JP7042962B2 - Asymmetric light intensity distribution from luminaires - Google Patents

Description

This application is filed in US Provisional Patent Application Nos. 62 / 298,355 filed on February 22, 2016, US Provisional Patent Application Nos. 62 / 328,402 filed on April 27, 2016, and 2016. Claims priority over European Patent Application No. 16173295.3 filed on June 7, 2014. US Provisional Patent Application No. 62 / 298,355, US Provisional Patent Application No. 62 / 328,402, and European Patent Application No. 16173295.3 are incorporated herein by reference.

The present invention relates to general lighting using light emitting diode (LED) lamps, and in particular to luminaires that produce an asymmetric light intensity distribution suitable for illuminating streets, passages, walls, or other areas.

Traditional street lights are being replaced by more efficient and more reliable LED luminaires. The desired light intensity distribution is one that provides the highest peak light intensity along the street and provides very little light intensity in the opposite direction of the street. The side of the luminaire that turns its back to the street is referred to here as the "residential side", and the side of the luminaire that faces the street is referred to here as the "street side". The light intensity towards the residential side is sufficient to illuminate the sidewalk or curb along the street.

Modern street lights that use LEDs use an asymmetric lens that covers the high power LEDs to control the light intensity distribution. Alternatively, conventional secondary optical systems are used to direct the light downwards and sideways while preventing the light from being emitted toward the house. Such street lights have high glare when the observer looks directly at the luminaire. For example, one type of street light uses two rows of eight high power white light LEDs in parallel, with a separate lens on each LED. If you look directly, you can see 16 very bright point light sources. This is called pixelated lighting and is aesthetically undesirable.

What is needed is the efficiency of using LEDs, where the luminaire has a non-pixelated pattern when viewed directly and has a controllable asymmetric light intensity distribution, for example optimized for overhead street lighting. Lighting equipment.

In one embodiment, an overhead street light (lighting) with an asymmetric light intensity distribution, where the peak intensity is highest along the street direction, lower in the direction across the street, and much lower on the residential side of the street. Instrument) is formed. The intensity distribution can be a mirror image perpendicular to the street.

The luminaire has a circular transparent light guide, for example, about 15 inches (38 cm) in diameter and about 0.5 cm in thickness. A circular metal frame supports the light guide. Around the edge of the light guide, there are multiple white light LEDs on a flexible strip that inject light into the polished edge of the light guide to maintain directivity.

Multiple LEDs on the strip are divided into multiple segments (depending on the size of the luminaire), for example 12 segments. These segments may be designed or controlled to emit different amounts of light to assist in creating the desired asymmetric light intensity distribution. The amount of light emitted by each segment can be controlled by varying the number of LEDs in each segment, or by varying the current to each segment. In another embodiment, the emission from each segment is equal. Each segment may include a plurality of LEDs connected in series, or these segments may be connected in parallel.

In another embodiment, these multiple LEDs are arranged at different pitches or densities and possibly, in order to achieve the desired azimuth direction (ie, in a horizontal angular plane) light intensity distribution. Arranged in one or more LED rows depending on the degree of concentration required.

The light injected into the light guide is internally reflected until the light is taken out, so that the light is somewhat mixed in the light guide, still having some directivity.

Further, in order to control the asymmetry of the light intensity distribution, parallel serrated grooves are formed on the surface of the light guide opposite to the light emitting surface. The ditch is parallel to the street.

In one embodiment, all grooves are equal and their angles and spacings may be designed to fine-tune the light distribution and luminance uniformity across the light emitting surface. The inclined surface of the groove generally faces the residential side LED, and the vertical surface of the groove generally faces the street side LED, so that the light rays coming from either the residential side LED or the street side LED generally face the reflection on the groove surface. Directed towards the street. The spacing between the grooves can be varied along the light guide so that the light is spread more evenly over the light emitting surface of the light guide.

In another embodiment, the angle and depth of the serrated grooves are towards the street side to reduce the amount of light reflected back towards the residential side and further improve the luminance uniformity across the light emitting surface. Gradually increase.

A plurality of translucent dots, such as epoxy-based dots, may be printed on the light emitting side of the light guide, which can help increase light extraction efficiency and spread the street beam. These dots can be about 1 mm in diameter and can have Gaussian synchrotron radiation (unlike Lambersian). The Gaussian dots diffuse the incoming rays somewhat along the direction of the incident rays, for example giving a half-width half-width spread of 12 degrees. These dots can be uniformly arrayed on the surface of the light guide and can occupy about half the area of the light emitting surface. Alternatively, these dots may have a variable size distribution or a variable density distribution to improve luminance uniformity across the light emitting surface.

Instead of dots, Gaussian continuous diffusion layers or surface textures (eg, some "frosted glass" finish) may also be used.

These diffusing elements may also be arranged alternately with grooves on the back surface of the light guide. The light from the diffusing element will be further mixed in the light guide to increase uniformity.

A reflector is positioned above the optical guide so as to reflect the upward light leaking from the optical guide.

Additional inserted below the exit surface of the optical guide to provide some additional light distribution control, such as protecting the optical guide and filtering out high-angle rays to reduce glare. A transparent optical plate can be used. Further textures can be added to the light guide surface to reduce or suppress the light directed towards the residential side.

With proper selection of grooves, the relative amount of street-side lighting and residential-side lighting can be controlled. By controlling the amount of light emitted by each LED segment, the asymmetric light intensity distribution can be further controlled. By using Gaussian dots (or any other suitable diffuser), the light leaving the light guide is well diffused while remaining directional, and therefore the observer looking directly at the light emitting surface of the light guide. Will see a generally uniform and pleasing light.

In other embodiments, the light guide may be a rectangle, a rectangle with rounded corners, a parallelepiped (which may have rounded corners), or an ellipse. These optical guides may also be formed as wedges that eliminate the need for serrated grooves. Gaussian dots or other diffusers may be used.

In another rectangular luminaire, the luminaire is angled to the street and the LED strips are placed only along the two residential edges so that most of the light is directed along the street. Will be done. A prism formed in the back of the light guide further controls the asymmetry of the light intensity distribution. Gaussian dots or other diffusers may be used.

The LED may be positioned inside a hole formed near the perimeter of the light guide rather than edge-injecting the LED light into the side surface of the light guide.

The luminaire may be used for other purposes where an asymmetric light intensity distribution is desired.

Other embodiments are also disclosed.

It is a perspective view of one Embodiment (lighting fixture) of this invention used as an overhead street light. The light intensity distribution from the lamp test in FIG. 1 within a horizontal cone that intersects the vertical right angle with the highest emitted luminosity (candela), with the highest intensity along the street and the direction across the street. It shows the low light intensity of and the lowest light intensity directed to the residential side (opposite the street side). Light intensity distribution from the lamp test in FIG. 1 in a vertical plane intersecting the horizontal angle with maximum emitted luminosity (candela), most oriented along the street at a slightly downward angle. It shows a high light intensity and a much lower light intensity directed toward the residential side. Top view of a luminaire with the top cover removed, showing that the LED segment surrounds a light guide with a reflector sheet overlying it. It is a bottom view of the light guide which shows the Gaussian dot (diameter about 1 mm) printed on the light emitting surface. In one embodiment, these dots occupy about half of the bottom surface of the optical guide. It is a front view of one segment of series connected LEDs on a flexible printed circuit strip or a rigid printed circuit board, and this segment contains 5 LEDs. It is a front view of another segment of LEDs connected in series on a flexible printed circuit strip or rigid printed circuit board, which segment contains only two LEDs for reduced light output. Illustrates an array of parallel serrated grooves formed on the back of an optical guide opposite the surface containing the dots. FIG. 7 is a cross-sectional view of a part of the luminaire of FIG. 7, in which an LED that emits light to the edge of a light guide, a Gaussian dot (directional but diffusible) on a light emitting surface, and a reflector on the light guide are shown. Shows. FIG. 8 shows a luminaire in which a plurality of grooves are equal and their spacing is varied. FIG. 8 shows a luminaire in which a plurality of grooves are equal and diffuse dots are printed between the grooves. It is a cross-sectional view of a part of a rectangular luminaire, and instead of the groove of FIG. 8-10, a wedge shape may be used, and Gaussian dots are also used. FIG. 11 is a top view of the luminaire of FIG. 11 showing how the LEDs need only be arranged along the opposite edge of the wedge-shaped light guide. Top view of a flat rectangular luminaire with light guides positioned at an angle to the street, with different depths to control the asymmetric light intensity distribution (lower intensity towards the residential side). An array of prisms is formed (eg, molded) on the back, and LED strips are positioned only on the residential side of the light guide so that light is incident primarily in the direction of the street. It shows a single prism molded on the back of the light guide of FIG. 13 and shows how the rays from the two LED segments are internally reflected away from the residential side towards the street. There is. Reflectors of other shapes may be used. Multiple LED segments in a circular luminaire, such as those shown in FIG. 1, have different light powers by controlling the current to the segments in order to achieve the desired asymmetric light intensity distribution. Indicates whether it can be output. It is a bottom view of a circular light guide having a plurality of holes for receiving a plurality of ring-shaped LEDs near the outer circumference, for example, 168 holes for a 15-inch luminaire. FIG. 16 is a cross-sectional view of the optical guide of FIG. 16 further showing the LED in the hole and the reflector ring on the LED. The optical guide includes the aforementioned Gaussian dots and grooves or prisms.

Elements that are the same or similar have the same reference numeral.

The present invention shows an example optimized for use as a street light, although it can be used in a wide variety of applications. FIG. 1 illustrates a luminaire 10 supported by a support structure 12 on a street 14. The asymmetric light intensity distribution of the luminaire 10 will be described with respect to the street side and the residential side. The desired light intensity distributions are high light intensity along a particular length of the street, low light intensity extending across the street, and much lower light intensity radiated towards the residential side in the opposite direction. The light along the length of the street blends with the light from the adjacent street lights to provide fairly uniform lighting throughout the street.

The examples described below do not present a high-intensity pixelated light pattern when viewed directly by the observer. Rather, the light is spread over the entire bottom surface of the light emitting portion of the luminaire, producing a substantially uniform diffused light that is far more pleasing than a pixelated light pattern.

FIG. 2 is an example of the desired light intensity distribution 16 (measured with a candela) obtained from the lamp test of FIG. 1 within a horizontal cone intersecting the vertical right angle with the highest emitted luminosity (candela). The lighting fixture 10 is located at the intersection of the axes. Many other similar distributions are achievable, and the optimal distribution may depend on the specific characteristics of the street to be illuminated. For example, in a narrower street, the street-side strength distribution directed perpendicular to the street may be concave. In the illustrated example, the peak light intensity directed along the street (generally parallel) is about 2-3 times higher than the peak light intensity directed at right angles to the street, and the peak light intensity directed towards the residential side is , Less than one-third of the light intensity directed at right angles to the street. Such residential light can be used to illuminate sidewalks along the street, or to illuminate the curb area if the luminaire is hung well in the street.

FIG. 3 is an example of a desirable light intensity distribution 18 (measured by a candela) obtained from the lamp test of FIG. 1 in a vertical plane intersecting a horizontal angle with maximum emitted luminosity (candela). The lighting fixture 10 is located at the intersection of the axes. In the illustrated example, the highest peak light intensity is directed along the street at a slightly downward angle, while the much lower peak light intensity is directed towards the residential side. The peak light intensity on the street side is well above three times the peak intensity directed toward the residential side.

The light intensity is substantially a mirror image of the centerline perpendicular to the street.

Many other asymmetric light intensity distributions can be achieved using the structures described below.

FIG. 4 is a top view of a part of the luminaire 10 of FIG. 1 with the top cover removed. A circular metal frame 20 with a bottom opening mounts a flexible circuit tape containing a linear array of white light LEDs around its inner circumference. The white light LED may be a high power GaN-based blue light emitting LED equipped with a YAG phosphor (which produces yellow light) to produce white light. Other phosphors may be added to obtain the desired color temperature or color rendering index (CRI).

In one embodiment, the frame 20 is about 15 inches in diameter and has about 168 LEDs. These LEDs are divided into a plurality of segments 22 such as 12 segments, the LEDs in a single segment 22 are connected in series, and the segments 22 are connected in parallel. If the LED has a forward voltage of 3.5 volts, the operating voltage of the luminaire 10 is about 42 volts.

The circular light guide 24 of FIG. 5 sits in the frame 20 with the printed dots 26 facing down the street. The optical guide 24 may be a transparent polymer such as PMMA having a thickness of about 4-5 mm, for example. The print dot 26 will be described more fully in relation to FIG.

A reflector sheet 28 (FIG. 4) is positioned above the light guide 24 and the LED to reflect all light downward (the reflector sheet 28 is shown smaller so as not to obscure the LED). In one embodiment, the reflector sheet 28 is a mirror-reflecting or slightly diffused mirror sheet that substantially retains the directivity of the light beam in order to better control the asymmetry of the light intensity distribution. In another embodiment, the reflector sheet 28 may have a white surface to greatly enhance the diffusion of light. The reflector sheet 28 may be separated from the optical guide 24 or may be directly on the surface of the optical guide.

A metal cover (not shown) is mounted on the luminaire 10.

In one embodiment, the plurality of LED segments 22 are designed to emit different amounts of light in order to provide further control of the asymmetry of the light intensity distribution. FIG. 6A exemplifies an LED segment 30 designed to emit high brightness in order to be arranged along the rear (residential side) of the luminaire 10 such as the position shown in FIG. High brightness is directed away from the residential side and along the street. Five LEDs 32 are shown connected in series by a conductor 34 on the flexible circuit 36. In one actual embodiment, there may be approximately 14 LEDs within segment 22. The LED 32 generally has Lambersian radiation.

FIG. 6B illustrates another LED segment 38, which may also be used within the luminaire 10, which outputs reduced brightness. In this example, only two LEDs 32 are in segment 38. The segment 38 may be placed in the position shown in FIG. 4 to provide low brightness towards the residential side.

The LED segments 22 at other positions around the light guide 24 may be designed to have different light outputs to further customize the light intensity distribution. Alternatively, different currents may be applied to the same LED segments 22 to customize the light output from the segments 22.

In one embodiment, each segment 22 around the light guide is equal and receives the same current, and the light intensity distribution of the lamp is customized using other techniques, for example, as described below. ..

FIG. 7 illustrates the optical guide 24 of FIG. 5 and shows a parallel groove 40 formed or machined on the surface of the optical guide 24 opposite to the surface having the dots 26. The groove 40 is serrated. The width of each groove 40 may be between 0.5 mm and 4 mm. The groove 40 directs the light that hits it downward toward the street side, and reduces the amount of light that is reflected internally from the edge of the light guide 24.

FIG. 8 is a cross-sectional view of a lighting fixture 10 showing an embodiment of the groove 40 and the print dot 26. The LED 32 mounted on the flexible circuit 36 is shown to emit white light into the light guide 24. Light is generally reflected by TIR on the smooth inner surface of the optical guide 24 until it is reflected downward by the angled groove 40 or hits the translucent dot 26. The dots 26 can be epoxy-based and are diffuse particles that only slightly diffuse the light, for example by spreading the light at 12 degrees HWHM around the direction of the light beam 42 that hits it. (For example, TiO ₂ , high refractive index microbeads, etc.) may be included. This retains some directivity of the light it hits, but diffuses the light well enough to make the luminaire look uniform white to the observer. A portion of the diffused light from the dot 26 is also reflected back into the light guide 24 and finally escapes.

The groove 40 has a length parallel to the street, and the inclined surface of the groove 40 is angled downward so as to receive most of the incident light from the residential side LED (left side). In addition, in order to gradually increase the chance that the light beam coming from the residential side of the luminaire will be reflected downward by the groove 40, how the groove 40 is placed in the light guide 24 at an increasing angle. Please note that it will get deeper and deeper. This greatly reduces the amount of light that will be reflected back to the home side at the right edge of the light guide 24 and reduces the amount of light emitted towards the home side. Further, changing the depth / angle of the groove 40 directs the light from the residential side LED more uniformly toward the light emitting surface of the light guide 24. This is because the amount of light from the residential side LED in the light guide 24 is gradually emitted along the length of the light guide 24 while being increasingly obstructed by the changing depth / angle groove 40. This is because it is gradually reduced. Therefore, there is good light uniformity on the light emitting surface of the light guide 24 while still maintaining the asymmetric light intensity distribution shown in FIGS. 2 and 3.

Conversely, the generally vertical surface of the angled groove 40 reflects most of the street-side LED light back to the street-side, increasing emission from the street-side. Since the street-side LED is arranged around 180 degrees in front of the light guide 24, the light from the street-side LED is reflected away from the residential side and radiated toward the street. In another embodiment, the grooves 40 all have the same angle and become deeper and deeper, and the width of the grooves 40 gradually increases towards the street side.

The light leaking from the top surface of the optical guide 24 is reflected back into the optical guide 24 by the reflector sheet 28. As mentioned earlier, the reflector sheet 28 can be specular (for the highest directivity), diffuse specular (for the lowest directivity), or white (for the lowest directivity).

In one embodiment, the dots 26 cover about half of the bottom surface of the optical guide 24, so that about 50% of the light that enters the optical guide 24 goes out without being diffused by the dots 26, and the remaining 50%. Is diffused by the dots 26. The dots 26 are non-hemispherical, such as rounded rectangles, rounded triangles, flat top circles, flat side prisms, or other suitable shapes that produce diffuse Gaussian radiation. You may.

By controlling the depth of the grooves 40 and their angles, the light intensity distributions of FIGS. 2 and 3 can be obtained. Further control of the distribution can be obtained by controlling the relative light output powers of the various LED segments 22 (FIG. 4).

FIG. 9 shows the luminaire of FIG. 8 in which the plurality of grooves 43 in the light guide 44 are equal and their spacing is varied. The grooves 43 get closer to each other as the grooves 43 approach the street side and reflect more light downward. Since the light from the residential LED is gradually reduced along the light guide 44, the increased density of the groove 43 is more uniform when looking directly at the light along the light emitting surface of the light guide 44. Let me.

In another embodiment, the asymmetric light intensity distributions of FIGS. 2 and 3 are still achieved while the grooves 43 are evenly spaced. This is because the light from the residential side LED is generally directed downward by the inclined surface of the groove 43, whereas the light from the street side LED is generally returned by the vertical surface of the groove 43 facing the street side LED. Because it is reflected (and eventually downwards).

FIG. 10 shows a luminaire of FIG. 8 in which a plurality of grooves 45 in the optical guide 46 are equal and diffuse Gaussian dots 26 are printed between the grooves 45. The dot 26 redirects the incident light beam up and down in a diffusive / directional manner. The light directed upward is reflected downward by the reflector sheet 28 and returned. Even if the light emitting surface of the light guide 46 has a diffusion layer 47, for example, whether it is a laminated sheet or formed by machining or molding the light guide 46. good. The amount of diffusion should be limited to achieve the asymmetric light intensity distribution of FIGS. 2 and 3.

Other diffusion elements may be formed on the grooved surface, for example by roughening the surface or forming a prism on the surface.

Circular luminaires have some advantages over rectangular luminaires, but good asymmetric light intensity distributions can still be achieved with rectangular luminaires. FIG. 11 is a cross-sectional view of a rectangular optical guide 50 having an angled top surface (wedge shape) covered with a reflector sheet 52. FIG. 12 is a top view of the lighting fixture of FIG. The angled surface allows most of the light emitted by the residential side LED (left side) to exit the light guide 50 away from the residential side. The light may exit the light guide 50 directly or be slightly diffused by the dots 26. Much of the light emitted by the street-side LEDs is reflected by the flat wall opposite the light guide 50 and directed and exited by the angled top surface and dots 26.

FIG. 13 is a top view of a flat (non-wedge) light guide 56 angled with respect to the street so that the front side surface is at an angle of 45 degrees to the street. The strips of LEDs 58 and 60 are positioned along the adjacent sides of the light guide 56 on the residential side. The light from the LEDs is directed towards the street. In order to direct the light downwards and sideways into the street, an array of prisms 62 shown in FIG. 14 is formed on the back of the optical guide 56 to direct the light rays 63 towards the street. This position of the LED 58/60 strip mainly controls the directivity towards the street and away from the residential side. Some light is reflected back at the opposite edge of the light guide 56, creating a small residential side radiation. The angle of the prism wall can be controlled to create the asymmetric light intensity distribution or other desired distribution of FIGS. 2 and 3. Gaussian dots may be printed on the light emitting surface of the light guide 56.

FIG. 15 shows the general luminaire of FIG. 4, but the LED segments 64 are controlled by their brightness by selecting different currents for the segment 64 using the current control circuit 66. The circuit 66 may be a passive circuit (eg, a resistor or metal interconnect pattern) or a device that can be electronically controlled to achieve the desired light intensity distribution of the luminaire. good.

Instead of mounting the LED around the edge of the optical guide, either separated by voids or more directly photocoupled, it is formed near the perimeter of the optical guide, for example, as shown in FIGS. 16 and 17. The LED on the flexible circuit may be positioned in the hole. In one embodiment, the LED 74 (FIG. 17) may be arranged in a plurality of segments in the same manner as that shown in FIG. The flexible circuit 76 that supports the LED 74 is formed in a ring shape. The reflective ring 78 is positioned over the hole 70 and can also cover the light guide 72. The optical guide 72 may include the aforementioned groove (FIG. 8-10) and the Gaussian dot 26 to create the asymmetric light intensity distribution of FIGS. 2 and 3.

The LED 74 in the hole 70 of FIG. 17 may be a side-emitting type in which a reflective layer is formed directly on the top surface of the LED die so as to cover the phosphor layer.

Elliptical lighting fixtures are also envisioned.

Numerous other luminaire designs have been engineered using the techniques described here to produce light with a distribution that emits much more light around one arc than around the other. To. For example, if luminaires are used to illuminate narrow sidewalks and are placed only about 1 foot from the ground, they may be relatively small (eg 4 inches in diameter) and they are very wide. It can have a light intensity distribution that has narrow lateral radiation and much shorter forward radiation for narrow sidewalks and basically has no residential side radiation. Similar luminaires may be used to illuminate the room to place accents on the wall more evenly, allowing the light to spread more evenly along the wall.

Although specific embodiments of the present invention have been illustrated and described, modifications and modifications can be made without departing from the invention in a broader manner, as will be apparent to those skilled in the art, and therefore, attached. Claims should include, within their scope, all modifications and modifications that fall within the true spirit and scope of the invention.

Claims (13)

It ’s a lighting system.
An optical guide configured to receive light from a plurality of light emitting diodes, wherein the plurality of light emitting diodes are located close to the outer periphery of the optical guide.
Have,
The outer circumference includes the first outer peripheral position and includes the first outer peripheral position.
The received light can be guided as guide light in the light guide.
The light guide has a light emitting surface, which is configured to allow at least a portion of the guide light to exit the light guide through the light emitting surface.
The light guide has a reflective surface on the opposite side of the light emitting surface.
The reflective surface is configured to reflect at least a portion of the guide light so that the reflected portion remains within the light guide as guide light.
The reflective surface comprises a plurality of grooves extending parallel to each other along the reflective surface.
Each groove extends into the reflective surface and
Each groove comprises a first surface tilted towards the first peripheral position at its angled surface tilt angle.
Each groove comprises a second surface adjacent to the first surface and oriented orthogonal to the light emitting surface.
The plurality of grooves increase in depth as the distance from the first outer peripheral position increases.
The angled surface tilt angle changes so that the acute angle between the first surface and the second surface decreases as the distance from the first outer peripheral position increases.
The second surface is configured to reflect light away from the first outer peripheral position so that most of the light emitted from the light emitting surface is oriented away from the first outer peripheral position. Has been,
Lighting system. The light emitting surface contains a plurality of Gaussian diffusion dots printed on the light emitting surface, and each Gaussian diffusion dot contains a plurality of microbeads arranged in an epoxy-based material, wherein the microbeads are the epoxy. It has a refractive index different from that of the system material.
The lighting system according to claim 1. The lighting system further includes a reflector disposed adjacent to and parallel to the reflective surface, which allows guide light exiting the light guide through the reflective surface to the reflective surface. The lighting system according to claim 1, which is configured to reflect back toward. The illumination according to claim 1, further comprising the plurality of light emitting diodes arranged close to the outer periphery of the optical guide and configured to direct light into the optical guide so as to form the guide light. system. The plurality of light emitting diodes are divided among a plurality of individual segments around the outer circumference of the optical guide, and the first of the individual segments and the second of the individual segments. But contains a different number of light emitting diodes,
The lighting system according to claim 4. The plurality of light emitting diodes are divided among a plurality of individual segments around the outer circumference of the optical guide.
The light emitting diodes in each of the individual segments are electrically connected in series, and the plurality of individual segments are electrically connected in parallel.
The lighting system according to claim 4. The plurality of light emitting diodes are divided among a plurality of individual segments around the perimeter of the optical guide, and the lighting system further comprises a controller configured to power the individual segments. The controller supplies the first of the individual segments with a first current and supplies the second of the individual segments with a second current different from the first current. Is configured as
The lighting system according to claim 4. The first of the individual segments and the second of the individual segments contain the same number of light emitting diodes.
The first current operably establishes a first luminance in the first segment, and the second current operably differs from the first luminance in the second segment. Establish the brightness of 2,
The lighting system according to claim 7. It ’s a way to radiate light,
The light from the plurality of light emitting diodes is received by the optical guide, the plurality of light emitting diodes are located close to the outer periphery of the optical guide, and the outer periphery includes the first outer peripheral position.
The received light is used as a guide light to guide the light in the light guide.
At least a portion of the guide light is guided out of the light guide through the light emitting surface of the light guide.
At least a part of the guide light is reflected by the reflection surface of the light guide, the reflection surface is located on the opposite side of the light emitting surface, and the reflected portion remains in the light guide as guide light.
Have that
The reflective surface comprises a plurality of grooves extending parallel to each other along the reflective surface.
Each groove extends into the reflective surface and
Each groove comprises a first surface tilted towards the first peripheral position at its angled surface tilt angle.
Each groove comprises a second surface adjacent to the first surface and oriented orthogonal to the light emitting surface.
The plurality of grooves increase in depth as the distance from the first outer peripheral position increases.
The angled surface tilt angle changes so that the acute angle between the first surface and the second surface decreases as the distance from the first outer peripheral position increases.
The second surface is configured to reflect light away from the first outer peripheral position so that most of the light emitted from the light emitting surface is oriented away from the first outer peripheral position. Has been,
Method. It ’s a lighting system.
A light guide with a circular circumference and
A plurality of light emitting diodes located close to the outer periphery of the optical guide and configured to direct the light into the optical guide toward the center of the optical guide as guide light.
Have,
The outer circumference includes the first outer peripheral position and includes the first outer peripheral position.
The light guide has a light emitting surface, which is configured to allow at least a portion of the guide light to exit the light guide through the light emitting surface.
The light guide has a reflective surface on the opposite side of the light emitting surface.
The reflective surface is configured to reflect at least a portion of the guide light so that the reflected portion remains within the light guide as guide light.
The reflective surface comprises a plurality of grooves extending parallel to each other along the reflective surface.
Each groove extends into the reflective surface and
Each groove comprises a first surface tilted towards the first peripheral position at its angled surface tilt angle.
Each groove comprises a second surface adjacent to the first surface and oriented orthogonal to the light emitting surface.
The plurality of light emitting diodes are divided among a plurality of individual segments around the outer circumference of the optical guide.
The first of the individual segments is configured to produce light with the first luminance.
A second of the individual segments is configured to produce light with a second luminance different from the first luminance.
The plurality of grooves increase in depth as the distance from the first outer peripheral position increases.
The angled surface tilt angle changes so that the acute angle between the first surface and the second surface decreases as the distance from the first outer peripheral position increases.
The second surface is configured to reflect light away from the first outer peripheral position so that most of the light emitted from the light emitting surface is oriented away from the first outer peripheral position. Has been,
Lighting system. The lighting system according to claim 10, wherein the first of the individual segments and the second of the individual segments contain different numbers of light emitting diodes. 10. The lighting system of claim 10, further comprising a controller configured to power the plurality of individual segments. The controller further supplies a first current to the first of the individual segments and a second current of the individual segments that is different from the first current. Configured to
The first of the individual segments and the second of the individual segments contain the same number of light emitting diodes.
The first current operably establishes the first luminance in the first segment, and the second current operably establishes the second luminance in the second segment. ,
The lighting system according to claim 12.

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