WO2020134785A1

WO2020134785A1 - Laser light source and laser projection device

Info

Publication number: WO2020134785A1
Application number: PCT/CN2019/120637
Authority: WO
Inventors: 王强
Original assignee: 青岛海信激光显示股份有限公司
Priority date: 2018-12-28
Filing date: 2019-11-25
Publication date: 2020-07-02
Also published as: CN111381424A

Abstract

A laser light source (10) and a laser projector, the laser light source (10) comprising: a blue laser (101), a light condensing apparatus (102), and a fluorescent apparatus (103). The light condensing apparatus (102) is located between the blue laser (101) and the fluorescent apparatus (103); the blue laser (101) emits blue laser light; the light condensing apparatus (102) refracts received blue laser light to obtain non-collimated blue laser light, and then transmits same to the fluorescent apparatus (103); the fluorescent apparatus (103) is a tubular structure, at least part of a region of an inner surface of the fluorescent apparatus (103) is a fluorescent region, the fluorescent region emits fluorescent light under the excitation of the blue laser light, and a tube wall of the fluorescent apparatus (103) reflects received blue laser light and fluorescent light; and the fluorescent apparatus (103) outputs different colored lights.

Description

Laser light source and laser projection equipment

This application requires the priority of the Chinese patent application filed on December 28, 2018, with the application number 201811628741.9 and the application name "laser light source and laser projection equipment", the entire contents of which are incorporated by reference in this application.

Technical field

The present application relates to the field of laser projection display, in particular to a laser light source and a laser projector.

Background technique

The laser light source is a light source with high brightness, strong directivity, and a monochromatic coherent light beam. Due to the many advantages of the laser light source, it has been gradually used in the field of projection display in recent years.

The structure of the current laser light source usually includes at least: a laser, a beam shaping device, a fluorescent wheel, a color filter wheel and a light rod. The working process of the laser light source includes: the laser emits laser light, and the laser beam undergoes a diameter reduction process (that is, the laser spot diameter is compressed) by a beam shaping device to obtain a diameter-reduced laser, and the diameter-reduced laser is irradiated on the fluorescent wheel On the top, a part is transmitted from the fluorescent wheel, and the other part excites the phosphor on the fluorescent wheel to output at least one color of fluorescence. The at least one color of fluorescence is filtered by the color wheel to obtain at least one color of light. The transmitted The laser and the light of at least one color are processed by the light rod to achieve the illumination function of the laser light source.

However, after the laser undergoes the diameter reduction process, the energy density of the laser irradiated on the phosphor is large, and after the energy density of the laser that excites the phosphor reaches a certain density, the excitation efficiency of the laser that excites the phosphor to the phosphor It has a certain influence, which makes the actual excitation efficiency of the phosphor negatively correlated with the energy density of the laser, that is, when the energy density of the laser that excites the phosphor is larger, the actually excited fluorescence is less. Therefore, the structure of the current laser light source is likely to cause the actual excitation efficiency of the phosphor to be low.

Summary of the invention

The embodiments of the present application provide a laser light source and a laser projection device, which can solve the problem of low excitation efficiency of phosphors. The technical solutions are as follows:

In a first aspect, a laser light source is provided, the laser light source comprising:

A blue laser, a light collecting device and a fluorescent device, the light collecting device is located between the blue laser and the fluorescent device;

The blue laser is used to emit blue laser;

The light collecting device is used to refract the received blue laser light to obtain a non-collimated blue laser light, and then transmit it to the fluorescent device;

The fluorescent device is a tubular structure, at least part of the inner surface of the fluorescent device is a fluorescent area, the fluorescent area is used to emit fluorescence under the excitation of a blue laser, and the tube wall of the fluorescent device is used for reflection and reception The blue laser and the fluorescence;

The fluorescent device is used to output different colors of light.

In a second aspect, a laser projector is provided. The laser projector includes:

An optical machine, a projection lens, and a laser light source, the laser light source is the laser light source described in the first aspect;

The optical machine is used to modulate the light beam to generate an image light beam when irradiated by the light beam emitted from the laser light source;

The projection lens is used to project the image beam onto the projection screen.

The technical solutions provided by the embodiments of the present application may include the following beneficial effects:

In the laser light source and the laser projector provided in the embodiments of the present application, since the fluorescent device in the laser light source has a reflection function, the effective light output of the fluorescent device is ensured, and the light collection efficiency of the laser light source for blue laser and fluorescence is improved. Further, because the condensing device refracts the blue laser to obtain a non-collimated blue laser, and the energy density of the non-collimated blue laser irradiated on the phosphor is smaller than that of the diameter-shrinked blue laser The energy density on the phosphor is small. When the non-collimated blue laser is irradiated onto the phosphor, the impact on the excitation efficiency of the phosphor is reduced, and the actual excitation efficiency of the phosphor is improved, thereby improving the The luminous efficiency of the laser light source. Therefore, the laser light source also improves the luminous efficiency of the laser light source while ensuring the collection efficiency of the blue laser light and the fluorescent light.

BRIEF DESCRIPTION

In order to more clearly explain the embodiments of the present application, the following will briefly introduce the drawings needed in the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. Ordinary technicians can obtain other drawings based on these drawings without paying any creative labor.

FIG. 1 is a schematic diagram of an implementation environment involved in some embodiments of the present application.

2 is a schematic structural diagram of a laser light source in the related art.

Fig. 3 is a schematic diagram of the divergence angle.

4 is a schematic structural diagram of a laser light source provided by an exemplary embodiment of the present application.

5 is a schematic cross-sectional view of a fluorescent device provided by an exemplary embodiment of the present application.

6 is a schematic structural diagram of a laser light source provided by an exemplary embodiment of the present application.

7 is a schematic structural diagram of a laser light source provided by an exemplary embodiment of the present application.

The drawings herein are incorporated into and constitute a part of this specification, show embodiments consistent with this application, and are used together with the specification to explain the principles of this application.

detailed description

In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be described in further detail with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments in this application, all other embodiments obtained by a person of ordinary skill in the art without making creative efforts fall within the scope of protection of this application.

Please refer to FIG. 1, which illustrates a schematic diagram of an implementation environment involved in some embodiments of the present application. The implementation environment may include: a laser light source 10, an optical machine 20, and a projection lens 30, and the laser light source 10, the optical machine 20, and the projection lens 30 are sequentially arranged along the beam transmission direction. Among them, the laser light source 10 is used to emit a light beam, the optical machine 20 is used to modulate the light beam to obtain an image light beam when the light beam emitted from the laser light source 10 is irradiated, and the projection lens 30 is used to project the image light beam onto the projection screen 40. Illustratively, the above-mentioned laser light source 10, optical machine 20 and projection lens 30 may be applied to the laser projector 1.

There are multiple laser light sources in current laser projectors. The laser light source may include: at least one laser, and the laser light source is used to emit laser light of at least one color. For example, the laser light source may be a monochromatic laser light source (that is, it includes a laser and the laser emits laser light of one color), or it may be a multicolor laser light source (that is, it includes multiple lasers and the laser emits laser lights of multiple colors in total) ). For example, when the laser light source is a monochromatic laser light source, one laser included in the laser light source may be a blue laser, a red laser, or a green laser; when the laser light source is a multicolor laser light source, the plurality of lasers may include blue Color laser, red laser and/or green laser.

As shown in FIG. 2, the laser light source 10 includes at least a fluorescent wheel 110, a color filter 120, a blue laser 130, a light combining member 140, a beam shaping member 150, and a light collecting member 160. The blue laser 130, the beam shaping member 150, the light combining member 140, the fluorescent wheel 110, the color filter 120, and the light collecting member 160 are arranged in this order along the transmission direction of the blue laser light. The blue laser 130 is used to emit blue laser light. The beam shaping member 150 is used to reduce the diameter of the blue laser emitted by the blue laser 130 to obtain a collimated blue laser beam after the diameter reduction, and transmit the collimated blue laser beam to the light combining member 140. The light combining component 140 is used to transmit the received blue laser to the fluorescent wheel 110, and the light combining component 140 is also used to transmit the blue component transmitted by the fluorescent wheel 110 to the color filter 120, and the blue component is irradiated by the blue laser After the transmissive area, the light component of the blue laser light transmitted by the transmissive area, the light combining part 140 is also used to transmit the fluorescent light emitted by the fluorescent wheel 110 to the color filter wheel 120, and the fluorescent light is generated by the blue laser light irradiating the fluorescent area. The color filter 120 is used to output red light, blue light, and green light in sequence when the light is rotated. The red light and green light are filtered by the color filter 120, and the blue light is transmitted by the color filter 120. Laser get. The light collecting part 160 is used to perform uniform light processing on red light, blue light and green light.

The light emitting process of the laser light source is as follows: the blue laser light emitted by the blue laser 130 is shaped by the beam shaping device 150 to the blue laser beam, then emitted to the light combining part 140, and then transmitted to the fluorescent wheel 110; Rotation, when the blue laser irradiates the transmission area on the fluorescent wheel 110, the blue laser is transmitted from the fluorescent wheel 110 and passes through the blue laser relay circuit optical path (referring to the blue laser transmitted from the fluorescent wheel 110 to the The light path of the light combining part 140) passes through the light combining part 140 again, and enters the light collecting part 160 after filtering the color wheel 120; when the blue laser irradiates the fluorescent area on the fluorescent wheel 110, the The phosphor emits at least one color of fluorescence (for example, yellow fluorescence and/or green fluorescence in FIG. 2 ), and the excited fluorescence is reversely transmitted, reflected by the light combining part 140 to the color wheel 120, and then enters the light collecting part 160 . After passing through the light collecting part 160, the three colors of light (referred to as tri-color light for short) generate an image beam by modulation of the optical machine 20, and the image beam is transmitted to the projection lens 30 to finally realize the image output of the tri-color light.

However, since the blue laser undergoes a diameter reduction process, the energy density irradiated on the phosphor is relatively large, and after the energy density of the laser that excites the phosphor reaches a certain density, the laser that excites the phosphor excites the phosphor The efficiency has a certain effect, which makes the actual excitation efficiency of the phosphor inversely related to the energy density of the laser, that is, when the energy density of the laser that excites the phosphor is larger, the actually excited fluorescence is less. Therefore, the structure of the current laser light source is likely to cause the actual excitation efficiency of the phosphor to be low.

To facilitate readers' understanding, the embodiments of the present application explain some definitions involved below.

Divergence angle θ: The beam divergence angle is the derivative of the beam radius with respect to the axial position of the far field. As shown in FIG. 3, the divergence angle is the angle between the two points p1 and p2 on the beam that are symmetric with respect to the optical axis L2 and the focal point, which is the focal point of the straight line L2 where the beam optical axis is located and the beam waist diameter L1.

Half divergence angle 1/2θ: half of the beam divergence angle. As shown in FIG. 3, the half divergence angle is the angle between the point p1 or p2 on the beam that is symmetrical with respect to the optical axis L2 and the focal line, which is the focal point of the straight line L2 where the beam optical axis lies and the beam waist diameter L1.

Color temperature: A unit of measurement that contains color components in light. Theoretically, the color temperature refers to the color presented by the absolute black body after heating from absolute zero (-273°C). If the light emitted by a certain light source has the same spectral component as the light emitted by a black body at a certain temperature, the color temperature of the certain light source is called the temperature of the black body plus 273K (Kelvin). For example, the color of the light emitted by a 100W (watt) bulb is the same as the color of an absolute black body at 2527K. The color temperature of the light emitted by the bulb is 2527K+273K=2800K.

Luminous flux: The total amount of light emitted by the luminous body per second, the unit is lm (lumens).

Excitation efficiency: the sum of the light emitted by the luminous body when it is excited by the energy per watt, the unit is lm/W.

Collimated light: The rays in the beam are parallel to each other.

Non-collimated light: that is, divergent light, that is, the light in the beam is not parallel.

Optical expansion: matching parameters of light source and lighting system.

Conservation of optical expansion: refers to the same optical expansion of the light source and the illumination system. Corresponding to the embodiment of the present application, the laser light source has the same optical expansion as the light valve and the projection lens.

The embodiments of the present application provide a laser light source, which can solve the above problems. Please refer to FIG. 4, which is a schematic structural diagram of a laser light source according to an embodiment of the present application. It is assumed that one laser in the laser light source is a blue laser. Then the laser light source 10 includes:

The blue laser 101, the condensing device 102, and the fluorescent device 103 are located between the blue laser 101 and the fluorescent device 103.

The blue laser 101 is used to emit blue laser light. For example, the blue laser is usually a collimated blue laser. The condensing device 102 is used to refract the received blue laser light to obtain a non-collimated blue laser light, and then transmit it to the fluorescent device 103. Exemplarily, the light-concentrating device 102 may be a lens with a refractive function, or a lens system with a refractive function, which is composed of multiple lenses. In practical applications, the light-concentrating structure 102 may be a convex lens. The non-collimated blue laser refers to a blue laser with a half divergence angle α, 0°<α<90°.

The fluorescent device 103 has a tubular structure, and at least part of the inner surface of the fluorescent device 103 is a fluorescent region (the black region on the inner surface of the fluorescent device 103 in FIG. 4 represents the fluorescent region). The fluorescent region is used under the excitation of a blue laser Fluorescence is emitted, and the wall of the fluorescent device 103 is used to reflect the received blue laser light and fluorescence. The fluorescent device 103 is used to output different colors of light. Exemplarily, the light of different colors may be light required by three primary colors. For example, the different colors of light may include yellow light, blue light, and green light, or red light, green light, and blue light, or red light, yellow light, and blue light, or yellow light, green light, red light, and blue light. It should be noted that the shape of the fluorescent area may be a ring shape or a bar shape, which is not limited in the implementation of this application.

Among them, in order to enable the fluorescent region to emit different colors of fluorescence under the excitation of the blue laser, the surface of the fluorescent region is provided with phosphors of different colors, so that when the fluorescent region is irradiated by the blue laser, it can be excited by Fluorescent powder of corresponding color to emit light of the color corresponding to the fluorescent powder. Therefore, the fluorescent area can be divided into a plurality of sub-fluorescence areas of corresponding colors according to the color of the set phosphor. Exemplarily, the color of the phosphor may be green, yellow, red, and/or orange, then the plurality of sub-fluorescence regions may include: a green sub-fluorescence region, a yellow sub-fluorescence region, and a red sub-fluorescence region, which correspond to the aforementioned colors one-to-one And/or orange sub-fluorescence zone.

The light emitting process of the laser light source 10 is as follows: the blue laser 101 emits blue laser light, and the blue laser light is refracted by the condensing device 102 to become a non-collimated blue laser light, and the non-collimated blue laser light enters the fluorescent device 103 Afterwards, the tube wall of the fluorescent device 103 is irradiated. Wherein, a part of the blue laser light irradiated to the fluorescent area on the inner surface of the tube wall excites the phosphor on the fluorescent area to output at least one color of fluorescence (yellow fluorescence and/or green fluorescence as shown in FIG. 4). Fluorescence of one color and a part of blue laser light irradiated to other areas of the tube wall (that is, areas other than the fluorescent area), multiple diffuse reflections through the wall of the tube (light incident at a second angle of incidence to the fluorescent area At this time, the reflection of the phosphor on the light is diffuse reflection) and output after reflection, and a part of the blue laser light that is not irradiated to the inner surface of the fluorescent device 103 is directly output to realize the illumination function of the laser light source.

In summary, in the laser light source provided by the embodiments of the present application, since the fluorescent device has a reflection function, the effective light output of the fluorescent device is ensured, and the light-receiving efficiency of the blue light and fluorescent light by the laser light source is improved. Further, because the condensing device refracts the blue laser to obtain a non-collimated blue laser, the energy density of the non-collimated blue laser irradiated onto the phosphor is compared to that of the diameter-shrinked blue laser The energy density irradiated onto the phosphor is small. When the non-collimated blue laser is irradiated onto the phosphor, the impact on the excitation efficiency of the phosphor is reduced, and the actual excitation efficiency of the phosphor is improved, thereby improving The luminous efficiency of the laser light source. Therefore, the laser light source also improves the luminous efficiency of the laser light source while ensuring the collection efficiency of the blue laser light and the fluorescent light.

Optionally, a part of the area in the inner surface of the fluorescent device 103 is a fluorescent area, and the fluorescent device 103 further has a reflective area. The orthographic projection of the reflective area on the inner surface of the fluorescent device covers the fluorescent area, and the reflective area covers the fluorescent area Area. The reflection area is used to reflect the light (blue laser and blue laser excited fluorescence) transmitted in the fluorescent device. For example, the reflective area includes a first reflective area and a second reflective area. Wherein, the orthographic projection of the first reflecting area on the inner surface of the fluorescent device does not overlap with the fluorescent area. The first reflecting area is usually farther away from the entrance of the fluorescent device than the fluorescent area (the entrance of the fluorescent device is close to the fluorescent device The opening at one end of the blue laser) is arranged. The first reflection area reflects the light transmitted in the fluorescent device multiple times (for example, total reflection of the light), so that the brightness of the light is more uniform, so as to achieve the homogenization of the light transmitted in the fluorescent device 103. The orthographic projection of the second reflecting area on the inner surface of the fluorescent device overlaps with the fluorescent area, such as the outer surface area and the tube wall area, etc. For example, the second reflecting area may be a reflective film coated on the inner surface of the fluorescent device Realization, correspondingly, the fluorescent zone can be realized by a fluorescent powder coated on the reflective film. The second reflection area reflects the light transmitted in the fluorescent device multiple times to avoid the loss of light in the fluorescent device, thereby ensuring the effective light emission of the fluorescent device, improving the light collection efficiency of the laser light source, and at the same time, The secondary reflection also makes the light more uniform. Therefore, due to the reflection area in the fluorescent device, the brightness of the output light is more uniform while ensuring the effective light emission of the fluorescent device, so that the laser light source can realize the uniform light treatment of the light without a light rod.

In practical applications, the fluorescent zone is usually located at the end of the fluorescent device 103 close to the blue laser 101, that is, at the end of the entrance of the fluorescent device. In this way, the fluorescent light emitted from the fluorescent area can be reflected by the reflection area more times, so that the brightness of the fluorescent light output by the fluorescent device is more uniform, and then the uniform light effect of the fluorescent device is stronger.

Optionally, the fluorescent device 103 may be a square tubular structure (that is, the cross-sectional shape of the fluorescent device is two nested rectangles, the cross-section is perpendicular to the extending direction of the fluorescent device), or a diamond-shaped tubular structure (that is, fluorescent The shape of the cross section of the device is two nested diamonds, the cross section being perpendicular to the direction of extension of the fluorescent device). Since the square tubular structure and the diamond-shaped tubular structure are axisymmetric, the difficulty of the manufacturing process is reduced.

In order to enable the tube wall of the fluorescent device 103 to reflect the received blue laser light and fluorescence, the tube wall of the fluorescent device 103 may be provided with a reflective film layer, for example, a highly reflective film layer with a reflectivity >90%. For example, the high-reflection film layer may be a high-reflection aluminum film or a high-reflection silver film. Alternatively, the tube wall of the fluorescent device 103 may also be made of a highly reflective material.

In practical applications, since the laser light source needs to satisfy the conservation of optical expansion, the laser light source 10 further includes: an angle filter 104, which is disposed at the end of the fluorescent device 103 away from the blue laser 101. The angle filter 104 is used to transmit light whose incident angle (that is, incident angle) is in the first angular range, and reflect light whose incident angle is in the second angular range, and the angle in the first angular range is smaller than the second angle The angle in the range. The union of the first angle range and the second angle range is 0-90. There is no intersection between the two, and the upper limit of the first angle range is less than the specified angle, and the lower limit of the second angle range is greater than the specified angle. For example, the angle filter may be a light-transmitting device with an optical film layer.

After determining the types of optical machine and projection lens in the configuration of the laser light source, according to the principle of conservation of optical expansion, the optical expansion of the laser light source is a fixed value, and the aforementioned specified angle is related to the optical expansion, so when determining When the optical expansion amount is obtained, the specified angle can be calculated according to the optical expansion amount. Among them, the relationship between the optical expansion U and the specified angle satisfies:

U=πA×sin2δ, A is the area of the fluorescent device irradiated by the beam, that is, the cross-sectional area of the fluorescent device, δ is the angle between the normal of the area irradiated by the beam and the optical axis of the solid angle of the beam, that is, Is the specified angle.

In the design of actual laser light sources, the color temperature of the light emitted from them is usually within a certain range. Therefore, it is necessary to match the optical power of different colors of light emitted from the laser light source. Because the color of the light is related to the laser and the phosphor, and because the power of the fluorescence of a certain color and the area of the coating of the phosphor of the color (that is, the sub-fluorescence region of the color), the blue laser light is irradiated to the The energy density of the sub-fluorescence zone of the color, the cross-sectional area of the fluorescent device, the optical power of the blue laser irradiated to the sub-fluorescence zone of the color, and the first incident angle of the blue laser irradiated to the sub-fluorescence zone of the color The range (that is, the range of the half divergence angle) is related. Therefore, when designing the area of each sub-fluorescence zone in the fluorescent device (that is, the area where each color phosphor is coated), the energy density and the first The optical angle range, the optical power of the blue laser irradiated to the sub-fluorescence region of the color, and the cross-sectional area of the fluorescent device. Wherein, the first incident angle range is the angle range of the angle between the transmission direction of the blue laser and the normal direction of the surface of the opening when the blue laser passes through the fluorescent device near the opening of the end of the blue laser.

For example, as described in FIGS. 4 and 5, assuming that the fluorescent device 103 has a square tubular structure, the shape of the cross section (the cross section is perpendicular to the extending direction of the fluorescent device) is two nested rectangles, that is, a “back” shape , The area of the inner rectangle (corresponding to the inner surface of the fluorescent device) of the two nested rectangles is a×b square millimeter, where a is the width of the inner rectangle, the unit is mm, and b is the inner rectangle The length of the rectangle is in millimeters. The inner surface of the fluorescent device 103 has a fluorescent area, and is located at the end of the fluorescent device 103 near the blue laser 101. The fluorescent region includes: a yellow sub-fluorescent region and a green sub-fluorescent region. The angle range of the semi-divergence angle γ of the blue laser is 0°-50°, the optical power of the blue laser is 100W, and the energy distribution is uniform, that is, The optical power of the blue laser per 1° is 1W, that is, the energy density is 1, the laser efficiency of the phosphors of each color is 300lm/W, according to the conservation of the optical expansion of the laser light source, the The maximum value of the first angle range of the incident angle of the light transmitted through the angle filter area is 10°, and it is assumed that the required color temperature of the laser light source is about 7500K.

Then, the maximum value of the first angle range of the incident angle of the blue laser transmitted through the angle filter area of the fluorescent device is 10°, which is the blue laser that is not used to excite the phosphor in the blue laser (i.e. blue In addition to the blue laser used to excite the phosphor, the maximum half divergence angle γ of the color laser is 10°, and the optical power of the blue light that is not irradiated on the phosphor is about 10× 2×1=20W (luminous flux is 612lm), the optical power of the blue laser emitted by the laser light source is about 20W, and the optical power of the blue light that is not irradiated on the phosphor is about 100-20=80W. The optical power is 80W, the luminous flux of fluorescence is 80W×300lm//W=24000lm, the maximum half divergence angle β angle of the blue laser (that is, the part of the blue laser used to excite the phosphor in the blue laser) irradiated to the fluorescent area It is 50-10=40°. According to the requirement of 7500K color temperature, the ratio of the light power of yellow light and blue light is determined to be 2:1, then the ratio of the luminous flux of yellow light and blue light is 2:1. The area ratio of the sub-fluorescence zone is 2:1. The total area of the fluorescent area is 2ab×[(tanβ-tanγ)/(tanγ×tanβ)], the area of the yellow fluorescent area is 2/3×2ab[(tanβ-tanγ)/(tanα×tanγ)], the green area The area of the fluorescent zone is 1/3×2ab[(tanβ-tanγ)/(tanγ×tanβ)]. The luminous flux of yellow light, green light and blue light output by the laser light source is 24000+612=24612lm.

Further, since the fluorescent device needs to output blue laser light, the length L of the fluorescent device satisfies: L>a×[(tanβ-tanγ)/(tanγ×tanβ)], and L>b×[(tanβ- tanγ)/(tanγ×tanβ)].

Further, since the fluorescence emitted from the fluorescent area of the fluorescent device is a Lambertian body, part of the fluorescence may be output to the entrance of the fluorescent device, and then exit through the entrance of the fluorescent device, and the light reflected by the angle filter may also be emitted from the The entrance of the fluorescent device is emitted. This will cause loss of light.

Based on this, the laser light source 10 provided by the embodiment of the present application further includes: a dichroic member 105, which is disposed at an end of the fluorescent device 103 close to the blue laser 101. The dichroic element 105 is used to transmit blue laser light (short-wavelength light) and reflect fluorescence (long-wavelength light). For example, the dichroic member 105 may be a light-transmitting device with an optical film layer, such as a color filter or a dichroic sheet. In this way, a part of the fluorescence output to the entrance of the fluorescent device and the light reflected by the angle filter are prevented from being emitted from the entrance of the fluorescent device, reducing the loss of light.

Optionally, the laser light source 10 further includes a color filter wheel 106, which is located on the side of the fluorescent device 103 away from the blue laser 101, and the color filter wheel 106 is used to output different colors of light in a sequential manner. For example, the color filter 106 is used to output red light, blue light, green light, and yellow light in time sequence; or, the color filter 106 is used to output red light, green light, and blue light in time sequence.

Since when the fluorescent region of the fluorescent device includes multiple sub-fluorescent regions, the fluorescent device will output different colors of light at the same time, therefore, the color filter 106 may include a red filter region, a green filter region, and a yellow filter region At least three color filter areas (red light filter area, green light filter area, yellow light filter area and blue light filter area) in the light filter area and blue light filter area, so that the laser light source can be at the same time Only one color of light is output. Wherein, the red light filter area is used for filtering the light of different colors output by the fluorescent device to obtain red light, and the green light filter area is used for filtering the light of different colors output by the fluorescent device to obtain green light and yellow The light filter area is used for filtering the light of different colors output by the fluorescent device to obtain yellow light, and the blue light filter area is used for filtering the light of different colors output by the fluorescent device to obtain blue light. Depending on the color of the light output by the color filter wheel, the color filter wheel may include different filter regions. For example, the different colors of light output by the color filter include red light, yellow light, green light, and blue light. Correspondingly, the color filter includes red light filter area, yellow light filter area, green light filter area, and blue light Filter area; the light of different colors output by the color wheel includes red light, green light and blue light. Correspondingly, the color wheel includes red light filter area, green light filter area and blue light filter area.

Then, the light emitting process of the laser light source 10 includes: the blue laser light emitted by the blue laser 101, which is refracted by the condensing device 102 to become a non-collimated blue laser light, and the non-collimated blue laser light enters The fluorescent device 103 is then irradiated onto the tube wall of the fluorescent device 103. Wherein, a part of the blue laser light irradiated to the fluorescent area on the inner surface of the tube wall excites the phosphor on the fluorescent area to output at least one color of fluorescent light, and the partial fluorescent light output to the entrance of the fluorescent device passes through the dichroic member 105 and the fluorescent device The reflection of the tube wall of 103 is transmitted to the angle filter 104; the other part of the fluorescence except the part of the fluorescence output to the entrance of the fluorescent device and the part of the blue laser that is not irradiated to the fluorescent area on the inner surface of the tube wall pass through the wall of the fluorescent device 103 It is reflected and transmitted to the angle filter 104; a part of the blue laser light that is not irradiated to the inner surface of the fluorescent device 103 is directly transmitted to the angle filter 104. The angle filter 104 transmits and outputs light (blue laser and fluorescence) with an incident angle of the first angle, reflects light with an incident angle of the second angle to the wall of the fluorescent device 103, and passes through the wall and the filter After the light sheet 105 diffusely reflects and reflects multiple times, the light at the first angle is output through the angle filter 104. Finally, different colors of light output from the fluorescent device 103, that is, fluorescent and blue laser light, are output to the color filter 106, and after filtering, they are emitted from the laser light source to realize the illumination function of the laser light source.

Optionally, as shown in FIG. 6, the laser light source 10 further includes a heat dissipation structure 107 that is disposed outside the tube wall of the fluorescent device 103. The heat dissipation structure 107 is used to dissipate the fluorescent device 103. For example, the heat dissipation structure 107 may be a patch radiator connected to the outside of the tube wall or a liquid cooling radiator surrounding the outside of the tube wall. Because the heat dissipation structure is provided on the outside of the tube wall of the fluorescent device, the problem of heat generated when the blue laser in the fluorescent device excites the phosphor can be effectively solved, and the life of the laser light source can be increased.

Please refer to FIG. 7, which is a schematic structural diagram of another laser light source 10 provided by an embodiment of the present application. Among them, FIG. 7 takes a laser light source as a two-color laser light source as an example for description. FIG. 7 assumes that one laser is a blue laser and the other laser is a red laser.

In FIG. 7, the laser light source 10 further includes a red laser 108 that is used to emit red laser light. Optionally, the laser light source 10 further includes a light combining part 109, and the light combining part 10 is used to transmit the received blue laser light and red laser light to the light collecting device 102. The structure and principle of the blue laser 101, the condensing device 102, the fluorescent device 103, the angle filter 104, the dichroic element 105, and the color wheel 106 in FIG. 7 can refer to the laser light source 10 shown in FIG. 4, This embodiment of the present application will not repeat them here.

Exemplarily, the light emitting process of the laser light source includes: blue laser light emitted by the blue laser 101 and red laser light emitted by the red laser 108. The laser light (which is a collective name of the red laser and the blue laser) is refracted by the condensing device 102 to become The non-collimated laser light enters the fluorescent device 103 and irradiates the tube wall of the fluorescent device 103. Wherein, a part of the laser light irradiated to the fluorescent area p on the inner surface of the tube wall excites the phosphor on the fluorescent area p to output at least one color of fluorescence (such as yellow fluorescence and/or green fluorescence in FIG. 5), which is output to the fluorescence Part of the fluorescence at the entrance of the device is reflected by the dichroic 105 and the tube wall of the fluorescent device 103 and transmitted to the output of the angle filter 104; the part of the laser light that is not irradiated to the fluorescent area p on the inner surface of the tube wall is output to the entrance of the fluorescent device The other part of the fluorescence is reflected by the wall of the fluorescent device 103 and transmitted to the output of the angle filter 104. The blue laser light that is not irradiated to the inner surface of the fluorescent device 103 is directly transmitted to the angle filter 104. The angle filter 104 transmits light (blue laser and fluorescence) with an incident angle of the first angle, reflects light with an incident angle of the second angle to the tube wall of the fluorescent device, passes through the tube wall and filters light After the sheet 105 is diffusely reflected and reflected multiple times, the light at the first angle is output through the angle filter 104. Finally, the different colors of light output from the fluorescent device 103, that is, fluorescence and laser light, are emitted to the color filter 106, and after filtering, they are emitted from the laser light source to realize the illumination function of the laser light source.

It should be noted that the red light emitted by the laser light source includes red laser light emitted by the red laser and/or red light obtained by filtering the yellow fluorescence through the filter color wheel.

The red laser light source in the laser light source shown in FIG. 7 may be replaced with a green laser, and the green laser is used to emit green laser light. At this time, the light emitting process of the laser light source is the same as the above light emitting process, which will not be repeated in the embodiments of the present application. It should be noted that the red light emitted by the laser light source is red light obtained by filtering the yellow fluorescent light through the color wheel. The green light emitted by the laser light source includes green laser light emitted by the green laser and/or green fluorescence light The green light obtained by the filtering treatment of the color wheel.

An embodiment of the present application provides yet another laser light source. The laser light source may be a three-color laser light source, then one laser may be a blue laser, the other laser may be a red laser, and the other laser may be a green laser. The light emitting process of the three-color laser and the above-mentioned two-color laser is basically the same, which will not be repeated in the embodiments of the present application.

In summary, in the laser light source provided by the embodiments of the present application, since the fluorescent device has a reflection function, the effective light output of the fluorescent device is ensured, and the light-receiving efficiency of the laser light source for blue laser and fluorescence is improved. At the same time, the reflection function So that the fluorescent device has a uniform light effect. Further, because the condensing device refracts the blue laser to obtain a non-collimated blue laser, and the energy density of the non-collimated blue laser irradiated on the phosphor is compared with that of the blue laser of the diameter reduction process The energy density irradiated on the phosphor is small. When the non-collimated blue laser is irradiated on the phosphor, the impact on the excitation efficiency of the phosphor is reduced, and the actual excitation efficiency of the phosphor is improved, thereby improving the The luminous efficiency of this laser light source. Therefore, the laser light source ensures the light-receiving efficiency of the blue laser light and the fluorescent light, and the luminous efficiency of the laser light source. At the same time, when the laser light source does not include a color filter, the laser light source can be used in a lighting system such as a flashlight. Since the laser light source can output multiple colors of light at the same time, its overall luminous efficiency is high.

Further, since the heat dissipation structure is provided on the outside of the tube wall of the fluorescent device, the problem of heat generated when the blue laser in the fluorescent device excites the phosphor powder is effectively solved, and the life of the laser light source is increased.

As shown in FIG. 1, an embodiment of the present application provides a laser projector. The laser projector includes a laser light source 10, an optical machine 20, and a projection lens 30. The laser light source 10 is any of the laser light sources described above. The optical machine 20 is located between the laser light source 10 and the projection lens 30. The optical machine 20 is used to modulate the light beam to generate a video light beam when irradiated with the light beam emitted from the laser light source 10. Exemplarily, the optical machine includes a light valve, and the light valve may be a digital micromirror device (English: Digital Micromirror Device, abbreviated as DMD). The projection lens 30 is used to project the image beam onto the projection screen 40.

In summary, the laser projector provided by the embodiment of the present application, because the fluorescent device of the laser light source in the laser projector has a reflection function, ensures the light collection efficiency of the laser light source for the blue laser and fluorescence. Further, because the condensing device refracts the blue laser to obtain a non-collimated blue laser, and the energy density of the non-collimated blue laser irradiated on the phosphor is smaller than that of the diameter-shrinked blue laser The energy density on the phosphor is small. When the non-collimated blue laser is irradiated onto the phosphor, the impact on the excitation efficiency of the phosphor is reduced, and the actual excitation efficiency of the phosphor is improved, thereby improving the laser. The luminous efficiency of the light source. Therefore, the laser light source not only ensures the collection efficiency of the blue laser and fluorescence, but also improves the luminous efficiency of the laser light source, thereby further improving the luminous efficiency of the laser projector.

After considering the description and practicing the invention disclosed herein, those skilled in the art will easily think of other embodiments of the present application. This application is intended to cover any variations, uses, or adaptive changes of this application, which follow the general principles of this application and include common general knowledge or customary technical means in the technical field not disclosed in this application . The description and examples are considered exemplary only, and the true scope and spirit of this application are pointed out by the claims.

It should be understood that the present application is not limited to the precise structure that has been described above and shown in the drawings, and various modifications and changes can be made without departing from the scope thereof. The scope of this application is limited only by the appended claims.

Claims

A laser light source, characterized in that the laser light source includes:

A blue laser, a light collecting device and a fluorescent device, the light collecting device is located between the blue laser and the fluorescent device;

The blue laser is used to emit blue laser;

The light collecting device is used to refract the received blue laser light to obtain a non-collimated blue laser light, and then transmit it to the fluorescent device;

The fluorescent device is a tubular structure, at least part of the inner surface of the fluorescent device is a fluorescent area, the fluorescent area is used to emit fluorescence under the excitation of a blue laser, and the tube wall of the fluorescent device is used for reflection and reception The blue laser and the fluorescence;

The fluorescent device is used to output different colors of light.
The laser light source according to claim 1, wherein the laser light source further comprises:

Angle filter, the angle filter is disposed at the end of the fluorescent device away from the blue laser, the angle filter is used to transmit light with an incident angle in the first angle range, and reflect the incident angle For light in the second angle range, the angle in the first angle range is smaller than the angle in the second angle range.
The laser light source according to claim 1, wherein the laser light source further comprises:

A dichroic element. The dichroic element is disposed at an end of the fluorescent device close to the blue laser. The dichroic element is used to transmit blue laser light and reflect fluorescence.
The laser light source according to claim 1, wherein

A part of the area in the inner surface of the fluorescent device is the fluorescent area, and the fluorescent device further has a reflective area, orthographic projection of the reflective area on the inner surface of the fluorescent device covers the fluorescent area, and the reflective area It is used to reflect the light transmitted in the fluorescent device.
The laser light source according to claim 4, characterized in that

The fluorescent area is located at an end of the fluorescent device close to the blue laser.
The laser light source according to claim 4, characterized in that

The tube wall of the fluorescent device is provided with a reflective film layer.
The laser light source according to claim 1, wherein

The fluorescent device is a square tubular structure.
The laser light source according to claim 1, wherein the laser light source further comprises:

A color filter wheel, the color filter wheel is located on a side of the fluorescent device away from the blue laser, and the color filter wheel is used to output light of different colors in a sequential manner;

The light of different colors output by the color filter includes: red light, yellow light, green light and blue light, and correspondingly, the color filter includes a red light filter area, a yellow light filter area and a green light filter area And blue light filter area;

Alternatively, the light of different colors output by the color filter includes: red light, green light and blue light, and correspondingly, the color filter includes a red light filter area, a green light filter area and a blue light filter area;

Wherein, the red light filtering area is used to filter the light of different colors to obtain red light;

The green light filtering area is used for filtering the light of different colors to obtain green light;

The yellow light filtering area is used for filtering the light of different colors to obtain yellow light;

The blue light filter area is used to filter the light of different colors to obtain blue light.
The laser light source according to claim 8, wherein the laser light source further comprises:

A red laser is used to emit red laser light, and the red laser light is incident on the color filter wheel through the fluorescent device.

And/or a green laser, the green laser is used to emit a green laser, and the green laser is incident on the color filter wheel through the fluorescent device.
A laser projector, characterized in that the laser projector includes:

An optical machine, a projection lens and a laser light source, the laser light source is the laser light source according to any one of claims 1 to 9;

The optical machine is used to modulate the light beam to generate an image light beam when irradiated by the light beam emitted from the laser light source;

The projection lens is used to project the image beam onto the projection screen.