WO2021184924A1

WO2021184924A1 - Light source system and projection equipment

Info

Publication number: WO2021184924A1
Application number: PCT/CN2020/142138
Authority: WO
Inventors: 陈晨; 胡飞; 余新; 李屹
Original assignee: 深圳光峰科技股份有限公司
Priority date: 2020-03-19
Filing date: 2020-12-31
Publication date: 2021-09-23
Also published as: CN113495412A

Abstract

A light source system (100) and projection equipment (200). The light source system (100) comprises a light source apparatus (10), a wavelength conversion apparatus (40), an optical device (20), and a light splitting and combining unit (30). The light source apparatus (10) is used to emit excitation light. The wavelength conversion apparatus (40) is used to at least partially convert received excitation light into excited light. The light source apparatus (10) and the wavelength conversion apparatus (40) are provided on two adjacent side surfaces of the optical device (20), respectively. The light splitting and combining unit (30) is provided inside of the optical device (20). The excitation light enters the optical device (20) and is incident to the light splitting and combining unit (30). The light splitting and combining unit (30) reflects the received excitation light to the wavelength conversion apparatus (40). The excited light emitted by the wavelength conversion apparatus (40) enters the optical device (20). A part of the excited light is transmitted by means of the light splitting and combining unit (30) and emitted from the optical device (20), and the rest of the excited light passes through the optical device (20) surrounding the light splitting and combining unit (30), and is emitted from the optical device (20). The light source system (100) helps to increase brightness.

Description

Light source system and projection equipment

Technical field

The present invention relates to the field of projection technology, in particular to a light source system and projection equipment.

Background technique

At present, the laser fluorescent light source is widely used in various projection equipment due to its advantages of long life, low cost, and high brightness, and has a very good display effect. An important point in the laser fluorescence technology is the fluorescence excitation scheme and the fluorescence and laser light combining scheme. The development of more efficient and compact fluorescence excitation schemes and fluorescence laser light combining schemes is of great significance to the development of laser fluorescence technology.

In the fluorescence excitation and collection schemes used in the prior art, a dichroic plate is usually used to reflect short-wavelength excitation light and transmit long-wavelength fluorescence to realize the splitting and combining of laser light and fluorescence. In order to ensure the uniformity of the translation of the fluorescent beam and avoid the scattering of light by the edge of the dichroic film, it is necessary to ensure that the dichroic film can cover all the fluorescent areas. Therefore, the area of the dichroic film needs to be relatively large, so that the fluorescence can pass through the collecting lens. After the group, the propagation distance is too long, which causes the optical expansion of the fluorescence to be diluted, which is not conducive to the improvement of the brightness of the laser fluorescent light source.

Summary of the invention

The present invention proposes a light source system and projection equipment to solve the above problems.

The embodiments of the present invention achieve the above objectives through the following technical solutions.

In the first aspect, an embodiment of the present invention provides a light source system. The light source system includes a light source device, a wavelength conversion device, an optical device, and a light splitting and combining unit; the light source device is used to emit excitation light, and the wavelength conversion device is used to combine the received excitation light. The light source device and the wavelength conversion device are respectively arranged on two adjacent sides of the optical device, and the light splitting and combining unit is arranged inside the optical device; the excitation light enters the optical device and is incident to the light splitting and combining unit, and the The photosynthetic light unit reflects the received excitation light to the wavelength conversion device. The received laser light emitted by the wavelength conversion device enters the optical device. Part of the received laser light passes through the light splitting unit and exits the optical device. The rest of the received laser light passes through the surrounding light splitting unit. Optical device, emitting from the optical device.

In an embodiment, the light splitting and combining unit is arranged obliquely with respect to the optical path of the excitation light emitted by the light source device.

In one embodiment, the optical device includes a first surface, a second surface, and a third surface that are connected, and the first surface and the third surface are arranged relatively parallel, the wavelength conversion device faces the first surface, and the light source device faces the second surface , The laser is emitted from the third surface.

In one embodiment, the area of the orthographic projection of the light splitting and combining unit on the first surface is smaller than the area of the first surface.

In one embodiment, the area of the orthographic projection of the light splitting and combining unit on the first surface is located in the middle area of the first surface.

In one embodiment, the optical device is a hollow cuboid prism, the light splitting and combining unit is a light splitting sheet, the light splitting sheet is arranged inside the optical device, and the light splitting sheet reflects the excitation light and transmits the received laser light.

In one embodiment, the optical device is a rectangular parallelepiped prism formed by combining two right-angle trapezoidal prisms, the slopes of the two right-angle trapezoidal prisms are joined together, and the light splitting and combining unit is arranged at the joint of the two right-angle trapezoidal prisms.

In one embodiment, the light splitting and combining unit is a light splitting sheet sandwiched between two right-angle trapezoidal prisms, and the light splitting sheet reflects the excitation light and transmits the received laser light.

In one embodiment, the light splitting and combining unit is an optical coating formed on the inclined surface of at least one right-angled trapezoidal prism, and the optical coating reflects the excitation light and transmits the received laser light.

In one embodiment, the distance between the first surface and the third surface is equal to the shortest edge length of the cuboid prism.

In one embodiment, the light source device emits excitation light in the first polarization state, and the received laser light is unpolarized light, and the light splitting and combining unit reflects the excitation light in the first polarization state and transmits the excitation light in the first polarization state and the excitation light in the second polarization state.

In one embodiment, the light source system further includes a supplementary light source, the supplementary light source is used to emit supplementary light in the first polarization state, the supplementary light and the excitation light have the same color; the supplementary light source is arranged on a side of the optical device that is away from the light source device , The supplementary light emitted by the supplementary light source enters the optical device and is incident on the light splitting and combining unit, and the supplementary light is reflected by the light splitting and combining unit and exits the optical device along the same optical path as the received laser light.

In one embodiment, the optical device is a rectangular parallelepiped prism formed by combining two right-angle trapezoidal prisms. The slopes of the two right-angle trapezoidal prisms are combined. The slopes of the two right-angle trapezoidal prisms are both provided with an optical coating. The optical coating reflects The excitation light and the supplementary light in the first polarization state are transmitted through the laser light and the excitation light in the second polarization state.

In a second aspect, an embodiment of the present invention provides a projection device, and the projection device includes the light source system of any one of the foregoing embodiments.

In the light source system and projection equipment provided by the present invention, a part of the received laser light is transmitted through the light splitting and combining unit and then emitted from the third surface, and the remaining part of the received laser light is emitted from the third surface after passing through the optical device around the light splitting and combining unit. The volume of the optical device is small, thereby reducing the dilution of the optical expansion of the received laser light during the propagation process, which is beneficial to improve the brightness of the light source system.

Description of the drawings

In order to explain the technical solutions in the embodiments of the present invention more clearly, the following will briefly introduce the drawings needed in the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

Fig. 1 is a schematic structural diagram of a light source system provided by an embodiment of the present invention.

FIG. 2 is a schematic diagram of the structure of the optical device and the light splitting and combining unit of the light source system of FIG. 1.

FIG. 3 is a schematic structural diagram of another embodiment of the optical device and the light splitting and combining unit of the light source system of FIG. 1.

Fig. 4 is a schematic diagram of estimating the offset of the dichroic film provided in the prior art.

Fig. 5 is a schematic diagram of estimating the optical expansion of the dichroic film provided in the prior art.

Fig. 6 is a schematic diagram of estimating the optical expansion of the light source system of Fig. 1.

FIG. 7 is a schematic structural diagram of a light source system provided by another embodiment of the present invention.

FIG. 8 is a schematic diagram of the characteristics of the optical coating of the light source system of FIG. 7.

FIG. 9 is a schematic diagram of the characteristics of another optical coating of the light source system of FIG. 7.

FIG. 10 is a schematic diagram of the characteristics of yet another optical coating of the light source system of FIG. 7.

FIG. 11 is a schematic structural diagram of a light source system provided by another embodiment of the present invention.

Fig. 12 is a schematic structural diagram of a projection device provided by an embodiment of the present invention.

Detailed ways

In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be described clearly and completely in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work shall fall within the protection scope of the present invention.

Referring to FIG. 1, an embodiment of the present invention provides a light source system 100. The light source system 100 includes a light source device 10, a wavelength conversion device 40, an optical device 20, and a light splitting and combining unit 30. The light source device 10 is used to emit excitation light, and the wavelength conversion device 40 is used to at least partially convert the received excitation light into received laser light.

The light source device 10 and the wavelength conversion device 40 are respectively arranged on two adjacent sides of the optical device 20, and the light splitting and combining unit 30 is arranged inside the optical device 20. The excitation light emitted by the light source device 10 enters the optical device 20 and is incident on the light splitting and combining unit 30. The light splitting and combining unit 30 reflects the received excitation light to the wavelength conversion device 40, and the wavelength conversion device 40 at least partially converts the received excitation light The received laser light emitted by the wavelength conversion device 40 enters the optical device 20, part of the received laser light is transmitted through the light splitting and light combining unit 30 and emitted from the optical device 20, and the rest of the received laser light passes through the optical device 20 around the light splitting and light combining unit 30, from The optical device 20 exits.

Specifically, the light source device 10 refers to a light source that can emit light for exciting the wavelength conversion material, and the light source device 10 can be a laser diode (Laser Diode) light source or a light emitting diode (Light Emitting Diode) light source to emit excitation light. The excitation light emitted by the light source device 10 may be blue light, purple light, red light, green light, ultraviolet light, or other types of light, which are not listed here. In this embodiment, the light source device 10 includes a blue semiconductor laser diode, and the light source device 10 emits blue laser light as excitation light. The number of blue semiconductor laser diodes can be one or more than one. A plurality of blue semiconductor diodes may form a semiconductor diode array.

In one embodiment, the blue semiconductor laser diode is a gallium nitride-based blue laser. The luminous efficiency and production cost of the gallium nitride-based blue laser are low, and it also overcomes the poor thermal stability of red laser materials and the efficiency of green lasers. Due to the limitation of low life and short life, the red-green spectrum can be realized with the wavelength conversion device 40.

The wavelength conversion device 40 is located on the optical path where the excitation light reflected by the light splitting and combining unit 30 is located, and is respectively disposed on two adjacent sides of the optical device 20 with the light source device 10. The wavelength conversion device 40 is provided with a wavelength conversion material layer (not shown) to convert the received excitation light into at least part of the received laser light. The excitation light and the received laser light are relative concepts, and the excitation light means that the wavelength conversion material layer can be excited. The wavelength conversion material produces light of different wavelengths. The laser light refers to the light generated by the excitation light of the wavelength conversion material layer. For example, blue light excites the yellow light conversion material layer to generate yellow light. At this time, the blue light is the excitation light, and the yellow light is the received laser light. The yellow light excites the red conversion material layer to generate red light. At this time, the yellow light is the excitation light and the red light is the received laser light. The blue light excites the green light conversion material layer to generate green light. At this time, the blue light is the excitation light and the green light is the received laser light.

The wavelength conversion material may include phosphorescent materials, such as phosphors, or nanomaterials, such as quantum dots, or fluorescent materials, which are not listed here. In one embodiment, the wavelength conversion material includes a fluorescent material, and the laser light emitted by the wavelength conversion device 40 is fluorescent. In this way, because the fluorescence is incoherent light, there is no speckle effect of the laser, and the blue light is used to excite the fluorescence. The material generates green fluorescence and red fluorescence, which can avoid the speckle problem of human vision caused by the coherence of the excitation light emitted by the light source device 10.

The wavelength conversion device 40 is provided with a heat dissipation device (not shown), such as a heat dissipation fin, for heat dissipation. The heat dissipation device may be provided on the surface of the wavelength conversion device 40 opposite to the light emitting surface. By using the heat dissipation device to export the excess heat to the surrounding environment, the temperature of the wavelength conversion material layer will not increase excessively and affect the luminous efficiency of the wavelength conversion device 40.

The optical device 20 is located at the intersection of the optical path of the excitation light emitted by the light source device 10 and the optical path of the laser light emitted by the wavelength device device 40, and the optical device 20 is spaced apart from the light source device 10 and the wavelength conversion device 40, respectively. In this embodiment, the optical device 20 is a prism body, and the optical device 20 can transmit excitation light and received laser light. The optical device 20 includes a first surface 21, a second surface 22, a third surface 23, and a fourth surface 24 that are connected, and the first surface 21 and the third surface 23 are relatively parallel, and the second surface 22 and the fourth surface 24 The light source device 10 faces the second surface 22, and the wavelength conversion device 40 faces the first surface 21. The excitation light emitted by the light source device 10 enters the optical device 20 through the first surface 21 and enters the light splitting and combining unit 30. The photosynthetic light unit 30 reflects the received excitation light to the wavelength conversion device 40; the received laser light emitted by the wavelength device device 40 enters the optical device 20 through the first surface 21, and part of the received laser light is transmitted through the light splitting and light combining unit 30 and passes through the third The surface 23 exits, and the remaining part of the received laser light passes through the optical device 20 around the light splitting and combining unit 30 and exits from the third surface 23.

In an embodiment, as shown in FIG. 2, the optical device 20 may be an integrally formed cuboid prism, and the cuboid prism is hollow. In other embodiments, as shown in FIG. 3, the optical device 20 may also be a rectangular parallelepiped prism formed by combining two right-angled trapezoidal prisms. The distance between the first surface 21 and the third surface 23 of the optical device 20 may be equal to the shortest edge length of the cuboid prism. In this way, the received laser light is transmitted through the cuboid prism from the direction of the shortest edge of the rectangular parallelepiped prism, which can reduce the propagation distance of the received laser light in the optical device 20, which is beneficial to reduce the dilution of the optical expansion of the light source system 100.

The light splitting and combining unit 30 is disposed inside the optical device 10, and the light splitting and combining unit 30 can reflect the excitation light and transmit the received laser light. Specifically, the light splitting and combining unit 30 reflects blue light and transmits red light, transmits green light, and transmits yellow light. In the case where the optical device 20 is a hollow cuboid prism, the light splitting and combining unit 30 may be a light splitting sheet, and the light splitting sheet is disposed in the hollow cavity of the optical device 20. In the case where the optical device 20 is a rectangular parallelepiped prism formed by combining two right-angle trapezoidal prisms, the light splitting and combining unit 30 may be a light splitting sheet, which is sandwiched between the two right-angled trapezoidal prisms; the light splitting and combining unit 30 is also It may be an optical coating 51, and the optical coating 51 may be formed on the slope of one of the right-angled trapezoidal prisms, or may be formed on the slopes of two right-angled trapezoidal prisms, respectively.

The optical device 20 cooperates with the light splitting and light combining unit 30 in the above manner, so that a part of the received laser light is transmitted through the light splitting and light combining unit 30 and then emitted from the third surface 23, and the remaining part of the received laser light passes through the optical device 20 around the light splitting and light combining unit 30. The third surface 23 emits light. In this way, the light splitting and combining unit 30 does not need to cover all the laser-receiving areas emitted by the wavelength conversion device 40, and can also maintain the uniformity of the translation of the laser-receiving light after transmitting the optical device 20, and also The dilution of the optical extension (Etendue) of the light source system 100 can be reduced, the ability of the light source system 100 to transmit light energy can be maintained, and the brightness of the light source system 100 can be improved.

Optical expansion is used in non-imaging optics to describe the geometric characteristics of a beam with a certain aperture angle and cross-sectional area. The optical expansion represents the integral of the area through which the beam passes and the solid angle occupied by the beam, namely Etendue≡n ² ∫∫cosθdAdΩ. Among them, θ is the angle between the normal of the area micro-element dA and the central axis of the solid-angle micro-element dΩ. For an ideal optical system that does not consider the energy loss caused by scattering and absorption, the optical expansion of the light beam remains conserved after passing through the ideal optical system. The optical expansion measures the change between the beam source area and the solid angle spread when the beam passes through the optical system. The larger the beam angle or the larger the area of the beam source, the greater the optical expansion obtained, and the lower the ability of the optical system to transmit light energy, which is not conducive to improving the brightness of the optical system.

The prior art adopts the dichroic sheet 200 (FIG. 4). When light enters the dichroic sheet 200 with a refractive index of n and a thickness of t at an oblique angle, a certain translation occurs in the incident surface, as shown in FIG. 4 Shown. Assuming that the incident angle of the light is θ, the translation amount of the light is

To further simplify:

It can be seen from the above formula that when n→1, the translation amount Δy(0; θ)→0. For general glass, the refractive index is about 1.5, so the obliquely incident light will always have a certain amount of translation after passing through the dichroic plate 200.

In the prior art, the dichroic plate 200 is used to ensure the uniformity of the received laser light translation, to prevent the obliquely incident received laser light from being partially displaced when passing through the dichroic plate 200, and part of the receiving laser light does not shift, and to avoid dichroic The edge of the sheet 200 causes the scattering of the received laser light, and the area of the dichroic sheet 200 needs to be expanded to cover all the laser-receiving areas emitted by the wavelength conversion device 40. However, it is easy to cause the optical extension of the light source system 100 to increase, which is not conducive to The brightness of the light source system 100 is improved.

The present invention uses the schematic diagrams of FIGS. 5 and 6 to estimate and compare the optical expansion obtained by the technical solutions of the prior art and this embodiment. Among them, the prior art adopts the dichroic film 200 (Figure 5). The embodiment adopts a form in which the optical device 20 cooperates with the light splitting and combining unit 30 (FIG. 6 ).

5, assuming that the spot size of the light emitted by the wavelength conversion device 40 at position A is D ₀ , the exit angle of the spot is θ ₀ , the divergence angle when the light exits is θ ₁ , and the light is transmitted through the dichroic plate 200 The spot size of position B is D ₁ , the distance between position A and position B is t ₁ , and the dichroic plate 200 is inclined at 45° with respect to the optical path of the incident light, then t ₁ =D ₀ +t ₁ tan(θ ₁ ),

Please refer to FIG. 6, assuming that the spot size of the light emitted by the wavelength conversion device 40 at the position A is D ₀ , the exit angle of the spot is θ ₀ , the divergence angle when the light exits is θ ₂ , and the light transmission optical device 20 combines light with the light splitter _{The spot size D 2} at the position B behind the unit 30, the distance between the position A and the position B is t ₂ , the refractive index of the optical device 20 is n, and the light splitting and combining unit 30 is inclined at 45° with respect to the optical path of the incident light. Then D ₂ =D ₀ +2t ₂ tan(θ ₂ ), assuming

Then D ₂ =D ₀ [1+tan(θ ₂ )], where sin(θ ₁ )=nsin(θ ₂ ).

Under normal circumstances, the divergence angle of light is not very large, so θ ₁ can be approximated as a small angle, then θ ₁ ≈sin(θ ₁ )≈tan(θ ¹ ), so:

The above-mentioned D ₁ and D ₂ are compared to estimate the degree of optical expansion dilution. For example, D ₁ and D _{2 can} be used as a difference or a quotient to compare the magnitude of the two values.

If D ₁ and D ₂ are compared by difference, then

Under normal circumstances, n≈1.5, which can be obtained by substituting in the calculation

It can be seen that when the light is emitted and there is a certain divergence angle, that is, when the divergence angle θ ₁ > 0, D _1- D ₂ > 0, it can be expressed that under the same conditions, the use of dichroic The spot area formed by the sheet 200 solution is larger than the solution in which the optical device 20 and the light splitting and combining unit 30 cooperate with each other in the embodiment of the present invention, which is not conducive to reducing the optical expansion of the light source system 100 and improving the brightness of the light source system 100.

If D ₁ and D ₂ are compared by quotient, then

Under normal circumstances, θ ₁ ≈3°, n≈1.5, substituting into the calculation can be obtained

It can be obtained that, under the same conditions, the solution of using the dichroic plate 200 in the prior art has an increased amount of optical expansion compared to the solution of the optical device 20 and the light splitting and combining unit 30 of the embodiment of the present invention. 14%.

Therefore, it can be seen from the above two comparison methods that the technical solution of the present invention can reduce the volume of the optical device 20, thereby reducing the dilution of the optical expansion of the received laser light during the propagation process, and is beneficial to improving the brightness of the light source system 100.

Please refer to FIG. 1, in an embodiment, the light source system 100 includes a light source device 10, a wavelength conversion device 40, an optical device 20, and a light splitting and combining unit 30. The optical device 20 is a rectangular parallelepiped prism formed by combining two right-angled trapezoidal prisms. The two right-angled trapezoidal prisms respectively have a first inclined surface 31 and a second inclined surface 32. The first inclined surface 31 and the second inclined surface 32 are combined by optical glue, namely , The first oblique surface 31 and the second oblique surface 32 of the two right-angle trapezoidal prisms are opposed to each other, and one of the right-angle trapezoidal prisms is turned upside down, so that the upper and lower bottom surfaces of one of the right-angle trapezoidal prisms are respectively opposite to the other The lower bottom surface and the upper bottom surface of the right-angle trapezoidal prism are flush, so that the first inclined surface 31 and the second inclined surface 32 of the two right-angled trapezoidal prisms are assembled into a rectangular parallelepiped prism through optical glue. In this way, the two right-angle trapezoidal prisms can be prevented from separating from each other when the light source system 100 is impacted by the outside, which is beneficial to improve the stability of the optical device 20 and ensure the normal operation of the light source system 100.

In this embodiment, the optical device 20 includes a first surface 21, a second surface 22, a third surface 23, and a fourth surface 24 that are connected, and the first surface 21 and the third surface 23 are relatively parallel, and the second surface 22 The first surface 21 is formed by connecting the bottom surface of one right-angled trapezoidal prism and the top surface of the other right-angled trapezoidal prism, and the third surface 23 is formed by the top surface of one of the right-angled trapezoidal prisms. Connected to the bottom surface of another right-angled trapezoidal prism, the second surface 22 and the fourth surface 24 are respectively formed by the right-angled waist surfaces of two right-angled trapezoidal prisms. The light source device 10 faces the second surface 22, and the wavelength conversion device 40 faces the first surface 21. The excitation light emitted by the light source device 10 enters the optical device 20 through the first surface 21 and enters the light splitting and combining unit 30, and the light splitting and combining unit 30 Reflect the received excitation light to the wavelength conversion device 40; the received laser light emitted by the wavelength device device 40 enters the optical device 20 through the first surface 21, and part of the received laser light is transmitted through the light splitting and combining unit 30 and exits from the third surface 23, The remaining part of the received laser light passes through the optical device 20 around the light splitting and combining unit 30 and exits from the third surface 23.

The light splitting and combining unit 30 is arranged at the junction of two right-angle trapezoidal prisms, and the light splitting and combining unit 30 is arranged obliquely with respect to the optical path of the excitation light emitted by the light source device 10. Specifically, the light source device 10 and the wavelength conversion device 40 are respectively disposed on the adjacent second surface 22 and the first surface 21 of the optical device 20, and the light exit surface of the light source device 10 and the wavelength conversion device 40 are perpendicular to each other, and the light source device 10 emits The laser light enters the optical device 20 perpendicularly from the second surface. The light splitting and combining unit 30 is inclined at 45° with respect to the optical path of the excitation light emitted by the light source device 10. After the excitation light is reflected by the light splitting and combining unit 30, it can be incident perpendicularly to the wavelength Switching device 40. In other embodiments, the light source device 10 and the wavelength conversion device 40 may also be respectively disposed on the other adjacent two sides of the optical device 20, which will not be listed here.

In this embodiment, the area of the orthographic projection of the light splitting and combining unit 30 on the first surface 21 is smaller than the area of the first surface 21. Therefore, the orthographic projection of the light splitting and combining unit 30 on the first surface 21 does not completely cover the first surface. 21. A part of the received laser light can pass through the optical device 20 around the light splitting and combining unit 30 and then exit from the third surface 23, so that the volume of the light splitting and combining unit 30 does not need to be too large, and does not need to cover the light emitted by the wavelength conversion device 40 In the case of all laser-received regions, the uniformity of the laser-received translation can also be maintained, which is beneficial to reducing the processing difficulty of the light splitting and combining unit 30 and the manufacturing cost of the light source system 100. In one embodiment, the area of the orthographic projection of the light splitting and combining unit 30 on the first surface 21 is located in the middle area of the first surface 21, which helps the light splitting and combining unit 30 and the optical device 20 to be arranged more reasonably.

In this embodiment, referring to FIG. 7, the light splitting and combining unit is an optical coating 51 formed on the inclined surface of at least one of the two right-angled isosceles trapezoidal prisms, and the optical coating 51 is used to reflect excitation light and transmit the received light. laser. In this way, the light splitting and combining unit 30 realizes the reflection of the excitation light and the transmission of the received laser light through the optical coating 51. In this embodiment, the optical coating 51 can reflect blue light and transmit red light, green light, and yellow light.

The optical coating 51 may have the coating characteristics of wavelength splitting and combining light, and the optical coating 51 may also have the coating characteristics of polarization splitting and combining light. When the optical coating 51 is the coating characteristic of wavelength splitting and combining light, as shown in Figure 8, the optical coating 51 can realize the reflection of short-wavelength light (or excitation light) and the transmission of long-wavelength light (or laser light), thereby achieving Combination of light of different wavelengths. When the optical coating 51 has the coating characteristics of polarization splitting and combining light, as shown in FIG. 9, the optical coating 51 can realize the reflection of S-polarized light and the transmission of P-polarized light, thereby realizing the combination of light of different polarizations.

When the wavelength conversion device 40 is excited by the excitation light, because the wavelength conversion device 40 has a certain reflectivity, all the excitation light cannot be absorbed, and the unconverted excitation light will be reflected back by the wavelength conversion device 40. When the excitation light is blue light, the unconverted excitation light reflected by the wavelength conversion device 40 can be recovered and directly used for blue light display. In this embodiment, the optical coating 51 has the characteristics of combining wavelength splitting and combining light and polarization splitting and combining light, as shown in FIG. 10, so that the optical coating 51 as a whole can achieve short-wavelength (λ ₁ ) excitation light The reflection and long-wavelength (λ ₂ ) of the laser light transmission. In addition, due to the characteristics of the coating, the cut-off wavelength of S-polarized light is longer than that of P-polarized light, and S-polarized light is more easily reflected than P-polarized light, so that the optical coating 51 can reflect short-wavelength light with _{a wavelength of λ 1 in the S polarization state.} (Excitation light), and transmits short-wavelength light (excitation light) with _{a wavelength of λ 1} in the P polarization state and long-wavelength light (laser light) with _{a wavelength of λ 2 in the S polarization state and P polarization state. Therefore, in this implementation} In an example, the light source device 10 may emit excitation light in the first polarization state, for example, blue laser light in the S polarization state with a wavelength of 455 nm. The optical coating 51 reflects the excitation light of the first polarization state and transmits the received laser light emitted by the wavelength conversion device 40. After the unconverted excitation light is reflected by the wavelength conversion device 40, the polarization state becomes disordered, which includes the excitation light of the first polarization state and the excitation light of the second polarization state, wherein the excitation light of the second polarization state can pass through The optical coating film 51 is emitted from the optical device 20 for blue light display, thereby improving the light utilization rate of the light source system 100 and increasing the brightness.

In the examples shown in FIGS. 8 to 10, the ordinate "T" in the line graph represents the transmittance (Transmittance), and the abscissa "λ" represents the wavelength (Wavelength).

Since the excitation light with higher energy density will accelerate the aging of the glue used to join the two right-angle trapezoidal prisms, the optical coating 51 can be arranged on the first inclined surface 31 of the right-angle isosceles trapezoidal prism close to the light source device 10, so that the optical coating 52 is closer to the light source device 10 than the glue, so that the excitation light emitted by the light source device 10 is directly reflected by the optical coating 52 to the wavelength conversion device 40, and the excitation light is no longer incident on the glue, thereby effectively preventing the excitation light from accelerating the aging of the glue and improving the light source The reliability and service life of the system 100.

The optical device 20 may include other types of films. For example, referring to FIG. 7, the optical device 20 includes an excitation light antireflection film 52, and the excitation light antireflection film 52 is disposed on the second surface 22 of the optical device 20. In this way, the excitation light antireflection film 52 can improve the emission of the light source device 10 The transmittance when the excitation light enters the optical device 20 from the second surface 22.

For example, the optical device 20 includes a white light anti-reflection film 53, the white light anti-reflection film 53 can be provided on the first surface 21, on the third surface 23, or on the first surface 21 and the third surface 23 at the same time. The white light antireflection film 53 can increase the transmittance of the laser light emitted by the wavelength conversion device 40 when it enters the optical device 20 from the first surface 21 and the transmittance when it exits from the third surface 23. In addition, the white light anti-reflection film 53 can also be arranged on the second inclined surface 32 of the right-angle isosceles trapezoidal prism away from the light source device 10. In this way, the white light anti-reflection film 53 can improve the transmission of the received laser light when passing through the second inclined surface 32. Rate. It should be noted that the white light anti-reflection film 53 may be provided on at least one of the first surface 21, the third surface 23, and the second inclined surface 32.

The light source system 100 further includes a collecting lens group 70. The collecting lens group 70 may be composed of multiple lenses. For example, the collecting lens group 70 may be composed of three or four lenses. In this embodiment, the collecting lens group includes three convex lenses. The wavelength conversion device 40 can receive the excitation light through the collection lens group 70, and the laser light emitted by the wavelength conversion device 40 and the excitation light reflected by the wavelength conversion device 40 can be collected, concentrated, collimated and incident on the optical device 20 through the collection lens group 70. . In this way, the collection of the excitation light and the collection of the received laser light can be achieved by setting a collection lens group 70.

In addition, after the received laser light is excited, the received laser light emitted by the wavelength conversion device 40 is similar to a Lambertian light source. The brightness of the received laser light in all directions is the same. The collection of the received laser light by the collection lens group 70 can obtain a better result. Great collection efficiency.

In the solution of recycling the unconverted excitation light in the above embodiment, the optical coating 51 only transmits the unconverted excitation light of the second polarization state, and the optical device 20 around the optical coating 51 makes the first polarization state and the second polarization state pass through. The unconverted excitation light in the two polarization states is transmitted through, so that the light brightness of the blue spot in the light path emitted by the optical device 20 is lower in the central area than in the outer peripheral area.

Referring to FIG. 11, in the solution of another embodiment, the light source system 100 further includes a supplementary light source 60, which faces the fourth surface 24 of the optical device 20 and is spaced from the optical device 20. The supplementary light source 60 is used to emit supplementary light. The supplementary light is light in the first polarization state and has the same color as the excitation light emitted by the light source device 10, that is, the supplementary light is blue light in the first polarization state. The supplementary light emitted by the supplementary light source 60 enters the light splitting and combining unit 30 through the fourth surface 24, and the supplementary light is reflected by the light splitting and combining unit 30 to the third surface 23 and exits through the third surface 23. In this embodiment, by setting the supplementary light source, the polarization state and color of the supplementary light and the laser light are the same, which can supplement the excitation light of the first polarization state polarized light lacking in the central area of the optical path emitted by the optical device 20, This makes the light intensity of the light spot after exiting the optical device 20 more uniform.

Referring to FIG. 11, in this embodiment, the light splitting and combining unit 30 further includes an optical coating 51 disposed on the second inclined surface 32 of the right-angled isosceles trapezoidal prism close to the supplementary light source 60, that is, two right-angled trapezoidal prisms An optical coating 51 is provided on the inclined surface of the optical coating 51, and the optical coating 51 can reflect the supplementary light and transmit the laser light and the excitation light of the second polarization state. Since the polarization states and colors of the supplementary light and the laser light are the same, the optical coating film 51 can reflect the excitation light and supplementary light of the first polarization state, and transmit the laser light and the excitation light of the second polarization state. By arranging the optical coating 51 on the second inclined surface 32, it supplements the excitation light of the first polarization state polarized light that is lacking in the central area of the optical path emitted by the optical device 20, and prevents the supplementary light from passing through the glue to prevent the glue from aging, Improve the reliability and service life of the light source system 100.

In the case where the light source system 100 includes a supplementary light source 60, the optical device 20 further includes a supplementary light antireflection film 55, and the supplementary light antireflection film 55 may be disposed on the fourth surface 24 of the optical device 20. In this way, the supplementary light antireflection film 55 The transmittance of the supplementary light emitted from the supplementary light source 60 when exiting the optical device 20 from the fourth surface 24 can be improved. The optical device 20 also includes a white light anti-reflection film 53, which can be arranged on the first surface 21 of the optical device 20, or on the third surface 23, or on the first surface 21 and the third surface at the same time 23. In this way, the white light antireflection film 53 can increase the transmittance of the laser light emitted by the wavelength conversion device 40 when it enters the optical device 20 from the first surface 21 and the transmittance when it exits the optical device 20 from the third surface 23.

Referring to FIG. 12, an embodiment of the present invention provides a projection device 200, and the projection device 200 includes the light source system 100 of any one of the foregoing embodiments.

Among them, the projection device 200 may be a cinema projector, an engineering projector, a micro projector, an education projector, a wall-mounted projector, a laser TV, and so on. The projection device 200 may further include a housing 301, and the light source system 100 is disposed in the housing 301. The housing 301 can protect the light source system 100 and prevent the light source system 100 from being directly impacted by the external environment. In the projection device 200 of the embodiment of the present invention, the volume of the optical device 20 can be reduced, thereby reducing the dilution of the optical expansion amount of the received laser light during the propagation process, which is beneficial to improving the brightness of the light source system 100.

The above embodiments are only used to illustrate the technical solutions of the present invention, not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, a person of ordinary skill in the art should understand that: The recorded technical solutions are modified, or some of the technical features are equivalently replaced; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the present invention Within the scope of protection.

Claims

A light source system, characterized in that it comprises:

Light source device for emitting excitation light;

A wavelength conversion device for converting the received excitation light into at least part of the received laser light;

Light splitting and light combining unit; and

Optical device, the light source device and the wavelength conversion device are respectively arranged on two adjacent sides of the optical device, the light splitting and combining unit is arranged inside the optical device; the excitation light enters the optical device And incident to the light splitting and combining unit, the light splitting and combining unit reflects the received excitation light to the wavelength conversion device; the received laser light emitted by the wavelength conversion device enters the optical device, and part of the received light The laser light is transmitted through the light splitting and combining unit to exit from the optical device, and the remaining part of the received laser light passes through the optical device around the light splitting and combining unit and exits from the optical device.
The light source system according to claim 1, wherein the light splitting and combining unit is arranged obliquely with respect to the optical path of the excitation light emitted by the light source device.
The light source system according to claim 1, wherein the optical device comprises a first surface, a second surface, and a third surface that are connected, and the first surface and the third surface are arranged relatively parallel, The wavelength conversion device faces the first surface, the light source device faces the second surface, and the received laser light is emitted from the third surface.
The light source system according to claim 3, wherein the area of the orthographic projection of the light splitting and combining unit on the first surface is smaller than the area of the first surface.
The light source system according to claim 4, wherein the area of the orthographic projection of the light splitting and combining unit on the first surface is located in the middle area of the first surface.
The light source system according to claim 3, wherein the optical device is a hollow cuboid prism, the light splitting and combining unit is a light splitting sheet, the light splitting sheet is arranged inside the optical device, and the light splitting The sheet reflects the excitation light and transmits the received laser light.
The light source system according to claim 3, wherein the optical device is a rectangular parallelepiped prism formed by combining two right-angled trapezoidal prisms, and the inclined surfaces of the two right-angled trapezoidal prisms are combined, and the light splitting and combining unit It is arranged at the joint of the two right-angle trapezoidal prisms.
7. The light source system according to claim 7, wherein the light splitting and combining unit is a light splitting sheet sandwiched between the two right-angle trapezoidal prisms, and the light splitting sheet reflects the excitation light and transmits the received laser light.
8. The light source system according to claim 8, wherein the light splitting and combining unit is an optical coating formed on the slope of at least one of the right-angled trapezoid prisms, and the optical coating reflects excitation light and transmits the received laser light.
The light source system according to any one of claims 6 to 9, wherein the distance between the first surface and the third surface is equal to the shortest edge length of the cuboid prism.
The light source system according to any one of claims 1 to 9, wherein the light source device emits excitation light in the first polarization state, and the light splitting and combining unit reflects the excitation light in the first polarization state and transmits the excitation light in the first polarization state. By the laser light and the excitation light of the second polarization state.
The light source system according to claim 11, wherein the light source system further comprises a supplementary light source, the supplementary light source is used to emit supplementary light of the first polarization state, and the supplementary light and the excitation light have the same color The supplementary light source is arranged on a side of the optical device away from the light source device, the supplementary light emitted by the supplementary light source enters the optical device and is incident on the light splitting and combining unit, the The supplementary light is reflected by the light splitting and combining unit and exits the optical device along the same optical path as the received laser light.
The light source system according to claim 12, wherein the optical device is a rectangular parallelepiped prism formed by combining two right-angled trapezoidal prisms, the slopes of the two right-angled trapezoidal prisms are combined, and the two right-angled trapezoid An optical coating is provided on the slope of the volume prism, and the optical coating reflects the excitation light in the first polarization state and the supplementary light, and transmits the received laser light and the excitation light in the second polarization state.
A projection device, characterized by comprising the light source system according to any one of claims 1 to 13.