A small volume wavelength conversion device and a light source device thereof

Abstract

The utility model discloses a small volume wavelength conversion device and light source device thereof belong to optical illumination technical field. Wavelength conversion device can convert the excitation light with first polarization state mostly into stimulated light, and change the polarization state of the remaining excitation light. The light source device contains the wavelength conversion device, excitation light source, dichroic mirror, shaping lens group and mirror. Through dichroic mirror, the light is split and combined based on polarization state and wavelength, and the unused excitation light is returned to the wavelength conversion device for recycling by using the mirror, thereby cancelling the independent blue light processing light path. The utility model effectively reduces the light source volume, reduces the cost, and is more easily adapted to the existing stage lamp structure.

Description

Technical Field

[0001] This utility model relates to the field of optical lighting technology, specifically to a laser-excited fluorescence light source device for stage lights, projectors and other equipment, and in particular to a small-volume, low-cost wavelength conversion device and a light source device including the device. Background Technology

[0002] Currently, stage lighting sources are transitioning from traditional halogen and xenon lamps to newer sources such as LED and laser light sources. Energy conservation, environmental protection, and intelligent technologies (such as digital control and networked systems) have become core directions for industry upgrades. LED light sources are limited in many applications due to their short illumination distance, while three-color lasers in laser light sources face challenges such as high cost, speckle, color separation, and potential laser hazards. Laser fluorescent white light source modules, due to their low cost, high collimation, and long-distance illumination advantages, occupy an important position in the stage lighting beam light industry.

[0003] Existing laser phosphor light sources use blue light to excite yellow phosphors or fluorescent ceramics to produce yellow light, which is then mixed with the remaining blue light to form white light. These primarily employ either transmission or reflection schemes. Transmission schemes are less efficient, cannot support high-power lasers, and have a longer optical path, resulting in a larger size and limiting product applications. The most common reflection scheme uses a dichroic mirror to proportionally split the excitation light. Most of the blue light is excited and converted into yellow light, while a small portion of the blue light is separated, diffusely reflected, and returns to the dichroic mirror to combine with the yellow light to form white light. For example... Figure 1 The existing light source architecture shown splits the excitation light into two paths via a beam splitter / combiner. One path excites a fluorescent component, generating excited light which is reflected by the fluorescent component to the beam splitter. The other path is reflected by a reflector to form a second laser. The beam splitter / combiner then combines the excited light and the second laser to form the emitted light from the light source. The beam splitter / combiner uses a proportional coating or a regional coating method to split the blue light. Because the blue light needs to be proportionally split beforehand, this approach requires a separate optical path shaping system for the split blue light, increasing cost and light source size. The subsequent combination with the fluorescent light further increases the light source size and cost. While a projector-style blue light path that loops around the light source, and a reflective yellow light path, can achieve color temperature consistency, this increases size and cost. Furthermore, it is prone to screen flickering when photographed with a mobile phone, failing to meet the requirements of stage lights and cultural tourism beams.

[0004] In addition, the stage lighting market mostly uses generic mold shells and bulbs and LED light sources. These light sources are generally small in size. Existing laser light sources are too large to directly replace the original bulbs or LED light sources. New molds need to be made. Moreover, the light sources are too big and heavy, which is not conducive to heat dissipation and the realization of a stable stage light movement, thus limiting their market application.

[0005] Therefore, there is an urgent need for a laser fluorescent light source solution that is smaller, lower in cost, and compatible with existing stage lighting structures. Utility Model Content

[0006] The technical problem to be solved by this invention is to provide a small-volume wavelength conversion device that can efficiently convert wavelengths and change the polarization state of excitation light.

[0007] Another technical problem to be solved by this utility model is to provide a light source device including the above-mentioned wavelength conversion device. This light source device eliminates the independent blue light processing optical path through ingenious optical path design and polarization state control, so as to reduce the overall size and reduce manufacturing costs.

[0008] To solve the above-mentioned technical problems, this utility model adopts the following technical solution:

[0009] In a first aspect, this utility model proposes a small-volume wavelength conversion device, comprising:

[0010] Thermally conductive substrate;

[0011] Reflective structures; and

[0012] Wavelength conversion structure layer;

[0013] The wavelength conversion structure layer and the reflective structure are stacked on the thermally conductive substrate along the incident path of the excitation light, and the wavelength conversion structure layer is closer to or farther away from the incident side of the excitation light than the reflective structure.

[0014] The wavelength conversion device is configured to: receive excitation light having a first polarization state, convert most of it into laser light, and change the polarization state of the remaining excitation light to a second polarization state different from the first polarization state.

[0015] Furthermore, the small-volume wavelength conversion device proposed in this utility model comprises, in sequence from the direction of excitation light incident, the wavelength conversion structure layer, the reflective structure, and the thermally conductive substrate; the wavelength conversion structure layer is configured to convert the wavelength of 65%-90% of the excitation light; the reflective structure is configured to diffusely reflect the laser-induced and unconverted excitation light, and to convert the polarization state of the unexcited portion or all of the first polarization state excitation light.

[0016] Furthermore, the small-volume wavelength conversion device proposed in this utility model comprises, in sequence from the direction of excitation light incident, the reflection structure, the wavelength conversion structure layer, and the thermally conductive substrate; the reflection structure is a diffuse reflection structure layer, the thickness of which is less than that of the wavelength conversion structure layer, and is configured to diffusely reflect 10%-35% of the excitation light (this process will change all or part of this part of the excitation light to a first polarization state), and the remaining excitation light penetrates to the wavelength conversion structure layer for wavelength conversion; a high-reflection layer or another diffuse reflection layer is disposed on the thermally conductive substrate for reflecting the laser light.

[0017] Furthermore, in the small-volume wavelength conversion device proposed in this utility model, the wavelength conversion structure layer is a 360° continuous circular ring structure.

[0018] On the other hand, this utility model proposes a light source device, comprising:

[0019] Such as the wavelength conversion device proposed in this utility model;

[0020] An excitation light source is used to emit excitation light with a first polarization state;

[0021] Dichroic mirrors are configured to split and combine light based on the polarization state and wavelength of the light.

[0022] A shaping lens assembly, disposed between the dichroic mirror and the wavelength conversion device, is used to converge and shape the light path; and

[0023] The first reflecting mirror is located between the excitation light source and the dichroic mirror;

[0024] The optical path is configured as follows: the first polarized excitation light emitted by the excitation source is reflected or transmitted through the dichroic mirror and then guided by the shaping lens group to the wavelength conversion device; the laser-induced and second polarized excitation light generated by the wavelength conversion device passes through the shaping lens group, is transmitted or reflected through the dichroic mirror, enters the output lens, and exits; the unconverted first polarized excitation light is guided by the dichroic mirror to the first reflecting mirror, and is reflected back to the dichroic mirror by the first reflecting mirror, and re-enters the shaping lens group and the wavelength conversion device for recycling, until all excitation light is converted or exits through the output lens.

[0025] Furthermore, in the light source device proposed in this utility model, the first reflector is configured to be perpendicular to the optical axis of the first polarized excitation light, with a portion of the region transmitting the first polarized excitation light and another portion of the region reflecting the first polarized excitation light, and the area of ​​the reflected region being greater than or equal to the area of ​​the transmitted region.

[0026] Furthermore, in the light source device proposed in this utility model, the first reflector is set at a 45° angle to the optical axis of the first polarized excitation light and parallel to the dichroic mirror; the dichroic mirror is provided with a regional coating, a part of which is used to reflect or transmit the first polarized excitation light, and another part transmits or reflects the second polarized excitation light, and allows all visible light with wavelengths greater than the excitation light to be transmitted or reflected.

[0027] Furthermore, the light source device proposed in this utility model also includes a polarization conversion system, which includes a first polarization converter, a second polarization converter, and a second reflector; the second polarization converter and the second reflector are sequentially located on one side of the dichroic mirror, and the first polarization converter, the first reflector, and the excitation light source are sequentially arranged on the other side of the dichroic mirror.

[0028] The dichroic mirror guides the unconverted first polarization excitation light to the first polarization converter and the first reflector, converting it into a second polarization excitation light and returning it to the dichroic mirror for emission. The second polarization excitation light is converted back into a first polarization excitation light by the second polarization converter and the second reflector, and then incident on the dichroic mirror. The dichroic mirror guides this portion of the first polarization excitation light into the light-emitting lens, and then it is emitted outside the light source.

[0029] Furthermore, in the light source device proposed in this utility model, the first polarization converter and the second polarization converter are quarter-wave plates.

[0030] Furthermore, the light source device proposed in this invention also includes a third polarization converter disposed in the optical path of the first reflecting mirror, used to convert the first polarization state excitation light reflected by the first reflecting mirror into a second polarization state excitation light, which is then emitted through the dichroic mirror. The third polarization converter is a half-wave plate.

[0031] Finally, this utility model also proposes a light source device, comprising:

[0032] The wavelength conversion device as described in this utility model;

[0033] An excitation light source is used to emit excitation light with a first polarization state;

[0034] Dichroic mirrors are configured to split and combine light based on the polarization state and wavelength of the light.

[0035] A shaping lens assembly, disposed between the dichroic mirror and the wavelength conversion device, is used to converge and shape the light path; and

[0036] A first reflecting mirror; the first reflecting mirror is located between the dichroic mirror and the shaping lens group, and the first reflecting mirror is provided with a regional coating, a portion of which transmits the first polarized excitation light and the received laser, and another portion of which reflects the first polarized excitation light and transmits the second polarized excitation light and the received laser.

[0037] The first polarized excitation light emitted by the excitation source is reflected or transmitted by the dichroic mirror, then sequentially incident on the first emitting mirror and projected through it. It is then guided by the shaping lens group to the wavelength conversion device. The light converted by the wavelength conversion device is collected and shaped by the shaping lens group and then incident on the first reflecting mirror. The laser and the second polarized excitation light reach the dichroic mirror through the first reflecting mirror. The dichroic mirror guides this part into the exiting lens for emission. Most or all of the first polarized excitation light that has not been converted is reflected back to the wavelength conversion device for conversion and polarization change until all the excitation light is converted or emitted through the exiting lens.

[0038] Compared with the prior art, the present invention, by adopting the above technical solution, has the following technical effects:

[0039] 1. Significantly reduced size: By using a wavelength conversion device to change the polarization state and combining it with the polarization and beam splitting function of a dichroic mirror, the independent blue light processing optical path in the existing technology has been successfully eliminated, making the light source structure more compact and compatible with existing stage lighting molds.

[0040] 2. Effective cost reduction: The simplification of the optical path reduces the need for expensive optical lenses (by nearly half) and complex beam splitting elements, thereby reducing material and assembly costs.

[0041] 3. Performance optimization: Recycling the excitation light improves the light efficiency, while the simplified structure is more conducive to heat dissipation design and enables the stage light to move smoothly. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of an existing light source solution.

[0043] Figure 2 This is a schematic diagram of the wavelength conversion device of this utility model.

[0044] Figure 3 This is a schematic diagram of one arrangement of the reflector in this utility model.

[0045] Figure 4 This is a schematic diagram of the light source optical path in Embodiment 1 of this utility model.

[0046] Figure 5 This is a schematic diagram of the light source optical path in Embodiment 2 of this utility model.

[0047] Figure 6 This is a schematic diagram of the light source optical path in Embodiment 3 of this utility model.

[0048] Figure 7 This is a schematic diagram of the light source optical path in Embodiment 4 of this utility model.

[0049] Figure 8 This is a schematic diagram of the light source optical path in Embodiment 5 of this utility model. Detailed Implementation

[0050] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings:

[0051] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless defined as herein.

[0052] This invention proposes a small-volume wavelength conversion device and its light source device. It adopts a special wavelength conversion device and light source optical path design, utilizes the special optical coating of dichroic mirrors, and combines it with the structural design of optical elements to solve the problem of independent blue light path design, while reducing the size of the light source; reducing the number of expensive optical lenses used, and lowering costs.

[0053] refer to Figure 2 This invention proposes a small-volume wavelength conversion device, which includes a motor for power supply, a heat-conducting substrate, a reflective structure layer, and a wavelength conversion structure layer. The wavelength conversion structure layer is a continuous 360° circular ring, and the wavelength conversion structure layer and the reflective structure layer are stacked together. The wavelength conversion device converts most of the excitation light emitted by the excitation source into laser light, and changes the polarization state of the remaining excitation light to be different (or not completely the same) from the polarization state emitted by the excitation source.

[0054] (1) From the direction of excitation light incident, if the wavelength conversion structure layer, the reflection structure, and the thermally conductive substrate are set in sequence, the wavelength conversion structure layer is set to convert 65%-90% of the excitation light wavelength, and the reflection structure layer is set to diffusely reflect all the laser light and the unexcited excitation light, so as to achieve a light output color temperature of 6000K-12000K.

[0055] (2) If the excitation light incident direction is set as a reflective structure layer, a wavelength conversion structure layer and a thermally conductive substrate in sequence, then the reflective structure layer is a diffuse reflection structure layer and its thickness is less than that of the wavelength conversion structure layer. It can diffusely reflect 10%-35% of the excitation light to achieve a light output color temperature of 6000K-12000K. The remaining excitation light penetrates the diffuse reflection structure layer to the wavelength conversion structure layer, performs wavelength conversion, and forms a laser. At this time, the thermally conductive substrate has a high reflectivity or another diffuse reflection structure layer is set on the thermally conductive substrate to reflect the laser.

[0056] refer to Figure 4 As shown, this utility model also proposes a light source device, which includes a wavelength conversion device, an excitation light source, a dichroic mirror, a shaping lens group, a reflector 1, and a light-emitting lens.

[0057] Example 1: The excitation light emitted by the excitation source is set to the same polarization state. The dichroic mirror is configured to transmit (reflect) the excitation light emitted by the laser and the excitation light with a polarization state different from that emitted by the excitation source (second polarization state), and reflect the light emitted by the excitation source in the initial polarization state (first polarization state). If the first polarization state is S-polarization, the dichroic mirror has the function of reflecting the excitation light of the first polarization state; if the first polarization state is P-polarization, the dichroic mirror has the function of transmitting the excitation light of the first polarization state. The reflector 1 is configured to be perpendicular to the optical axis of the excitation light of the first polarization state, and preferably is positioned between the excitation source and the dichroic mirror. The reflector 1 is configured to transmit the excitation light emitted by the excitation source in the first polarization state and reflect the excitation light in the second polarization state.

[0058] The light source device has the following optical path configuration: the excitation light source emits excitation light with a first polarization state having a single polarization state. This excitation light is incident on a dichroic mirror, which reflects or transmits the first polarization state excitation light and guides it to a shaping lens group. The shaping lens group converges and guides this portion of the excitation light to a wavelength conversion device. The wavelength conversion device converts most of the received excitation light into a yellow laser light, while converting or partially converting the first polarization state of the remaining unconverted excitation light, forming light with similar emission characteristics to the yellow laser light (such as emission angle, spot size, etc.). The yellow laser beam and the remaining excitation light after passing through the wavelength conversion device (including excitation light with and without polarization conversion) are collected by the shaping lens group in front of the wavelength conversion device, forming a roughly parallel beam that is incident on the dichroic mirror. The yellow laser beam and the second polarization excitation light are transmitted or reflected through the dichroic mirror into the light-emitting lens of the light source. The first polarization excitation light that has not been polarized is guided in whole or in part to the reflecting mirror 1. The reflecting mirror 1 reflects it back to the dichroic mirror, which then guides it again to the shaping lens group and the wavelength conversion device, and repeats the previous steps until all the excitation light is converted or reaches the light-emitting lens of the light source.

[0059] Example 2: Reference Figure 5 As shown, the reflector 1 can also be positioned between the dichroic mirror and the shaping lens group. In this configuration, the reflector 1 has a localized coating, such as... Figure 3 As shown, a portion of the reflector 1 transmits the first polarization excitation light and the laser beam, while another portion reflects the first polarization excitation light. The light, after passing through the wavelength conversion device, is shaped by the shaping lens group and then incident on the reflector 1. Most or all of the first polarization excitation light is reflected back to the wavelength conversion device for conversion and polarization change. The laser beam and the second polarization excitation light pass through the reflector 1 to reach the dichroic mirror, which guides this portion into the light-emitting lens group of the light source.

[0060] Example 3: Reference Figure 6 As shown, unlike embodiments 1 and 2, the light source may also include a reflector 2 and polarization converters 1 and 2. The polarization converters 2 and reflector 2 are located on one side of the dichroic mirror, while the other side of the dichroic mirror contains the excitation light source, reflector 1, and polarization converter 1. The polarization converters 1 and 2 are quarter-wave plates used to convert the polarization state of light passing through them. The reflector 1 and reflector 2 reflect the light passing through the polarizer without changing its polarization state. The dichroic mirror guides the excitation light that has not been converted to the second polarization state after passing through the wavelength conversion device to the polarization converter 1. The polarization converter 1 guides it to the reflector 1, which reflects it back to the polarization converter 1. At this point, this portion of light becomes second-polarization state excitation light and is transmitted (or reflected) through the dichroic mirror. This second-polarization state excitation light is sequentially incident on the polarization converter 2, reflector 2, and polarization converter 1, becoming first-polarization state excitation light again, and then incident on the dichroic mirror. The dichroic mirror reflects (or transmits) the first-polarization state excitation light, guides it to the light-emitting lens of the light source, and then emits it.

[0061] Example 4: Reference Figure 7 As shown, unlike the previous embodiment, the reflector 1 is positioned at a 45° angle to the optical axis of the first polarized excitation light (parallel to the dichroic mirror). The dichroic mirror reflects (transmits) all or part of the first polarized excitation light emitted from the wavelength conversion device and guides it onto the reflector 1. The reflector 1 then guides this portion through the dichroic mirror to the output lens, where it is emitted. The dichroic mirror is configured with a partial coating, where a portion reflects or transmits the first polarized excitation light and is used to transmit or reflect both laser and second polarized excitation light, while another portion is configured to allow transmission of visible light.

[0062] Example 5: Reference Figure 8As shown, unlike Embodiment 4, the reflector 1 is positioned at a 45° angle to the optical axis of the first polarized excitation light (parallel to the dichroic mirror), and a polarization converter 3 is positioned between the reflector 1 and the dichroic mirror. The dichroic mirror reflects (transmits) all or part of the first polarized excitation light returning from the wavelength conversion device and guides it onto the reflector 1. The reflector 1 then guides this portion of light onto the polarization converter 3, which is a half-wave plate. This portion of light is converted into second polarized excitation light after passing through the polarization converter 3, and then incident on the dichroic mirror. It is then transmitted or reflected by the dichroic mirror and guided to the exit lens before exiting. The dichroic mirror is configured to reflect or transmit the first polarized excitation light, and to transmit or reflect both the laser light and the second polarized excitation light.

[0063] In summary, the present invention can reduce the use of optical lenses by nearly half, thereby reducing costs; it can eliminate the blue light path, reduce the size of the light source, and reduce costs; at the same time, it can be more widely adapted to existing bulb light sources and LED light source stage lighting products, and the space saved can be further used to realize heat dissipation design of the light source.

[0064] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. A small volume wavelength conversion device, characterized by, include: Thermally conductive substrate; Reflective structure; as well as Wavelength conversion structure layer; The wavelength conversion structure layer and the reflective structure are stacked on the thermally conductive substrate along the incident path of the excitation light, and the wavelength conversion structure layer is closer to or farther away from the incident side of the excitation light than the reflective structure. The wavelength conversion device is configured to: receive excitation light having a first polarization state, convert most of it into laser light, and change the polarization state of the remaining excitation light to a second polarization state different from the first polarization state.

2. The small volume wavelength conversion device of claim 1, wherein, The wavelength conversion structure layer is closer to the excitation light incident side than the reflection structure, and the wavelength conversion structure layer is configured to convert the wavelength of 65%-90% of the excitation light; the reflection structure is configured to diffusely reflect the laser-induced and unconverted excitation light, and to convert the polarization state of the unexcited portion or all of the first polarization state excitation light.

3. The small volume wavelength conversion device of claim 1, wherein, The reflective structure is closer to the excitation light incident side than the wavelength conversion structure layer; the reflective structure is a diffuse reflection structure layer with a thickness less than the wavelength conversion structure layer, and is configured to diffusely reflect 10%-35% of the excitation light, with the remaining excitation light penetrating to the wavelength conversion structure layer for wavelength conversion; a high reflective layer or another diffuse reflection layer is further provided on the thermally conductive substrate for reflecting the laser light.

4. The small volume wavelength conversion device of any of claims 1 to 3, wherein, The wavelength conversion structure layer is a continuous circular ring structure with a 360° angle.

5. A light source apparatus, characterized by comprising: include: The wavelength conversion device as described in any one of claims 1 to 4; An excitation light source is used to emit excitation light with a first polarization state; Dichroic mirrors are configured to split and combine light based on the polarization state and wavelength of the light. A shaping lens group is disposed between the dichroic mirror and the wavelength conversion device, and is used to converge and shape the light path; as well as The first reflecting mirror is located between the excitation light source and the dichroic mirror; The optical path is configured as follows: the first polarized excitation light emitted by the excitation source is reflected or transmitted through the dichroic mirror and then guided by the shaping lens group to the wavelength conversion device; the laser-induced and second polarized excitation light generated by the wavelength conversion device passes through the shaping lens group, is transmitted or reflected through the dichroic mirror, enters the output lens, and exits; the unconverted first polarized excitation light is guided by the dichroic mirror to the first reflecting mirror, and is reflected back to the dichroic mirror by the first reflecting mirror, and re-enters the shaping lens group and the wavelength conversion device for recycling, until all excitation light is converted or exits through the output lens.

6. The light source apparatus according to claim 5, wherein The first reflector is configured to be perpendicular to the optical axis of the first polarized excitation light, with a portion of the region transmitting the first polarized excitation light and another portion of the region reflecting the first polarized excitation light, and the area of ​​the reflected region being greater than or equal to the area of ​​the transmitted region.

7. The light source apparatus according to claim 5, wherein The first reflector is configured to be at a 45° angle to the optical axis of the first polarized excitation light and parallel to the dichroic mirror; the dichroic mirror is provided with a regional coating, a part of which is used to reflect or transmit the first polarized excitation light, and another part transmits or reflects the second polarized excitation light, and allows all visible light with wavelengths greater than the excitation light to be transmitted or reflected.

8. The light source apparatus according to claim 5, wherein It also includes a polarization conversion system, which includes a first polarization converter, a second polarization converter, and a second reflector; the second polarization converter and the second reflector are located on one side of the dichroic mirror, and the first polarization converter, the first reflector, and the excitation light source are arranged on the other side of the dichroic mirror. The dichroic mirror guides the unconverted first polarization excitation light to the first polarization converter and the first reflector, converting it into a second polarization excitation light and returning it to the dichroic mirror for emission. The second polarization excitation light is converted back into a first polarization excitation light by the second polarization converter and the second reflector, and then incident on the dichroic mirror. The dichroic mirror guides this portion of the first polarization excitation light into the light-emitting lens, and then it is emitted outside the light source.

9. The light source apparatus according to claim 8, wherein The first polarization converter and the second polarization converter are quarter-wave plates.

10. The light source apparatus according to claim 7, wherein It also includes a third polarization converter disposed in the optical path of the first reflector, used to convert the first polarization state excitation light reflected by the first reflector into the second polarization state excitation light, and then emit it through the dichroic mirror.

11. The light source apparatus according to claim 10, wherein The third polarization converter is a half-wave plate.

12. A light source apparatus, characterized by comprising: include: The wavelength conversion device as described in any one of claims 1 to 4; An excitation light source is used to emit excitation light with a first polarization state; Dichroic mirrors are configured to split and combine light based on the polarization state and wavelength of the light. A shaping lens group is disposed between the dichroic mirror and the wavelength conversion device, and is used to converge and shape the light path; as well as First reflecting mirror; The first reflecting mirror is located between the dichroic mirror and the shaping lens group, and a regional coating is provided on the first reflecting mirror. A portion of the coating transmits the first polarized excitation light and the received laser light, while another portion reflects the first polarized excitation light and transmits the second polarized excitation light and the received laser light. The first polarized excitation light emitted by the excitation source is reflected or transmitted by the dichroic mirror, then sequentially enters the first emitting mirror and is projected through it, and is then guided to the wavelength conversion device by the shaping lens group. After being converted by the wavelength conversion device, the light is collected and shaped by the shaping lens group and then incident on the first reflecting mirror. The light excited by the laser and the second polarization state passes through the first reflecting mirror and reaches the dichroic mirror. The dichroic mirror guides this part into the exiting lens for emission. Most or all of the first polarization state excitation light that has not been converted is reflected back to the wavelength conversion device for conversion and polarization state change until all excitation light is converted or emitted through the exiting lens.

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