Projection system capable of switching light-emitting modes

Abstract

The utility model discloses a projection system capable of switching light-emitting modes. The projection system comprises a laser light source, a first collimator, a color wheel, a second collimator, a free-form surface reflector, a DMD device, a projection lens and a driving mechanism for driving the color wheel to move and rotate around the center, which are sequentially arranged along the direction of a light path. The color wheel comprises a yellow fluorescent area, a color fluorescent area and a heat dissipation area which are distributed in different radial areas, and the driving mechanism enables the yellow fluorescent area or the color fluorescent area to be located in the light path direction of the light source by moving the color wheel. By switching the working areas of the color wheel, the same light source can realize high-brightness white light illumination and color projection, so that the vehicle-mounted headlamp color projection system can be applied to the vehicle-mounted headlamp color projection technology.

Description

Technical Field

[0001] The utility model relates to the technical field of vehicle lamps, in particular to a projection system with a switchable light-emitting mode. Background Art

[0002] A projection headlamp is a kind of lamp that uses DLP (Digital Light Processing) technology to project pixel points onto the road surface through a DMD (Digital Micro-mirror Device) device. A single lamp can achieve high-precision ADB (Adaptive Driving Beam) lighting of 900,000 to 1.3 million pixels, or use its pixelated projection function to achieve functions such as video playback and symbol display. In existing vehicle-mounted projection headlamps, the solutions for achieving high-brightness white light illumination include using multiple white LEDs as light sources, or using blue laser to excite yellow fluorescence and then synthesizing white light; since there is no automotive-grade color LED light source, in order to achieve color projection, generally the method of using blue laser to excite a color wheel to generate red and green light is used, and then after beam combination, it is used to illuminate the DMD. This solution is mostly used in the field of home projectors.

[0003] In order to simultaneously achieve white light illumination and color projection, the existing solution is to synthesize white light through excited RGB light, and its efficiency is lower than that of separately exciting yellow fluorescence. In order to meet the strict requirements for volume, power consumption, and heat dissipation in vehicle headlamp applications, it is inevitable to sacrifice brightness.

[0004] Therefore, how to implement a projection system that integrates high-brightness white light projection illumination and color projection functions is a technical problem that needs to be solved currently. Summary of the Utility Model

[0005] In order to solve the technical problem that the projection system of the existing technology cannot achieve both high-brightness white light illumination and color projection through the same light source, the utility model provides a projection system with a switchable light-emitting mode to solve the above problems.

[0006] The technical solution adopted by the utility model to solve its technical problems is: a projection system with a switchable light-emitting mode, including a laser light source, a first collimator, a color wheel, a second collimator, a free-form surface reflector, a DMD device, a projection lens, and a driving mechanism that drives the color wheel to move and rotate around the center, which are arranged in sequence along the optical path direction.

[0007] The color wheel includes a yellow fluorescence area, a color fluorescence area, and a heat dissipation area distributed in different radial regions. The driving mechanism moves the color wheel to make the yellow fluorescence area or the color fluorescence area located in the optical path direction of the light source.

[0008] Further, the driving mechanism includes a rotating motor connected to the center of the color wheel.

[0009] Further, the heat dissipation area is the inner ring of the color wheel, and the yellow fluorescent area and the color fluorescent area are located on the periphery of the heat dissipation area.

[0010] Further, a plurality of fan blades are arranged in a circumferential array in the heat dissipation area.

[0011] Further, the driving mechanism further includes an offset motor and a transmission component connected to the offset motor. The transmission component is connected to the rotating motor, and the transmission component converts the output motion of the offset motor into a translational motion of the rotating motor.

[0012] Further, the transmission component includes two fixed mounting plates, a screw rod and a guide rod located between the two mounting plates. The screw rod is rotationally matched with the mounting plate. The offset motor is connected to the screw rod, and the rotating motor passes through the guide rod and is threadedly connected to the screw rod.

[0013] Further, the transmission component includes a connecting rod, a cam, two fixed mounting plates and a guide rod located between the two mounting plates. The rotating motor passes through the guide rod. The offset motor drives the cam to rotate. One end of the connecting rod abuts against the outer edge of the cam, and the other end passes through the mounting plate and is connected to the rotating motor. An elastic resetting member is arranged between one side of the rotating motor and the mounting plate. The elastic resetting member and the connecting rod are located on both sides of the rotating motor.

[0014] Further, the laser light source is a blue laser.

[0015] Further, the color wheel is a transmissive color wheel. The emitting direction of the laser light source is perpendicular to the plane of the color wheel. The first collimator and the second collimator are located on both sides of the color wheel.

[0016] Further, the color wheel is a reflective color wheel. The emitting direction of the laser light source is parallel to the plane of the color wheel. The first collimator and the second collimator are located at the same position. The projection system further includes a dichroic mirror that reflects the light beam from the laser light source to the first collimator and reflects the light beam from the second collimator to the free-form surface mirror.

[0017] The beneficial effects of the present utility model are as follows:

[0018] (1) By switching the working area of the color wheel, the same light source of the present utility model can both achieve high-brightness white light illumination and color projection, so that it can be applied to the color projection technology of vehicle headlamps.

[0019] (2) A heat dissipation area is provided in the color wheel of the present utility model to continuously dissipate heat from the fluorescent area, thereby improving the stability of the laser light source during operation. Description of the Drawings

[0020] The present utility model will be further described below in conjunction with the accompanying drawings and embodiments.

[0021] Figure 1 is the front view of a specific embodiment of the projection system with a switchable light-emitting mode according to the present utility model;

[0022] Figure 2 is Figure 1 a schematic diagram of the projection system with a switchable light-emitting mode shown in the color projection state;

[0023] Figure 3 is Figure 1 a schematic diagram of the projection system with a switchable light-emitting mode shown in the white projection state;

[0024] Figure 4 is a schematic diagram of the color wheel in the present utility model;

[0025] Figure 5 is the front view of a specific embodiment of the projection system with a switchable light-emitting mode according to the present utility model;

[0026] Figure 6 is a schematic diagram of a specific embodiment of the color wheel drive structure in the present utility model.

[0027] In the figure, 1 is a laser light source, 2 is a first collimator, 3 is a color wheel, 301 is a yellow fluorescent region, 302 is a color fluorescent region, 303 is a heat dissipation region, 4 is a second collimator, 5 is a free-form surface mirror, 6 is a DMD device, 7 is a projection lens, 8 is a drive mechanism, 801 is a rotation motor, 802 is an offset motor, 803 is a mounting plate, 804 is a screw, 805 is a guide rod, 806 is a connecting rod, 807 is a cam, 808 is an elastic reset member, 9 is a fan blade, and 10 is a dichroic mirror. Specific Embodiment

[0028] The embodiments of the present utility model will be described in detail below. The examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements with the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary and are only used to explain the present utility model and should not be construed as a limitation to the present utility model.

[0029] A projection system with switchable light-emitting modes, comprising a laser light source 1, a first collimator 2, a color wheel 3, a second collimator 4, a free-form surface mirror 5, a DMD device 6, a projection lens 7, and a drive mechanism 8 arranged in sequence along the optical path direction. The first collimator 2 and the second collimator 4 collimate the divergent light beams to the fluorescent layer of the color wheel 3 and the free-form surface mirror 5 respectively. The collimator can be one or more condenser lenses.

[0030] The color wheel 3 includes a yellow fluorescent region 301, a color fluorescent region 302, and a heat dissipation region 303 distributed in different radial regions. Preferably, all three regions are annular regions. The heat dissipation region 303 is an opaque region for dissipating heat from the yellow fluorescent region 301 and the color fluorescent region 302. The drive mechanism 8 has two drive functions. The first is to drive the color wheel 3 to move so that the yellow fluorescent region 301 or the color fluorescent region 302 is located in the optical path direction of the light source. The second is to drive the color wheel 3 to rotate around the center. Since the yellow fluorescent region 301, the color fluorescent region 302, and the heat dissipation region 303 are located in different radial regions, when the fluorescent region located in the optical path of the light source is determined, the rotation of the color wheel 3 around the center will not cause the change of the fluorescent region in the optical path. The rotation of the color wheel 3 can realize the color projection of the color fluorescent region 302.

[0031] In order to be able to realize white light projection, the laser light source 1 can be selected as a blue laser. When the yellow fluorescent region 301 of the color wheel 3 is located on the optical path, the laser excites the yellow fluorescent layer, and the excited yellow light is combined with the inherent blue light to form white light. When the color fluorescent region 302 of the color wheel 3 is located on the optical path, the laser excites the color fluorescent layer, and at this time, colored light will be generated.

[0032] The drive mechanism 8 controls the rotation of the color wheel 3, which can be achieved but not limited to by a rotation motor 801 connected to the center of the color wheel 3.

[0033] The yellow fluorescent region 301, the color fluorescent region 302, and the heat dissipation region 303 can be arranged arbitrarily in the radial direction of the color wheel 3. If the heat dissipation region 303 is located between the yellow fluorescent region 301 and the color fluorescent region 302, during the translation of the color wheel 3 when switching different light-emitting modes, it needs to pass through the heat dissipation region 303, and rapid switching of the light-emitting mode cannot be achieved. Therefore, it is preferred to arrange the yellow fluorescent region 301 and the color fluorescent region 302 adjacent to each other, that is, the heat dissipation region 303 is located in the outermost or innermost circle, and preferably the heat dissipation region 303 is located in the innermost circle.

[0034] The heat dissipation region 303 is an opaque region with fins. The airflow generated during rotation can assist in dissipating heat from the yellow fluorescent region 301 and the color fluorescent region 302, improving the system stability. As a preference, as Figure 3 shown, a number of fan blades 9 are arranged in a circumferential array in the heat dissipation region 303.

[0035] The rotation and translation of the color wheel 3 can be achieved through two independent structures, which requires arranging two connection points on the color wheel 3. When the color wheel 3 rotates, it will drive the translation drive structure to move, which is likely to cause damage to the drive structure. Therefore, preferably, the drive mechanism 8 further includes an offset motor 802 and a transmission component connected to the offset motor 802. The transmission component is connected to the rotation motor 801, and the transmission component converts the output motion of the offset motor 802 into the translation motion of the rotation motor 801. At this time, there is only one connection point between the drive mechanism 8 and the color wheel 3, and the connection position is at the center of the color wheel 3. When the offset motor 802 is started, it can drive the rotation motor 801 and the color wheel 3 to translate simultaneously. When the rotation motor 801 is started, the offset motor 802 will not be affected.

[0036] Embodiment 1

[0037] As Figures 1-3 shown, a projection system with a switchable light-emitting mode includes a laser light source 1, a first collimator 2, a color wheel 3, a second collimator 4, a free-form surface mirror 5, a DMD device 6, a projection lens 7, and a drive mechanism 8 that drives the color wheel 3 to move and rotate around the center, which are arranged in sequence along the optical path direction.

[0038] The color wheel 3 includes a yellow fluorescent region 301, a color fluorescent region 302, and a heat dissipation region 303 distributed in different radial regions. As Figure 4 shown, in this embodiment, the heat dissipation region 303 is located in the innermost circle of the color wheel 3, and the color fluorescent region 302 is located in the outermost circle of the color wheel 3. The color fluorescent region 302 includes at least three partitions for realizing color projection. In this example, they are fluorescent layers of three colors, R, G, and B. The ratios corresponding to the R, G, and B fluorescent layers are 0.32:0.49:0.19. Through appropriate matching, the brightness of color projection can be effectively improved.

[0039] The drive mechanism 8 in this embodiment realizes the offset of the color wheel 3 through the following transmission component:

[0040] As Figure 1 shown, the transmission component includes two fixed mounting plates 803 and a screw 804 and a guide rod 805 located between the two mounting plates 803. The screw 804 is rotationally matched with the mounting plate 803. The offset motor 802 is connected to the screw 804. The rotation motor 801 passes through the guide rod 805 and is threadedly connected to the screw 804. The mounting plate 803 and the offset motor 802 are respectively fixedly arranged. When the offset motor 802 is started, it drives the screw 804 to rotate. Due to the limitation of the guide rod 805, the housing of the rotation motor 801 cannot rotate. Since the rotation motor 801 is threadedly engaged with the screw 804, when the screw 804 rotates, the rotation motor 801 will generate a translation motion, thereby driving the connected color wheel 3 to translate. As Figure 2In the system state shown, the collimated laser irradiates the color fluorescence area 302 of the color wheel 3. At this time, three primary colors of light, R, G, and B, will be generated according to the rotation angle of the color wheel 3. When the offset motor 802 drives the rotation motor 801 and the color wheel 3 to move leftward, the collimated laser irradiates on the yellow fluorescence area 301 of the color wheel 3 (as Figure 3 shown), and the laser excites yellow light to synthesize white light with the inherent blue light.

[0041] In this embodiment, the color wheel 3 is a transmissive color wheel. The emission direction of the laser light source 1 is perpendicular to the plane of the color wheel 3, and the first collimator 2 and the second collimator 4 are located on both sides of the color wheel 3.

[0042] During operation, the blue laser light source 1 emits blue laser light, which is collimated by the first collimator 2 onto the fluorescent layer of the color wheel 3. After transmissive excitation, the divergence angle of the light beam excited by fluorescence is very large. Therefore, it needs to be collimated again by the second collimator 4. The collimated light beam is modulated and reflected by the free-form surface mirror 5 and converges onto the micromirror array of the DMD device 6 in a certain size. Among them, the micromirrors in the "On" state reflect the light beam into the projection lens 7, and an image is formed through projection. Both the first collimator 2 and the second collimator 4 are composed of two condenser lenses.

[0043] Embodiment 2

[0044] The difference between this embodiment and the above embodiment is that the color wheel 3 is changed from a transmissive color wheel 3 to a reflective color wheel 3. At this time, the structure of the driving mechanism 8 can remain unchanged, but only the positions of other components guiding the light beam change. Specifically, it means that the emission direction of the laser light source 1 is parallel to the plane of the color wheel 3, and the first collimator 2 and the second collimator 4 are located at the same position, that is, the first collimator 2 and the second collimator 4 are the same component. Here, the first collimator 2 refers to the name when the collimator performs the first reflection, and the second collimator 4 refers to the name when the collimator performs the second reflection. Moreover, the projection system further includes a dichroic mirror 10 that reflects the light beam from the laser light source 1 to the first collimator 2 and reflects the light beam from the second collimator 4 to the free-form surface mirror 5.

[0045] As Figure 5 shown, the blue light emitted by the blue laser light source 1 is reflected at the dichroic mirror 10, converges onto the color wheel 3 through the first collimator 2. The fluorescence emission direction excited by it is opposite to the incident laser direction, is collimated by the second collimator 4, and then enters the free-form surface mirror 5 through the dichroic mirror 10. After modulation and reflection, finally, an illumination spot of a certain size is formed to illuminate the DMD device 6. Among them, the micromirrors in the "On" state reflect the light beam into the projection lens 7, and an image is formed through projection.

[0046] Embodiment 3

[0047] The structure of the transmission component in this embodiment is different from that in the above embodiment. AsFigure 6 As shown in the figure, the transmission assembly of this embodiment includes a connecting rod 806, a cam 807, two fixedly arranged mounting plates 803, and a guide rod 805 located between the two mounting plates 803. A rotating motor 801 passes through the guide rod 805. An offset motor 802 drives the cam 807 to rotate. One end of the connecting rod 806 abuts against the outer edge of the cam 807, and the other end passes through the mounting plate 803 and is connected to the rotating motor 801. An elastic reset member 808 is arranged between one side of the rotating motor 801 and the mounting plate 803. The elastic reset member 808 and the connecting rod 806 are located on both sides of the rotating motor 801.

[0048] As Figure 6 shown in the figure, the mounting plate 803 and the offset motor 802 are fixedly arranged respectively. The central axis of the offset motor 802 is perpendicular to the central axes of the connecting rod 806 and the guide rod 805. The offset motor 802 is approximately connected to the center of the cam 807 to drive the cam 807 to rotate, so that different parts of the outer edge of the cam 807 abut against the connecting rod 806. The function of the guide rod 805 is to provide guidance for the translation of the rotating motor 801 to prevent the rotating motor 801 from shaking. When the long-edge outer edge of the cam 807 abuts against the connecting rod 806, the cam 807 pushes the connecting rod 806 to move to the right, so that the rotating motor 801 and the color wheel 3 move to the right. At the same time, the elastic reset member 808 contracts and deforms. When the short-edge outer edge of the cam 807 faces the connecting rod 806, the rotating motor 801 moves to the left under the action of the elastic reset member 808, so that the connecting rod 806 continuously abuts against the outer edge of the cam 807.

[0049] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "left", "right", "inner", "outer", "axial", "radial", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0050] In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0051] In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments.

[0052] Taking the above-mentioned ideal embodiments of the present utility model as inspiration, through the above description, relevant staff can completely make various changes and modifications without departing from the technical idea of this utility model. The technical scope of this utility model is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A projection system with switchable light-emitting modes, characterized in that: It includes a laser light source, a first collimator, a color wheel, a second collimator, a free-form surface mirror, a DMD device, a projection lens, and a driving mechanism that drives the color wheel to move and rotate around the center, which are arranged in sequence along the optical path direction; The color wheel includes a yellow fluorescent region, a color fluorescent region, and a heat dissipation region distributed in different radial regions. The driving mechanism moves the color wheel to make the yellow fluorescent region or the color fluorescent region located in the optical path direction of the light source.

2. The projection system with switchable light emission modes according to claim 1, wherein: The driving mechanism includes a rotary motor connected to the center of the color wheel.

3. The projection system with switchable light-emitting modes according to claim 2, wherein: The heat dissipation region is the inner ring of the color wheel, and the yellow fluorescent region and the color fluorescent region are located on the periphery of the heat dissipation region.

4. The projection system with switchable light emission modes according to claim 2, wherein: A number of fan blades are arranged in a circumferential array in the heat dissipation region.

5. The projection system with switchable light emission modes as claimed in claim 3, wherein: The driving mechanism further includes an offset motor and a transmission assembly connected to the offset motor. The transmission assembly is connected to the rotary motor, and the transmission assembly converts the output motion of the offset motor into the translational motion of the rotary motor.

6. The projection system with switchable light emission modes according to claim 5, characterized in that: The transmission assembly includes two fixedly arranged mounting plates, a screw rod, and a guide rod located between the two mounting plates. The screw rod is rotatably matched with the mounting plate. The offset motor is connected to the screw rod, and the rotary motor passes through the guide rod and is threadedly connected to the screw rod.

7. The projection system with switchable light emission modes according to claim 5, characterized in that: The transmission assembly includes a connecting rod, a cam, two fixedly arranged mounting plates, and a guide rod located between the two mounting plates. The rotary motor passes through the guide rod. The offset motor drives the cam to rotate. One end of the connecting rod abuts against the outer edge of the cam, and the other end passes through the mounting plate and is connected to the rotary motor. An elastic resetting member is arranged between one side of the rotary motor and the mounting plate. The elastic resetting member and the connecting rod are located on both sides of the rotary motor.

8. The projection system with switchable light emission modes according to claim 1, characterized in that: The laser light source is a blue laser.

9. The projection system with switchable light-emitting modes according to claim 1, wherein: The color wheel is a transmissive color wheel. The emission direction of the laser light source is perpendicular to the plane of the color wheel. The first collimator and the second collimator are located on both sides of the color wheel.

10. The projection system with switchable light-emitting modes according to claim 1, characterized in that: The color wheel is a reflective color wheel. The emission direction of the laser light source is parallel to the plane of the color wheel. The first collimator and the second collimator are located at the same position. The projection system further includes a dichroic mirror that reflects the light beam from the laser light source to the first collimator and reflects the light beam from the second collimator to the free-form surface mirror.

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