A beacon light can be used to mark an obstacle that may provide a hazard to vehicles, aircrafts and boats. Previous beacon lights generally exhibit relatively poor energy efficiency, which can prohibit the use of solar panels to power the beacon light. Previous beacon lights may also contribute to light pollution, i.e., direct light at angles undesirably above and below a specified plane.
Some beacons, such as those used for marine navigation, require that the light only be seen when viewed from a specific angle or angular range. The light must be blocked from other specific angles or angular range. This allows ships to navigate safely by allowing them to identify the beginning or end of a hazard. Blocking the light output from certain angles eliminates confusion when multiple lights are located in a common area. This also allows ships to navigate safely by allowing them to identify the beginning or end of a hazard.
Some beacons use multiple light sources arranged along a horizontal plane. However, blocking the light output when using multiple light sources arranged along a horizontal plane does not provide for a sharp cutoff of the light in the horizontal axis. This is because the shield gradually blocks the light from each light source as the ship passes. As a result, the light will appear to slowly fade out as a ship passes by the beacon light.
The present disclosure relates generally to an omnidirectional light optic having a horizontal cutoff. In one embodiment, the omnidirectional light optic comprises a plurality of reflectors, wherein each one of the plurality of reflectors comprises at least two reflective sides, wherein each one of the at least two reflective sides has an associated optical axis, wherein each respective optical axis of the at least two reflective sides is located on a common horizontal plane and each one of the at least two reflective sides comprises a curved concave cross-section, a plurality of light emitting diodes (LEDs), wherein each one of the plurality of reflectors is associated with at least one of the plurality of LEDs, wherein each one of the plurality of LEDs and each one of the plurality of reflectors is vertically stacked with respect to one another and at least one blocking band member with at least one edge that blocks light emitted by the plurality of LEDs at common horizontal angles.
The present invention also provides a second embodiment of an omnidirectional light having a horizontal cutoff. In the second embodiment, the omnidirectional light comprises a plurality of light optics, wherein each one of the plurality of light optics is vertically stacked and at least one blocking band member with at least one edge that blocks light emitted by the at least one LED at common horizontal angles. Each one of the plurality of light optics comprises at least one reflector, wherein the at least one reflector comprises at least two reflective sides that converge at an apex, wherein each one of the at least two reflective sides has an associated optical axis, wherein each respective optical axis of the at least two reflective sides is located on a common horizontal plane, wherein each one of the at least two reflective sides comprises a curved concave cross-section and at least one light emitting diode (LED), wherein the at least one LED is positioned below the apex of the at least one reflector.
The present invention also provides a second embodiment for an omnidirectional light having a sharp horizontal cutoff. In one embodiment, the omnidirectional light comprises a first light optic, a second light optic, a third light optic and at least one blocking band member with at least one edge that blocks light emitted by the first LED, the second LED and the third LED at common horizontal angles. The first light optic comprises a bottom plate, a first top plate, a first reflector coupled to the first top plate, wherein the first reflector comprises at least two reflective sides that converge at an apex, wherein each one of the at least two reflective sides comprises a curved cross-section, a first light emitting diode (LED) coupled to the bottom plate, wherein a central light emitting axis of the first LED is positioned at the apex of the first reflector and one or more first standoffs coupled to the first top plate and the first bottom plate. The second reflector comprises a second top plate, a second reflector coupled to the second top plate, wherein the second reflector comprises at least two reflective sides that converge at an apex, wherein each one of the at least two reflective sides comprises a curved cross-section, a second LED coupled to the first top plate, wherein a central light emitting axis of the second LED is positioned at the apex of the second reflector and one or more second standoffs coupled to the first top plate and the second top plate. The third light optic comprises a third top plate, a third reflector coupled to the third top plate, wherein the third reflector comprises at least two reflective sides that converge at an apex, wherein each one of the at least two reflective sides comprises a curved cross-section, a third LED coupled to the second top plate, wherein a central light emitting axis of the third LED is positioned at the apex of the third reflector and one or more third standoffs coupled to the second top plate and the third top plate.
So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures.
Embodiments of the present disclosure are directed towards an omnidirectional light having a sharp horizontal cutoff. The sharp cutoff is achieved using a blocking band member to block a set portion of light emitted by the omnidirectional light. As noted above, previous omnidirectional light sources use a horizontal arrangement of light sources along a plane. However, blocking the light output when using multiple light sources arranged along a horizontal plane does not provide for a sharp cutoff of the light in the horizontal axis. This is because the shield gradually blocks the light from each light source as the ship passes.
This can be seen in
As the ship begins to pass the omnidirectional light, the light blocking band member creates an obstruction to the first LED and the light reflected by the reflector and, therefore, the light emitted by the first LED cannot be seen. The intensity level seen by the observer would be at about 67% and illustrated moving to the left of the graph and the first step down in
As the ship pass further by the omnidirectional light then the light blocking band member creates an obstruction to the second LED and the light reflected by the reflector and, therefore, the light emitted by the second LED cannot be seen. The intensity level seen by the observer would be at about 33% and illustrated moving to the left of the graph and the second step down in
As the ship pass even further by the omnidirectional light then the light blocking band member creates an obstruction to the third LED and the light reflected by the reflector and, therefore, the light emitted by the third LED cannot be seen. The intensity level seen by the observer would be at about 0% and illustrated moving to the left of the graph and the third step down in
The light cutoff for the horizontally aligned LED design shown in
One embodiment of the present disclosure overcomes the deficiency of the horizontal arrangement of light sources by providing a vertically stacked arrangement of light sources. The vertically stacked arrangement provides an omnidirectional light source that has a sharp horizontal cutoff using a blocking band member.
Using the blocking band member 150 illustrated in
In one embodiment, the blocking band member 150 may block light emitted from each one of the LEDs 104 at approximately the same horizontal angle. In one embodiment, the blocking band member 150 may block light emitted from each one of the LEDs 104 within +/−10 degrees of one another. For example, the blocking band member 150 may use a single continuous vertical edge 156 to block the light emitted from the each one of the LEDs 104. In one embodiment, the blocking band member 150 has at least one edge that blocks light emitted by the plurality of LEDs 104 at common horizontal angles. In one embodiment, the common horizontal angles may be within +/−10 degrees of each other.
In one embodiment, the blocking band member 150 may be made from a plastic or a metal. The blocking band member 150 may be fabricated as a single unitary piece or multiple pieces. In one embodiment, the blocking band member 150 may be coupled to the omnidirectional light source 100 directly on one of the plates (e.g., the plate 166), hung on a high hat coupled to the omnidirectional light source 100 or part of a different structure that is separate from the omnidirectional light source 100. In one embodiment, the blocking band member 150 may block approximately 180 degrees around (e.g., a semicircle shape) the omnidirectional light 100. In another embodiment, the blocking band member 150 may block approximately 90 degrees around the omnidirectional light 100. The blocking band member 150 may be positioned anywhere around the omnidirectional light source 100 depending on a desired light output direction of the omnidirectional light source 100 and where the light cutoff in the horizontal direction should occur.
Referring back to
Each one of the plurality of light optics may have at least one LED 104 coupled to the bottom plate 162. The number of LEDs 104 in each one of the plurality of light optics may depend on a particular application. For example, for a 5 nautical mile application, each one of the plurality of light optics may only require a single LED 104 and three vertical levels of light optics. For 10 nautical mile applications, each one of the plurality of light optics may require three or more LEDs 104 or a single LED 104 on six vertical levels of light optics, for example, and so forth. As noted, a single LED 104 would provide a sharper cutoff than multiple LEDs on a single level.
A reflector 106 may be coupled to the top plate 160. In addition, at least one standoff 112 may be coupled to the top plate 160 and the bottom plate 162.
A similar arrangement may be found for the light optic between the top plate 162 and the bottom plate 164 and for the light optic between the top plate 164 and the bottom plate 166. Although three light optics are illustrated by example in
In one embodiment, the reflector 106 may include at least one reflective side 108. In the embodiment, illustrated in
In one embodiment, each one of the at least one reflective sides 108 may have an associated optical axis 36. The optical axis 36 may be defined as an axis along which the main concentration of light is directed after reflecting off of the reflective side 108. The at least one reflective side 108 may be designed to collimate light along the optical axis 36 to about +/−10 degrees with respect to the optical axis 36.
In one embodiment, the at least one reflective side 108 may be designed to collimate light along the optical axis 36 non-symmetrically. For example, the at least one reflective side 108 may be designed to collimate light in the vertical direction but not significantly in the horizontal direction.
In one embodiment, an optical axis 36 of a first reflective side 108 may be located at about 180 degrees apart with respect to an optical axis 36 of a second reflective side 108. In one embodiment, an optical axis 36 of a first reflective side 108 may be located at about 180 degrees apart with respect to an optical axis 36 of a second reflective side 108 of a common reflector 106. The reflector 106 may also include at least one non-reflective side 110. In the embodiment, illustrated in
The surface of the reflective side 108 may be curved. For example, the cross-section 40 may be curved in a conic or a substantially conic shape. In one embodiment, the conic shape may comprise at least one of: a hyperbola, a parabola, an ellipse, a circle, or a modified conic shape.
The LED 104 may also be located below an apex 102 of the reflective sides 108. In one embodiment, the LED 104 may be located such that the central light emitting axis 56 is at a center point of an apex 102 of the reflective sides 108. For example,
In one embodiment, the apex 102 of the reflector 106 may be formed by two separate reflectors 106, as illustrated in
Referring back to
In an alternative embodiment, if the omnidirectional light 100 has a reflector 106 with more than two reflective sides 108, the standoffs 112 may be fabricated from a transparent material to minimize the amount of light that is blocked. In one embodiment, a cylinder that is transparent may be used to support the plates. In one embodiment a cylinder with cutouts may be used in the omnidirectional light 100. The cutouts may allow for higher light intensity, or adjustment of the light intensity, at specific angles. In one embodiment, a filter material may be used to reduce the light intensity at specific angles. The filter material may be positioned in the optical path between the LED 104 and reflector 106 or may be placed in the optical path after the reflector 106. The filter material may be a coating on the surface of the one or more of the reflective sides 108.
In one embodiment, each one of the plurality of light optics may be arranged vertically along a common vertical axis 170. Said another way, each LED 104 and an approximate center point of each one of the reflectors 106 all lay approximately along the vertical axis 170. In one embodiment, the center of each plate 160, 162, 164 and 166, the central light emitting axis 56 of each LED 104 and a center point of each one of the reflectors 106 all lay along the vertical axis 170.
In addition, each one of the plurality of light optics may be arranged such that each optical axis 36 of each reflective side 108 is positioned at a predetermined angle.
In addition, the design of the omnidirectional light 100 of the present disclosure provides a sharp horizontal cutoff of θA as shown in
As a result, the omnidirectional light 100 provides a more efficient beacon light than previous designs, while having a sharp horizontal cutoff. For example, the omnidirectional light 100 may use a single LED 104 for each one of the plurality of light optics, which may save energy over previous designs that use an array of light sources. In addition, each one of the plurality of light optics may only need a single optical feature, for example, a single reflector unlike previous designs that require multiple optical features such as reflectors, lens, mechanical blocks, and the like.
Moreover, the omnidirectional light 100 provides a compact design. For example, adding too many vertical levels of light optics may cause the omnidirectional light 100 to be unstable and prone to toppling if run into or hit by water, debris or a water craft.
Although the omnidirectional light 100 was described above using a reflector 106 having two reflective side 108 and having three levels, it should be noted that the reflector 106 may have any number of reflective sides. As a result, the number of levels may increase or decrease. For example,
In one embodiment,
While various embodiments have been described above, it should be understood that they have been presented by way of example only, and not limitation. Thus, the breadth and scope of a preferred embodiment should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.
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