LED filament lamp providing polarized light

Abstract

The field of the invention is an LED filament lamp (7) for illumination, wherein at least one LED filament lamp (7) is configured to emit polarized light. The LED filament lamp (7) comprises at least one LED filament (1) and an encapsulation volume (V) with an enclosure (10), the enclosure (10) comprising a light exit window, inside which the LED filament (1) is arranged. The LED filament (1) or the LED filament (11, 12) comprises a plurality of LEDs (3) arranged on a filament carrier (2). At least one polarizer (5) is arranged relative to the LED filament (1). The polarizer (5) is configured to provide a polarization direction of the light. The polarizer (5) surrounds or partially surrounds the at least one LED filament (1) such that light or part of light emitted from the LED filament lamp (7) may be polarized light or non-polarized light.

Description

Technical Field

[0001] The invention relates to an LED filament lamp for emitting polarized light. Background Art

[0002] US2015 / 101246 A1 discloses a lighting device for plant cultivation, comprising a unit configured to convert light in any wavelength range between 300 nm and above and 600 nm and below (e.g., wavelengths between 452 nm and 474 nm) into light in a wavelength range primarily having a right-handed circularly polarized light component. This lighting device can illuminate with light that produces specific effects in plant cultivation. Thus, this lighting device is essentially an LED lamp that provides polarized light.

[0003] A trend in the lighting sector is the use of LED filament bulbs. These can be used in retrofit scenarios, such as in a typical LED lamp designed to resemble a traditional incandescent bulb with a visible filament for aesthetics and light distribution, while retaining the high efficiency of light-emitting diodes. Decorative bulbs are particularly challenging to replicate when using LEDs, as spiral filament bulbs, for example, often lack a realistic feel. Users often dislike the light emitted by LED filament bulbs compared to the well-known traditional Edison bulb. Summary of the Invention

[0004] It is an object of the present invention to overcome this problem by improving the performance and / or appearance of light emitting diode (LED) filament lamps.

[0005] According to a first aspect of the present invention, this and other objects are achieved by presenting an LED filament lamp for providing polarized LED filament light, wherein the LED filament lamp comprises:

[0006] an LED filament having a plurality of LEDs arranged on a filament carrier, wherein the LED filament is configured to emit LED filament light, and wherein the LED filament is configured to be arranged in an LED filament lamp,

[0007] light exit window, and

[0008] A polarizer completely or partially surrounds the LED filament, wherein the polarizer is configured to polarize at least a portion of the LED filament light into polarized LED filament light, such that at least a portion of the polarized LED filament light is emitted through the light exit window as polarized LED filament lamp light.

[0009] LED filament lamps, also referred to as LED filament light bulbs, are LED lamps designed to resemble traditional incandescent light bulbs, with a visible filament for aesthetic and light distribution purposes. LED filament lamps offer high efficiency when using LEDs or any solid-state lighting technology. LED filament lamps can easily replace traditional filament bulbs because they can be configured with a similar envelope shape and base to traditional filament bulbs. Furthermore, LED filament lamps can operate with multiple different supply voltages, which can be predetermined for the application. LED filament lamps can provide angles of light distribution similar to those of traditional filament bulbs.

[0010] An LED filament includes a plurality of LEDs arranged on a filament carrier. The LED filament may be elongated and have a longitudinal axis. The filament carrier is configured to carry the plurality of LEDs. The LEDs may be connected to the filament carrier along a direction of the filament carrier. The filament carrier may be a plate having first and second sides. The LEDs may be arranged on the first side of the filament carrier plate, or the LEDs may be arranged on both sides of the plate. The LEDs may be electrically connected to a power source via the filament carrier.

[0011] The LEDs may be electrically connected to a power source via electrical connections along the carrier.The elongated filament carrier may include LEDs electrically connected in strings of LEDs in series and / or parallel such that the LEDs may be similar in appearance to, for example, a filament of an incandescent light bulb.

[0012] A polarizer having a polarization direction is positioned such that the polarizer surrounds or partially surrounds the filament carrier and the plurality of LEDs, such that light emitted from the LED filament is at least partially polarized. The polarizer may surround at least 60% of the LED filament. Preferably, at least 70% of the polarizer may surround the LED filament. More preferably, at least 80% of the polarizer may surround the LED filament. Most preferably, at least 90% of the polarizer may surround the LED filament. Alternatively, the LED filament may be completely surrounded by the polarizer.

[0013] The term "polarized LED filament light" is intended to mean that the light exiting the light exit window is polarized light or substantially polarized light. Substantially polarized light means that in the operating mode, at least 90% of the light exiting the light exit window is polarized light. The light exiting the light exit window may preferably be at least 95% polarized light. More preferably, at least 98% of the light exiting the light exit window is polarized light. Most preferably, at least 99% of the light exiting the light exit window is polarized light, for example, 100% of the light exiting the light exit window is polarized light.

[0014] The polarizer can be arranged in a position relative to the LED filament such that the polarizer passes light or a portion of light from the LED of a particular polarization while blocking other polarizations in the light emitted from the LED.

[0015] The polarized light may have a first polarization direction relative to the longitudinal direction of the LED filament lamp. Alternatively, the polarized light may have a second polarization direction relative to the longitudinal direction of the LED filament lamp, wherein the second polarization direction is different from the first polarization direction.

[0016] A first polarizer providing a first polarization direction and a second polarizer providing a second polarization direction can be arranged relative to the LED filament. The first polarization direction can be different from the second polarization direction. In another embodiment, the first polarization direction can be substantially equal to the second polarization direction. In this manner, a large portion of the first LED filament is covered by the one or more polarizers. The filament carrier can be rigid, for example, made of glass, metal, quartz, sapphire, etc. Alternatively, the filament carrier can be substantially flexible, such that the filament can be bendable. The filament carrier can be light-transmissive, which provides a translucent reflection through the carrier, which can provide a decorative effect when the LED filament emits light.

[0017] In an embodiment of the present invention, an LED filament includes an elongated encapsulant covering or encapsulating a plurality of LEDs, the encapsulant including a luminescent material configured to at least partially convert LED light emitted by the plurality of LEDs into converted light.

[0018] The LED filament may be a filament carrier provided with an encapsulation. The LED filament includes an elongated encapsulation covering or encapsulating a plurality of LEDs. The encapsulation may include a luminescent material, wherein the luminescent material may be configured to at least partially convert LED light emitted by the plurality of LEDs into converted light.

[0019] In an embodiment of the invention, the polarizer is a reflective polarizer.

[0020] The reflective polarizer can be arranged as a tubular cover that surrounds or partially encloses the filament carrier with an encapsulation. The filament carrier can be an elongated filament carrier provided with an elongated encapsulation. The reflective polarizer can, for example, be bonded to the encapsulation. The reflective polarizer can be a circular or polygonal polarizer, such that it transmits the desired polarization and reflects the remaining light in another direction.

[0021] In an embodiment of the invention, the polarizer is a flexible reflective polarizer.

[0022] The polarizer can be formed as a substantially tight tube surrounding a filament carrier having an elongated encapsulation. The polarizer can be a flexible reflective polarizer. Depending on the orientation of the flexible reflective polarizer, the reflection of light can be arranged differently to change the intensity or contrast of light emitted from the LED filament lamp.

[0023] A flexible polarizer can be attached to the encapsulation. The flexible polarizer can be a flexible reflective polarizer. The flexible reflective polarizer can, for example, be bonded to the encapsulation. Alternatively, the polarizer can be, for example, a film wrapped around the elongated encapsulation. At least one polarizer can be arranged in a spiral arrangement relative to the elongated filament carrier including the elongated encapsulation. The polarizers can be arranged in the spiral arrangement such that a portion of the light emitted from the LED filament lamp is polarized light.

[0024] In another embodiment of the invention, a quarter wave plate is arranged relative to the polarizer.

[0025] A quarter-wave plate can be positioned relative to the polarizer; the quarter-wave plate can be positioned alongside the polarizer. Alternatively, the quarter-wave plate can be positioned around the polarizer to produce circularly polarized light. Quarter-wave foil can be used as an alternative to the quarter-wave plate. This provides a decorative effect when the LED filament emits light, for example when a reflective polarizer is used. Cholesteric effects can also be achieved when liquid crystals are used, for example.

[0026] In yet another embodiment of the present invention, the LED filament is a linear LED filament, wherein the polarizer is arranged in a bent position at least partially surrounding the linear LED filament.

[0027] The LED filament can be a linear LED filament having a longitudinal orientation. The polarizer can be arranged in a curved position at least partially surrounding the linear LED filament. The linear elongated filament carrier can be included in the long string of LED filaments. The filament carrier can include a carrier plate. The linear elongated carrier plate can include a plurality of LEDs mounted in a long row on a first side of the elongated carrier plate. Alternatively, the plurality of LEDs can be mounted in a long row on both or all sides of the elongated carrier plate, emitting light substantially around the elongated carrier plate.

[0028] The elongated filament carrier can be shaped as a curved filament carrier, or the filament carrier can include a curved portion. The curved LED filament can, for example, be shaped as a helically curved LED filament arranged in a helical arrangement relative to the longitudinal axis of the LED filament lamp. The curved filament carrier can be used to enhance the decorative effect of the LED lamp or LED filament lamp.

[0029] In yet another embodiment of the invention, the LED filament has a spiral or helical shape, and wherein the polarizer is arranged in a position relative to the spiral or helical shape of the LED filament, or wherein the polarizer is arranged in a bent position at least partially surrounding the LED filament.

[0030] The curved, elongated LED filament can, for example, be shaped as a helically curved LED filament arranged in a spiral arrangement relative to the longitudinal axis of the LED filament lamp. The curved LED filament arranged in the LED filament can provide a predetermined visual lighting effect during use. The curved LED filament can include a flexible polarizer or a flexible reflective polarizer. Because it is flexible only in a first direction, the flexible polarizer or flexible reflective polarizer can be arranged in a helical manner around the helically curved LED filament. Alternatively, the polarizer can be arranged in the middle of the helically curved LED filament, such that the helically curved LED filament is arranged in a helical manner around the polarizer. The LED filament lamp can include at least one curved LED filament or a partially curved LED filament.

[0031] In another embodiment of the present invention, an LED filament lamp includes a base cap for electrically and mechanically connecting the LED filament lamp to a socket of a lamp fixture, wherein the LED filament lamp includes an enclosure enclosing a volume, wherein the LED filament and the polarizer are disposed in the volume.

[0032] The LED filament includes at least one electrical connection that can be electrically connected to a power source. The LED filament may also include a mechanical connection so that the LED filament can be attached to a lamp or a base cap of a socket for the lamp. The control device may include an LED driver. The electrical connection may be connected to the LED driver and / or the control device. The control device may control the LED driver, which is driving the LEDs included in the one or more LED filaments. The control device is electrically connected to the elongated LED filament and is configured to vary the luminous flux emitted from the LED filament. The control device may control the luminous flux from at least one LED filament. By individually controlling the luminous flux, reflections of the LED filament light on the cover surface of the LED filament lamp may be reduced to improve visibility of the LED filament, or to enhance the flame-like appearance, depending on the intended application in which the LED filament lamp is to be used.

[0033] The LED driver and / or control device can be located in a base housing, which can be completely or partially arranged in a base cap. The base cap can be adapted to receive a socket. The socket can supply power to the LED filament within the LED filament lamp.

[0034] The LED filament lamp comprises an enclosure enclosing a volume, wherein the LED filament and / or the polarizer are arranged in the volume.The enclosure may comprise one or more light exit windows.

[0035] The polarizer can be fixed at a predetermined position within the enclosure. The LED filament lamp includes an enclosure, wherein the LED filament is arranged in a volume. The LED filament lamp can include a polarizer arranged in the volume, wherein the polarizer can be attached to an inner surface of the enclosure. The polarizer can be attached to an inner surface of a light exit window included in the enclosure. The polarizer can, for example, be easily bonded or otherwise fixed to the inner surface of the enclosure.

[0036] In another embodiment of the present invention, the polarizer has a cylindrical shape.

[0037] The envelope of the LED filament lamp can have a tubular shape. The polarizer can have a cylindrical shape so that the polarizer can be easily assembled into the tubular envelope. A portion of the envelope can be a tubular or semi-tubular light exit window. The polarizer can be attached to the inner surface of the envelope. The polarizer can be attached to the inner surface of the envelope, which can be the light exit window. Tubular light sources are commonly used in street lighting, flood lighting, warehouses and other commercial applications where high light output and efficiency are required. The LED filament can be arranged in a predetermined position within the envelope. When in use, the tubular envelope can provide a predetermined visual lighting effect. The LED filament lamp can provide light emitted in at least one direction perpendicular to the longitudinal direction of the tubular envelope. The polarized LED filament light is emitted through the light exit window as polarized LED filament light.

[0038] An LED filament lamp can be used for lighting and / or decorative effects. The LED filament lamp can be arranged in a socket in a lamp fixture. Alternatively, the LED filament lamp can be arranged in the socket such that the LED filament lamp is the lamp fixture. The LED filament lamp includes an encapsulation volume having an enclosure. The LED filament lamp includes at least one LED filament, wherein at least one of the at least one LED filament is an elongated LED filament. The LED filament lamp can be a retrofit LED filament lamp. The LED filament lamp can include a base cap for a retrofit socket or a standardized socket.

[0039] The LED filament lamp may include an elongated envelope providing a longitudinal axis for the LED filament lamp. The LED filament is arranged in a predetermined position within the packaging volume. The LED filament may be configured to emit polarized light having a polarization direction.

[0040] In one embodiment of the present invention, the longitudinal axis of the LED filament is arranged in an angled position relative to the longitudinal axis of the LED filament lamp, wherein the polarization direction of the polarized LED filament light is non-parallel and non-perpendicular to the longitudinal axis of the LED filament.

[0041] The LED filament can be an elongated LED filament having a longitudinal axis. The elongated LED filament can be arranged within the package volume of the LED filament lamp. The elongated LED filament can be configured to emit polarized light. The elongated LED filament emits polarized light relative to the longitudinal axis of the elongated LED filament. The longitudinal axis of the elongated LED filament can be arranged in a position that is not parallel or perpendicular to the longitudinal axis of the LED filament lamp. Alternatively, the polarization direction of the polarized LED filament light can be parallel or perpendicular to the longitudinal axis of the LED filament.

[0042] The LED filament is arranged in an angled position relative to the longitudinal axis of the LED filament lamp. The angled position can be 20 degrees to 70 degrees relative to the longitudinal axis of the LED filament lamp. The angled position can be 25 degrees to 60 degrees relative to the longitudinal axis of the LED filament lamp. The angled position can be 30 degrees to 60 degrees relative to the longitudinal axis of the LED filament lamp.

[0043] The longitudinal axis of the elongated LED filament can be arranged parallel to the longitudinal axis of the LED filament lamp, such that the LED filament emits polarized light along a first polarization direction. The elongated LED filament can be arranged at an angle relative to the longitudinal axis of the LED filament lamp, such that the LED filament emits polarized light along a second polarization direction. The second polarization direction is different from the first polarization direction. At least 80% of the light from the LED filament can be linearly or circularly polarized light. Preferably, at least 85% of the light from the LED filament can be linearly or circularly polarized light. More preferably, at least 90% of the light from the LED filament can be linearly or circularly polarized light. Most preferably, at least 95% of the light from the LED filament can be linearly or circularly polarized light.

[0044] The LED filament lamp may include at least one elongated LED filament arranged in a position at an angle relative to a longitudinal axis of the LED filament lamp. The LED filament lamp may include displacement of the elongated LED filament relative to the longitudinal axis of the LED filament lamp. The LED filament may have a longitudinal axis that, when the LED filament is displaced, is arranged at an angle relative to the longitudinal axis of the LED filament lamp. The polarization direction of a polarizer arranged relative to the LED filament may also be arranged such that the polarization direction is at an angle of + / - 90°. In this manner, the polarization direction may be parallel or perpendicular to the longitudinal axis of the LED filament lamp.

[0045] In another embodiment of the present invention, wherein the LED filament lamp comprises an encapsulant, wherein the encapsulant is disposed relative to the LED filament, and wherein the polarizer is in optical contact with the encapsulant.

[0046] The LED filament can be surrounded or partially surrounded by an encapsulant. The polarizer can be positioned in a predetermined position relative to the LED filament and / or the encapsulant such that the encapsulant is in optical communication with the encapsulant. The predetermined position of the polarizer relative to the encapsulant can be provided to optimize the optical performance of the LED filament lamp.

[0047] The encapsulant may be luminescent. The encapsulant may include more or less luminescent material. The encapsulant is configured to fully or partially surround a plurality of LEDs or a portion of these LEDs. The luminescent encapsulant is configured to convert the LED filament light into converted light. The encapsulant may be an elongated encapsulant. A hole or portion of the encapsulant may include luminescent material such that the light from the LED is fully or partially converted. One or more polarizers may fully or partially surround the elongated encapsulant such that the light or a portion of the light emitted from the LED filament is polarized light. The converted light is transmitted through the polarizer into converted polarized light and then emitted from the LED filament lamp.

[0048] In yet another embodiment of the present invention, the polarizer is arranged at a predetermined distance from the LED filament.

[0049] The polarizer can be arranged at a predetermined distance from the LED filament that is not zero. The distance between the polarizer and the LED filament can be at least 3 mm. The distance between the polarizer and the LED filament can be greater, preferably at least 6 mm. More preferably, the distance between the polarizer and the LED filament can be at least 10 mm. Most preferably, the distance between the polarizer and the LED filament is at least 15 mm, for example, 20 mm. For example, the LED filament is located at the center of the LED filament lamp, and the polarizer is attached to the inner surface of the enclosure. This provides a distance between the polarizer and the LED filament.

[0050] In yet another embodiment of the present invention, an LED filament lamp includes at least one of an LED filament configured to emit light having a first polarization direction parallel to a longitudinal axis of the first LED filament lamp and at least one additional LED filament configured to emit light having a second polarization direction perpendicular to the longitudinal axis of the LED filament lamp, and wherein the LED filament lamp includes a controller for individually controlling the LED filament and the additional LED filament.

[0051] The controller is capable of individually controlling the LED filaments during use. A predetermined distance between the polarizer and the LED filaments can be provided to optimize the optical performance of the LED filament lamp. By individually controlling the LED filaments, the optical performance of the LED filament lamp can be varied during use.

[0052] The LED filament lamp may include at least two elongated LED filaments. The first elongated LED filament and the second elongated LED filament may be arranged parallel to or at an angle to each other. The first elongated LED filament and the second elongated LED filament are also arranged relative to the longitudinal axis of the LED filament lamp. The first elongated LED filament may include a first polarizer that provides a first polarization direction. The second elongated LED filament may include a second polarizer that provides a second polarization direction. The second polarization direction may be similar to the first polarization direction. Alternatively, the second polarization direction may be different from the first polarization direction. The LED filament includes an electrical connection that is connected to a control device located within a base housing. The base housing can be attached to a base cap for a socket.

[0053] By individually controlling the reflection of the first and second LED filaments, the reflection of the LED filament light on the cover surface of the LED filament lamp can be reduced to improve the visibility of the LED filament and / or enhance the flame-like appearance. The reflection depends on the intended application in which the LED filament lamp will be used.

[0054] The LED filament lamp can be controlled such that in a first operating mode, only one or more first LED filaments providing p-polarized light are electrically activated, and in a second operating mode, only one or more second LED filaments providing s-polarized light are electrically activated. When the LED filaments are electrically controlled, the LED filament lamp can switch between p- and s-polarized light.

[0055] In another example, the LED filament lamp can be controlled so that in a first operating mode, only one or more first LED filaments providing p-polarized light are electrically activated, or only one or more second LED filaments providing s-polarized light are electrically activated. In a second operating mode, the LED filament lamp can be controlled so that both the first and second LED filaments are electrically activated simultaneously. In this way, the LED filament lamp can switch between polarized light (i.e., p- and s-polarized light) and unpolarized light.

[0056] In yet another embodiment of the present invention, an LED filament lamp includes a first LED filament having a first longitudinal direction and a second LED filament having the first longitudinal direction, wherein the first and second LED filaments have similar polarizers such that light emitted from each LED filament has the same polarization direction, wherein the first and second LED filaments are arranged at an angle β relative to the first and second longitudinal directions of the respective LED filaments, wherein the angle β is in a range of 15 degrees to 80 degrees, and wherein the light emitted from each LED filament has the same polarization direction.

[0057] The LED filament lamp includes at least two elongated LED filaments. An angle β defines the angle between the first and second longitudinal axes of each LED filament. Each LED filament can be provided with a respective polarizer. The first and second LED filaments have similar polarizers such that light emitted from each LED filament has the same polarization direction. Each LED filament can be arranged at an angle β relative to the longitudinal axis of each LED filament lamp, and the angle can be different from 0°. Alternatively, the longitudinal axis of each LED filament or one of the LED filaments can be arranged at an angle β different from 0° relative to the corresponding longitudinal axis of the other LED filament. The first and second LED filaments are arranged at an angle β relative to the first and second longitudinal axes of the respective LED filaments, wherein the angle β can be in the range of 15 degrees to 80 degrees. The light emitted from each LED filament has the same polarization direction.

[0058] Alternatively, the longitudinal axis of the first LED filament can be arranged in a position parallel to the longitudinal axis of the LED filament lamp, wherein the LED filament emits polarized light along a first polarization direction. The longitudinal axis of the second LED filament can be arranged in a position at an angle relative to the longitudinal axis of the LED filament lamp, wherein the second LED filament emits polarized light along a second polarization direction. The second polarization direction is different from the first polarization direction.

[0059] LED lamps provided with LED filaments as described above provide enhanced designs to resemble traditional incandescent light bulbs for aesthetic and light distribution purposes, with the high efficiency of LEDs. In particular, decorative bulbs resemble traditional spiral bulbs without lacking authenticity.

[0060] The present invention also relates to a luminaire comprising at least one LED filament lamp according to the present invention.

[0061] The LED filament lamp can be arranged in the lamp, wherein the LED filament lamp can be used for lighting and / or decorative effects. The LED filament lamp can produce direct or indirect lighting effects. The lamp may include a socket, wherein the socket is configured to receive a base cap of the LED filament lamp.

[0062] It is noted that the invention relates to all possible combinations of features recited in the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] This and other aspects of the present invention will now be described in more detail, with reference to the appended drawings showing embodiment(s) of the invention.

[0064] Figure 1a and Figure 1b Cross-sectional side views of different embodiments of an elongated LED filament of an LED lamp according to the present invention are shown.

[0065] Figure 2 A cross-sectional view of an embodiment of an LED filament lamp according to the present invention and comprising an elongated LED filament is shown.

[0066] Figure 3 A cross-sectional view of an embodiment of an LED filament lamp according to the present invention and comprising two elongated LED filaments is shown.

[0067] Figure 4 A cross-sectional view of an embodiment of an LED filament lamp according to the present invention and including a displaced elongated LED filament is shown.

[0068] Figure 5 A cross-sectional view of an embodiment of an LED filament lamp according to the present invention and comprising a helically bent elongated LED filament is shown.

[0069] As shown in the figures, the sizes of layers and regions are exaggerated for illustrative purposes and are therefore provided to illustrate the general structure of embodiments of the present invention. Like reference numerals refer to like elements throughout. DETAILED DESCRIPTION

[0070] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which presently preferred embodiments of the invention are shown. However, the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so as to be thorough and complete and to fully convey the scope of the invention to those skilled in the art.

[0071] Figure 1a and Figure 1b An embodiment of an elongated LED filament 1 for an LED lamp 7 according to the present invention is shown. The elongated LED filament 1 includes a plurality of LEDs 3 arranged on an elongated filament carrier 2. The elongated filament carrier 2 is formed as a linear elongated filament carrier 2. An elongated encapsulant 4 is configured to cover or partially cover the plurality of LEDs 3 or a portion of the LEDs 3. The elongated encapsulant 4 may include a luminescent material such that light from the LEDs 3 is converted or partially converted into converted light. For example, the LEDs 3 may emit in the blue wavelength range, and the luminescent material may include a phosphor material such that the converted light is white light. The converted light is transmitted through a polarizer 5 into converted polarized light, which is emitted from the elongated LED filament 1.

[0072] At least one polarizer 5 comprising a polarization direction surrounds or partially surrounds the elongated encapsulant 4 so that light or part of the light emitted from the elongated LED filament 1 is polarized light.

[0073] The elongated LED filament has a longitudinal axis X extending from the first electrical connection 6 to the 1 Extending to the second electrical connection 6 2The LED 3 can be connected to the electrical connector 6 1 , 6 2 and is electrically connected to a power source.

[0074] The elongated filament carrier 2 is configured to carry an LED 3. The LED 3 is attached to the filament in the direction of the filament carrier 1. The LED 3 is arranged on a first side of the elongated filament carrier 2. The LED 3 provides a substantially semi-cylindrical illumination with polarized light.

[0075] Figure 1a The first and second embodiments of the elongated LED filament 1 are shown. The first embodiment of the elongated LED filament 1 ( Figure 1a The left-hand side of the LED filament 1 comprises a polarizer 5 which provides a first polarization direction P parallel to the longitudinal axis X of the elongated LED filament 1. 1 (Indicated by arrows) of polarized light. The second embodiment of the second elongated LED filament 1 ( Figure 1a The right-hand side of the LED filament 1 comprises a polarizer 5 which provides a second polarization direction P having an angle non-zero with the longitudinal axis X of the elongated LED filament 1. 2 (As shown by the arrow) polarized light. The second polarization direction P 2 Different from the first polarization direction P 1 The elongated LED filament 1 can be integrated into an LED filament lamp or the like. 1 With respect to the second polarization direction P 2 Orientation can reduce reflection of the LED filament light on the cover surface of the LED filament lamp to improve visibility of the LED filament 1, or can enhance the flame-like appearance, depending on the intended application in which the LED filament lamp is used.

[0076] Figure 1b Three different cross-sectional shapes of the elongated LED filament 1 are shown. The elongated filament carrier 2 may be an elongated carrier plate sealed by an encapsulant. The polarizer 5 is arranged as a cross-sectional tubular cover that surrounds or partially encloses the elongated filament carrier 2 with the elongated encapsulant, see Figure 1b Alternatively, the polarizer may have a cross-sectional shape of a circular or polygonal cap, see Figure 1b Furthermore, the polarizer may have a cross-sectional shape provided by first and second flat elongated polarizers 5 arranged on opposite sides of the elongated filament carrier 2, see Figure 1b The first and second polarizers 5 may have different polarization directions.

[0077] Figure 2An embodiment of an LED filament lamp 7 including an elongated LED filament 1 is shown. The LED filament lamp 7 is a retrofit lamp for lighting. The LED filament lamp 1 includes a packaging volume V having a cover surface 10. The LED filament lamp 7 has a longitudinal axis LA. The elongated LED filament 1 is arranged within the packaging volume V and extends parallel to the longitudinal axis LA of the LED filament lamp 7. The elongated LED filament 1 is configured to emit light having a polarization direction P, which is indicated by an arrow.

[0078] The LED filament 1 comprises an electrical connection 6 which is electrically connected to an LED driver 8 which is electrically connected to a base 9 for a socket. The LED filament 1 may also comprise a mechanical connection so that the LED filament can be attached to the housing of the LED driver 8.

[0079] Figure 3 The LED filament 1 includes two elongated LED filaments. 1 、1 2 An embodiment of an LED filament lamp 7. A first elongated LED filament 1 1 and the second slender LED filament 1 2 Arranged parallel to each other. The first elongated LED filament 1 1 and the second slender LED filament 1 2 The first elongated LED filament 1 is also arranged parallel to the longitudinal axis LA of the LED filament lamp 7. 1 A first polarizer is included, which provides a first polarization direction P as shown by the arrow 1 The second slender LED filament 1 2 A second polarizer is included, which provides a second polarization direction P as shown by the arrow 2 The second polarization direction P 2 Different from the first polarization direction P 1 LED filament 1 1 、1 2 Each comprises electrical connections which are connected to a control 11 located in a housing which is attached to a base 9 for the socket.

[0080] By individually controlling the first and second LED filaments 1 1 、1 2 The reflection of the LED filament light on the cover surface 10 of the LED filament 7 can be reduced to improve the visibility of the LED filament 1 and enhance the flame-like appearance, depending on the intended application in which the LED filament is to be used.

[0081] Figure 4 An embodiment of an LED filament lamp 7 comprising a displaced elongated LED filament 1 is shown. The longitudinal axis X of the LED filament is arranged at an angle to the longitudinal axis LA of the LED filament lamp 7. The polarization direction P of the light provided by the polarizer arranged on the LED filament 1 is arranged so that the angle is or In this way, the polarization direction P is parallel or perpendicular to the longitudinal axis LA of the LED filament lamp 7 .

[0082] Figure 5 An embodiment of an LED filament lamp 7 is shown that includes a helically bent LED filament 1. The helically bent LED filament 1 is arranged in a helical arrangement relative to the longitudinal axis LA of the LED filament lamp 7. The helically bent LED filament 1 can include a flexible polarizer or a flexible reflective polarizer 5. Because the LED filament 1 is flexible only in a first direction, the polarizer 5 can be arranged in a helical manner around the helically bent LED filament. Alternatively, the polarizer 5 can be arranged in the middle of the helically bent LED filament along the longitudinal axis LA of the LED filament lamp 7, such that the helically bent LED filament is arranged in a helical manner around the polarizer 5. Alternatively, a first polarizer can be arranged in a helical manner around the helically bent LED filament, and a second polarizer can be arranged in a helically bent LED filament along the longitudinal axis LA of the LED filament lamp 7, with the helically bent LED filament arranged in a helically manner around the polarizer.

[0083] A person skilled in the art realizes that the present invention is by no means limited to the preferred embodiments described above. On the contrary, many modifications and variations are possible within the scope of the appended claims.

[0084] Additionally, variations to the disclosed embodiments will be understood and implemented by those skilled in the art in practicing the claimed invention by studying the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not mean that a combination of these measures cannot be employed to advantage.

Claims

1. An LED filament lamp (7) for providing polarized LED filament light, wherein the LED filament lamp comprises: An LED filament (1) having a plurality of LEDs (3) arranged on a filament carrier (2), wherein the LED filament (1) is configured to emit LED filament light, and wherein the LED filament (1) is configured to be arranged in the LED filament lamp (7); A capsule (10), the capsule having a light exit window; as well as a polarizer (5) which completely or partially surrounds the LED filament (1), wherein the polarizer is configured to polarize at least a portion of the LED filament light into polarized LED filament light, so that at least a portion of the polarized LED filament light is emitted through the light exit window as the polarized LED filament light, and Wherein the polarizer is a reflective polarizer.

2. The LED filament lamp according to claim 1, wherein the LED filament comprises an elongated encapsulant (4) covering or encapsulating the plurality of LEDs, the encapsulant comprising a luminescent material configured to at least partially convert the LED light emitted by the plurality of LEDs into converted light.

3. The LED filament lamp according to claim 1 or 2, wherein the polarizer (5) is a flexible reflective polarizer.

4. The LED filament lamp according to any one of the preceding claims, wherein a quarter wave plate is arranged downstream of the polarizer (5).

5. The LED filament lamp according to any one of the preceding claims, wherein the LED filament (1) is a linear LED filament (1), wherein the polarizer (5) is arranged in a bent position at least partially around the LED filament (1).

6. The LED filament lamp according to any one of claims 1 to 4, wherein the LED filament (1) has a spiral or helical shape, and wherein the polarizer (5) is arranged as: (i) in a helical or spiral position relative to said LED filament (1), or (ii) in a bent position at least partially surrounding the LED filament (1).

7. The LED filament lamp according to any one of the preceding claims, wherein the LED filament lamp (7) comprises a base cap (9) for electrically and mechanically connecting the LED filament lamp (7) to a socket of a lamp fixture, wherein the LED filament lamp (7) comprises the enclosure (10) enclosing a volume, wherein the LED filament (1) and the polarizer are arranged in the volume.

8. The LED filament lamp according to any one of the preceding claims, wherein the polarizer (5) is attached to the inner surface of the envelope (10).

9. The LED filament lamp according to any one of the preceding claims, wherein the longitudinal axis (X) of the LED filament (1) is arranged in an angled position relative to the longitudinal axis (LA) of the LED filament lamp (7), wherein the polarization direction (P) of the polarized LED filament light is non-parallel and non-perpendicular to the longitudinal axis (X) of the LED filament (1).

10. The LED filament lamp according to any one of the preceding claims, wherein the LED filament comprises an elongated encapsulant (4) covering or encapsulating the plurality of LEDs, and wherein the polarizer (5) is in optical contact with the encapsulant (4).

11. The LED filament lamp according to any one of claims 1 to 9, wherein the polarizer (5) is arranged at a predetermined distance from the LED filament (1).

12. The LED filament lamp according to any one of the preceding claims, wherein the LED filament lamp (7) comprises the LED filament (1 1 ) and at least one additional LED filament (1 2 ), the LED filament (1 1 ) is configured to emit light having a first polarization direction (P) parallel to the longitudinal axis (LA) of the LED filament lamp (7) 1 ) of light, said at least one other LED filament (1 2 ) is configured to emit a second polarization direction (P) perpendicular to the longitudinal axis (LA) of the LED filament lamp (7) 2 ) of light, and wherein the LED filament lamp (7) includes a device for individually controlling the LED filament (1 1 ) and the additional LED filament (1 2 ) controller (8).

13. The LED filament lamp according to any one of claims 1 to 11, wherein the LED filament lamp comprises a first LED filament (1 1 ) and a second LED filament having a second longitudinal axis (1 2 ), wherein the first LED filament and the second LED filament have similar polarizers (5), so that the polarizer (5) from the LED filament (1 1 ,1 2 ) has the same polarization direction (P), wherein the first LED filament and the second LED filament are arranged at an angle β relative to the first longitudinal axis and the second longitudinal axis of the corresponding LED filament, wherein the angle β is in the range of 15 degrees to 80 degrees.

14. The LED filament lamp according to any one of the preceding claims, wherein the polarizer has a cylindrical shape.

15. A lamp for lighting, wherein the lamp comprises at least one LED filament lamp (7) according to any one of claims 1 to 14.

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