CN113777868A - Optical illumination system and laser projection equipment - Google Patents

Abstract

The application discloses optical lighting system and laser projection equipment belongs to the projection display field. The optical illumination system includes: the device comprises a first laser, a second laser, a light combining lens group, a fly-eye lens and a light valve. The optical illumination system homogenizes the laser beam by adopting a fly-eye lens, and the fly-eye lens consists of a glass substrate, a micro lens arranged on the light incident surface of the glass substrate and a micro lens arranged on the light emergent surface of the glass substrate. The optical illumination system is small in size and can improve the homogenization effect of the laser beam.

Description

Optical illumination system and laser projection equipment

The present application claims priority from chinese patent application No. 202111038612.6 entitled "optical illumination system and laser projection apparatus" filed on 9/6/2021, the entire contents of which are incorporated herein by reference.

Technical Field

The present disclosure relates to projection display, and more particularly to an optical illumination system and a laser projection apparatus.

Background

With the development of the photoelectric technology, the requirements for the projection picture of the laser projection device are higher and higher. At present, in order to ensure the display brightness of a projection picture, a laser is generally adopted to provide illumination for a laser projection device, and a laser beam emitted by the laser has the advantages of good monochromaticity and high brightness, and is an ideal light source.

Laser projection devices may generally include: an optical illumination system and a projection lens. Fig. 1 is a schematic structural diagram of an optical illumination system provided in the related art. The optical illumination system generally includes: laser 01, light combining lens group 02, beam reducing lens group 03, diffusion plate 04, converging lens 05, light guide 06, lens group and light valve (not shown in fig. 1). The laser 01 and the light combining lens group 02 can be used together as a light source in a laser projection device. The laser 01 can emit green laser light, blue laser light, and red laser light at the same time. Laser emitted by a laser device 01 is emitted to the beam converging lens group 02 and then guided to the beam converging lens group 03, after being converged in the beam converging lens group 03, the laser sequentially passes through the diffusion plate 04 and the converging lens 05 and then is emitted to the light guide pipe 06, and after passing through the light guide pipe 06, the laser is guided to the light valve for modulation, and then is projected through the projection lens to form a projection picture. The light guide pipe 06 is used for homogenizing the laser beam to improve the imaging quality of the projection picture.

However, in order to achieve a good homogenization effect of the laser beam when the laser beam is incident on the light guide 06, the light guide 06 is required to have a long length, typically 30 mm or more. This leads to a large volume of the entire optical illumination system and thus to a large volume of the laser projection apparatus.

Disclosure of Invention

The embodiment of the application provides an optical lighting system and laser projection equipment. The laser beam homogenizing effect can be improved, and meanwhile, the miniaturization of an optical lighting system and laser projection equipment is also considered, and the technical scheme is as follows:

in one aspect, there is provided an optical illumination system comprising:

the device comprises a first laser, a second laser, a light combining lens group, a fly eye lens and a light valve;

the light combining lens group is positioned at the light emitting sides of the first laser and the second laser, the arrangement direction of the light combining lens group and the first laser is perpendicular to the arrangement direction of the light combining lens group and the fly eye lens, the arrangement direction of the second laser and the light combining lens group is parallel to the arrangement direction of the light combining lens group and the fly eye lens, and the second laser is positioned at one side of the light combining lens group away from the fly eye lens;

the first laser is used for emitting a first laser beam to the light combining lens group, the second laser is used for emitting a second laser beam to the light combining lens group, the light combining lens group is used for guiding the first laser beam and the second laser beam to the fly eye lens, and the fly eye lens is used for guiding the first laser beam and the second laser beam to the light valve;

the first laser and the second laser are respectively provided with a plurality of laser units which are arranged in an array mode, and the laser units are used for emitting laser of at least two colors; the light incident surface of the fly-eye lens is provided with a plurality of micro lenses arranged in an array;

in a target direction, the width of the micro lens is determined based on the width of a light spot formed on the light incident surface by the laser emitted by the laser unit and the width of the light valve, and the target direction is a fast axis direction or a slow axis direction of the laser.

In another aspect, there is provided a laser projection apparatus including: the optical illumination system and the projection lens are provided.

The beneficial effects brought by the technical scheme provided by the embodiment of the application at least comprise:

an optical illumination system comprising: the device comprises a first laser, a second laser, a light combining lens group, a fly-eye lens and a light valve. The optical illumination system can homogenize the laser beam by adopting a fly-eye lens, and the fly-eye lens consists of a glass substrate, a micro lens arranged on the light incident surface of the glass substrate and a micro lens arranged on the light emergent surface of the glass substrate. Therefore, the fly-eye lens is generally small in volume, effectively reducing the volume of the optical illumination system. Moreover, the optical illumination system does not need to be provided with a beam reduction lens group and a converging lens, so that the volume of the optical illumination system is further reduced. After the optical illumination system is integrated into the laser projection device, the volume of the laser projection device can be effectively reduced. In addition, the size of the microlens in the fly-eye lens may be determined according to the size of the spot of the laser unit and the size of the light valve. Therefore, the micro lens determined by the size of the light spot of the laser unit and the size of the light valve has better homogenization effect on the laser beams emitted by each laser unit.

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 an optical illumination system provided in the related art;

fig. 2 is a schematic structural diagram of an optical illumination system provided in an embodiment of the present application;

fig. 3 is a side view of the fly-eye lens shown in fig. 2;

fig. 4 is an optical path diagram of a fly-eye lens provided in an embodiment of the present application;

fig. 5 is a schematic diagram of a light spot formed by a laser unit provided in an embodiment of the present application;

FIG. 6 is a schematic structural diagram of another optical illumination system provided in the embodiments of the present application;

FIG. 7 is a diagram illustrating the effect of a laser beam impinging on the surface of a light valve;

FIG. 8 is a schematic structural diagram of another optical illumination system provided in the embodiments of the present application;

FIG. 9 is a schematic structural diagram of another optical illumination system provided in an embodiment of the present application;

fig. 10 is a schematic structural diagram of a laser projection apparatus according to an embodiment of the present application.

With the above figures, there are shown specific embodiments of the present application, which will be described in more detail below. These drawings and written description are not intended to limit the scope of the inventive concepts in any manner, but rather to illustrate the inventive concepts to those skilled in the art by reference to specific embodiments.

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.

Referring to fig. 2, fig. 2 is a schematic structural diagram of an optical illumination system according to an embodiment of the present disclosure. The optical illumination system 000 may include: a first laser 100, a second laser 200, a light combining lens 300, a fly-eye lens 400 and a light valve 500.

The light combining lens assembly 300 may be located at the light emitting sides of the first laser 100 and the second laser 200, and the arrangement direction (e.g., the Y-axis direction in fig. 2) of the light combining lens assembly 300 and the first laser 100 is perpendicular to the arrangement direction (e.g., the X-axis direction in fig. 2) of the light combining lens assembly 300 and the fly eye lens 400; the arrangement direction (e.g., X-axis direction in fig. 2) of the second laser 200 and the light combining lens assembly 300 is parallel to the arrangement direction of the light combining lens assembly 300 and the fly-eye lens 400, and the second laser 200 may be located at a side of the light combining lens assembly 300 away from the fly-eye lens 400.

The light valve 500 may be located on the side of the fly-eye lens 400 remote from the first laser 100. The light valve 500 may be configured to receive the first laser beam and the second laser beam emitted from the fly-eye lens 400, so as to modulate the first laser beam and the second laser beam and guide the modulated first laser beam and second laser beam to the projection lens.

The first laser 100 in the optical illumination system 000 may be configured to emit a first laser beam to the light combining lens assembly 300, and the second laser 200 may be configured to emit a second laser beam to the light combining lens assembly 300. The light combining lens assembly 300 may be configured to direct the first laser beam and the second laser beam to the fly-eye lens 400, and the fly-eye lens 400 may be configured to direct the first laser beam and the second laser beam to the light valve 500. Illustratively, the first laser beam emitted from the first laser 100 is parallel to the Y-axis direction in fig. 2, and the second laser beam emitted from the second laser 200 is parallel to the X-axis direction in fig. 2.

Therein, each of the first laser 100 and the second laser 200 in the optical illumination system 000 may have a plurality of laser units (not shown in fig. 2) arranged in an array, and the plurality of laser units may be configured to emit laser light of at least two colors. By way of example, the plurality of laser units may include: the laser system comprises a red laser unit for emitting red laser light, a green laser unit for emitting green laser light, and a blue laser unit for emitting blue laser light. For example, the plurality of laser units are arranged in four rows, and the four rows of laser units may include: two rows of red laser units for emitting red laser light, one row of green laser units for emitting green laser light, and one row of blue laser units for emitting blue laser light. In this way, the first laser 100 can emit red laser light, green laser light, and blue laser light simultaneously by the red laser unit, the green laser unit, and the blue laser unit; the second laser 200 can simultaneously emit red, green and blue laser lights through the red, green and blue laser units. It should be noted that, in the embodiments of the present application, the first laser 100 and the second laser 200 are schematically illustrated as examples of laser light that emits three colors, namely, blue laser light, green laser light, and red laser light simultaneously. The structure of the second laser 200 in the embodiment of the present application may be the same as that of the first laser 100. In other possible implementations, the first laser 100 and the second laser 200 may emit laser light of two colors, i.e., blue laser light and yellow laser light, simultaneously. The embodiment of the present application does not limit this.

In the present application, each of the plurality of laser units may include one light emitting chip, that is, each of the first laser 100 and the second laser 200 may include a plurality of light emitting chips arranged in an array, and each row of the plurality of light emitting chips is configured to emit laser light of the same color. For example, the first laser 100 includes light emitting chips arranged in four rows and six columns, where one row of light emitting chips is used for emitting blue laser light, one row of light emitting chips is used for emitting green laser light, and the other two rows of light emitting chips are used for emitting red laser light; the second laser 200 includes light emitting chips arranged in four rows and six columns, where one row of the light emitting chips is used to emit blue laser, one row of the light emitting chips is used to emit green laser, and the other two rows of the light emitting chips are used to emit red laser. In other possible implementation manners, the plurality of light emitting chips may also be arranged in other arrangement manners, which is not limited in this application embodiment.

In the present application, after a first laser beam emitted by the first laser 100 and a second laser beam emitted by the second laser 200 are emitted to the light combining lens assembly 300, the light combining lens assembly 300 reflects the first laser beam to the fly-eye lens 400, the light combining lens assembly 300 transmits the second laser beam to the fly-eye lens 400, and the fly-eye lens 400 is configured to homogenize the received laser beams.

As shown in fig. 3, fig. 3 is a side view of the fly-eye lens shown in fig. 2. The light incident surface of the fly-eye lens 400 in the optical illumination system 000 may have a plurality of microlenses 401 arranged in an array.

Here, in a target direction (as shown in fig. 3, the target direction may be a fast axis direction or a slow axis direction of the laser light), the width of the micro lens in the fly-eye lens 400 may be determined based on the width of the light spot formed on the light incident surface of the fly-eye lens 400 by the laser unit and the width of the light valve 500.

It should be noted that, the first laser 100 and the second laser 200 may both adopt semiconductor lasers, and the laser emitted by the semiconductor lasers has a fast axis and a slow axis. The divergence angle of the laser light in the fast axis direction is about +/-30 degrees, and the divergence angle of the laser light in the slow axis direction is about +/-10 degrees. After the laser beam emitted by the first laser 100 is collimated, the size of the light spot in the fast axis direction is larger than that in the slow axis direction, and the shape of the light spot may be rectangular or elliptical. The direction of the long side of the light spot is the fast axis direction, and the direction of the short side of the light spot is the slow axis direction.

For example, please refer to fig. 4, fig. 4 is an optical path diagram of a fly-eye lens provided in an embodiment of the present application. The fly-eye lens 400 in the optical illumination system 000 may include: the light source comprises a glass substrate 402, a plurality of micro lenses 401 arranged in an array on a light incident surface of the glass substrate 402, and a plurality of micro lenses 403 arranged in an array on a light emergent surface of the glass substrate 402. The microlenses 401 on the light incident surface and the microlenses 403 on the light emergent surface are in one-to-one correspondence, and the shape and size of each microlens 401 are the same as those of the corresponding microlens 403. For example, the microlenses 401 on the light incident surface and the microlenses 403 on the light emitting surface may be spherical convex lenses or aspheric convex lenses.

In this way, the plurality of microlenses 401 on the light incident surface can divide the spot of the laser light emitted by each laser unit. The divided light spots are accumulated by the microlenses 403 on the light-emitting surface, so that the laser beams emitted by the laser units can be homogenized, and the laser beams emitted by the first laser 100 and the second laser 200 can be homogenized.

In the embodiment of the present application, the optical illumination system 000 may use the fly-eye lens 400 to homogenize the laser beam, and the fly-eye lens 400 is composed of a glass substrate 402, and a micro lens 401 on the light incident surface and a micro lens 403 on the light emitting surface of the glass substrate 402. Accordingly, the fly-eye lens 400 is generally small in volume, effectively reducing the volume of the optical illumination system 000. Moreover, the optical illumination system 000 does not need to be provided with a beam reduction lens group and a converging lens, so that the volume of the optical illumination system 000 is further reduced. After the optical illumination system 000 is integrated into the laser projection apparatus, the volume of the laser projection apparatus can be effectively reduced. In addition, the size of the micro lens 401 in the fly-eye lens 400 may be determined according to the size of the spot of the laser unit and the size of the light valve 500. Therefore, the micro lens determined by the size of the light spot of the laser unit and the size of the light valve has better homogenization effect on the laser beams emitted by each laser unit.

In summary, the present application provides an optical illumination system, including: the device comprises a first laser, a second laser, a light combining lens group, a fly-eye lens and a light valve. The optical illumination system can homogenize the laser beam by adopting a fly-eye lens, and the fly-eye lens consists of a glass substrate, a micro lens arranged on the light incident surface of the glass substrate and a micro lens arranged on the light emergent surface of the glass substrate. Therefore, the fly-eye lens is generally small in volume, effectively reducing the volume of the optical illumination system. Moreover, the optical illumination system does not need to be provided with a beam reduction lens group and a converging lens, so that the volume of the optical illumination system is further reduced. After the optical illumination system is integrated into the laser projection device, the volume of the laser projection device can be effectively reduced. In addition, the size of the microlens in the fly-eye lens may be determined according to the size of the spot of the laser unit and the size of the light valve. Therefore, the micro lens determined by the size of the light spot of the laser unit and the size of the light valve has better homogenization effect on the laser beams emitted by each laser unit.

In the embodiment of the present application, the width d of the microlens in the target direction satisfies the following formula:

where D is the width of the light valve 500 in the target direction; theta is a lens imaging angle; t is the width of the light spot formed by the laser unit on the light incident surface of fly-eye lens 400 in the target direction; k is a scaling factor greater than 0.

It should be noted that, after the model of the light valve 500 is determined, the width of the light valve 500 in the target direction is determined, and therefore, the parameter D in the above formula is a fixed value; after the model of the projection lens in the laser projection device is determined, the imaging angle of the projection lens is a fixed value, for example, the imaging angle may be 120 ° or 150 ° or the like, and therefore, the parameter θ in the above formula is a fixed value; after the models of the chip of the first laser 100 and the chip of the second laser 200 are determined, the widths of the light spots formed on the light incident surface of the fly-eye lens 400 by the respective laser units in the first laser 100 and the second laser 200 in the target direction are fixed values.

For this reason, after the model of the light valve 500, the model of the projection lens in the laser projection apparatus, and the models of the chip of the first laser light 100 and the chip of the second laser light 200 are determined, the width of the microlens 401 disposed on the light incident surface of the fly-eye lens 400 in the fast axis direction and the width in the slow axis direction can be calculated by the above calculation formulas.

Referring to fig. 5, fig. 5 is a schematic diagram of a light spot formed by a laser unit according to an embodiment of the present disclosure. The light spot formed by the laser light emitted by each laser unit on the light incident surface of the fly-eye lens 400 overlaps with the region where the at least two micro lenses 401 are located. In this case, since the size of the microlens 401 disposed on the light incident surface of the fly-eye lens 400 is small, the spot formed on the light incident surface of the fly-eye lens 400 by the laser light emitted from each laser unit can correspond to at least two microlenses 401. Therefore, the fly-eye lens 400 has a good effect of homogenizing the laser beams emitted from the respective laser units.

Optionally, light spots formed by each laser unit on the light incident surface of the fly-eye lens 400 may overlap with regions where at least four microlenses arranged on the light incident surface of the fly-eye lens 400 are located, and the at least four microlenses are arranged in two rows and two columns in an array. For example, when the light spot formed by the laser unit on the light incident surface of the fly-eye lens 400 overlaps with the region where the four microlenses are located, the four microlenses may be arranged in two rows and two columns. In this way, the effect of homogenizing the laser beams emitted from the respective laser units by the fly-eye lens 400 can be further improved.

In the embodiment of the present application, the sizes of the respective microlenses in the fly-eye lens 400 are the same. For example, the width of the microlens in the fast axis direction and the width in the slow axis direction are both in the range of 0.1 mm to 1 mm.

Optionally, please refer to fig. 6, where fig. 6 is a schematic structural diagram of another optical illumination system provided in the embodiment of the present application. The optical illumination system 000 may further include: lens assembly 600 and prism assembly 700. The lens assembly 600 may be located on a side of the fly-eye lens 400 away from the light combining lens assembly 300, and both the lens assembly 600 and the light valve 500 may be located on a side of the lens assembly 600 away from the fly-eye lens 400. Wherein the lens assembly 600 may be used to guide the first laser beam and the second laser beam exiting from the fly-eye lens 400 to the prism assembly 700, and the prism assembly 700 may include: total Internal Reflection prism (TIR) prism. The prism assembly 700 can be configured to direct the first laser beam and the second laser beam to the light valve 500, and the light valve 500 can be configured to modulate the laser beams and direct the modulated laser beams to the projection lens.

For example, the light valve 500 may include a plurality of reflective sheets (not shown in the figure), each of which may be used to form one pixel in the projection image, and the light valve 500 may reflect the laser light to the projection lens according to the image to be displayed, so as to modulate the laser light beam, where the reflective sheet corresponding to the pixel that needs to be displayed in a bright state. For example, the light valve 500 may be a Digital micro-mirror Device (DMD).

Alternatively, referring to fig. 6 and 7, fig. 7 is a diagram illustrating the effect of the laser beam being irradiated onto the surface of the light valve. The center point of the light emitting surface of the fly-eye lens 400 may coincide with the focal point of the lens group 600. For example, a central point of the light exit surface of the fly-eye lens 400 may coincide with a focal point of the lens assembly 600 close to the light combining assembly. Thus, it can be ensured that the light beams emitted from each point of the light emitting surface of the fly-eye lens 400 are parallel light incident on the surface of the light valve 500 when being guided to the light valve 500.

In the embodiment of the present application, please refer to fig. 6, the light combining lens assembly 300 may include: a first mirror plate 301 and a second mirror plate 302. The first lens 301 and the second lens 302 are both disposed obliquely and located at the intersection of the two sets of laser beams. On a plane parallel to fly-eye lens 400, the orthographic projection of first mirror 301 is offset from the orthographic projection of second mirror 302. In this way, the first laser 100 may be used to emit blue and green laser light to the first mirror 301 and red laser light to the second mirror 302; the second laser 200 may be used to emit red laser light to the first mirror 301 and blue and green laser light to the second mirror 302. The first lens 301 may be configured to reflect the blue laser light and the green laser light emitted by the first laser 100 toward the fly-eye lens 400, and transmit the red laser light emitted by the second laser 200 toward the fly-eye lens 400; the second mirror 302 may be used to reflect the red laser light emitted from the first laser 100 toward the fly-eye lens 400, and transmit the blue and green laser light emitted from the second laser 200 toward the fly-eye lens 400.

In the embodiment of the present application, the first lens 301 and the second lens 302 in the light combining lens set 300 may be dichroic elements having different wavelength selective characteristics. For example, the first mirror 301 may be a dichroic plate that reflects blue laser light and green laser light, and transmits laser light of other colors; the second mirror 302 may be a dichroic plate that reflects red laser light and transmits laser light of other colors. Therefore, the first laser 100 and the second laser 200 combine light through a light combining lens with different wavelength selection characteristics, and the light path is compact and beneficial to miniaturization.

And, in another example, the first lens 301 and the second lens 302 in the light combining group 300 may be polarization elements having different polarization selection characteristics. For example, the first laser 100 and the second laser 200 respectively emit three-color laser beams with different polarization characteristics, taking red laser as P light and blue and green laser as S light as examples, the first lens 301 may be a polarizer that reflects S light, i.e., reflects blue and green laser beams, and transmits P light, i.e., transmits red laser beam; the second mirror 302 is a polarizer that reflects P light, i.e., red laser beam, and transmits S light, i.e., blue and green laser beams. Therefore, the first laser 100 and the second laser 200 combine light through a light combining lens group with different polarization selection characteristics, the light path is compact, and miniaturization is facilitated.

When the first laser 100 and the second laser 200 are combined by the wavelength selective characteristic, the optical illumination system 000 may further include: a first polarization conversion member 800 and a second polarization conversion member 900. The first polarization conversion component 800 may be located between the first laser 100 and the first lens 301, and the first polarization conversion component 800 may be configured to convert blue laser light and green laser light emitted by the first laser 100 from S-polarized light to P-polarized light, and then emit the P-polarized light to the first lens 202; the second polarization conversion member 900 may be located between the second laser 200 and the second lens 302, and the second polarization conversion member 900 may be configured to convert the blue laser light and the green laser light emitted from the second laser 200 into P-polarized light from S-polarized light and then emit the P-polarized light to the second lens 302. In this way, the polarization directions of the blue laser light and the green laser light incident on the fly-eye lens 400 are both the same as the polarization direction of the red laser light. Illustratively, the first polarization conversion member 800 and the second polarization conversion member 900 may each be a half-wave plate.

It should be noted that, in the above embodiments, the optical illumination system 000 includes two lasers for illustration, and in other alternative implementations, the number of the lasers in the optical illumination system 000 may also be one. Referring to fig. 8, fig. 8 is a schematic structural diagram of another optical illumination system provided in the embodiment of the present application. The optical illumination system includes: a first laser 100 and a light combining mirror group 300. There are various arrangements of the lenses in the light combining lens assembly 300, and the embodiment of the present application will be schematically described by taking the following two cases as examples:

in a first case, as shown in fig. 8, the light combining lens assembly 300 may include: a first mirror plate 301 and a second mirror plate 302. One side of the first lens 301 is attached to one side of the second lens 302. On a plane parallel to fly-eye lens 400, the orthographic projection of first mirror 301 is offset from the orthographic projection of second mirror 302. In this way, the first laser 100 may be used to emit a first laser beam to the first mirror 301 and the second mirror 302. The first laser beam may include three laser beams (e.g., blue laser, green laser, and red laser). For example, the first laser 100 may be used to emit blue and green laser light to the first mirror 301 and red laser light to the second mirror 302. The first mirror 301 may be used to direct blue and green laser light to the fly-eye lens 400, and the second mirror 302 may be used to direct red laser light to the fly-eye lens 400.

In the embodiment of the present application, the first lens 301 in the light combining lens group 300 may be a mirror for reflecting laser light of all colors, or may be a dichroic sheet for reflecting green laser light and blue laser light and transmitting laser light of other colors; the second mirror 302 may be a mirror for reflecting laser light of all colors, or may be a dichroic plate for reflecting red laser light and transmitting laser light of other colors.

In the present application, the polarization polarity of the blue laser light and the green laser light emitted by the first laser 100 is opposite to the polarization polarity of the red laser light. For example, the blue laser light and the green laser light are S-polarized light, and the red laser light is P-polarized light. To this end, the optical illumination system 000 may further include: the first polarization conversion member 800. The first polarization conversion member 800 may be located between the first laser 100 and the first lens 301, and the first polarization conversion member 800 may be configured to convert incident blue laser light and green laser light from S-polarized light to P-polarized light and emit the P-polarized light to the first lens 301, so that the polarization directions of the blue laser light and the green laser light entering the fly eye lens 400 are the same as the polarization direction of the red laser light. Therefore, the problem that color blocks exist in the formed projection picture due to different transmittance and reflectance efficiencies of the optical lens for different polarized light can be solved by adopting the laser with the uniform polarization direction to form the projection picture. Illustratively, the first polarization conversion member 800 may be a half-wave plate.

In a second case, please refer to fig. 9, where fig. 9 is a schematic structural diagram of another optical illumination system provided in the embodiment of the present application. The light combining lens assembly 300 may include: a first lens 301, a second lens 302 and a third lens 303 arranged in sequence along the X-axis direction. On a plane parallel to fly eye lens 400, the orthographic projection of first mirror 301, the orthographic projection of second mirror 302 and the orthographic projection of third mirror 303 at least partially coincide. In this way, the first laser 100 may be used to emit a first laser beam to the first mirror 301, the second mirror 302, and the third mirror 303. The first laser beam may include three laser beams (e.g., blue laser, green laser, and red laser). For example, the first laser 100 may be used to emit green laser light to the first mirror 301, and the first mirror 301 is used to reflect the green laser light to the fly-eye lens 400; the first laser 100 may be used to emit blue laser light to the second mirror 302, and the second mirror 302 is used to reflect the blue laser light to the fly-eye lens 400; the first laser 100 may be used to emit red laser light to the third mirror 303, and the third mirror 303 is used to reflect the red laser light toward the fly-eye lens 400.

In the embodiment of the present application, the first lens 301 in the light combining lens group 300 may be a mirror for reflecting light of all colors, or may be a dichroic sheet for reflecting green laser light and transmitting laser light of other colors; the second mirror 302 may be a dichroic plate for reflecting blue laser light and transmitting laser light of other colors; the third mirror 303 may be a dichroic plate for reflecting red laser light and transmitting laser light of other colors.

In the present application, the optical illumination system 000 may further include: the first polarization conversion member 800. The first polarization conversion member 800 may be located between the first laser 100 and the first lens 301 and the second lens 302, and the first polarization conversion member 800 may be configured to convert incident blue laser light and green laser light from S-polarized light to P-polarized light and then emit the light to the first lens 301 and the second lens 302, so that the polarization directions of the blue laser light and the green laser light incident to the fly-eye lens 400 are the same as the polarization direction of the red laser light. Illustratively, the first polarization conversion member 800 may be a half-wave plate.

In the embodiment of the present application, please refer to fig. 9, the optical illumination system 000 may further include: and a diffusion sheet 1000. The diffusion sheet 1000 may be positioned between the light combining assembly 200 and the fly-eye lens 400. The laser beam emitted from the light combining assembly 200 may be directed to the diffusion sheet 1000 along the X-axis direction, and the diffusion sheet 1000 may homogenize the incident laser beam and direct the homogenized laser beam to the fly-eye lens 400.

In summary, the present application provides an optical illumination system, including: the device comprises a first laser, a second laser, a light combining lens group, a fly-eye lens and a light valve. The optical illumination system can homogenize the laser beam by adopting a fly-eye lens, and the fly-eye lens consists of a glass substrate, a micro lens arranged on the light incident surface of the glass substrate and a micro lens arranged on the light emergent surface of the glass substrate. Therefore, the fly-eye lens is generally small in volume, effectively reducing the volume of the optical illumination system. Moreover, the optical illumination system does not need to be provided with a beam reduction lens group and a converging lens, so that the volume of the optical illumination system is further reduced. After the optical illumination system is integrated into the laser projection device, the volume of the laser projection device can be effectively reduced. In addition, the size of the microlens in the fly-eye lens may be determined according to the size of the spot of the laser unit and the size of the light valve. Therefore, the micro lens determined by the size of the light spot of the laser unit and the size of the light valve has better homogenization effect on the laser beams emitted by each laser unit.

Referring to fig. 10, fig. 10 is a schematic structural diagram of a laser projection apparatus according to an embodiment of the present disclosure. The laser projection apparatus may include: an optical illumination system 000 and a projection lens 001. The optical illumination system 000 may be the optical illumination system shown in fig. 2, 6, 8 or 9. Fig. 10 illustrates an example in which the laser projection apparatus includes the optical illumination system 000 shown in fig. 6.

The first laser beam emitted from the first laser 100 and the second laser beam emitted from the second laser 200 may be emitted to the fly-eye lens 400 along the X-axis direction in fig. 10, the fly-eye lens 400 may homogenize the emitted laser light and emit the homogenized laser light to the lens assembly 600, the lens assembly 600 may be configured to guide the laser beam emitted from the fly-eye lens 400 to the prism assembly 700, the prism assembly 700 may be configured to guide the laser beam to the light valve 500, the light valve 500 may be configured to modulate the laser beam and guide the modulated laser beam to the projection lens 001, and the projection lens 001 may project the emitted laser light to form a projection picture. The projection lens 001 may include a plurality of lenses (not shown in the figure), and the laser emitted from the light valve 500 may sequentially pass through the plurality of lenses in the projection lens 001 to be reflected to the screen, so as to realize the projection of the laser by the projection lens 001, and realize the display of the projection picture.

In this 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 "plurality" means two or more unless expressly limited otherwise.

The above description is intended to be exemplary only, and not to limit the present application, and any modifications, equivalents, improvements, etc. made within the spirit and scope of the present application are intended to be included therein.

Claims (10)

1. An optical illumination system, characterized in that the optical illumination system comprises: the device comprises a first laser, a second laser, a light combining lens group, a fly eye lens and a light valve;

the light combining lens group is positioned at the light emitting sides of the first laser and the second laser, the arrangement direction of the light combining lens group and the first laser is perpendicular to the arrangement direction of the light combining lens group and the fly eye lens, the arrangement direction of the second laser and the light combining lens group is parallel to the arrangement direction of the light combining lens group and the fly eye lens, and the second laser is positioned at one side of the light combining lens group away from the fly eye lens;

the first laser is used for emitting a first laser beam to the light combining lens group, the second laser is used for emitting a second laser beam to the light combining lens group, the light combining lens group is used for guiding the first laser beam and the second laser beam to the fly eye lens, and the fly eye lens is used for guiding the first laser beam and the second laser beam to the light valve;

the first laser and the second laser are respectively provided with a plurality of laser units, and the laser units are used for emitting laser light of at least two colors; the light incident surface of the fly-eye lens is provided with a plurality of micro lenses arranged in an array;

in a target direction, the width of the micro lens is determined based on the width of a light spot formed on the light incident surface by the laser emitted by the laser unit and the width of the light valve, and the target direction is a fast axis direction or a slow axis direction of the laser.

2. The optical illumination system according to claim 1, wherein the width d of the microlens in the target direction satisfies the following formula:

wherein D is the width of the light valve in the target direction; theta is a lens imaging angle; t is the width of the light spot of the laser unit in the target direction; k is a scaling factor greater than 0.

3. The optical illumination system according to claim 1 or 2, wherein the light spot of each laser unit overlaps with a region where at least two of the microlenses are located.

4. The optical illumination system of claim 3 wherein the width of the microlenses in the fast axis direction and the width in the slow axis direction are each in the range of 0.1 mm to 1 mm.

5. The optical illumination system according to claim 1 or 2, characterized in that the optical illumination system further comprises: a lens group and a prism group;

the lens group is positioned on one side of the fly eye lens, which is far away from the light combining lens group, and the prism group and the light valve are both positioned on one side of the lens group, which is far away from the fly eye lens;

the lens group is used for guiding a first laser beam emitted from the fly-eye lens to the prism group, the prism group is used for guiding the first laser beam to the light valve, and the light valve is used for modulating the first laser beam and guiding the first laser beam to the projection lens; the center point of the light-emitting surface of the fly-eye lens coincides with the focus of the lens group.

6. The optical illumination system according to claim 1 or 2, wherein the plurality of laser light emitting units of the first laser and the second laser each emit blue laser light, green laser light, and red laser light.

7. The optical illumination system of claim 6 wherein the first laser and the second laser are vertically aligned, and the light combiner comprises a first mirror and a second mirror, the first mirror and the second mirror being dichroic elements having different wavelength selective characteristics.

8. The optical illumination system of claim 6 wherein the first laser and the second laser are vertically aligned, and the light combining assembly comprises a first lens and a second lens, wherein the first lens and the second lens are polarizing elements with different polarization selection characteristics.

9. The optical illumination system of claim 8, wherein the plurality of laser unit arrays are arranged in four rows, and the four rows of laser units comprise: two rows of red laser units for emitting red laser light, one row of green laser units for emitting green laser light, and one row of blue laser units for emitting blue laser light.

10. A laser projection device, comprising: the optical illumination system and projection lens of any one of claims 1 to 9.

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