CN217846875U - Projection light source and projection apparatus - Google Patents

Abstract

The application discloses projection light source and projection equipment belongs to the photoelectric technology field. The projection light source comprises a laser, a converging lens, a light combining lens, a light homogenizing part, a collimating lens and a fluorescent wheel which are sequentially arranged; the light-combining mirror comprises a transmission area and a reflection area surrounding the transmission area, and the light-homogenizing part is positioned in the central area of the surface of the collimating mirror close to the light-combining mirror; the laser emits laser to the converging mirror, the converging mirror converges the laser to the transmission area of the light combining mirror, the transmission area transmits the received laser to the homogenizing part, the homogenizing part homogenizes the laser, and the homogenized laser is emitted to the fluorescent wheel through the collimating mirror; the fluorescence wheel comprises a first area and a second area, the first area reflects the received laser back to the collimating mirror, and the second area emits fluorescence to the collimating mirror under the excitation of the received laser; the collimating lens also collimates the light received from the fluorescent wheel and then emits the light to the light-combining lens, and a reflecting area in the light-combining lens reflects the received light. The light source device solves the problem that the light emitting efficiency of a projection light source is low. The application is used for light emission.

Description

Projection light source and projection apparatus

Technical Field

The application relates to the field of photoelectric technology, in particular to a projection light source and projection equipment.

Background

With the development of the electro-optical technology, the requirements for the image display effect of the projection device are higher and higher. The image display effect of the projection device is related to the luminous efficiency of the projection light source in the projection device, so the requirement for the luminous efficiency of the projection light source is also high.

In the related art, a projection light source in a projection apparatus includes a laser and a fluorescent wheel, and laser light emitted by the laser excites the fluorescent wheel to emit fluorescent light having a color different from that of the laser light, so that the projection light source can provide the laser light and the fluorescent light having different colors. A projection screen may then be formed based on the laser light and the fluorescent light emitted by the projection light source.

However, in the related art, the excitation efficiency of the fluorescent light on the fluorescent wheel is low, and thus the luminous efficiency of the projection light source is low.

SUMMERY OF THE UTILITY MODEL

The application provides a projection light source and projection equipment, can solve the lower problem of luminous efficacy of projection light source. The technical scheme is as follows:

in one aspect, a projection light source is provided, the projection light source comprising: the laser, the converging lens, the light combining lens, the light homogenizing part, the collimating lens and the fluorescent wheel are sequentially arranged; the light-combining mirror comprises a transmission area and a reflection area surrounding the transmission area, and the uniform light part is positioned in the central area of the surface of the collimating mirror close to the light-combining mirror;

the laser device is used for emitting laser to the converging mirror, the converging mirror is used for converging the laser to the transmission area of the light converging mirror, the transmission area is used for transmitting the received laser to the light homogenizing part, the light homogenizing part is used for homogenizing the received laser, and the homogenized laser is emitted to the fluorescent wheel through the collimating mirror;

the fluorescent wheel comprises a first area and a second area, the first area is used for reflecting the received laser light to the collimating mirror, and the second area is used for emitting fluorescent light to the collimating mirror under the excitation of the received laser light; the collimating mirror is also used for collimating the light received from the fluorescent wheel and then transmitting the light to the light-combining mirror, and the reflecting area in the light-combining mirror is used for reflecting the received light.

In another aspect, a projection apparatus is provided, the projection apparatus comprising: the projection light source, the light valve and the lens;

the projection light source is used for emitting laser to the light valve, the light valve is used for modulating the incident laser and then emitting the modulated laser to the lens, and the lens is used for projecting the incident laser to form a projection picture.

The beneficial effect that technical scheme that this application provided brought includes at least:

in the projection light source provided by the application, the central area of the surface close to the light-combining mirror in the collimating mirror is provided with the light-homogenizing part, and laser emitted by the laser can shoot to the light-homogenizing part through the transmission areas of the converging mirror and the light-combining mirror, and then is homogenized and then is shot to the fluorescent wheel through the collimating mirror. The dodging part on the surface of the collimating lens can enable the collimating lens not to converge the incident laser, so that the laser which is emitted to the fluorescent wheel can form a light spot with a certain area on the fluorescent wheel, the laser power density on the second area of the fluorescent wheel is small, and the fluorescence excitation efficiency of the second area is high. Therefore, the efficiency of the projection light source for emitting fluorescence is high, and the overall luminous efficiency of the projection light source is high.

And for the laser and the fluorescence emitted by the fluorescence wheel, the collimating lens can still collimate the laser and the fluorescence and then emits the laser and the fluorescence to the light-combining lens. And the laser emitted by the laser is emitted to the fluorescent wheel through the light homogenizing part positioned in the central area of the collimating mirror, and the laser can be emitted through the optical axis of the collimating mirror after being reflected on the fluorescent wheel. Because the emission of the fluorescent wheel to the fluorescence is similar to that of a lambertian body to emit light, the fluorescence can be emitted through the optical axis of the collimating mirror, so that the difference of the emitting positions of the laser and the fluorescence is small, and the light mixing effect of the laser and the fluorescence is improved. In addition, the laser emitted by the laser device is converged by the converging mirror and then emitted to the transmission region in the light converging mirror, and the area of the transmission region is small because the light spot formed by the laser after the laser is converged by the converging mirror can be small. Even if the laser is reflected on the fluorescent wheel, passes through the collimating mirror and then is emitted to the light-combining mirror, part of the laser passes through the transmission area to be lost, the lost laser is less, and the high utilization rate of the laser can be ensured.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, 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 projection light source provided in an embodiment of the present application;

FIG. 2 is a schematic diagram of a partial structure in a projection light source according to an embodiment of the present disclosure;

FIG. 3 is a schematic structural diagram of a fluorescent wheel provided in an embodiment of the present application;

FIG. 4 is a schematic structural diagram of another projection light source provided in the embodiments of the present application;

fig. 5 is a schematic structural diagram of a color filter wheel according to an embodiment of the present disclosure;

fig. 6 is a schematic view of a combination structure of a fluorescent wheel and a color filter wheel according to an embodiment of the present disclosure;

FIG. 7 is a schematic diagram of a projection light source according to another embodiment of the present disclosure;

FIG. 8 is a schematic structural diagram of another projection light source provided in an embodiment of the present application;

fig. 9 is a schematic structural diagram of a projection light source according to another embodiment of the present application.

Detailed Description

To make the objects, technical solutions and advantages of the present application more clear, embodiments of the present application will be described in further detail below with reference to the accompanying drawings.

With the development of the optoelectronic technology, lasers are widely used as light sources in projection devices. At present, the laser emitted by the laser excites the fluorescent wheel to emit fluorescent light, and the mode of forming a projection picture by the laser and the fluorescent light is also wide. In order to ensure the effective utilization of the light emitted from the fluorescent wheel, a collimating mirror may be disposed in front of the fluorescent wheel, and the fluorescent wheel may be located at a focal plane of the collimating mirror to ensure that the light emitted from the fluorescent wheel can be collimated by the collimating mirror. In this way, the laser light emitted to the fluorescent wheel is also converged to the fluorescent wheel through the collimator lens, and the laser light is approximately converged to a small spot on the fluorescent wheel, so that the power density of the laser light on the fluorescent wheel is high. The fluorescent material on the fluorescent wheel has low fluorescence excitation efficiency when the power density of the received laser is high, so that the efficiency of the fluorescent wheel for emitting fluorescence is low, the overall luminous efficiency of the projection light source is low, and the display effect of a projection picture formed by the projection light source is further influenced.

The embodiment of the application provides a projection light source and projection equipment, and the efficiency that this projection light source sent fluorescence is higher, and this projection light source's whole luminous efficiency is higher, and then the display effect that adopts the light that this projection light source sent to form the projection picture can be better.

Fig. 1 is a schematic structural diagram of a projection light source according to an embodiment of the present application. As shown in fig. 1, the projection light source 10 may include: the laser 101, the converging mirror 102, the light combining mirror 103, the dodging portion 104, the collimating mirror 105 and the fluorescent wheel 106 are sequentially arranged along a first direction (such as a y direction). The light combining mirror 103 includes a transmissive region 1031 and a reflective region 1032 surrounding the transmissive region 1031. The light uniformizing section 104 is located in a central area of the surface of the collimator lens 105 near the light combining lens 103, and the light uniformizing section 104 may pass through the optical axis of the collimator lens 105. An orthographic projection of the transmissive area 1031 covers an orthographic projection of the light uniformizing section 104 on a plane perpendicular to the first direction.

The laser 101 is configured to emit laser light to the condenser lens 102, and the condenser lens 102 is configured to condense the laser light to the transmission region 1031 of the light combining lens 103. The transmission region 1031 is configured to transmit the received laser light to the light uniformizing section 104, the light uniformizing section 104 is configured to homogenize the received laser light, and the homogenized laser light may be emitted to the fluorescence wheel 106 through the collimator lens 105. The laser beam can enter the fluorescent wheel 106 through the optical axis of the collimator lens 105, and the incident direction can be parallel to the optical axis of the collimator lens 105, so that the deviation between the central line of the laser beam and the optical axis of the collimator lens 105 is small. Such as the laser center line, may coincide with the optical axis of the collimating mirror 105. The laser described in the embodiments of the present application is referred to as a laser beam. In the embodiment of the present application, the dodging portion 104 and the collimating lens 105 are integrally formed, and there is no interface between the dodging portion 104 and the collimating lens 105, which changes the transmission direction of the light.

The fluorescent wheel 106 includes first and second circumferentially arranged regions, and the fluorescent wheel 106 may be configured to rotate, such as about its central axis. During rotation of the fluorescent wheel 106, different areas of the fluorescent wheel 106 receive the illumination of the laser light emitted by the collimator lens 105. The first region is used for reflecting the received laser light back to the collimating mirror 105, and the second region is used for emitting fluorescence to the collimating mirror 105 under the excitation of the received laser light. The first region may also be referred to as a laser-reflective region and the second region may be referred to as a fluorescent region. The collimating mirror 105 is further configured to collimate the light received from the fluorescent wheel 106 (i.e., the laser light reflected by the first region and the fluorescence excited by the second region) to the light combining mirror 103, and the reflecting region 1032 in the light combining mirror 103 is configured to reflect the received light, for example, reflect the received light in a second direction (e.g., x direction). As shown in fig. 1, the light combining mirror 103 may be inclined with respect to both the first direction and the second direction, for example, the first direction is perpendicular to the second direction, and both the included angles between the mirror surface of the light combining mirror 103 and the first direction and the included angles between the mirror surface of the light combining mirror 103 and the second direction may be 45 degrees, so as to ensure that the light emitted from the collimating mirror 105 along the direction opposite to the first direction is reflected along the second direction.

It should be noted that the collimator 105 has a convex arc surface close to the light combiner 103, and the converging and collimating functions of the collimator 105 on the light rays are mainly realized by the convex arc surface. In the embodiment of the present application, the center area of the convex arc surface is provided with the uniform light portion 104, which corresponds to replacing the arc surface portion of the center area with the uniform light portion 104. The laser beam emitted from the laser 101 is converged by the converging mirror 102 to the dodging portion 104, diffused and homogenized by the dodging portion 104, and then emitted to the fluorescent wheel 106 through the collimator lens 105. Because the convex arc surface of the collimating lens 105 does not accurately converge the incident laser light due to the substitution effect of the light homogenizing part 104 on the arc surface of the area where the light homogenizing part is located, the laser light can not be converged at one point but can form a light spot with a certain area after passing through the collimating lens 105 and being emitted to the fluorescent wheel 106. Therefore, the fluorescent region (i.e., the second region) of the fluorescent wheel 106 can be ensured to have a larger region irradiated by the laser, and the laser power density of the irradiated region is lower, so that the fluorescence excitation efficiency of the fluorescent region can be higher, and accordingly, the overall luminous efficiency of the projection light source can be higher. The shape of the spot may be the same as the beam shape of the laser light emitted by the laser 101. Such as a rectangular shape for the spot.

The fluorescence region of the fluorescence wheel 106 may emit light like a lambertian body when excited to emit fluorescence, which is emitted toward the collimator mirror 105 with a large divergence angle centered on the irradiation region of the laser light on the fluorescence region. Since the fluorescence covers a large area of the collimator lens 105 when it is emitted to the collimator lens 105, the fluorescence is transmitted through the collimator lens 105 and then emitted to an area of the convex arc surface of the collimator lens 105 where the light uniformizing portion 104 is not provided, and further emitted after being collimated by the convex arc surface. Thus, the collimator 105 can realize normal collimation of the fluorescence emitted from the fluorescent wheel 106 without accurately converging the laser emitted to the fluorescent wheel 106, and the fluorescence excitation efficiency can be improved on the basis of realizing the normal function of the collimator 105.

In the embodiment of the present application, the light uniformizing part 104 is located in the central region of the collimator mirror 105, and the direction in which the laser light enters the fluorescent wheel 106 is parallel to the optical axis of the collimator mirror 105, so that the laser light can also be emitted along the optical axis of the collimator mirror 105 after being reflected by the laser light reflecting region of the fluorescent wheel 106, and the fluorescent light emitted from the fluorescent region of the fluorescent wheel 106 is also emitted along the optical axis of the collimator mirror 105. Since the fluorescence emitted from the fluorescence area of the fluorescence wheel 106 is emitted along the optical axis of the collimating mirror 105, the emitting directions of the laser and the fluorescence are consistent well, the mixing uniformity of the fluorescence and the laser can be good, and the color uniformity of the image when the projection image is formed based on the fluorescence and the laser is high. In addition, both the laser and the fluorescence emitted by the fluorescence wheel 106 can be emitted to the collimating mirror 105 from the central area of the collimating mirror 105, so that the collimating mirror 105 can collect the laser and the fluorescence as much as possible, thereby facilitating subsequent utilization and reducing the waste of the fluorescence and the laser.

In an alternative example, the laser light reflecting region in the fluorescent wheel 106 may diffusely reflect the laser light. Therefore, the divergence angle of the laser reflected by the fluorescence wheel 106 is close to the divergence angle of the fluorescence emitted by the fluorescence wheel 106, the transmission process of the laser is similar to the transmission process of the fluorescence, the mixing uniformity of the laser and the fluorescence can be ensured to be higher, and the consistency of the light spots of the laser and the fluorescence is higher. The transmission of the laser light reflected by the fluorescence wheel 106 in the collimator 105 and the collimation process of the laser light by the collimator 105 may refer to the above description for fluorescence, and the embodiments of the present application are not described again. For example, the laser light reflection region may be provided with a diffuse reflection material to achieve diffuse reflection of the laser light. Such as the diffuse reflective material may comprise sodium silicate or barium sulfate, etc.

In the embodiment of the present application, part of the light passing through the collimating mirror 105 and toward the light combining mirror 103 may exist to be directed to the transmission region 1031 in the light combining mirror 103. Since the transmissive region 1031 is used for transmitting laser light from the laser 101, the laser light emitted from the collimator mirror 105 to the transmissive region 1031 is also emitted from the transmissive region 1031, which causes a loss of the laser light. In order to ensure the light emitting efficiency of the projection light source 10, the loss of the laser light needs to be reduced as much as possible, for example, the loss of the laser light can be reduced by reducing the area of the transmissive region 1031 as much as possible.

Illustratively, the area of the transmission region 1031 may be ensured to be small by the action of the converging mirror 102. The converging lens 102 may include at least one convex lens, and fig. 1 illustrates the converging lens 102 as a plano-convex lens. The converging mirror 102 may converge the laser light emitted from the laser 101 to reduce a formed spot of the laser light emitted from the laser 101. In this way, the laser beam emitted from the converging mirror 102 forms a small spot on the light combining mirror 103, and the area of the transmission region 1031 in the light combining mirror 103 can be small, that is, the laser beam can be transmitted. Even if the laser is reflected on the fluorescent wheel, passes through the collimating mirror and then is emitted to the light-combining mirror, part of the laser passes through the transmission area to be lost, the lost laser is less, and the high utilization rate of the laser can be ensured.

The transmissive region 1031 in the light combining mirror 103 may be circular, rectangular or other shapes, which is not limited in the embodiments of the present application. Alternatively, the area of the transmission region 1031 may be ensured to be small by appropriate shape setting of the transmission region 1031 in the combiner 103. The shape of the transmissive region 1031 may be matched with the shape of a spot formed by the laser light emitted by the laser 101, so as to ensure that the area of the transmissive region 1031 is as small as possible on the basis of projection of the laser light emitted by the laser 101. In the embodiment of the present application, the area of the transmission region 1031 in the light combining mirror 103 is small, so that even in the light emitted from the collimating mirror 105 to the light combining mirror 103, the laser light emitted to the transmission region 1031 will be emitted from the transmission region 1031 to cause loss, and the amount of the lost light is small, and the amount of the light emitted by the projection light source 10 can still be ensured to be sufficient.

There are many alternative implementations of the light combining mirror 103. In an alternative implementation, the transmission region 1031 in the light combining mirror 103 may be a hollow region. For example, the light combining mirror 103 can be obtained by hollowing out a middle region of a reflective substrate. In another alternative implementation, the transmission region 1031 in the combiner 103 is made of a transparent material. For example, the light combining mirror 103 can be obtained by attaching a reflective film on the surface of a transparent substrate, and making the reflective film not cover the middle region of the transparent substrate. Optionally, a dichroic film may be attached to the transmission region 1031 in the light combining mirror 103, and the dichroic film may be used to transmit the laser light emitted from the laser 101 and reflect the fluorescence light emitted from the fluorescence region of the fluorescence wheel 106.

In summary, in the projection light source provided in the embodiment of the present application, the light uniformizing portion is disposed in the central area of the surface of the collimating mirror, which is close to the light combining mirror, and the laser emitted by the laser device can be emitted to the light uniformizing portion through the transmission areas of the converging mirror and the light combining mirror, and then the laser is homogenized and then emitted to the fluorescent wheel through the collimating mirror. The dodging part on the surface of the collimating lens can enable the collimating lens not to converge the incident laser, so that the laser which is emitted to the fluorescent wheel can form a light spot with a certain area on the fluorescent wheel, the laser power density on the second area of the fluorescent wheel is small, and the fluorescence excitation efficiency of the second area is high. Therefore, the efficiency of the projection light source for emitting fluorescence is high, and the overall luminous efficiency of the projection light source is high.

And for the laser and the fluorescence emitted by the fluorescence wheel, the collimating lens can still collimate the laser and the fluorescence and then emits the laser and the fluorescence to the light-combining lens. And the laser emitted by the laser is emitted to the fluorescent wheel through the light homogenizing part positioned in the central area of the collimating mirror, and the laser can be emitted through the optical axis of the collimating mirror after being reflected on the fluorescent wheel. Because the emission of the fluorescent wheel to the fluorescence is similar to that of a lambertian body to emit light, the fluorescence can be emitted through the optical axis of the collimating mirror, so that the difference of the emitting positions of the laser and the fluorescence is small, and the light mixing effect of the laser and the fluorescence is improved. In addition, the laser emitted by the laser device is converged by the converging lens and then emitted to the transmission area in the light converging lens, and the area of the transmission area is small because the light spot formed by the laser converged by the converging lens can be small. Even if the laser is reflected on the fluorescent wheel, passes through the collimating mirror and then emits to the light-combining mirror, part of the laser passes through the transmission area to be lost, the lost laser is less, and the high utilization rate of the laser can be still ensured.

Alternatively, the laser light emitted by the laser 101 may be blue laser light. The blue laser has a high excitation efficiency for the fluorescence, which can ensure a high fluorescence emission efficiency of the fluorescence region in the fluorescence wheel 106.

In the embodiment of the present application, the collimator 105 may be a convex lens or a lens group composed of a plurality of convex lens groups. Fig. 1 exemplifies that the collimator lens 105 includes two plano-convex lenses, which are a first lens 1051 and a second lens 1052, respectively, arranged in order along the y direction. The plano-convex lens comprises a convex arc surface and a plane surface which are opposite, and the convex arc surfaces of the first lens 1051 and the second lens 1052 are close to the light combining lens 103 relative to the plane surface. The uniform light portion 104 may be located in a central area of the surface of the first lens 1051 near the light-combining mirror 103. The laser light transmitted by the light combining mirror 103 enters the first lens 1051 through the dodging portion 104, and the dodging portion 104 can disable the converging action of the first lens 1051 on the entering laser light, thereby destroying the overall converging action of the collimating mirror 105 on the entering laser light.

Since the laser light is emitted to the fluorescent wheel 106 after being converged by the converging mirror 102 and the second lens 1052 as a whole, the focal length of the converging mirror 102 combined with the second lens 1052 affects the converging position of the laser light, and the laser light can be converged at the focal length of the converging mirror 102 combined with the second lens 1052. The combined focal length of the converging mirror 102 and the second lens 1052 in the embodiments of the present application may be greater than the distance between the second lens 1052 and the fluorescent wheel 106. Therefore, the laser can be ensured to be emitted to the fluorescent wheel 106 before being converged to one point, a spot with a certain area can be formed on the fluorescent wheel 106 by the laser, and the power density of the laser on the fluorescent wheel 106 is ensured to be low. Alternatively, the focal length of the converging mirror 102 may be greater than the distance between the converging mirror 102 and the fluorescent wheel 106. Even if the collimator lens 105 includes only one convex lens and the convex lens loses the converging effect on the laser light emitted from the light combining lens 103, it is ensured that the laser light does not converge to a point on the fluorescent wheel 106.

The smoothing section 104 in the embodiment of the present application may include a microlens array. The microlens array may include a plurality of microlenses that may be arranged in an array. The microlenses, i.e. the lenses having relatively small dimensions, may have a rectangular shape in the orthographic projection of each microlens, e.g. in a plane perpendicular to the optical axis of the collimator 105, and the width of the rectangle may be less than 1 mm, e.g. the width may be 0.8 mm, 0.5 mm or 0.3 mm. Alternatively, the number of the microlenses in the dodging portion 104 may be more than 30. The micro-lens array is small in size and large in number, and can guarantee a better homogenization effect of the micro-lens array on the injected laser.

Optionally, the light exit angle of each microlens in the microlens array in the length direction of the rectangle is larger than the light exit angle in the width direction. The light-emitting angle in any direction is also an angle between a point to which parallel light is converged after entering the microlens and an effective diameter of the microlens in the direction, i.e., an angle between a line segment from the point to one end of the effective diameter and a line segment from the point to the other end of the effective diameter. The light emitting angle in the width direction may be less than 5 degrees, for example, the light emitting angle may be 3 degrees or 4 degrees. The light-emitting angle of the micro lens is small in the embodiment of the application, so that the area of a light spot formed by laser after passing through the micro lens array is small. Alternatively, the focal length of each microlens may be less than the focal length of the collimator lens 105. The light uniformizing part 104 may also realize the light uniformizing function through other structures, for example, the light uniformizing part 104 may include a diffuser, and the embodiment of the present application is not limited.

In the embodiment of the present application, the proportion of the position of the uniformizing section 104 on the collimator lens 105 may be small. Since a part of the light emitted from the fluorescent wheel 106 after passing through the collimator lens 105 and being directed to the light uniformizing section 104 cannot be collimated effectively, the part of the light is transmitted in a transmission direction required later, and the part of the light may be lost. The light spot formed on the light combining mirror 103 by the light (e.g., laser light and fluorescent light) emitted from the collimator mirror 105 may be substantially circular with a notch in the central region. In the embodiment of the present application, the position of the light uniformizing portion 104 on the collimator lens 105 is small, so that the light emitted from the fluorescent wheel 106 through the light uniformizing portion 104 is small, and even if the loss of the part of the light occurs, the loss of the light is small, so that the projection light source can still emit a large amount of light which can be effectively utilized, and the light emitting efficiency of the projection light source is high.

Fig. 2 is a schematic diagram of a partial structure in a projection light source provided in an embodiment of the present application, where the partial structure includes a light uniformizing portion 104 and a collimating mirror 105. Fig. 2 may be a top view of the dodging portion 104 and the collimator 105 in the projection light source shown in fig. 1. As shown in fig. 2, the area of the orthographic projection of the dodging portion 104 may be less than 10% of the area of the orthographic projection of the collimator mirror 105 on a plane perpendicular to the optical axis of the collimator mirror 105 (i.e., on a plane perpendicular to the y direction). For example, the area of the orthographic projection of the dodging portion 104 may account for 8%,5% or 3% of the area of the orthographic projection of the collimator mirror 105. For example, when the collimator lens 105 includes a plurality of lenses, the ratio may be an area ratio of an orthogonal projection of the light uniformizing section 104 to an orthogonal projection of one lens in which the light uniformizing section 104 is located. As for the collimator lens 105 shown in fig. 1, the area of the orthographic projection of the dodging portion 104 on the plane perpendicular to the y direction may be less than 5% of the area of the orthographic projection of the first lens 1051.

Fig. 3 is a schematic structural diagram of a fluorescent wheel provided in an embodiment of the present application, and fig. 3 is a top view of the fluorescent wheel in fig. 1. Referring to fig. 1 and 3, the fluorescent wheel 106 may include a laser reflection area 1061 and a fluorescent area 1062 arranged along the circumferential direction. The fluorescent wheel 106 can be rotated about the rotation axis z in the w direction or in the opposite direction of the w direction so that the laser light emitted from the collimator mirror 105 to the fluorescent wheel 106 is switched between the laser reflection area 1061 and the fluorescent area 1062. For example, the fluorescent wheel 106 may be rotated by a motor. Optionally, the fluorescent wheel 106 may have a circular shape or a circular ring shape, and the fluorescent area 1062 and the laser reflection area 1061 in the fluorescent wheel 106 may have a fan shape or a fan-shaped ring shape, which is taken as an example in the embodiment of the present application that the fluorescent wheel 106 has a circular ring shape. The ring surface of the ring may intersect with the first direction (y direction), the rotation axis z may be parallel to the y direction, and the rotation axis z may pass through the center of the ring and be perpendicular to the ring surface of the ring. Alternatively, the phosphor zones 1062 in the phosphor wheel 106 may include a reflective substrate with a phosphor material (e.g., phosphor) disposed thereon. The fluorescent light emitted by the fluorescent material under the excitation of the laser light can be reflected by the reflective substrate to exit toward the collimating mirror 105.

In the embodiment of the present application, the fluorescent area 1062 and the laser reflection area 1061 in the fluorescent wheel 106 are two continuous areas independent from each other. Phosphor zones 1062 may be a continuous area. Only one fluorescent material may be provided in this region, e.g. the fluorescent material is a yellow fluorescent material. Alternatively, the region may comprise a plurality of sub-regions, different fluorescent materials being arranged in different sub-regions. As shown in fig. 3, the phosphor zone 1062 may include adjacent sub-zones G1 and G2. Optionally, two different color fluorescent materials are respectively disposed in the two sub-regions, and each fluorescent material is used for being excited to emit fluorescence of a corresponding color. A red fluorescent material is provided as in one of the two sub-regions for being excited to emit red fluorescence; a green fluorescent material is disposed in the other sub-region for being excited to emit green fluorescence. Alternatively, the areas of the sub-region G1, the sub-region G2, and the laser reflection region 1061 may all be equal. Alternatively, the fluorescent zone 1062 may also include three regions in which a green fluorescent material, a red fluorescent material, and a yellow fluorescent material are disposed, respectively.

Optionally, the laser reflection area 1061 and the fluorescence area 1062 in the fluorescence wheel 106 may also each include a plurality of sub-areas, and the sub-areas in the fluorescence area 1062 and the sub-areas in the laser reflection area 1061 may be disposed at intervals. Alternatively, the phosphor material of different sub-regions in phosphor zone 1062 may be different, or there may also be sub-regions where the same phosphor material is disposed. In the embodiment of the present application, the manner of dividing the sub-region in the fluorescence wheel 106, the area of each sub-region, and the fluorescent material disposed in the sub-region belonging to the fluorescence region 1062 are not limited. The fluorescent material disposed in the sub-region belonging to the fluorescent region 1062 may be designed based on the color components required for forming the projection screen, and the areas of the respective sub-regions of the fluorescent region 1062 and the laser reflection region 1061 may be designed according to the ratio of the light emitted therefrom to the light required to be obtained.

In the embodiment of the present application, the fluorescence region 1062 of the fluorescence wheel 106 is excited by laser to emit fluorescence with a wider spectrum and a lower purity, and the fluorescence can be spectrally narrowed by other subsequent processes. The fluorescence may be filtered, for example, by a filtering component, to achieve spectral limiting of the fluorescence. Alternatively, the fluorescence area 1062 of the fluorescence wheel 106 may be used to excite only one color of fluorescence, and the fluorescence of the one color may be processed by the filter component to obtain fluorescence of a plurality of colors. For example, the fluorescent region 1062 may be used only to be excited with yellow fluorescent light, which may be filtered by the filter member to obtain red fluorescent light and green fluorescent light.

Fig. 4 is a schematic structural diagram of another projection light source provided in an embodiment of the present application. As shown in fig. 4, in addition to the projection light source 10 shown in fig. 1, the projection light source 10 may further include: an exit lens 107 and a color filter wheel 109. The light combiner 103, the exit lens 107, and the color filter wheel 109 may be arranged in sequence along a second direction (i.e., the x-direction). Note that fig. 4 does not show the matte portion 104. Light originating from the collimator 105 that is reflected by the reflective region 1032 in the combiner 103 may be directed in a second direction towards the exit lens 107. The exit lens 107 may focus the received light to the color filter wheel 109 so that the light may pass through the color filter wheel 109 and then exit for subsequent use. The structure of the color filter wheel 109 may be similar to that of the fluorescent wheel 106, the color filter wheel 109 may include a filter region and a transmission region arranged along the circumferential direction, the filter region is similar to the fluorescent region 1062 in the fluorescent wheel 106, and the structure and the division of the color filter wheel 109 may refer to the description of the fluorescent wheel 106.

Fig. 5 is a schematic structural diagram of a color filter wheel according to an embodiment of the present application. As shown in fig. 5, the color filter wheel 109 may include a light-transmitting region 1091, a first color filter region 1092, and a second color filter region 1093. If the first color is red, the second color is green. The color filter wheel 109 may be configured to rotate and different regions of the color filter wheel 109 receive light exiting the exit lens 107 during rotation. The first color filter zone 1092 and the second color filter zone 1093 are used to filter the fluorescence received from the exit lens 107. The rotation of the color filter wheel 109 can be referred to the above description of the rotation of the fluorescent wheel 106, and is not described in detail in this application.

The division manner of the filter area in the filter wheel 109 matches the division manner of the area of the fluorescent area 1062 in the fluorescent wheel 106, and the rotation condition of the filter wheel 109 and the rotation condition of the fluorescent wheel 106 may match. Illustratively, the fluorescent region 1062 in the fluorescent wheel 106 includes a plurality of sub-regions of different colors, and the color filter wheel 109 may include a plurality of filter regions corresponding to the plurality of sub-regions one by one, and each filter region has the same color as the fluorescent material disposed in the corresponding sub-region. When the fluorescent wheel 106 rotates so that the laser reflection area 1061 receives the laser irradiation, the color filter wheel 109 also rotates to the transmission area 1091. When the fluorescent wheel 106 rotates, so that any sub-region in the fluorescent region 1062 receives the laser irradiation, the color filter wheel 109 also rotates accordingly, so that the light emitted from the exit lens 107 is received by the filter region corresponding to the sub-region.

It should be noted that, because the projection light source 10 has a small size, the light transmission speed is fast, and the transmission time of the laser light and the fluorescent light between different components in the projection light source 10 is short, the time consumption is not considered in the embodiments of the present application. In this way, when the fluorescent wheel 106 rotates to reflect the laser light in the laser reflection area 1061, the color filter wheel 109 may rotate to allow the light transmission area 1091 to receive the light emitted from the exit lens 107. When the fluorescent wheel 106 is rotated to make the fluorescent region 1062 emit fluorescent light of any color, the color filter wheel 109 may be rotated to make the color filter region 1091 receive the light emitted from the exit lens 107. The laser light reflected by the fluorescent wheel 106 can be emitted through the transparent region 1091 of the color filter wheel 109, and the fluorescent light of each color emitted by the fluorescent wheel 106 can be transmitted to the filter region of the corresponding color, and then filtered by the filter region to limit the spectrum and increase the purity. Therefore, the ordered emission of the laser with various colors can be ensured, and the high purity of the fluorescent light emitted by the projection light source is ensured.

Alternatively, when only one color of fluorescent material is disposed in the fluorescent area 1062 of the fluorescent wheel 106, the color filter wheel 109 may rotate to enable the plurality of color filter areas to sequentially receive the light emitted from the exit lens 107 during the rotation of the fluorescent wheel 106 to enable the fluorescent area 1062 to receive the irradiation of the laser light. Each filter area can filter the received fluorescence to obtain fluorescence with the same color as the filter area so as to obtain fluorescence with multiple colors, the limitation of the fluorescence spectrum of each color is realized, and the purity of the obtained fluorescence of each color is ensured to be higher.

Fig. 4 illustrates an example of two independent structures of the fluorescent wheel 106 and the color filter wheel 109 disposed at different positions in the projection light source 10. Alternatively, the fluorescent wheel 106 and the color filter wheel 109 may be two different regions in the same component. For example, the fluorescent wheel 106 and the color filter wheel 109 may be two regions on the same substrate, the two regions are arranged along the radial direction of the substrate, and one region may surround the other region. In the area where the fluorescence wheel 106 is located in the two areas, a part of the area is used for reflecting laser light and serves as a laser reflection area 1061; the remaining portion region is provided with a fluorescent material as a fluorescent region 1062. The other area on the substrate can be transparent, and part of the area is transparent or hollow as a transparent area 1091; the remaining portion area has a specific color as a filter area. The fluorescent wheel 106 and the color filter wheel 109 may be coaxially disposed and configured to rotate synchronously. The laser transmission region 1061 in the fluorescent wheel 106 may be opposite to the transmission region 1091 in the color filter wheel 109, and the fluorescent region 1062 in the fluorescent wheel 106 may be opposite to a plurality of filter regions in the color filter wheel 109.

Fig. 6 is a schematic structural diagram of a combination of a fluorescent wheel and a color filter wheel according to an embodiment of the present disclosure. As shown in fig. 6, the area where the fluorescent wheel 106 is located surrounds the area where the color filter wheel 109 is located. The phosphor zone 1062 in the phosphor wheel 106 may include three sub-zones, sub-zones G1, G2, and G3, respectively. For example, the three subregions are sequentially used for emitting green fluorescence, yellow fluorescence and red fluorescence respectively. The color filter wheel 109 may include three filter zones, i.e., a first filter zone 1092, a second filter zone 1093, and a third filter zone 1094. The three filter regions are green, yellow and red in color. As shown in fig. 6, the laser reflection area 1061 in the fluorescent wheel 106 is opposite to the light transmission area 1091 in the color filter wheel 109, the sub-area G1 in the fluorescent wheel 106 is opposite to the first filter area 1092 in the color filter wheel 109, the sub-area G2 in the fluorescent wheel 106 is opposite to the second filter area 1093 in the color filter wheel 109, and the sub-area G3 in the fluorescent wheel 106 is opposite to the third filter area 1094 in the color filter wheel 109.

When the combination structure of the fluorescent wheel 106 and the color filter wheel 109 shown in fig. 6 is adopted, the light emitted from the light combiner 103 needs to be transmitted along the first direction to be emitted to the color filter wheel 109, so the projection light source 10 may further include a reflector to turn the transmission direction of the light emitted from the light combiner 103. Fig. 7 is a schematic structural diagram of another projection light source provided in an embodiment of the present application. As shown in fig. 7, the projection light source 10 may adopt a combination structure of the fluorescent wheel 106 and the color filter wheel 109 shown in fig. 6, the projection light source 10 may further include a reflector 108, the reflector 108 may be arranged along the second direction with the light combining mirror 103, and the reflector 108, the exit lens 107 and the color filter wheel 109 are arranged along the first direction. The light emitted from the reflective region 1032 of the light combiner 103 may be directed to the mirror 108 in the second direction, the mirror 108 may reflect the received light to the exit lens 107, and the exit lens 107 may converge the received light to the color filter wheel 109 in the first direction.

Fig. 8 is a schematic structural diagram of another projection light source provided in an embodiment of the present application. As shown in fig. 8, on the basis of fig. 7, the projection light source 10 may further include a shaping lens 110, and the shaping lens 110 may be located between the light combining mirror 103 and the reflecting mirror 108. The shaping lens 110 is used to shape the light emitted from the light combining mirror 103 in the second direction so that the light is directed to the reflecting mirror 108 closer to parallel light.

Fig. 9 is a schematic structural diagram of a projection light source according to another embodiment of the present application. As shown in fig. 9, the projection light source 10 may further include a light guide 111 in addition to any of the above projection light sources. The light emitted from the color filter wheel 109 may be incident into the light pipe 111, and the light pipe 111 may homogenize the incident light and emit the homogenized light for subsequent use. Fig. 9 is a schematic view based on the projection light source 10 shown in fig. 8.

In summary, in the projection light source provided in the embodiment of the present application, the light uniformizing portion is disposed in the central area of the surface of the collimating mirror, which is close to the light combining mirror, and the laser emitted by the laser device can be emitted to the light uniformizing portion through the transmission areas of the converging mirror and the light combining mirror, and then the laser is homogenized and then emitted to the fluorescent wheel through the collimating mirror. The dodging part on the surface of the collimating lens can enable the collimating lens not to converge the incident laser, so that the laser which is emitted to the fluorescent wheel can form a light spot with a certain area on the fluorescent wheel, the laser power density on the second area of the fluorescent wheel is small, and the fluorescence excitation efficiency of the second area is high. Therefore, the efficiency of the projection light source for emitting fluorescence is high, and the overall luminous efficiency of the projection light source is high.

And for the laser and the fluorescence emitted by the fluorescence wheel, the collimating mirror can still collimate the laser and the fluorescence and then emits the laser and the fluorescence to the light-combining mirror. And the laser emitted by the laser is emitted to the fluorescent wheel through the light homogenizing part positioned in the central area of the collimating mirror, and the laser can be emitted through the optical axis of the collimating mirror after being reflected on the fluorescent wheel. Because the fluorescence wheel emits fluorescence similar to a lambertian body, the fluorescence can be emitted through the optical axis of the collimating mirror, so that the difference between the emitting positions of the laser and the fluorescence is small, and the light mixing effect of the laser and the fluorescence is improved. In addition, the laser emitted by the laser device is converged by the converging lens and then emitted to the transmission area in the light converging lens, and the area of the transmission area is small because the light spot formed by the laser converged by the converging lens can be small. Even if the laser is reflected on the fluorescent wheel, passes through the collimating mirror and then is emitted to the light-combining mirror, part of the laser passes through the transmission area to be lost, the lost laser is less, and the high utilization rate of the laser can be ensured.

The embodiment of the present application also provides a projection device, which may include the projection light source 10 described above. The projection device may also include a light valve and a lens. The light guide 111 of the projection light source 10 may emit light to a light valve, the light valve may modulate the incident light and emit the modulated light to a lens, and the lens may project the incident light to form a projection screen.

For example, the light valve may include a plurality of reflective sheets, each of the reflective sheets may be used to form a pixel in the projection image, and the light valve may reflect the laser light to the lens by the reflective sheet corresponding to the pixel to be displayed in a bright state according to the image to be displayed, so as to modulate the light. The lens barrel may include a plurality of lenses (not shown in the drawings). The laser emitted from the light valve can be sequentially transmitted to the screen through a plurality of lenses in the lens so as to realize the projection of the lens on the laser and realize the display of a projection picture.

The term "at least one of a and B" in the present application is only one kind of association relationship describing an associated object, and means that three kinds of relationships may exist, for example, at least one of a and B may mean: a exists alone, A and B exist simultaneously, and B exists alone. The term "A, B and at least one of C" means that there can be seven relationships that can mean: there are seven cases of A alone, B alone, C alone, both A and B, both A and C, both C and B, and both A, B and C. In the embodiments of the present application, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. The term "at least one" means one or more, and the term "plurality" means two or more, unless expressly defined otherwise.

As used in this specification and the appended claims, certain terms are used to refer to particular components, and it will be appreciated by those skilled in the art that a manufacturer may refer to a component by different names. This specification and claims do not intend to distinguish between components that differ in name but not function. In the following description and in the claims, the terms "include" and "comprise" are used in an open-ended fashion, and thus should be interpreted to mean "include, but not limited to. "substantially" means within an acceptable error range, within which a person skilled in the art can solve the technical problem to substantially achieve the technical result.

The above description is only exemplary of the present application and should not be taken as limiting, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims (10)

1. A projection light source, comprising: the laser, the converging lens, the light combining lens, the light homogenizing part, the collimating lens and the fluorescent wheel are sequentially arranged; the light-combining mirror comprises a transmission area and a reflection area surrounding the transmission area, and the even light part is positioned in the central area of the surface of the collimating mirror close to the light-combining mirror;

the laser device is used for emitting laser to the converging mirror, the converging mirror is used for converging the laser to the transmission area of the light converging mirror, the transmission area is used for transmitting the received laser to the light homogenizing part, the light homogenizing part is used for homogenizing the received laser, and the homogenized laser is emitted to the fluorescent wheel through the collimating mirror;

the fluorescent wheel comprises a first area and a second area, the first area is used for reflecting the received laser light to the collimating mirror, and the second area is used for emitting fluorescent light to the collimating mirror under the excitation of the received laser light; the collimating mirror is also used for collimating the light received from the fluorescent wheel and then transmitting the collimated light to the light-combining mirror, and the reflecting area in the light-combining mirror is used for reflecting the received light.

2. The projection light source of claim 1, wherein the homogenizer portion comprises a microlens array.

3. The projection light source of claim 2 wherein the microlens array comprises a plurality of microlenses, the microlens array satisfying at least one of the following conditions:

the number of the plurality of micro lenses is more than 30;

on a plane vertical to the optical axis of the collimating mirror, the orthographic projection of each micro lens is rectangular, and the width of the rectangle is less than 1 millimeter;

on a plane vertical to the optical axis of the collimating mirror, the orthographic projection of each micro lens is rectangular, and the light-emitting angle of each micro lens in the width direction of the rectangle is less than 5 degrees;

and the focal length of each micro lens is smaller than that of the collimating mirror.

4. The projection light source according to claim 1, wherein an area of an orthographic projection of the homocline portion is less than 10% of an area of an orthographic projection of the collimator lens on a plane perpendicular to the optical axis of the collimator lens.

5. The projection light source of claim 1, wherein the collimating mirror comprises a first lens and a second lens, the first lens is close to the light combining mirror relative to the second lens, and the light homogenizing part is located on the surface of the first lens close to the light combining mirror;

the combined focal length of the converging mirror and the second lens is larger than the distance between the second lens and the fluorescent wheel.

6. The projection light source of any of claims 1 to 5, wherein the focal length of the converging mirror is greater than the distance between the converging mirror and the fluorescent wheel.

7. The projection light source of any of claims 1 to 5, wherein the first region is configured to diffusely reflect the received laser light.

8. The projection light source of any of claims 1 to 5, wherein the projection light source further comprises an exit lens and a color filter wheel;

the light passing through the reflecting area in the light combining mirror is emitted to the outlet lens, and the outlet lens is used for converging the received light to the color filter wheel;

the color filtering wheel comprises a light transmitting area and a plurality of color filtering areas which are arranged along the circumferential direction, the color filtering wheel is configured to rotate, and light emitted by the outlet lens in the rotating process is emitted through different areas of the color filtering wheel.

9. The projection light source of claim 8, wherein the fluorescent wheel and the color filter wheel are coaxially disposed and configured to rotate synchronously; the first region of the fluorescent wheel is opposite the clear region in the color filter wheel and the second region of the fluorescent wheel is opposite the plurality of filter regions in the color filter wheel;

the projection light source further comprises a reflector, and the reflector is used for reflecting the light reflected by the reflecting area of the light combining mirror to the outlet lens.

10. A projection device, characterized in that the projection device comprises: the projection light source of any one of claims 1 to 9, and a light valve and lens;

the projection light source is used for emitting laser to the light valve, the light valve is used for modulating the incident laser and then emitting the modulated laser to the lens, and the lens is used for projecting the incident laser to form a projection picture.

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