The present disclosure relates to the field of illumination and projection technologies, and in particular, to a wavelength conversion device, and a light-emitting device and a projection device that use the wavelength conversion device.
Currently, light sources of a projection device mainly include a pure laser light source and a laser fluorescence mixed light source. The pure laser light source typically adopts a red laser, a green laser, and a blue laser to emit laser light for illumination, resulting in a high cost. In addition, due to immaturity of technologies of the red laser light and the green laser light, there is a problem of low electro-optical conversion efficiency. The laser light-fluorescence mixed light source typically adopts the blue laser light as the primary laser light to excite different phosphors to generate fluorescence of different colors, which greatly reduces costs compared with the pure laser light source.
In a method for generating fluorescence in the prior art, different phosphors are coated on a color wheel, and a motor drives the color wheel to generate sequential fluorescence. However, an optical spectrum of the generated fluorescence is relatively broad, and a shading film is required for filtering. Filtering of the fluorescence is usually implemented by adding a corresponding shading film at an inner side or an outer side of the color wheel. However, the red light efficiency is low, and the brightness of a light source cannot be maximized.
To increase a proportion of the red light efficiency in a white balance color gamut to achieve a broader color gamut and a higher light efficiency, a common solution is to add a red laser light source and use another color wheel for light scattering and exiting, so that red laser light generated by the red laser light source and the red fluorescence are mixed to enter an optical machine. However, this increases space occupied by an overall structure of the light source, and is contrary to an actual requirement for reducing occupied space.
An objective of the present disclosure is to provide a wavelength conversion device that can increase brightness of a light source and reduce its occupied space, and a light-emitting device and a projection device that use the wavelength conversion device.
To achieve the foregoing objective, the present disclosure provides a wavelength conversion device, and the wavelength conversion device includes a substrate capable of rotating around a rotation axis. The substrate includes a first surface and a second surface that face away from each other, and a side surface connecting the first surface and the second surface. The side surface is not perpendicular to the first surface. A wavelength conversion material layer is provided on the first surface, and the side surface includes a first region and a second region that are configured to reflect an incident light beam.
In an implementation, a first light diffuser is provided in the first region, a second light diffuser is provided in the second region, and the first light diffuser and the second light diffuser are parallel to each other and configured to diffuse and reflect the incident light beam.
In an implementation, the first light diffuser includes a first transmission-type diffusion film and a first reflective film, and the first transmission-type diffusion film is located on a side of the first region facing away from the rotation axis; and the second light diffuser includes a second transmission-type diffusion film and a second reflective film, and the second transmission-type diffusion film is located on a side of the second region facing away from the rotation axis.
In an implementation, a projection of the first region on a plane perpendicular to the rotation axis and a projection of the wavelength conversion material layer on the plane perpendicular to the rotation axis are connected end to end to form a circular ring; and a projection of the second region on the plane perpendicular to the rotation axis and the projection of the wavelength conversion material layer on the plane perpendicular to the rotation axis overlap.
In an implementation, the first region and the second region are parallel to each other, both of a projection of the first region on a plane perpendicular to the rotation axis and a projection of the second region on the plane perpendicular to the rotation axis are of an annular sector shape, and the annular sector shape of the projection of the first region and the annular sector shape of the projection of the second region have a same circle center and are arranged symmetrically with respect to the circle center.
In an implementation, an angle between the first region and the rotation axis is greater than 40° and smaller than 90°.
In an implementation, the side surface is provided with a groove recessed toward the rotation axis, and the first region and the second region are both formed between the second surface and the groove.
In an implementation, the wavelength conversion device further includes a reflective layer located between the first surface and the wavelength conversion material layer.
In an implementation, the wavelength conversion material layer includes a first wavelength conversion section, a second wavelength conversion section and a third wavelength conversion section that are sequentially and adjacently arranged and are provided with different wavelength conversion materials, respectively.
In an implementation, a projection of the first region on a plane perpendicular to the rotation axis and a projection of the second wavelength conversion section on the plane perpendicular to the rotation axis are diagonally arranged with the rotation axis as a center; and a projection of the second region on the plane perpendicular to the rotation axis and the projection of the second wavelength conversion section on the plane perpendicular to the rotation axis completely overlap.
The present disclosure further provides a light-emitting device, and the light-emitting device includes a first light source, a second light source and the foregoing wavelength conversion device. The first light source is configured to emit first laser light, the first laser light is incident to the first region and the wavelength conversion material layer in time sequence, and the first laser light incident to the wavelength conversion material layer is capable of being converted into fluorescence. The second light source is configured to emit second laser light, and the second laser light is mixed with fluorescence of a same color after being reflected by the second region and is emitted.
In an implementation, the first light source is located on a side of the first surface, the second light source is formed on a side of the second surface, the first laser light emitted by the first light source is blue laser light, and the second laser light emitted by the second light source is one of red laser light, green laser light, blue laser light and yellow laser light.
In an implementation, the light-emitting device further includes a light guiding assembly, and the light guiding assembly includes a dichroic sheet, a mirror, a focusing lens and a regional film, and is configured to guide light of various colors emitted by the wavelength conversion device to be emitted along a same path.
The present disclosure further provides a projection device, including the foregoing light-emitting device.
According to the wavelength conversion device and the light-emitting device provided in the present disclosure, the first laser light emitted by the first light source and the second laser light emitted by the second light source are reflected and scattered by the first region and the second region of the side surface of the substrate, respectively. This not only can overcome an existing disadvantage that the brightness of a light source cannot be maximized, but also can make the structure more compact to facilitate reducing of the occupied space.
Light-emitting device 100
First light source 10
Second light source 20
Wavelength conversion device 30
Substrate 31
First surface 311
Second surface 312
Side surface 313
First region 3131
Second region 3132
Groove 3133
Driving member 32
Rotation axis 33
Reflective layer 34
Wavelength conversion material layer 35
First wavelength conversion section 351
Second wavelength conversion section 352
Third wavelength conversion section 353
First light diffuser 36
First transmission-type diffusion film 361
First reflective film 362
Second light diffuser 37
Second transmission-type diffusion film 371
Second reflective film 372
Light guiding assembly 40
Dichroic sheet 41
Focusing lens 42
Regional film 43
First reflector 44
Second reflector 45
Collimating lens assembly 50
The present disclosure is further described in the following specific implementation with reference to the accompanying drawings.
Referring to
Specifically, the first light source 10 is configured to emit first laser light. The first laser light can be used as exciting light to excite a wavelength conversion material to generate fluorescence. The second light source 20 is configured to emit second laser light. In this embodiment, the first laser light emitted by the first light source 10 is blue laser light, and the second laser light emitted by the second light source 20 is red laser light. In other embodiments, the second laser light emitted by the second light source 20 can be green laser light, blue laser light or yellow laser light.
Also referring to
Specifically, the substrate 31 includes a first surface 311, a second surface 312 and a side surface 313. The first surface 311 and the second surface 312 are respectively located on two opposite sides of the substrate 31. The side surface 313 is enclosed between the first surface 311 and the second surface 312, and the side surface 313 is not parallel to the first surface 311. In this embodiment, the first surface 311 and the second surface 312 are parallel to and spaced apart from each other, and are each perpendicular to the rotation axis 33.
Further, a reflective layer 34 and a wavelength conversion material layer 35 that are sequentially laminated are provided on the first surface 311 of the substrate 31, that is, the reflective layer 34 is located between the wavelength conversion material layer 35 and the first surface 311. A wavelength conversion material is provided in the wavelength conversion material layer 35, so that a wavelength conversion is performed on the first laser light incident to the wavelength conversion material layer 35 to generate fluorescence. In addition, a color of the fluorescence is affected by a type of the wavelength conversion material of the wavelength conversion material layer 35.
Referring to
It should be noted that, the reflective layer 34 can reflect the first laser light incident to the wavelength conversion material layer 35, to improve conversion efficiency of the first laser light and reduce light loss.
Referring to
A projection of the first region 3131 a plane perpendicular to the rotation axis 33 and a projection of the wavelength conversion material layer 35 on the plane perpendicular to the rotation axis 33 are adjacently connected to each other end to end to form a circular ring, and a center of the circular ring is located on the rotation axis 33. A projection of the second region 3132 on the plane perpendicular to the rotation axis 33 and a projection of the wavelength conversion material layer 35 on the plane perpendicular to the rotation axis 33 overlap. It should be noted that, “overlap” can be a complete overlap, or can be a partial overlap.
In this embodiment, the first region 3131 and the second region 3132 are parallel to each other, and a projection of the first region 3131 on the plane perpendicular to the rotation axis 33 and a projection of the second region 3132 on the plane perpendicular to the rotation axis 33 are each of an annular sector shape. Specifically, the annular sector shape of the projection of the first region 3131 and the annular sector shape of the projection of the second region 3132 have a same circle center, and are arranged symmetrically with respect to the circle center. In other embodiments, projections of the first region 3131 and the second region 3132 on the plane perpendicular to the rotation axis 33 are not limited to being arranged symmetrically with respect to the center. Preferably, an angle between the first region 3131 and the rotation axis 33 is between greater than 40° and smaller than 90°, which facilitates an arrangement of an optical path.
In this embodiment, the projection of the first region 3131 on the plane perpendicular to the rotation axis 33 and the projection of the second wavelength conversion section 352 on the plane perpendicular to the rotation axis 33 are diagonally arranged with the rotation axis as a center, and the projection of the second region 3132 on the plane perpendicular to the rotation axis 33 and the projection of the second wavelength conversion section 352 on the plane perpendicular to the rotation axis 33 completely overlap.
Referring to
Referring to
The substrate 31 is driven by the driving member 32 to rotate around the rotation axis 33, and the blue laser light emitted by the first light source 10 is incident to the wavelength conversion material layer 35 and the first light diffuser 36 in time sequence. When the blue laser light emitted by the first light source 10 is incident to the first light diffuser 36 (referring to
When the blue laser light emitted by the first light source 10 is incident to the wavelength conversion material layer 35 (referring to
In this embodiment, the first light source 10 is located at a side of the first surface 311 of the substrate 31, and the second light source 20 is located at a side of the second surface 312 of the substrate 31. In other embodiments, the first light source 10 is not limited to be arranged at the side of the first surface 311 of the substrate 31, and the second light source 20 is not limited to be arranged at the side of the second surface 312 of the substrate 31. Another optical elements such as a reflective surface can be used to cause the first laser light emitted by the first light source 10 to be incident to the wavelength conversion material layer 35 and the first light diffuser 36 in time sequence, and to cause the first laser light emitted by the second light source 20 to be incident to the second light diffuser 37. It can be understood that, arranging the first light source 10 at the side of the first surface 311 of the substrate 31 and arranging the second light source 20 at the side of the second surface of the substrate 31 can reduce an optical distance, which makes the structure more compact.
Further, the light-emitting device 100 further includes a light guiding assembly 40. The light guiding assembly 40 includes a dichroic sheet 41, a plurality of focusing lenses 42, a regional film 43, a first mirror 44 and a second mirror 45, so that light of various colors emitted by the wavelength conversion device 30 passes through the light guiding assembly 40 and then enters other subsequent optical devices (such as, a spatial light modulator 200) along a same path.
Specifically, the dichroic sheet 41 can reflect the blue light and transmit light of other colors. The blue laser light emitted by the first light source 10 is incident to the wavelength conversion material layer 35 or the first light diffuser 36 after being reflected by the dichroic sheet 41. Fluorescence emitted by the wavelength conversion material layer 35 passes through the dichroic sheet 41 and is transmitted by the regional film 43 after being reflected by the first mirror 44. Light beams emitted from the first light diffuser 36 and the second light diffuser 37 are reflected by the regional film 43 after being reflected by the second mirror 45. Therefore, the light of various colors emitted by the wavelength conversion device 30 is emitted along a same path after passing through the regional film 43.
The plurality of focusing lenses 42 are arranged on an optical path between the dichroic sheet 41 and the substrate 31, an optical path between the dichroic sheet 41 and the first mirror 44, an optical path between the substrate 31 and the second mirror 45, and an optical path between the second mirror 45 and the regional film 43, respectively, to achieve a light-focusing effect.
Further, the light-emitting device 100 further includes a collimating lens assembly 50. The light emitted from the regional film 43 can be collimated after passing through the collimating lens assembly 50.
It should be noted that, a lot of heat is generated in the process in which the first laser light emitted by the first light source 10 is incident to the wavelength conversion material layer 35 and converted into fluorescence, and the arrangement of the groove 3133 facilitates the heat dissipation of the wavelength conversion device 30. In addition, the groove 3133 is of a ring shape, so that the substrate 31 forms a double-layer structure. Practice has shown that double-layer dynamic balance adjustment of the substrate 31 has a better vibration effect compared to a vibration effect achieved by a single-layer dynamic balance adjustment.
The light-emitting device 100 provided in any one of the foregoing embodiments can be applied to projection and display systems, such as a liquid crystal display (LCD) or a digital light processor (DLP) projector; or can be applied to an illumination system, such as automotive illuminating lights or stage lights; or can be applied to the field of 3D display technologies.
Further, the present disclosure further provides a projection device (not shown). The projection device includes the light-emitting device 100 according to any one of the foregoing embodiments.
The foregoing descriptions are merely implementations of the present disclosure, and are not intended to limit the patent scope of the present disclosure. Any equivalent structural modification or any equivalent procedure modification made with reference to the content of the specification and the accompanying drawings of the present disclosure, or directly or indirect application to other related technical fields shall fall within the patent protection scope of the present disclosure.
Number | Date | Country | Kind |
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201811645685.X | Dec 2018 | CN | national |
Filing Document | Filing Date | Country | Kind |
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PCT/CN2019/127278 | 12/23/2019 | WO | 00 |