CN113495412A

CN113495412A - Light source system and projection apparatus

Info

Publication number: CN113495412A
Application number: CN202010197130.4A
Authority: CN
Inventors: 陈晨; 胡飞; 余新; 李屹
Original assignee: Appotronics Corp Ltd
Current assignee: Shenzhen Appotronics Corp Ltd
Priority date: 2020-03-19
Filing date: 2020-03-19
Publication date: 2021-10-12
Also published as: WO2021184924A1

Abstract

The invention provides a light source system and projection equipment, wherein the light source system comprises a light source device, a wavelength conversion device, an optical device and a light splitting and combining unit; the light source device is used for emitting exciting light, the wavelength conversion device is used for converting the received exciting light into received laser at least partially, the light source device and the wavelength conversion device are respectively arranged on two adjacent side surfaces of the optical device, the light splitting and combining unit is arranged in the optical device, the exciting light enters the optical device and enters the light splitting and combining unit, the light splitting and combining unit reflects the received exciting light to the wavelength conversion device, the received laser emitted by the wavelength conversion device enters the optical device, part of the excited light is emitted from the optical device through the light splitting and combining unit in a transmission mode, and the rest of the received laser penetrates through the optical device around the light splitting and combining unit and is emitted from the optical device. The light source system provided by the invention is beneficial to improving the brightness.

Description

Light source system and projection apparatus

Technical Field

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

Background

The existing laser fluorescent light source is widely applied to various projection equipment by virtue of the advantages of long service life, low cost and high brightness, and has a very good display effect. The important point in the laser fluorescence technology is the fluorescence excitation scheme and the fluorescence and laser light combination scheme, and the development of the fluorescence excitation scheme and the fluorescence and laser light combination scheme which are more efficient and compact has important significance for the development of the laser fluorescence technology.

In the fluorescence excitation and collection scheme used in the prior art, the dichroic filter is generally used to reflect the excitation light with short wavelength and transmit the fluorescence with long wavelength to realize the light splitting and light combining of the laser light and the fluorescence. In order to ensure the translational consistency of the fluorescent light beam and avoid the scattering of light rays by the edges of the dichroic filters, the dichroic filters are required to cover all fluorescent regions, so that the area of the dichroic filters is required to be large, the propagation distance of the fluorescent light after passing through the collecting lens group is too long, the optical expansion of the fluorescent light is diluted, and the improvement of the brightness of the laser fluorescent light source is not facilitated.

Disclosure of Invention

The present invention provides a light source system and a projection apparatus to solve the above problems.

The embodiment of the invention achieves the aim through the following technical scheme.

In a first aspect, an embodiment of the present invention provides a light source system, where 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 for emitting exciting light, and the wavelength conversion device is used for converting the received exciting light into stimulated light at least partially; the light source device and the wavelength conversion device are respectively arranged on two adjacent side surfaces of the optical device, and the light splitting and combining unit is arranged in the optical device; exciting light enters the optical device and enters the light splitting and combining unit, the light splitting and combining unit reflects the received exciting light to the wavelength conversion device, the excited light emitted by the wavelength conversion device enters the optical device, part of the excited light is emitted from the optical device through the transmission of the light splitting and combining unit, and the rest of the excited light passes through the optical device around the light splitting and combining unit and is emitted from the optical device.

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

In one embodiment, the optical device comprises a first surface, a second surface and a third surface which are connected, wherein the first surface and the third surface are arranged in parallel relatively, the wavelength conversion device faces the first surface, the light source device faces the second surface, and the excited light exits 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 orthographic projection area 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 rectangular 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 excited light.

In one embodiment, the optical device is a rectangular prism formed by splicing two right-angle trapezoidal prism, the inclined surfaces of the two right-angle trapezoidal prism are spliced, and the light splitting and combining unit is arranged at the splicing position of the two right-angle trapezoidal prism.

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

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

In one embodiment, the first surface is spaced from the third surface by a distance equal to the shortest edge length of the rectangular prism.

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

In one embodiment, the light source system further comprises a supplementary light source for emitting supplementary light of a first polarization state, the supplementary light and the excitation light being of the same color; the supplementary light source is arranged on one side surface of the optical device, which is deviated from the light source device, the supplementary light emitted by the supplementary light source enters the optical device and enters the light splitting and combining unit, and the supplementary light is reflected by the light splitting and combining unit and is emitted from the optical device along the same light path as the received laser.

In one embodiment, the optical device is a rectangular prism formed by splicing two right-angle trapezoidal prism, the inclined surfaces of the two right-angle trapezoidal prism are spliced, optical coating films are arranged on the inclined surfaces of the two right-angle trapezoidal prism, the optical coating films reflect exciting light and supplementary light in a first polarization state and transmit the exciting light and the exciting light in a second polarization state.

In a second aspect, an embodiment of the present invention provides a projection apparatus, where the projection apparatus includes the light source system of any one of the above embodiments.

In the light source system and the projection equipment provided by the invention, part of the excited light is transmitted by the light splitting and combining unit and then is emitted from the third surface, and the rest part of the excited light is emitted from the third surface after passing through the optical devices around the light splitting and combining unit, so that the volume of the optical devices can be reduced, the dilution of the optical expansion of the excited light in the transmission process is reduced, and the brightness of the light source system is favorably improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

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

Fig. 2 is a schematic structural diagram of an optical device and a 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 the estimation of the shift amount of the dichroic sheet provided by the prior art.

Fig. 5 is a schematic diagram of the estimation of etendue of a dichroic sheet provided by the prior art.

Fig. 6 is a schematic diagram showing an estimation of the etendue of the light source system of fig. 1.

Fig. 7 is a schematic structural diagram of a light source system according to another embodiment of the present invention.

Fig. 8 is a schematic view of characteristics of an optical coating film of the light source system of fig. 7.

Fig. 9 is a schematic view showing characteristics of another optical coating film of the light source system of fig. 7.

Fig. 10 is a schematic view of characteristics of still another optical coating of the light source system of fig. 7.

Fig. 11 is a schematic structural diagram of a light source system according to another embodiment of the present invention.

Fig. 12 is a schematic structural diagram of a projection apparatus according to an embodiment of the present invention.

Detailed Description

In order to make the technical solutions of the present invention better understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1, an embodiment of the invention provides a light source system 100, where 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 for emitting excitation light, and the wavelength conversion device 40 is used for at least partially converting the received excitation light into the stimulated light.

The light source device 10 and the wavelength conversion device 40 are respectively disposed on two adjacent side surfaces of the optical device 20, and the light splitting and combining unit 30 is disposed inside the optical device 20. The excitation light emitted by the light source device 10 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 device 40, and the wavelength conversion device 40 at least partially converts the received excitation light into the received laser light; the received laser light emitted from the wavelength conversion device 40 enters the optical device 20, part of the excited light is transmitted through the light splitting and combining unit 30 and is 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 combining unit 30 and is emitted from the optical device 20.

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 may be a Laser Diode (Laser Diode) Light source or a Light Emitting Diode (Light Emitting Diode) Light source to emit the excitation Light. The excitation light emitted by the light source device 10 may be blue light, violet light, red light, green light, ultraviolet light, or other types of light, which are not listed here. In the present 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 may be one or more than one. The plurality of blue semiconductor diodes may form a semiconductor diode array.

In one embodiment, the blue semiconductor laser diode is a gan-based blue laser, which has low light emitting efficiency and manufacturing cost, overcomes the limitations of poor thermal stability of red laser material and low efficiency and short life of green laser, and can implement red-green spectrum with the wavelength conversion device 40.

The wavelength conversion device 40 is located on the optical path of the excitation light reflected by the light splitting and combining unit 30, and is respectively disposed on two adjacent side surfaces 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 at least part of the received excitation light into stimulated light, wherein the excitation light is a relative concept to the stimulated light, and the excitation light represents light capable of exciting the wavelength conversion material layer such that the wavelength conversion material generates light of different wavelengths. The excited light means light generated by the wavelength conversion material layer excited by the excitation light. For example, the blue light excites the yellow light conversion material layer to generate yellow light, and the blue light is the excitation light and the yellow light is the stimulated light. The yellow light excites the red conversion material layer to generate red light, and the yellow light is excited light and the red light is excited light. The blue light excites the green light conversion material layer to generate green light, and the blue light is exciting light and the green light is stimulated light.

The wavelength conversion material may include a phosphorescent material, such as a phosphor, or may include a nanomaterial, such as a quantum dot, or may include a fluorescent material, not to be enumerated herein. In one embodiment, the wavelength conversion material includes a fluorescent material, and the stimulated light emitted by the wavelength conversion device 40 is fluorescent light, so that the stimulated light is not affected by speckle due to incoherent light, and by exciting the fluorescent material with blue light to generate green fluorescent light and red fluorescent light, the speckle problem of human vision caused by coherence of the excitation light emitted by the light source device 10 can be avoided.

The wavelength conversion device 40 is provided with a heat sink (not shown), such as heat sink fins, for heat dissipation. The heat sink may be disposed on a surface of the wavelength conversion device 40 opposite the light emitting surface. By using the heat dissipation device to conduct the excess heat to the surrounding environment, the temperature of the wavelength conversion material layer is not raised excessively to affect the light emitting 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 received laser light emitted by the wavelength device 40, and the optical device 20 is respectively arranged at intervals with the light source device 10 and the wavelength conversion device 40. In this embodiment, the optical device 20 is a prism, and the optical device 20 can transmit the excitation light and the received laser light. The optical device 20 comprises a first surface 21, a second surface 22, a third surface 23 and a fourth surface 24 which are connected, wherein the first surface 21 and the third surface 23 are arranged in parallel relatively, and the second surface 22 and the fourth surface 24 are arranged in parallel relatively; the light source device 10 faces the second surface 22, 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 is incident to the light splitting and combining unit 30, and the light splitting and combining unit 30 reflects the received excitation light to the wavelength conversion device 40; the received laser light emitted from the wavelength device 40 enters the optical device 20 through the first surface 21, part of the excited light is transmitted by the light splitting and combining unit 30 and is emitted from the third surface 23, and the rest of the received laser light passes through the optical device 20 around the light splitting and combining unit 30 and is emitted from the third surface 23.

In one embodiment, as shown in fig. 2, the optical device 20 may be a rectangular prism integrally formed and hollow inside. In other embodiments, as shown in fig. 3, the optical device 20 may be a rectangular prism formed by splicing two rectangular trapezoid prisms. The first surface 21 and the third surface 23 of the optical device 20 may have a distance equal to the shortest edge length of the rectangular prism. In this way, the received laser light is transmitted through the rectangular prism from the direction of the shortest edge length of the rectangular prism, and the propagation distance of the received laser light in the optical device 20 can be reduced, which is advantageous for reducing the dilution of the etendue 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, green light, and yellow light. In the case that the optical device 20 is a hollow rectangular prism, the light splitting and combining unit 30 may be a light splitter, and the light splitter is disposed in the hollow cavity of the optical device 20. In the case that the optical device 20 is a rectangular prism formed by splicing two right-angle trapezoidal prisms, the beam splitting and combining unit 30 may be a beam splitter, and the beam splitter is clamped at the splicing position of the two right-angle trapezoidal prisms; the light splitting and combining unit 30 may also be an optical coating 51, and the optical coating 51 may be formed on an inclined plane of one of the right-angle trapezoidal prisms, or may be formed on inclined planes of two right-angle trapezoidal prisms.

The optical device 20 and the light splitting and combining unit 30 are matched in the above manner, so that a part of the excited light is emitted from the third surface 23 after being transmitted by the light splitting and combining unit 30, and the rest of the received laser light is emitted from the third surface 23 after passing through the optical device 20 around the light splitting and combining unit 30, so that the light splitting and combining unit 30 can also keep the translation consistency of the received laser light after transmitting the optical device 20 under the condition that the light splitting and combining unit 30 does not need to cover all the received laser light regions emitted by the wavelength conversion device 40, and can also reduce the dilution of the optical expansion (Etendue) of the light source system 100, keep the capacity of the light source system 100 for transmitting light energy, and be beneficial to improving the brightness of the light source system 100.

Etendue is notImaging optics are used to describe the geometrical properties of a light beam having an aperture angle and a cross-sectional area, the Etendue being the integral of the area traversed by the beam and the solid angle occupied by the beam, i.e. Etendue ≡ n²Integral whole number cos theta dAd omega. Where θ is the angle between the normal of the area infinitesimal dA and the central axis of the solid angle infinitesimal d Ω. In an ideal optical system, which does not consider energy loss caused by scattering and absorption, the etendue of a light beam after passing through the ideal optical system is kept conservative. Etendue measures the change between the source area and the solid angle spread of a beam as it passes through an optical system. The larger the beam angle or the larger the beam source area, the larger the resulting etendue, the lower the ability of the optical system to transmit light energy, and the less favorable it is for improving the brightness of the optical system.

In the prior art, when light enters the dichroic plate 200 with refractive index n and thickness t at an oblique angle by using the dichroic plate 200 (fig. 4), a certain translation occurs in the incident plane, as shown in fig. 4. Assuming the angle of incidence of the light ray is θ, the amount of translation of the light ray is

Further simplification obtains:

as can be seen from the above formula, when n → 1, the translation amount Δ y (0; θ) → 0. Whereas for typical glass the index of refraction is about 1.5, so that an obliquely incident ray will always have some amount of translation after passing through the dichroic plate 200.

In the prior art, in order to ensure the consistency of the translation of the received laser light, and avoid the displacement of part of the received laser light and the non-displacement of part of the received laser light when the obliquely incident received laser light passes through the dichroic sheet 200 and the scattering of the received laser light caused by the edge of the dichroic sheet 200, the area of the dichroic sheet 200 needs to be enlarged to cover all the received laser light regions emitted by the wavelength conversion device 40, but the optical expansion of the light source system 100 is easily increased, which is not beneficial to improving the brightness of the light source system 100.

The present invention adopts the schematic diagrams of fig. 5 and fig. 6 to estimate and compare the etendue obtained by the solutions of the prior art and the present embodiment, wherein the prior art adopts the dichroic sheet 200 (fig. 5), and the present embodiment adopts the form that the optical device 20 is matched with the light splitting and combining unit 30 (fig. 6).

Referring to FIG. 5, assume that the spot size of the light emitted from the wavelength conversion device 40 at position A is D₀The exit angle of the light spot is theta₀The divergence angle of the emitted light is theta₁Size D of the spot at position B after light transmission through dichroic sheet 200₁The distance between the position A and the position B is t₁The dichroic sheet 200 is inclined at 45 ° to the optical path of the incident light, t₁＝D₀+t₁tan(θ₁)，

Referring to FIG. 6, assume that the spot size of the light emitted from the wavelength conversion device 40 at position A is D₀The exit angle of the light spot is theta₀The divergence angle of the emitted light is theta₂The size D of the light spot at the position B after the light transmission optical device 20 and the light splitting and combining unit 30₂The distance between the position A and the position B is t₂The refractive index of the optical device 20 is n, and the light splitting and combining unit 30 is inclined at 45 ° to the optical path of the incident light. Then D is₂＝D₀+2t2tan(θ₂) Suppose that

Then D is₂＝D₀[1+tan(θ₂)]In which sin (theta)₁)＝nsin(θ₂)。

In general, the divergence angle of the light upon exiting is not so large that θ₁Can be approximated as the angle is smaller, then₁≈sin(θ₁)≈tan(θ₁) Thus:

subjecting the above D to₁And D₂A comparison is made to estimate the extent of etendue dilution, e.g., D may be₁And D₂The magnitude of the two values is compared by making a difference or a quotient.

If D is₁And D₂By making a difference comparison, then

In general, n ≈ 1.5 is substituted into the calculation

It can be seen that when light exits and a certain divergence angle exists, i.e., the divergence angle θ₁In the case of > 0, D₁-D₂If the condition is the same, it can be shown that the area of the light spot formed by using the dichroic sheet 200 is larger than that of the optical device 20 and the light splitting and combining unit 30 of the embodiment of the present invention, which is not favorable for reducing the etendue of the light source system 100 and is not favorable for improving the brightness of the light source system 100.

If D is₁And D₂By way of quotient comparison, then

In general, θ₁Is approximately equal to 3 degrees, and n is approximately equal to 1.5, and the substitution calculation can obtain

It can be obtained that the etendue of the solution using the dichroic plate 200 in the prior art is increased by 14% compared with the solution in which the optical device 20 and the light splitting and combining unit 30 are matched with each other under the same condition.

Therefore, it can be seen from the above two comparison manners that the volume of the optical device 20 can be reduced, so that the dilution of the etendue of the received laser light in the propagation process is reduced, and the brightness of the light source system 100 is improved.

Referring to fig. 1, in an embodiment, a 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 prism formed by splicing two right-angle trapezoidal body prisms, the two right-angle trapezoidal body prisms are respectively provided with a first inclined surface 31 and a second inclined surface 32, the first inclined surface 31 and the second inclined surface 32 are spliced through optical glue, namely, the first inclined surface 31 and the second inclined surface 32 of the two right-angle trapezoidal body prisms are opposite, one of the right-angle trapezoidal body prisms is turned upside down, the upper bottom surface and the lower bottom surface of the one right-angle trapezoidal body prism are respectively flush with the lower bottom surface and the upper bottom surface of the other right-angle trapezoidal body prism, and therefore the first inclined surface 31 and the second inclined surface 32 of the two right-angle trapezoidal body prisms are spliced into the rectangular prism through the optical glue. Thus, the two right-angle trapezoidal prisms can be prevented from being separated from each other when the light source system 100 is collided by the outside, which is beneficial to improving the stability of the optical device 20 and ensuring 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 connected to each other, and the first surface 21 and the third surface 23 are disposed in parallel with each other, and the second surface 22 and the fourth surface 24 are disposed in parallel with each other; the first surface 21 is formed by connecting the bottom surface of one of the right-angle trapezoidal prism and the top surface of the other right-angle trapezoidal prism, the third surface 23 is formed by connecting the top surface of one of the right-angle trapezoidal prism and the bottom surface of the other right-angle trapezoidal prism, and the second surface 22 and the fourth surface 24 are respectively formed by the right-angle waist surfaces of the two right-angle trapezoidal prisms. The light source device 10 faces the second surface 22, 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 is incident to the light splitting and combining unit 30, and the light splitting and combining unit 30 reflects the received excitation light to the wavelength conversion device 40; the received laser light emitted from the wavelength device 40 enters the optical device 20 through the first surface 21, part of the excited light is transmitted by the light splitting and combining unit 30 and is emitted from the third surface 23, and the rest of the received laser light passes through the optical device 20 around the light splitting and combining unit 30 and is emitted from the third surface 23.

The light splitting and combining unit 30 is disposed at the joint of the two right-angle trapezoidal prisms, and the light splitting and combining unit 30 is disposed in an inclined manner with respect to the optical path of the excitation light emitted from 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, the light emitting surface of the light source device 10 is perpendicular to the wavelength conversion device 40, the laser light emitted from the light source device 10 enters the optical device 20 from the second surface, the light splitting and combining unit 30 is inclined at 45 ° relative to the optical path of the excitation light emitted from the light source device 10, and the excitation light can enter the wavelength conversion device 40 perpendicularly after being reflected by the light splitting and combining unit 30. In other embodiments, the light source device 10 and the wavelength conversion device 40 may be disposed on other adjacent two sides of the optical device 20, which is not illustrated herein.

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, so that the orthographic projection of the light splitting and combining unit 30 on the first surface 21 does not completely cover the first surface 21, and a part of the received laser light can be emitted from the third surface 23 after passing through the optical device 20 around the light splitting and combining unit 30, so that the volume of the light splitting and combining unit 30 does not need to be too large, and the consistency of the translation of the received laser light can be maintained even in the case that all the regions of the received laser light emitted by the wavelength conversion device 40 do not need to be covered, which is beneficial to reducing the processing difficulty of the light splitting and the manufacturing cost of the light source system 100. In one embodiment, the orthographic projection area 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 to reasonably arrange the positions of the light splitting and combining unit 30 and the optical device 20.

In the present embodiment, referring to fig. 7, the light splitting and combining unit is an optical coating 51 formed on an inclined surface of at least one right-angled trapezoid prism of the two right-angled isosceles trapezoid prisms, and the optical coating 51 is used for reflecting the excitation light and transmitting the receiving laser light. In this way, the light splitting and combining unit 30 reflects the excitation light and transmits the received laser light through the optical coating 51. In this embodiment, the optical coating film 51 can reflect blue light and transmit red light, green light, and yellow light.

The optical coating 51 may have a coating property of wavelength division and combination, and the optical coating 51 may have a coating property of polarization division and combination. When the optical coating 51 has the coating characteristics of wavelength-splitting and light-combining, as shown in fig. 8, the optical coating 51 can reflect short-wavelength light (or excitation light) and transmit long-wavelength light (or received laser light), thereby achieving light-combining of different wavelengths. When the optical coating 51 has the coating property of polarization splitting and light combining, as shown in fig. 9, the optical coating 51 can reflect S-polarized light and transmit P-polarized light, thereby realizing light combining of different polarized lights.

When the excitation light excites the wavelength conversion device 40, since the wavelength conversion device 40 has a certain reflectance, the excitation light is not completely absorbed, and the unconverted excitation light is reflected by the wavelength conversion device 40. When the excitation light is blue light, unconverted excitation light reflected back by the wavelength conversion device 40 can be recovered and directly used for blue light display. In the present embodiment, the optical coating 51 has the coating property of combining the wavelength-splitting light beam and the polarization-splitting light beam, as shown in fig. 10, so that the optical coating 51 can be applied to a short wavelength (λ) as a whole₁) Reflection of excitation light and long wavelength (λ)₂) Is transmitted by the laser light. In addition, since the cut-off wavelength of the S-polarized light is longer than that of the P-polarized light due to the coating property, the S-polarized light is more easily reflected than the P-polarized light, so that the optical coating 51 can reflect the wavelength λ of the S-polarized state₁And transmits the wavelength of the P polarization state as λ₁And a wavelength of transmitting the S-polarization state and the P-polarization state is lambda₂Thus, in the present embodiment, the light source device 10 may emit excitation light of a first polarization state, for example, blue laser light of 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 from the wavelength conversion device 40. The unconverted excitation light, reflected by the wavelength conversion device 40 and having a polarization state that becomes disordered, comprises the excitation light of the first polarization state and the excitation light of the second polarization stateThe excitation light in the second polarization state can penetrate through the optical coating 51 and exit from the optical device 20 for blue light display, so that the light utilization rate of the light source system 100 is improved, and the brightness is improved.

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

Because the ageing of the glue of two right angle trapezoidal prism of amalgamation can be accelerated to the exciting light that energy density is higher, therefore can set up optics coating film 51 on the first inclined plane 31 of the right angle isosceles trapezoid prism that is close to light source device 10, make optics coating film 52 be closer to light source device 10 relatively glue, thereby the exciting light of light source device 10 transmission directly reflects to wavelength conversion device 40 through optics coating film 52, the exciting light no longer incides to glue, thereby can effectively avoid the ageing of exciting light acceleration glue, improve light source system 100's reliability and life.

The optical device 20 may include other types of films. For example, referring to fig. 7, the optical device 20 includes an excitation light reflection reducing film 52, and the excitation light reflection reducing film 52 is disposed on the second surface 22 of the optical device 20, so that the excitation light reflection reducing film 52 can improve the transmittance of the excitation light emitted from the light source device 10 when the excitation light enters the optical device 20 from the second surface 22.

For example, the optical device 20 includes a white light antireflection film 53, and the white light antireflection film 53 may be disposed on the first surface 21, the third surface 23, or both the first surface 21 and the third surface 23, so that the white light antireflection film 53 can improve the transmittance of the laser light emitted by the wavelength conversion device 40 when the laser light enters the optical device 20 from the first surface 21 and the transmittance of the laser light when the laser light exits from the third surface 23. In addition, the white light antireflection film 53 may also be disposed on the second inclined plane 32 of the right isosceles trapezoid prism away from the light source device 10, so that the white light antireflection film 53 can improve the transmittance of the received laser light when the received laser light passes through the second inclined plane 32. It should be noted that the white light antireflection film 53 may be disposed 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, and the collecting lens group 70 may be composed of a plurality of 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 may receive the excitation light through the collection lens group 70, and the excited light emitted by the wavelength conversion device 40 and the excitation light reflected by the wavelength conversion device 40 may be collected, collimated and incident to the optical device 20 through the collection lens group 70. Thus, the collection of the excitation light and the collection of the stimulated light can be realized by arranging a collection lens group 70.

In addition, after the stimulated light is excited, the stimulated light emitted by the wavelength conversion device 40 is approximately Lambertian, the brightness of the stimulated light (Lambertian Source) in all directions is the same, and the stimulated light is collected by the collection lens group 70, so that a large collection efficiency can be obtained.

In the scheme of recovering 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 devices 20 around the optical coating 51 transmit the unconverted excitation light of the first polarization state and the unconverted excitation light of the second polarization state, so that the brightness of the blue spot in the light path emitted by the optical devices 20 is lower in the central region than in the peripheral region.

Referring to fig. 11, in another embodiment, the light source system 100 further includes a supplemental light source 60, and the supplemental light source 60 faces the fourth surface 24 of the optical device 20 and is spaced apart from the optical device 20. The supplemental light source 60 is used for emitting supplemental light, which 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 supplemental light is blue light in the first polarization state. The supplementary light emitted by the supplementary light source 60 is incident to the light splitting and combining unit 30 through the fourth surface 24, and the supplementary light is reflected to the third surface 23 through the light splitting and combining unit 30 and is emitted through the third surface 23. In this embodiment, by providing the supplementary light source, the polarization state and the color of the supplementary light and the laser light are the same, and the excitation light of the first polarization state polarized light that is absent in the central region in the light path emitted from the optical device 20 can be supplemented, so that the light intensity of the light spot emitted from the optical device 20 is more uniform.

Referring to fig. 11, in the present embodiment, the light splitting and combining unit 30 further includes an optical coating 51 disposed on the second inclined plane 32 of the right-angled isosceles trapezoid prism close to the supplementary light source 60, that is, the optical coating 51 is disposed on the inclined planes of both right-angled trapezoid prisms, and the optical coating 51 can reflect the supplementary light and transmit the excited light and the excitation light of the second polarization state. Since the polarization state and the color of the complementary light and the laser light are the same, the optical coating film 51 can reflect the excitation light of the first polarization state and the complementary light, and transmit the excitation light of the excited light and the excitation light of the second polarization state. By arranging the optical coating 51 on the second inclined plane 32, the exciting light of the first polarization state polarized light which is lacked in the central area of the light path emitted by the optical device 20 is supplemented, and the supplemented light does not pass through the glue, so that the aging of the glue is prevented, and the reliability and the service life of the light source system 100 are improved.

In the case where the light source system 100 includes the supplemental light source 60, the optical device 20 further includes a supplemental light antireflection film 55, and the supplemental light antireflection film 55 may be disposed on the fourth surface 24 of the optical device 20, so that the supplemental light antireflection film 55 can improve the transmittance of the supplemental light emitted by the supplemental light source 60 when the supplemental light exits the optical device 20 from the fourth surface 24. The optical device 20 further includes a white light antireflection film 53, where the white light antireflection film 53 may be disposed on the first surface 21, the third surface 23, or both the first surface 21 and the third surface 23 of the optical device 20, and thus, the white light antireflection film 53 can improve the transmittance of the laser light emitted by the wavelength conversion device 40 when the laser light enters the optical device 20 from the first surface 21 and the transmittance of the laser light when the laser light exits the optical device 20 from the third surface 23.

Referring to fig. 12, an embodiment of the invention provides a projection apparatus 200, where the projection apparatus 200 includes the light source system 100 according to any of the embodiments.

The projection device 200 may be a cinema projector, an engineering projector, a micro projector, an educational projector, a wall-splicing projector, a laser television, and the like. 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 from the external environment. In the projection apparatus 200 according to the embodiment of the present invention, the volume of the optical device 20 can be reduced, so that the dilution of the etendue of the received laser light during the propagation process is reduced, which is beneficial to improving the brightness of the light source system 100.

The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present invention, and are intended to be included within the scope of the present invention.

Claims

1. A light source system, comprising:

a light source device for emitting excitation light;

wavelength conversion means for converting the received excitation light at least partially into stimulated light;

a light splitting and combining unit; and

the light source device and the wavelength conversion device are respectively arranged on two adjacent side surfaces of the optical device, and the light splitting and combining unit is arranged in the optical device; the exciting light enters the optical device and enters the light splitting and combining unit, and the light splitting and combining unit reflects the received exciting light to the wavelength conversion device; the stimulated light emitted by the wavelength conversion device enters the optical device, part of the stimulated light is emitted from the optical device through the transmission of the light splitting and combining unit, and the rest part of the stimulated light passes through the optical device around the light splitting and combining unit and is emitted from the optical device.

2. The light source system according to claim 1, wherein the light splitting and combining unit is disposed obliquely with respect to a light path of the excitation light emitted from the light source device.

3. The light source system according to claim 1, wherein the optical device comprises a first surface, a second surface and a third surface connected to each other, the first surface and the third surface are disposed in parallel, the wavelength conversion device faces the first surface, the light source device faces the second surface, and the excited light exits from the third surface.

4. The light source system according to claim 3, wherein an area of an orthographic projection of the light splitting and combining unit on the first surface is smaller than an area of the first surface.

5. The light source system according to claim 4, wherein an orthographic projection area of the light splitting and combining unit on the first surface is located in a middle area of the first surface.

6. The light source system according to claim 3, wherein the optical device is a hollow rectangular prism, the light splitting and combining unit is a beam splitter disposed inside the optical device, and the beam splitter reflects the excitation light and transmits the received laser light.

7. The light source system according to claim 3, wherein the optical device is a rectangular prism formed by splicing two right-angle trapezoidal prism bodies, the inclined surfaces of the two right-angle trapezoidal prism bodies are spliced, and the light splitting and combining unit is disposed at the splicing position of the two right-angle trapezoidal prism bodies.

8. 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 stimulated light.

9. The light source system of claim 8, wherein the beam splitting and combining unit is an optical coating formed on an inclined surface of at least one of the right-angle trapezoidal prisms, and the optical coating reflects the excitation light and transmits the stimulated light.

10. The light source system according to any one of claims 6 to 9, wherein the first surface is spaced from the third surface by a distance equal to the shortest edge length of the rectangular prism.

11. The light source system according to any one of claims 1 to 9, wherein the light source device emits the excitation light of the first polarization state, and the light splitting and combining unit reflects the excitation light of the first polarization state and transmits the excitation light of the second polarization state.

12. The light source system of claim 11, further comprising a supplemental light source for emitting supplemental light of a first polarization state, the supplemental light and the excitation light being of the same color; the supplementary light source is arranged on one side surface of the optical device, which is deviated from the light source device, the supplementary light emitted by the supplementary light source enters the optical device and enters the light splitting and combining unit, and the supplementary light is reflected by the light splitting and combining unit and is emitted from the optical device along the same light path as the received laser.

13. The light source system of claim 12, wherein the optical device is a rectangular prism formed by splicing two right-angle trapezoidal prisms, the inclined surfaces of the two right-angle trapezoidal prisms are spliced, and each of the inclined surfaces of the two right-angle trapezoidal prisms is provided with an optical coating, and the optical coating reflects the excitation light and the supplementary light in the first polarization state and transmits the excitation light and the excitation light in the second polarization state.

14. A projection device comprising a light source system according to any one of claims 1 to 13.