TWI475175B - Multi - color light - emitting device - Google Patents

Description

Multicolor light emitting device

The present invention relates to illumination devices and systems, and more particularly to multi-color illumination devices that employ wavelength conversion to produce high brightness polychromatic light.

High-brightness can be produced by using a solid-state light source such as a laser diode (LD) or an LED (Light Emitting Diode) to emit light and a wavelength conversion material such as a phosphor or a quantum dot wavelength conversion method. Light having a wavelength different from the wavelength of the excitation light. In a conventional device, excitation light is incident on a wavelength converting material that absorbs excitation light and produces light having a wavelength higher than the wavelength of the excitation light (excited light). In order to produce different colors, different wavelength converting materials are used.

U.S. Patent No. 7,547,114 issued to <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> </ RTI> <RTIgt; The excitation source is a light-emitting diode or a laser diode that emits light in the ultraviolet and/or blue regions. Each segment of the moving disk contains a different wavelength converting material or no wavelength converting material. The disk is set to move such that the different segments are exposed to the excitation light at different times. As the disk moves, different wavelength-converting materials of different segments on the disk continuously produce different colors of light in time. Such a multi-color illumination device can be used in a projection system having a microdisplay imager on an image display. Chinese Patent Application No. CN101858496A, which is hereby incorporated by reference, discloses a multi-color illuminating device based on wavelength conversion, which uses two light sources of different colors. Two light sources, one emitting blue light and the other emitting ultraviolet light, are placed in front of the wavelength converting material. The blue light and the ultraviolet light are guided to the rotating wavelength conversion device by the combination of the light combining means. The wavelength conversion device includes a plurality of segments carrying different wavelength converting materials (such as red and green phosphors) and a transparent segment that does not carry a wavelength converting material and is capable of transmitting blue light. Both ultraviolet and blue light can be used to excite wavelength converting materials. When the transparent segment is turned into the optical path of the incident light, the ultraviolet light is turned off and only blue light is transmitted through the transparent segment to produce blue output light. When the segment carrying the wavelength converting material is turned into the optical path of the incident light, both the blue light and the ultraviolet light are turned on to excite the wavelength converting material. An inductor is used to sense the position of the rotating wavelength conversion device and emit a signal that controls the ultraviolet light source switch.

A typical multicolor illumination system requires the generation of multiple primary colors, such as red, green, and blue light, to produce other desired light. Multicolor illumination systems may also need to produce yellow light that is mixed with blue light to produce white light. In order to produce polychromatic light using wavelength conversion, a key condition is to use a wavelength converting material that converts the excitation light into the desired light, such as red, green, blue, yellow, etc. (but the blue light source is often used directly as blue light. Not a wavelength conversion). However, different wavelength converting materials often have different efficiencies. For example, among currently available wavelength conversion materials, the efficiency and reliability of a phosphor powder material that produces red converted light (represented by red fluorescent powder for convenience) is low. For other phosphors, such as green and yellow phosphors.

Accordingly, it is desirable to provide a multi-color illumination device to address the above-discussed technical problems due to limitations and disadvantages of the prior art.

The object of the present invention is to provide a multi-color light-emitting device, which can synchronize the rotation control of the wavelength conversion device with the control of the output power of the first light source and the second light source by a control device, thereby avoiding the use of red fluorescent light. The problem of low light conversion efficiency caused by powder.

In order to achieve the above object of the present invention, the inventors of the present invention have proposed a multi-color light-emitting device comprising a first light source for emitting a first light, a second light source for emitting a second light, and a wavelength conversion device comprising at least two points. a first segment that does not carry the wavelength converting material and a second segment that carries the first wavelength converting material, the first wavelength converting material absorbs the first light and generates a third light; and the optical device is configured to guide the first And the second light is incident as incident light to the wavelength conversion device, the wavelength conversion device being movable relative to the first and second light sources such that the first and second segments are sequentially exposed in the optical path of the incident light; and the output end is used Receiving the outgoing light emitted by the wavelength conversion device.

Wherein, in the first period of time, the light originating from the first light source is allowed to be output to the output end, and the light originating from the second light source is prevented from being output to the output end; in the second time period, the light output originating from the second light source is allowed to be outputted Going to the output and preventing light originating from the first source from being output to the output; the first period of time is the second segment of the wavelength conversion device exposed to the incident light The time period in the middle of the road, the second time period is a time period when the first segment of the wavelength conversion device is exposed in the optical path of the incident light.

In addition, the inventor of the present invention also proposes another multi-color light-emitting device, including a first light source for generating a first light, the first light being blue light or ultraviolet light, and a second light source for generating a second light, the second light being a red light; a wavelength conversion device comprising at least two segments, a first segment carrying no wavelength converting material and a second segment carrying a first wavelength converting material, the first wavelength converting material absorbing the first light and generating a third light; and optical means for directing the first and second rays as incident light to the wavelength conversion device.

Wherein the wavelength conversion device is movable relative to the first and second light sources such that the first and second segments are sequentially exposed in the optical path of the incident light; further, the first light source is turned on at least for the first time period, the first time The segment is a time period when the second segment of the wavelength conversion device is exposed in the optical path of the incident light; and the second light source is turned on at least for the second time period, the second time period being exposed to the first segment of the wavelength conversion device The period of time in the optical path of the incident light.

In order to more clearly describe the multi-color illuminating device proposed by the present invention, a preferred embodiment of the present invention will be described in detail below with reference to the drawings.

1 is a schematic structural diagram of a first embodiment of a multi-color light-emitting device according to the present invention. The multi-color light-emitting device provided by the embodiment of the present invention includes a first light source 1, a second light source 2, a light combining device 3, and a wavelength. Conversion device 4. The first light source 1 is for generating an excitation light (first light), preferably, first The light is blue or ultraviolet. The second light source 2 is for generating a second excitation light (second light), and in a preferred embodiment, the second light is red light. In other embodiments, the second light may be green or other colored light. The first source and the second source may be light emitting diodes, laser diodes or other solid state light sources. The wavelength converting material carried on the wavelength conversion device 4 absorbs the first light and generates a third light.

Preferably, the second light overlaps the spectral portion of the third light, for example, when the second light is red, the third light is yellow or orange; or the second light is green, the third light is It is yellow or blue.

The light combining device 3 is placed between the wavelength conversion device 4 and the two light sources (the first light source 1 and the second light source 2), and directs the first light and the second light to the wavelength conversion device 4. As an example, the light combining device 3 is a spectral filter that reflects one of the first and second rays while transmitting the other of the first and second rays. In the typical structure shown in FIG. 1, the spectroscopic filter 3 transmits the first light emitted by the first light source 1 (as indicated by the arrow A) and reflects the second light emitted by the second light source 2 (as indicated by the arrow B). ). Specifically, the optical paths of the first light and the second light after the light combining device 3 are the same. (Not shown in Fig. 1, the arrows A and B are drawn only for the convenience of the plane representation.) Another embodiment of the light combining device 3 is a fiber bundle having a branch 埠 and a combined 埠. For convenience of description, the first light and the second light incident on the wavelength conversion device 4 after the light combining device 3 is combined will be referred to as incident light A/B.

The light combining device 3 is optional. For example, the device is not necessary in the case where the first and second light sources 1, 2 are laser, since usually the exit angle of the laser is small and can be directed to the wavelength conversion device 4 from different angles. Furthermore, if the first and second light sources are directed to the wavelength conversion device in the opposite direction, it is not necessary to use a light combining device.

In the embodiment shown in the first figure, the wavelength conversion device 4 is of a transmissive type, that is, the direction of travel of the emitted light (as indicated by the arrow C) generated by the wavelength conversion device is the same as the incident light A/B. In another embodiment, the wavelength conversion device 4 is reflective, that is, the direction of travel of the exiting light generated by the wavelength conversion device is substantially opposite or at an angle to the incident light A/B. In another embodiment, the first and second rays A, B are directed from opposite directions to the wavelength conversion device, and the wavelength conversion device is in a mixed form of transmission and reflection. For example, in one such embodiment, the first light is directed from the first direction to the wavelength conversion device, and the second light is directed from the second direction (ie, the direction opposite the first direction) to the wavelength conversion device, and the light is emitted The first direction travels (in this case, the light produced by the wavelength conversion device travels in a first direction and the wavelength conversion device reflects the second light back into the first direction). In another such embodiment, the first light is directed from the first direction to the wavelength conversion device, the second light is directed from the second direction to the wavelength conversion device, and the exiting light travels in the second direction (in this case, The light generated by the wavelength conversion device travels in a second direction and the wavelength conversion device transmits the second light to a second direction). The following detailed description focuses on the transmissive (first figure); it can be changed to implement various types of devices. The location of the various components, as well as various different or additional optical devices such as spectral filters, may be employed as part of the wavelength conversion device or suitably placed elsewhere in the optical path. The present invention covers all of these different kinds of devices. Based on the description of the present disclosure and the prior art well known in the art, alternative types of devices can be implemented without undue experimentation.

The output of the multicolor illumination device is represented by means 7. The output can be used to collect and receive the outgoing light from the wavelength conversion device 4 using any suitable optical device.

Other optical devices may be present in the illumination device but are not labeled in Figure 1, such as focusing and/or light shaping optics placed before the wavelength conversion device 4, light collection optics placed behind the wavelength conversion device, color filtering Light film and so on.

One face of the wavelength conversion device 4 contains a plurality of segments. Each segment carries a wavelength converting material that absorbs the excitation light and produces the excited light, or does not carry a wavelength converting material (described herein as "transparent"). The wavelength conversion device 4 is mounted on a support structure (not shown) and moves with it. During the movement, different segments of the wavelength conversion device sequentially fall on the optical path of the incident light A/B.

In the embodiment shown in the first and second figures, the wavelength conversion device 4 is an annular structure that is placed perpendicular to the direction of the incident light A/B and that rotates about an axis parallel to the incident light (eg, arrow D). Shown). The circumferential area of the ring of the wavelength conversion device 4 is divided into a plurality of segments in the angular direction 41-44. When the wavelength conversion device 4 is rotated, different segments are exposed to the optical path of the incident light for different periods of time.

In another alternative (not shown), the wavelength conversion device 4 is a disk comprising a plurality of segments arranged in a linear direction, moving in the linear direction in the form of a reciprocating motion. In another alternative (not shown), the wavelength conversion device 4 is a rotating cylinder comprising a plurality of segments arranged in the angular direction of the cylinder. The mechanism and electrical structure for realizing the movement of the wavelength conversion device are similar to those of the prior art in the related art.

In the preferred embodiment illustrated in FIG. 2, the wavelength conversion device 4 includes four closely spaced segments 41, 42, 43, and 44. Segments 43 and 44 are respectively carried with green and yellow wavelength converting materials that absorb light generated by the first source and emit green and yellow light, respectively. When the excitation light is blue light, the segment 42 does not carry the wavelength conversion material and transmits the excitation light; when the excitation light is ultraviolet light, the segment 42 carries the blue wavelength conversion material and is excited by the excitation light to generate blue light. The segment 41 does not carry the wavelength converting material and transmits the red light generated by the second source 2. The segment 44 carrying the yellow phosphor is optionally omitted.

A filter is optionally employed after the green and yellow segments to block residual blue or ultraviolet light. At the same time, a sufficiently thick layer of wavelength converting material can be optionally used to reduce residual blue or ultraviolet light. Alternatively, a filter that blocks ultraviolet light is used in the light path behind the color wheel.

In the first embodiment, the first and second light sources 1, 2 are based on a specific mode The mode is controlled to be turned on or off, and its on/off period is synchronized with the movement of the wavelength conversion device 4 to generate the outgoing light C having different colors at different time periods. Specifically, the first light source 1 (blue or ultraviolet excitation light) is controlled to turn on when the segments 42, 43 and 44 are turned to the optical path of the incident light, and is controlled to be turned off when the segment 41 is turned to the optical path of the incident light. The second source 2 (red directly exiting light) is controlled to turn on when the segment 41 is turned to the optical path of the incident light, and is controlled to turn off when the segments 42, 43 and 44 are turned to the optical path of the incident light. As a result, the outgoing light C collected after the wavelength conversion device 4 is blue, green, and yellow when the segments 42, 43 and 44 are turned to the optical path of the incident light, and is red when the segment 41 is turned to the optical path of the incident light. Light. In this mode, the red light generated by the second light source 3 is directly emitted as the outgoing light instead of the excitation light as the wavelength converting material.

For the transmissive wavelength conversion device 4, the transparent segments 41 and 42 are used to transmit red and blue light, respectively. For the reflective wavelength conversion device 4, the transparent segments 41 and 42 are used to reflect red and blue light, respectively.

It should be noted in the second figure that the color designation of segments 41-44 corresponds to the color of the exiting light, rather than the color of the wavelength converting material, since segments 41 and 42 may not contain wavelength converting material.

As the wavelength conversion device 4 shown in the second figure, the color sequence of the outgoing light C is red-blue-green-yellow-red-... because the four segments 41-44 are the same size, the outgoing Each color takes up about 25% of the time. Preferably, the wavelength conversion device 4 can be designed to output other desired color sequences, and/or different colors have different durations.

The control system can be used to synchronize the switching states of the first and second sources 1, 2 and the movement of the wavelength conversion device 4. As shown in the third figure, the control system includes an inductor 5 for sensing the position of the wavelength conversion device 4 and generating a signal indicative of the sensed position. Based on this signal from the sensor 5, the controller 6 can generate control signals that control the opening and closing of the first and second sources 1, 2. The controller 6 can be one unit that controls two two elements, or can be two units that respectively control two light sources.

Any suitable sensing system may be used to implement the inductor 5, and the inductor may couple the movement of the inductive wavelength conversion device 4 in any suitable manner. For example, the sensor 5 may be an optical decoder, a resolver, a Hall sensor, or the like for sensing the position of the wavelength conversion device 4. Alternatively, the sensor may be an optical sensor for sensing the color of the outgoing light C emitted by the wavelength conversion device 4 and related to the position of the wavelength conversion device.

The actual principles of switching light sources 1 and 2 may include powering the light source, or may include mechanically, optically, or otherwise optically blocking the light emitted by each source. If a shutter is used, it can be located between each of the light sources 1, 2 and the light combining means 3. The shutter can also be an integral part of the light source. Thus, the term "turning the light source on and off" can be broadly interpreted to cover any implementation that allows or prevents light from the source from reaching the wavelength conversion device 4. In actual implementation, the use of the shutter can cause waste of light energy, and the switching light source power supply has the advantage of energy saving, and is not difficult to implement, and becomes a more preferable control method.

In a particular embodiment, the sensor 5 generates a pulse signal each time the wavelength conversion device 4 is turned to a particular position, at which point the excitation light is passed at the boundary between the segment 44 (yellow) and the segment 41 (red). The light path. When the controller 6 receives the pulse from the sensor 5, the controller 6 controls the second light source to be turned on and the first light source to turn off; after a predetermined period of time, the second light source is turned off and the first light source is turned on. Then when another pulse of the sensor 5 is received, the controller turns on the second light source and turns off the first light source, and the sequence of events repeats. In one example, the rotation period of the wavelength conversion device 4 is 10 ms and the predetermined period of time is 2.5 ms.

The fourth diagram is a timing diagram of the wavelength conversion device 4, the inductor 5, and the light sources 1, 2 of the present embodiment. Lines (a)-(d) have the same time axis (arbitrary units). (a) The row indicates the movement of the wavelength conversion device 4 and the color of the emitted light of the wavelength conversion device. For example, a square labeled "R" represents a time period when the red segment 41 is in the incident light path and the red light is emitted; a square labeled "B" represents a time period when the blue segment 42 is in the incident light path and the blue light is emitted; and many more. The line (b) represents the pulse signal generated by the sensor 5. (c) Row and (d) row respectively indicate the switching states of the second light source (red light source) and the first light source (blue light source); the square labeled "R" indicates when the second light source (red light source) is turned on The segment; the square labeled "B" indicates the period of time when the first light source (blue light or ultraviolet light source) is turned on.

The timing shown in the fourth figure is only an example; other timings can also be used. For example, the pulse signal can be on the side of the red segment 41 and the blue segment 42 The boundary is generated or generated at other locations in the rotation of the wavelength conversion device 4.

5A to 5C are schematic views of the wavelength conversion device in the second, third, and fourth embodiments of the present invention. The optical arrangement in the second, third, and fourth embodiments is substantially the same as that of the first embodiment (first figure) except for the configuration of the wavelength conversion device 4. In the second, third, and fourth embodiments, a suitable spectroscopic filter can be fixed (and thus moved synchronously) with certain segments of the wavelength conversion device, thereby eliminating the need to switch the light sources 1 and 2.

Fig. 5A is a schematic diagram of the wavelength conversion device 4A of the second embodiment. The wavelength conversion device 4A includes four closely spaced segments 41A-44A. The segments 41A-44A are identical to the segments 41-44 of the first embodiment in view of whether or not the wavelength converting material is carried on the segments. However, the blue, green, and yellow segments 42A, 43A, and 44A are placed with a spectral filter that reflects the second (red) light and transmits the first (blue or ultraviolet) light. No filter is placed on the red segment 41A. With this wavelength conversion device 4A, when the blue, green, and yellow segments 42A, 43A, and 44A are turned into the optical paths of the incident lights A and B, the second (red) light source does not have to be turned off. In other words, the second (red) light source can continue to illuminate. The first (blue or ultraviolet) light source must still be turned off when the red segment 41A is turned into the optical path of incident light A and B.

Fig. 5B is a schematic diagram of the wavelength conversion device 4B of the third embodiment. The wavelength conversion device 4B includes four closely spaced segments 41B-44B. The segments 41B-44B are identical to the segments 41-44 of the first embodiment in view of whether or not the wavelength converting material is carried on the segments. However, there is a reflection placed on the red segment 41B. A first (blue or ultraviolet) ray and a spectroscopic filter that transmits a second (red) ray. No filters are placed on the blue, green, and yellow segments 42B, 43B, and 44B. With such a wavelength conversion device 4B, when the red segment 41B is turned into the optical paths of the incident lights A and B, the first (blue or ultraviolet) light source does not have to be turned off. In other words, the first (blue or ultraviolet) light source can continue to illuminate. The second (red) light source must still be turned off when the blue, green, and yellow segments 42B, 43B, and 44B are turned into the optical paths of the incident lights A and B.

The fifth C diagram is a schematic diagram of the wavelength conversion device 4C of the fourth embodiment. The wavelength conversion device 4C includes four closely spaced segments 41C-44C. The segments 41C-44C are identical to the segments 41-44 of the first embodiment in view of whether or not the wavelength converting material is carried on the segments. However, the blue, green, and yellow segments 42C, 43C, and 44C are placed with a spectroscopic filter that reflects the second (red) light and transmits the first (blue or ultraviolet) light, and has a red segment 41C placed thereon. A spectroscopic filter that reflects the first (blue or ultraviolet) light and transmits the second (red) light. With this wavelength conversion device 4C, both the first (blue or ultraviolet) light source and the second (red) light source are continuously illuminated. For the fourth embodiment, the control system including the inductor 5 and the controller 6 (third diagram) can be omitted.

In the second to fourth embodiments, the spectroscopic filter is located over the entire area of the corresponding segment. In the second and fourth embodiments, the spectroscopic filter may preferably be located on the side of the wavelength converting material facing the excitation light. The filter can also be located on one side of the outgoing light. However, in the latter structure, light loss may occur, for example. For example, the exiting light of a wavelength converting material (such as yellow light) and the second light (such as red light) have spectral overlap.

Further, if the wavelength conversion device 4A/4B/4C is of a reflective type, the spectral filtering characteristics of the filter are reversed. In other words, the spectroscopic filter for the red segments 41A/41C reflects the second (red) light and transmits the first (blue or ultraviolet) light. The spectroscopic filters for the blue, green, and yellow segments 42A/42A, 43A/43C, and 44A/44C reflect the first (blue or ultraviolet) light and transmit the second (red) light. In this configuration, the spectral filter is located on the side of the wavelength converting material that faces away from the incident light.

From the above description of the first to fourth embodiments, the functional requirements of the multicolor light-emitting device are as follows: in the "red" time period (i.e., when the red segment 41/41A/41B/41C is located in the light path of the incident light) Medium), the red light emitted by the second light source is emitted after the wavelength conversion device 4, and the blue light emitted by the first light source cannot be emitted. During the "non-red" period (ie, when the segment of the non-red segment is in the path of the incident light), the blue light emitted by the excitation light or the first source exits, and the red light from the second source cannot exit.

In a broader sense, the multi-color light-emitting device of the above-described embodiment of the present invention is characterized in that, in the first period of time (eg, the non-red period), the wavelength conversion device 4 only emits light originating from the first light (eg, the blue light itself). Or the wavelength-converting material is excited by blue light or ultraviolet light; in the second time period (such as the red time period), only light originating from the second light (such as red light itself) is emitted. The two time periods do not overlap in time. Used in the discussion of the present invention The light "derived from A" includes the light emitted by A itself, and the light emitted by A itself is excited by the excited phosphor. "Inclusion" herein is not limited to forming a mixture of light emitted by A itself and the excited light.

The function achieved by the different structures described above is that the light originating from the first light is allowed to exit to the output end and the light originating from the second light is prevented from exiting to the output end during the first time period, and the origin is allowed in the second time period. The light of the two rays exits to the output end and prevents light originating from the first light from exiting to the output end, and the second time period does not overlap with the first time period. In the first embodiment described above, the structure for realizing the above functions includes a control structure for controlling the switching of the two light sources to be synchronized with the wavelength converting means. In the above second and third embodiments, the structure for realizing the above-described functions includes a control structure for controlling the switching of one of the two light sources to be synchronized with the wavelength conversion device, and at the same time using a suitable one corresponding to the selected segment of the wavelength conversion device Spectroscopic filter. In the fourth embodiment described above, the structure for realizing the above functions includes a suitable spectroscopic filter corresponding to the selected segment of the wavelength conversion device. Other structures may also exist.

In some cases, the necessary conditions for the above two time periods not to overlap may be relaxed. For example, when the first light is blue light and the second light is red light, and when both the segment 41 and the segment 42 are transparent (as shown in the second figure), the blue and red light switches can be controlled to make the points When the segments 41 and/or 42 are in a period of time in the optical path of the incident light, the blue light and the red light are simultaneously turned on. This may cause purple light to exit during a period of time.

Embodiments of the present invention and Chinese patent applications in the background art The system described in CN101858496A differs in that the segment carrying the wavelength converting material in the latter solution is simultaneously excited by the two light sources, at which time the excited light originating from the two light sources (ultraviolet and blue light) is simultaneously emitted, thus requiring Both light sources can emit excitation light (such as blue light or UV light); in the solution of the invention, the light originating from the first light source and the light originating from the second light source are not designed to be simultaneously emitted, carrying the first wavelength conversion material. The segmentation (second segment) is only excited by the light of the first source, so that the second source is not required to emit excitation light, and the present invention has a wider range of choices on the source. Because the latter scheme requires that both light sources are excitation light sources, for example, a light source that does not carry a segment of the wavelength conversion material (corresponding to the second light source in the present invention), since the wavelength of the excitation light source is short, the light source is The selection range is small, mainly including a blue light source; and the second light source in the present invention is not limited to an excitation light source, that is, a light source longer than the wavelength of the excitation light source, according to the Stoke drift principle, compared with the latter scheme, In the invention, light emitted from a light source having a longer wavelength is used instead of the fluorescent powder to emit light, which has the advantage of high light conversion efficiency. In fact, the latter scheme uses blue light instead of fluorescent powder to emit light, which is only due to the fact that blue light is visible light. In addition, the reason why the use of blue light is more important is to use the UV light as an excitation light source to excite the green fluorescent powder, so the latter The use of blue light in the scheme is not for the purpose of improving the efficiency of light conversion, otherwise a light source longer than the blue light wavelength should be used.

In addition, in the latter solution, the wavelength conversion device is simultaneously excited by the two light sources, and thus originates from the two light sources for most of the entire time period. The excited light (ultraviolet and blue light) is simultaneously emitted; and the scheme of the present invention uses a monochromatic light source (such as a red light source) to directly replace the corresponding phosphor powder (such as red phosphor) to emit light. CN101858496A The energy of the excitation light is enhanced by the introduction of the second light source, thereby increasing the light energy output of the entire light source system; however, since the introduction of the second light source simultaneously increases the power consumption, the energy conversion efficiency of the entire system (refers to the conversion of unit energy into light energy) has not improved. In the present invention, although the second light source is also introduced, since the first light source and the second light source are mutually illuminable, the input of electric energy is not increased; and the low efficiency is replaced by the use of high efficiency monochromatic light. The phosphor powder illuminates the energy conversion efficiency of the system, and the invention also effectively increases the light energy output of the light source system, but does not increase the power consumption, so it is more energy efficient.

A Chinese patent application published in Japanese Patent Application No. CN 101592308 A, which is incorporated herein by reference, discloses a multi-color illuminating device based on wavelength conversion, which employs two light sources. The first source generates excitation light (such as blue or ultraviolet light) for exciting the wavelength converting material. The excitation light is directed to a turntable comprising a plurality of segments having wavelength converting material. The light emitted by the second light source (blue light or red light) is combined with the light excited by the wavelength converting material through a spectral filter, which is located downstream of the light-emitting path of the wavelength converting material. The switch of the second light source can be controlled, for example, the second light source will only be turned on when the turntable is turned to the boundary of the adjacent two segments. This system solves the spoke light problem caused by the turntable. Spoke light is involved in The ineffective mixing of light of different colors at the boundary of the two segments of the turntable is caused by the dispersion of the excited light and/or other factors.

The embodiment of the present invention differs from the system described in the above-mentioned Chinese patent application CN 101592308 in the position of the light combining means (light splitting filter) in the optical path. In an embodiment of the invention, the light combining means 3 is located upstream of the optical path of the wavelength converting material. In CN 101592308, the light combining means is located downstream of the optical path of the wavelength converting material.

One factor in the structure of CN 101592308 is that in the device, the function of the second light source is to correct the problem of spoke light generated by the rotating color wheel, so that the second light source is not suitable for placement upstream of the optical path of the rotating color wheel. In the device, the light of the second source is combined with the excited light of the wavelength converting material through the spectroscopic filter. The basis of the splitting filter combining the two lights is that the two light spectra do not overlap. Thus in the system of CN 101592308, the wavelength spectrum of the second source and the wavelength spectrum of the excited light must be largely separated so that they are combined by the spectroscopic filter. If the two spectra overlap, the overlap of one of them will be lost. This problem defines the choice of wavelength converting material and the color of the second source. For example, the spectrum of a typical yellow phosphor overlaps most of the typical red LED spectrum. Therefore, if the second light source is a red light LED, the yellow fluorescent powder is not suitable as a wavelength conversion material for rotating the color wheel. This is a critical limitation because yellow phosphors are widely used because of their high fluorescence conversion efficiency.

In an embodiment of the invention, since the first and second time periods are in time There is no overlap, originating from the first light (excitation light, blue light or ultraviolet light; excited light, green light or yellow light) and originating from the second light (direct light, red or green light or other color light) The spectrum of the light is not required to be non-overlapping, it may be non-overlapping, or it may be partially overlapped, and the spectroscopic filter 3 may combine the two kinds of light without causing unnecessary loss, thereby avoiding the above-mentioned patent CN 101592308. problem.

In an embodiment of the invention, since the second light is directly used to emit light rather than the excitation light, the second light does not need (although possible) to have the property of exciting the wavelength converting material. When the second light source 2 in the above embodiment is a red light source, the green light source is selectively used as the green direct outgoing light. In this alternative embodiment, the segment 41 of the wavelength conversion device carries a red wavelength converting material, and the segment 43 does not carry the wavelength converting material and is permeable to green light. Other adjustments to this system can be made accordingly.

Considering that the low light conversion efficiency of the prior art red phosphor is not conducive to the improvement of the color rendering index, when the first light generated by the first light source is blue light, and the second light generated by the second light source is red light, The light combining device combines the blue light and the red light, and projects the combined light beam obtained by the combined light onto the wavelength conversion material. The second segment of the wavelength conversion device can carry a wavelength converting material (such as green phosphor) that absorbs blue light and produces green light, and the wavelength converting device can also include a third segment that does not carry the wavelength converting material. The rotation control of the wavelength conversion device can be synchronized with the control of the output power of the first light source and the second light source by a control device. E.g, When the first segment of the wavelength conversion device is exposed in the optical path of the incident light (the combined light beam) (ie, in the first period of time), only the second light source (red light source) is turned on and the first light source (blue light source) is turned off, The red light output from the multi-color light-emitting device is completely provided by the red light source, thereby avoiding the problem of low light conversion efficiency caused by using the red phosphor. The blue light source is turned on only when the second segment and the third segment are exposed to the optical path of the incident light. In practical applications, the second light source may be other light sources than the red light source depending on the wavelength of the selected excitation light and the difference in the light conversion characteristics of the wavelength converting material.

The above is only the embodiment of the present invention, and is not intended to limit the scope of the invention, and the equivalent structure or equivalent process transformation of the present invention and the contents of the drawings may be directly or indirectly applied to other related technologies. The fields are all included in the scope of patent protection of the present invention.

1‧‧‧first light source

2‧‧‧second light source

3‧‧‧Lighting device

4‧‧‧wavelength conversion device

41-44, 41A-44A, 41B-44B, 41C-44C‧‧‧

5‧‧‧ sensor

6‧‧‧ Controller

7‧‧‧Output device

A, B‧‧‧ incident light

C‧‧‧Out of light

D‧‧‧ arrow

The first drawing is a schematic structural view of a first embodiment of the multicolor light emitting device of the present invention; the second drawing is a schematic structural view of a moving disk carrying a wavelength converting material in the multicolor light emitting device shown in the first figure; a schematic diagram of a structure of a control system in a multi-color light-emitting device shown in the first figure; a fourth diagram showing a time sequence of a moving disk, an inductive signal, and a light source in the multi-color light-emitting device shown in the first figure; 5A to 5C are the second and the second of the multicolor light-emitting device of the present invention 3. Schematic diagram of the structure of the wavelength conversion device in the fourth embodiment.

1‧‧‧first light source

2‧‧‧second light source

3‧‧‧Lighting device

4‧‧‧wavelength conversion device

7‧‧‧Output device

A, B‧‧‧ incident light

C‧‧‧Out of light

D‧‧‧ arrow

Claims (14)

a multi-color light emitting device comprising: a first light source for emitting a first light; a second light source for emitting a second light, wherein the second light source is visible light and used for filling light; and the wavelength conversion device comprises at least two Segmenting, carrying no first segment of wavelength converting material and second segment carrying first wavelength converting material, the first wavelength converting material absorbing the first light and generating a third light; optical means for guiding Transmitting the first and second rays as incident light to the wavelength conversion device, the wavelength conversion device being movable relative to the first and second light sources such that the first and second segments are sequentially exposed And an output end for receiving the emitted light emitted by the wavelength conversion device; wherein, in the first period of time, allowing light originating from the first light source to be output to the output end, and blocking Light originating from the second light source is output to the output end; in a second period of time, light originating from the second light source is allowed to be output to the output end, and light originating from the first light source is prevented from being output to the a first time period is a time period when the second segment of the wavelength conversion device is exposed in the optical path of the incident light, and the second time period is when the first segment of the wavelength conversion device is exposed The time period in which the optical path of the incident light is described. The multi-color light-emitting device of claim 1, wherein the second light is red light and overlaps the spectral portion of the third light. The multi-color light-emitting device of claim 1, wherein the wavelength conversion device further comprises: a third segment carrying the second wavelength conversion material absorbing the first light and generating the fourth light or not carrying the wavelength Converting material; and when the third segment is exposed in the optical path of the incident light, allowing light originating from the first source to be output to the output, preventing light originating from the second source from being output to the output; fourth segment Carrying a third wavelength converting material, and the third wavelength converting material absorbs the first light and generates yellow light; wherein the first light emitted by the first light source is blue light or ultraviolet light, and the second light emitted by the second light source is red light The third light generated by the first wavelength converting material is green light, and the fourth light generated by the second wavelength converting material is blue light. The multi-color light-emitting device of claim 1, further comprising: an inductor coupled to the wavelength conversion device for sensing a relative movement position of the wavelength conversion device and emitting an induction signal indicative of the sensing position; and controlling And the sensor is connected to generate a control signal for turning on and off the first light source or the second light source or the two light sources according to the sensing signal; wherein the sensing signal indicates the beginning of the first time period or the second time period And the controller generates the control signal to turn on the first light source and turn off the second light source at the beginning of the first time period, and turn on the second light source and turn off the first light source at the beginning of the second time period. The multi-color light-emitting device of claim 1, further comprising: a first spectral filter fixedly disposed on the second segment of the wavelength conversion device; when the first spectral filter is placed on the optical path of the incident light, the first spectral filter blocks the second light from being emitted The exit end. The multi-color light-emitting device of claim 5, further comprising: an inductor coupled to the wavelength conversion device for sensing a relative movement position of the wavelength conversion device and emitting an induction signal indicative of the beginning of the second time period And a controller coupled to the inductor for generating a control signal for turning off the first light source during a second time period and opening the first light source for a first time period according to the sensing signal. The multi-color light-emitting device of claim 5, further comprising a second spectral filter fixedly disposed on the first segment of the wavelength conversion device, wherein the second spectral filter is placed at the incident When the light is on the light path, the second beam splitting filter blocks the first light from exiting to the exit end. The multi-color light emitting device comprises: a first light source for generating a first light, the first light is blue light or ultraviolet light; a second light source for generating a second light, the second light is red light, and the second The light source is visible light and is used for filling light; the wavelength conversion device comprises at least two segments, a first segment not carrying the wavelength conversion material and a second segment carrying the first wavelength conversion material, and the first wavelength conversion material is absorbed a first light and generating a third light; and optical means for directing the first and second light rays as incident light to the wavelength conversion device; Wherein the wavelength conversion device is movable relative to the first and second light sources such that the first and second segments are sequentially exposed in the optical path of the incident light; wherein the first light source is turned on at least for the first time period, a period of time is a period of time when the second segment of the wavelength conversion device is exposed in the optical path of the incident light; and the second source is turned on at least for the second period of time, and the second period is the first of the wavelength conversion devices A period of time when a segment is exposed to the optical path of the incident light. The multicolor light-emitting device of claim 8, wherein the third light beam overlaps the spectral portion of the red light. The multi-color light-emitting device of claim 8, wherein the wavelength conversion device further comprises: a third segment carrying a second wavelength conversion material that absorbs the first light and generates the fourth light or does not carry a wavelength converting material; and the first light source is turned on when the third segment is exposed in the optical path of the incident light; wherein the first light is blue light, the third light generated by the first wavelength converting material is green light, and the third light The segment does not carry the wavelength converting material, and the first light source is turned on only when the first time period and the third segment are exposed in the optical path of the incident light, and the second light source is turned on only for the second time period. a multi-color light-emitting device comprising: a first light source for generating a first light; a second light source for generating a second light, wherein the second light source is visible light and used for filling light; and the wavelength conversion device comprises at least two Segmenting, the first segment carrying the wavelength converting material and the second segment carrying the first wavelength converting material, the first wavelength converting material absorbing the first light and generating a third light; An optical device for directing the first and second rays as incident light to the wavelength conversion device; wherein the wavelength conversion device is movable relative to the first and second light sources to cause the first and second segments Exposing sequentially in the optical path of the incident light; wherein the first light source is turned on in the first time period and is turned off in the second time period, the second light source is turned on in the second time period and is turned off in the first time period, the first time period A period of time when the second segment of the wavelength conversion device is exposed in the optical path of the incident light, and the second period of time is a period of time when the first segment of the wavelength conversion device is exposed in the optical path of the incident light. The multi-color light-emitting device of claim 11, wherein the wavelength conversion device further comprises: a third segment, the third segment carrying a second wavelength conversion material that absorbs the first light and generates the fourth light Or not carrying the wavelength conversion material; and the first light source is turned on when the third segment is exposed in the optical path of the incident light; wherein the first light emitted by the first light source is blue light or ultraviolet light, and the second light source emits The second light is red light, the third light generated by the first wavelength converting material is green light, and the fourth light generated by the second wavelength converting material is blue light. The multi-color light-emitting device of claim 12, wherein the wavelength conversion device further comprises a fourth segment carrying a third wavelength converting material, the third wavelength converting material absorbing the first light and generating yellow light. The multi-color light-emitting device of claim 11, further comprising: an inductor coupled to the wavelength conversion device for sensing a relative movement position of the wavelength conversion device and emitting an induced signal indicative of the sensing position; And a controller, configured to generate, according to the sensing signal, a control signal for turning on and off the first light source or the second light source or the two light sources.