beam.

As can be seen the headlamp adaptors 400, 410, 420, 430, 440 of Figures 4 (a) - 4 (f) comprise a respective main portion 402, 412, 422, 432, 442 with respective wings 404, 414, 424, 434, 435, 445, 446 extending outwardly and away from the main portion.

When driving a vehicle on the opposite side of the road to that for which it is designed, any one of the headlamp adaptors of Figures 4 (a) - (f)can be positioned on a headlamp cover such that the main portion 402, 412, 422, 432, 442 of the adaptor intercepts part of the central portion of a headlamp beam as it exits the headlamp cover, to modify the beam so that the vehicle may legally be driven in countries in which vehicles drive on the opposite side of the road, in particular the adaptor may be rotated on the cover until the wings 404, 414, 424, 434, 435, 445, 446 intercept that portion of the headlamp beam that provides the side portion of the far field illumination pattern. Once the adaptor position has been determined the respective wings will provide for a reduction in the high energy, for example ‘blue’, light provided to the far field illumination pattern, thereby reducing the dazzle effect of the headlamp beam.

The final, optimum position of the adaptor - i.e. the position at which the relevant ‘blue’ light is intercepted - will depend on the shape and orientation of the headlamp cover, and this will depend on the vehicle, however as stated, the adaptor shape is such that the adaptor can be rotated until the optimum position for any particular vehicle is reached. The particular shape of the adaptors of Figures 4 (a) - (f) provide for adjustment of the amount of ‘blue’ light arriving at the side of the far field illumination pattern to reduce for example dazzle to oncoming traffic when driving in countries where vehicles drive on the opposite side of the road and to reduce dazzle for, for example, pedestrians, cyclists, and so on by the simple expedient of rotating the adaptor on the headlamp cover.

It is contemplated that a set of instructions will be sufficient to indicate where the adaptor may be positioned and how that position may be adjusted for example via rotation to filter out or block selected portions of the high energy portion of the beam.

As stated, an advantage of the adaptors of Figures 4 (a) - 4 (f) is that they provide a significant tolerance of the angle between the beam and the headlamp cover surface, such that the reduction in the high energy component of headlamp light is not significantly dependent on the orientation of the headlamp cover compared to the axis of the headlamp beam, in particular the reduction in the high energy component of the headlamp light does not vary significantly with the angle of the headlamp cover, and hence the significance of the angle of the headlamp adaptor to the beam is reduced or can be disregarded completely.

This provides for a headlamp adaptor which is suitable for use for the majority of vehicles on the road, and means that a simple guide may be provided with the adaptor to indicate, for the user, where the adaptor should be positioned on the headlamp to achieve optimum functionality.

Diffusion of the headlamp light via the adaptor will ‘spread the light’ once the high energy part of the light is modified, and so will direct a portion of the light to shine on the pavement etc when the vehicle is driven in countries where they drive on the opposite side of the road.

The headlamp adaptor of the present invention may be used to reduce dazzle for oncoming traffic when the vehicle is driven on the opposite side of the road, for example when driving abroad.

In accordance with a further embodiment, the present invention is directed to a method of fitting a headlamp adaptor on a headlamp cover to modify the headlamp beam so the vehicle is suitable for legally driving the vehicle in a country where they drive on the opposite side of the road.

The method includes switching the headlamps to dipped beam, placing the adaptor on the headlamp cover with the central portion 402, 412, 422, 432, 442 extending slightly over the central portion as shown in Figure 5(c), and holding a piece of paper distal the headlamp cover upon which the light generated by the headlamp may be seen.

The user will see that the portion of the dipped beam directed to the nearside of the road when the vehicle is legally driven in the country for which it is designed has been modified. The light is less intense as the ‘blue’ high energy portion of the light has been modified. The adaptor may be rotated about pivot point 510 so that wings 506, 514, 516 move to intercept different portions of the beam and have a consequent effect on the far field illumination pattern, in particular the portion of the far field illumination pattern that will shine on the near side of the vehicle.

Once a user is satisfied that the correct portion of the beam has been intercepted and modified, the adaptor may be affixed to the headlamp cover.

The piece of paper referred to above may include guidelines to that as the adaptor rotates, different parts of the paper are illuminated, the paper including an indication of the desired spread of light, i.e. which will reflect the desired outcome for applying the adaptor to the cover.

Thus the adaptor of the present invention provides for a headlamp adaptor which is adapted to modify a headlamp beam to illuminate an appropriate side of the of the road while intercepting a suitable portion of the beam to filter out high energy ‘blue’ light which may dazzle other road users.

The present invention is directed to a headlamp adaptor which is suitable to be applied to a vehicle headlamp of a vehicle suitable for driving in a country where vehicles are driven on one side of the road, to adapt the headlamp beam so that it is suitable for the vehicle when driven in countries in which vehicles are driven on the opposite side of the road. The invention is further directed to a headlamp adaptor which is suitable to limit the capacity of the headlamp to dazzle, thereby preventing other road users, pedestrians etc from being dazzled. Reducing such dazzle enhances the safety of the roads as the driving of dazzled drivers is compromised, sometimes severely, and pedestrians and other road users are better able to tailor their behaviour to the circumstances if they are not dazzled.

In use, the headlamp beam should be switched on and a piece of paper held in front so that the headlamp beam illuminates the sheet. An adaptor in accordance with the present invention may then be placed on the headlamp cover so that a portion (402, 412, 422, 432, 442) impinges upon the beam, in particular upon a side of the beam. The side of the beam selected determines which side of the far field illumination pattern is modified by the adaptor, and the side of the far field illumination pattern affected will be the opposite side to the part of the beam covered.

Once the adaptor is roughly positioned on the headlamp cover the adaptor may be rotated around a central portion of the adaptor, for example point 510 of Figure 5 (c) while observing the pattern on the sheet. The pattern on the sheet will change as the adaptor is rotated, and once a desired pattern is achieved the adaptor may be attached to the headlamp cover, with the user secure in the knowledge that the headlamp light will be modified by the adaptor to remove the ‘blue’, high energy portion of headlamp light, avoiding dazzling oncoming traffic when driving on the opposite side of the road, and that the headlamp light will be scattered, diffused or attenuated to shine more directly towards the pavement when the vehicle is driven in countries where vehicles are driven on the opposite side of the road.

The invention is not restricted to the details of the foregoing embodiments. For example the central disc 402, 412, 422, 432, 442 may have a different suitable shape, i.e. may not be a disc. Regions of the adaptor are provided to selectively filter out or block the high energy portion of the beam, however the regions may modify the beam in other ways. The wavelength of light identified as being impacted is stated to be in the range 280 - 500 nm, or 300 - 480 nm, or more particularly 320 - 450 nm. Specifically the wavelength of light impacted is light in the ‘blue’, high energy part of the visible spectrum.

Claims

1. A headlamp adaptor for attachment to the headlamp of a motor vehicle, the dipped beam of which headlamp provides a far field illumination pattern, the adaptor position-able on a cover of the headlamp to intercept a portion of the headlamp beam directed to the near side of the road and modify selected wavelengths thereof.

2. A headlamp adaptor in accordance with claim 1, wherein the position is adjustable to control the portion intercepted.

3. A headlamp adaptor in accordance with claim 1, wherein the modification includes reducing the transmission of light of wavelength between 280 - 500 nm.

4. A headlamp adaptor in accordance with claim 3, wherein the modification includes reducing the transmission of light of wavelength between 300 - 480 nm.

5. A headlamp adaptor in accordance with claim 4, wherein the modification includes reducing the transmission of light of wavelength between 320 - 450 nm.

6. A headlamp adaptor in accordance with claim 1, wherein the adaptor includes a central portion and wings extending away from the central portion

7. A headlamp adaptor in accordance with claim 6, wherein said central portion is circular.

8. A headlamp adaptor in accordance with claim 6, wherein said position on a headlamp cover is adjustable to provide for said wings to intercept that portion of the beam that provides nearside portions of the far field illumination pattern.

9. A headlamp adaptor as claimed in claim 1 or claim 6, further comprising a surface, and further comprising a filter coating on a part or parts of said surface, said filter coating adapted to modify at least a portion of selected wavelengths passing through said part or parts.

10. A headlamp adaptor in accordance with claims 9, wherein said filter coating is adapted to accommodate the orientation of the headlamp cover when modifying said selected wavelengths.

11. A headlamp adaptor in accordance with claim 10, wherein said coating is adapted to accommodate the angle between the adaptor surface and the main axis of a headlamp beam.

12. A headlamp adaptor in accordance with claim 10 or claim 11, wherein the coating is adapted by controlling the thickness of the coating surface.

13. A headlamp adaptor in accordance with claim 10 or claim 11, wherein the coating is adapted by controlling a uniformity of the coating.

14. A headlamp adaptor in accordance with claim 10 or claim 11, wherein the coating is adapted by controlling a composition of the coating.

15. A headlamp adaptor in accordance with claim 10 or claim 11, wherein the coating is adapted by controlling the positioning of the coating.

16. A headlamp adaptor in accordance with any of the preceding claims wherein the portion of the headlamp beam normally directed to the near side of the road is diffused or attenuated to avoid dazzling traffic on the opposite side of the road.

17. A headlamp adaptor as herein described with reference to the accompanying description.

18. A headlamp adaptor as herein described with reference to the accompanying drawings.