CN115509075A

CN115509075A - Projection equipment and projection system

Info

Publication number: CN115509075A
Application number: CN202211216165.3A
Authority: CN
Inventors: 颜珂
Original assignee: Qingdao Hisense Laser Display Co Ltd
Current assignee: Qingdao Hisense Laser Display Co Ltd
Priority date: 2022-09-30
Filing date: 2022-09-30
Publication date: 2022-12-23

Abstract

The invention discloses a projection device and a projection system, comprising: the laser light source comprises a plurality of red laser chips, a plurality of green laser chips and a plurality of blue laser chips, wherein the number of the green laser chips and the number of the blue laser chips are less than that of the red laser chips; at least one waveguide sheet, wherein one waveguide sheet is positioned at the light-emitting side of each green laser chip; the waveguide sheet comprises an incident part and an emergent part, wherein the incident part is used for guiding incident laser into the waveguide sheet, and the emergent part is used for guiding out the guided laser; and the width of the laser beam emitted by the light-emitting part is equal to that of the laser beam emitted by the red laser chip, so that the spot sizes of the blue laser and the green laser in the emitted light are the same as that of the red laser, the optical expansion amounts of the blue laser and the green laser are the same as that of the red laser, and the three colors of lasers are uniformly distributed after being combined.

Description

Projection equipment and projection system

Technical Field

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

Background

In the full-color laser display technology, red, green and blue lasers are generally used as light sources, so that the full-color laser display technology has the characteristics of high color gamut and high color saturation, can well restore colors in the real world, and realizes a good display effect. However, the quality of laser display images is affected due to the characteristics of high collimation, narrow spectrum and high coherence of laser, and the problem of laser speckle is also caused.

In the existing full-color laser display product, due to the requirements of color matching and laser power, the number of red lasers is generally required to be higher than that of blue and green lasers, so that the sizes of blue light and green light spots emitted by the blue and green lasers are different from the size of the light spot emitted by the red laser to a certain extent, and the problem of uneven emergent light exists; the red spot etendue is larger than the blue and green spots and further causes a problem in that the speckle of blue and green light is more serious than that of red light.

Disclosure of Invention

The invention provides a projection device and a projection system, which are used for solving the problem of uneven emission of red, green and blue laser in the conventional projection device.

In a first aspect, the present invention provides a projection device comprising:

the laser device comprises at least one laser light source, a plurality of laser chips and a plurality of laser chips, wherein the number of the laser chips is less than that of the laser chips;

at least one waveguide sheet, wherein one waveguide sheet is positioned at the light-emitting side of each green laser chip; the waveguide sheet comprises an incident part and an emergent part; the light inlet part is used for guiding incident laser into the waveguide sheet, and the light outlet part is used for guiding out the conducted laser; the width of the laser beam emitted by the light emitting part is equal to the width of the laser beam emitted by each red laser chip.

In some embodiments of the present invention, the waveguide sheet includes a light incident surface and a light emitting surface which are arranged in parallel, and the light incident portion and the light emitting portion are both located between the light incident surface and the light emitting surface; the laser light source is arranged opposite to the light incident surface of the waveguide sheet.

In some embodiments of the present invention, the light incident portion is a first reflective film, and the light emergent portion includes a transflective film and a second reflective film, wherein the transflective film is located between the first reflective film and the second reflective film;

the first reflection film, the transparent reflection film and the second reflection film are arranged in parallel and inclined at a set angle relative to the light incident surface of the waveguide sheet; the set angle meets the condition that the laser is subjected to total reflection in the waveguide sheet;

the distance between the transparent reflection film and the second reflection film is equal to the width of the laser beam emitted by each red laser chip.

In some embodiments of the present invention, the transflective film has a reflectivity of 50% and the transflective film has a transmissivity of 50%.

In some embodiments of the present invention, the light incident portion is a reflective film, the light emergent portion is a prism portion, the reflective film and the prism portion are separated by a set distance, and the prism portion is located on the light incident surface of the waveguide sheet;

the prism part comprises a plurality of strip prisms which are arranged in parallel, a transparent reflection film is arranged on the surface of one side, facing the reflection film, of the strip prisms, close to one side of the reflection film, and a reflection film is arranged on the surface of one side, facing the reflection film, of at least one strip prism, far away from one side of the reflection film;

the width of the prism part is equal to the width of the laser beam emitted by each red laser chip.

In some embodiments of the present invention, the projection apparatus includes only one waveguide sheet, and the waveguide sheet is located at the light-emitting side of each green laser chip;

or, the projection device includes two waveguide pieces, which are a first waveguide piece and a second waveguide piece respectively, where the first waveguide piece is located at each light-emitting side of the green laser chip, and the second waveguide piece is located at each light-emitting side of the blue laser chip.

In some embodiments of the invention, the projection device comprises one of the laser light sources, the laser light source comprising a plurality of red laser chips, a plurality of green laser chips, and a plurality of blue laser chips; the at least one waveguide sheet is located on the light emitting side of the laser light source.

In some embodiments of the invention, the projection device comprises two laser light sources, namely a first laser light source and a second laser light source;

the first laser light source comprises a plurality of red laser chips, and the second laser light source comprises a plurality of green laser chips and a plurality of blue laser chips; the at least one waveguide sheet is positioned on the light-emitting side of the second laser light source.

In some embodiments of the invention, the projection device further comprises:

the light combining lens group is positioned on the light emitting side of each laser light source and is used for combining red laser, green laser and blue laser;

the light uniformizing component is positioned on the light emergent side of the light combining lens group;

the shaping lens group is positioned on the light emitting side of the dodging component;

the light modulation component is positioned on the light emergent side of the shaping lens group and is used for modulating incident laser;

and the projection lens is positioned on the light emergent side of the light modulation component.

In a second aspect, the present invention provides a projection system comprising:

the projection device is any one of the projection devices;

and the projection screen is positioned on the light emergent side of the projection equipment.

The invention has the following beneficial effects:

the invention provides a projection device and a projection system, comprising: the laser light source comprises a plurality of red laser chips, a plurality of green laser chips and a plurality of blue laser chips, wherein the number of the green laser chips and the number of the blue laser chips are less than that of the red laser chips; at least one waveguide sheet, wherein one waveguide sheet is positioned at the light-emitting side of each green laser chip; the waveguide sheet comprises an incident part and an emergent part, wherein the incident part is used for guiding incident laser into the waveguide sheet, and the emergent part is used for guiding out the guided laser; and the width of the laser beam emitted by the light-emitting part is equal to that of the laser beam emitted by the red laser chip, so that the spot sizes of the blue laser and the green laser in the emitted light are the same as that of the red laser, the optical expansion amounts of the blue laser and the green laser are the same as that of the red laser, and the three colors of lasers are uniformly distributed after being combined.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments of the present invention will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic diagram of a light combination scheme of a three-color laser light source in the prior art;

FIG. 2 is a schematic view of an array type waveguide sheet;

FIG. 3 is a schematic view of a sawtooth waveguide sheet;

fig. 4 is a schematic plan view of a laser light source according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of a projection apparatus according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of an optical path provided by an embodiment of the present invention;

FIG. 7 is a second schematic diagram of the optical path provided by the embodiment of the present invention;

fig. 8 is a second schematic structural diagram of a projection apparatus according to an embodiment of the invention;

FIG. 9 is a third schematic diagram of an optical path provided by the embodiment of the present invention;

FIG. 10 is a fourth schematic diagram of the optical path provided by the embodiment of the present invention;

FIG. 11 is a fifth schematic diagram of an optical path provided by the embodiment of the present invention;

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

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, the present invention is further described with reference to the accompanying drawings and examples. Example embodiments may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and thus their repetitive description will be omitted. The words expressing the position and direction described in the present invention are illustrated in the accompanying drawings, but may be changed as required and still be within the scope of the present invention. The drawings of the present invention are for illustrative purposes only and do not represent true scale.

In a projection device, a light source is a main reason influencing projection quality, and because laser is a light source with the highest color purity at present, the laser with the three primary colors of red, green and blue can be restored to colors close to the real world to the greatest extent after being mixed and toned, so that the laser light source has unique advantages which are not possessed by the traditional light source, and therefore, a full-color laser display technology using the laser with the three primary colors of red, green and blue as the light source becomes a great development trend in the projection field at present.

In the full-color laser display technology, a certain amount of red laser, green laser and blue laser are proportioned and combined to form an image directly, so that the full-color laser display technology has the advantages of high color gamut, high contrast and good color performance, and can realize a good projection effect when being applied to projection equipment. However, due to the characteristics of high collimation, narrow spectrum and high coherence of laser, bright spots and dark spots which are randomly distributed in a display image, namely, the laser speckle phenomenon, can seriously affect the definition and resolution of the display image, and reduce the display quality.

In the current full-color laser display product, because of the requirements of color matching and laser power, the number of red lasers is generally required to be higher than the number of blue and green lasers, so that the beam widths of blue laser emitted by the blue laser and green laser emitted by the green laser and red laser emitted by the red laser are different, and the problem of uneven emergent light exists after light combination.

Further, the product of the spot size and the divergence angle of the laser determines the etendue of the laser beam, i.e., the smaller the beam size of the laser, the smaller the etendue of the laser beam, and the more severe the laser speckle phenomenon due to the smaller etendue, the etendue of the red laser in the current full-color laser display product is greater than that of the blue laser and the green laser, and the problem that the blue laser and the green laser speckle are more obvious than the red laser is also brought.

Fig. 1 is a schematic diagram of a light combination scheme of a three-color laser light source in the prior art.

As shown in fig. 1, in the currently used laser light source, the number ratio of red, green and blue laser chips is generally 2. The first dichroic filter 05 may reflect blue laser light and transmit green laser light, and the second dichroic filter 06 may reflect red laser light, transmit blue laser light, and green laser light.

The green laser emitted by the green laser chip 01 is incident on the reflector plate 04, reflected to the first dichroic plate 05, transmitted by the first dichroic plate 05 and the second dichroic plate 06 in sequence and then incident on the lens 07; blue laser emitted by the blue laser chip 02 enters the first dichroic filter 05, is reflected to the second dichroic filter 06, and is transmitted to the lens 07 by the second dichroic filter 06; the red laser emitted by the red laser chip 03 is incident on the second dichroic sheet 06 and then reflected to the lens 07, and the red, green and blue lasers are combined by the lens 07 and then emitted.

However, since the number of the red laser chips in the laser light source is greater than the number of the blue laser chips and the green laser chips, the width of the red laser beam incident to the lens is greater than the widths of the green laser beam and the blue laser beam, the size of each color beam cannot be changed by using the scheme of combining the light by the dichroic sheet, and finally, the emergent light combined by the lens 07 is not uniform, which affects the effect of projection display.

In view of this, an embodiment of the present invention provides a projection apparatus, so as to solve the problem of uneven light emission in the projection apparatus.

The waveguide sheet is used in the embodiment of the present invention to achieve the effect of expanding the light beam, and is specifically based on the principle of the array type waveguide sheet and the sawtooth-shaped waveguide sheet. The waveguide sheet is essentially a transparent substrate with high refractive index, light beams emitted by a light source are coupled into the substrate from the side edge of the substrate through a specific structure, are totally reflected and propagated in the substrate, and are coupled and emitted out through the specific structure after being propagated to a certain position.

Fig. 2 is a schematic view of the principle of the array type waveguide sheet.

As shown in fig. 2, the coupling-in end of the arrayed waveguide sheet a may include a coupling-in end reflective film a1, and the coupling-out end may include at least one layer of a transflective film a2 and a coupling-out end reflective film a3. The light beam incident to the coupling end of the array type waveguide sheet A is reflected by the coupling end reflection film a1 and then is totally reflected and propagated in the array type waveguide sheet A for multiple times, when the light beam passes through each transflective film a2, the transflective film a2 reflects and couples a part of the light beam out of the array type waveguide sheet A, and transmits the other part of the light beam to the next transflective film, until the light beam is propagated to the coupling end reflection film a3 at the coupling end of the array type waveguide sheet A, the coupling end reflection film a3 totally reflects the rest of the light beam out of the array type waveguide sheet A.

The light beams in the array type waveguide sheet can be emitted in batches through the plurality of film layers arranged in the array type waveguide sheet, so that the effect of expanding the light beams is achieved, further, the number and the positions of the transparent reflection films in the array type waveguide sheet are adjusted, the size of the light beams can be flexibly controlled, the reflectivity and the transmissivity of each transparent reflection film are adjusted, the light beams are reflected in the array type waveguide sheet for multiple times, and the emergent light can be adjusted to be more uniform.

Fig. 3 is a schematic view of a saw-tooth waveguide sheet.

As shown in fig. 3, the sawtooth waveguide sheet B may include a reflection film B1 at a coupling end and a prism portion B2 at a coupling end, a transparent reflection film or a reflection film may be disposed on each surface of the prism portion B2, and the number of transparent reflection films and reflection films may be set according to actual needs. The light beam is incident from the reflecting film B1, reflected by the reflecting film B1 and then totally reflected and propagated in the sawtooth-shaped waveguide sheet B for multiple times, when the light beam passes through each transflective film on the prism part B2, a part of the light beam is reflected out of the sawtooth-shaped waveguide sheet B, the other part of the light beam is transmitted to the next transflective film, and when the light beam is propagated to the reflecting film on the prism part B2, the light beam can be reflected out of the sawtooth-shaped waveguide sheet B.

The transmission and reflection film and the reflection film are arranged in the sawtooth-shaped waveguide sheet B, so that the light spots of the emergent light can be expanded to be the same as the width of the prism part, and the function of homogenizing the light beam is achieved.

The principle of the array type waveguide sheet and the sawtooth-shaped waveguide sheet is applied to projection equipment, so that the laser beams with different colors emitted by the laser source can be uniformly distributed.

The projection device provided by the embodiment of the invention can comprise at least one laser light source and at least one waveguide sheet.

Fig. 4 is a schematic plan view of a laser light source according to an embodiment of the present invention.

As shown in fig. 4, the laser light source 40 includes a plurality of red laser chips 403, a plurality of green laser chips 401, and a plurality of blue laser chips 402, wherein the number of green laser chips 401 and the number of blue laser chips 402 are less than the number of red laser chips 403. The red laser chips 403, the green laser chips 401 and the blue laser chips 402 are arranged in an array.

In a specific implementation, the laser light source 40 may employ a laser or a laser array, and taking fig. 4 as an example, the current MCL laser generally has 4 rows and 7 columns of laser chips, and in an embodiment of the present invention, the laser may include 2 rows and 7 columns of

red laser chips

403,1 rows and 7 columns of

green laser chips

401, and 1 row and 7 columns of blue laser chips 402.

In practical applications, other numbers of laser chips and lasers may be used and arranged in other arrangement manners, and the embodiment of the present invention is only used for illustration and is not limited to the specific numbers and arrangement manners of the laser chips and the lasers.

Since the ratio of the number of red, green and blue laser chips in the currently used laser is generally 2.

The at least one waveguide sheet is positioned on the light emitting side of each green laser chip, each waveguide sheet comprises a light inlet part and a light outlet part, the light inlet part is used for guiding incident laser into the waveguide sheet, the light outlet part is used for guiding the transmitted laser out, and the width of the laser beam emitted by the light outlet part is equal to that of the laser beam emitted by each red laser chip.

In a specific implementation, the waveguide sheet may be made of a material with low optical transparency and transmission loss, such as glass, silica, lithium niobate, or a polymer material, and a film layer with a reflection or transmission function may be formed in the light incident portion and the light exiting portion of the waveguide sheet, so that the light incident into the waveguide sheet propagates through the waveguide sheet according to a set path.

Fig. 5 is a schematic structural diagram of a projection apparatus according to an embodiment of the present invention.

As shown in fig. 5, the laser light source 40 includes a green laser chip 401, a blue laser chip 402, and a red laser chip 403. The waveguide sheet 10 includes a light incident surface I and a light emitting surface O disposed in parallel, and the light incident portion 20 and the light emitting portion 30 of the waveguide sheet 10 are both located between the light incident surface I and the light emitting surface O. The laser light source 40 is disposed opposite to the light incident surface I of the waveguide sheet 10.

In the embodiment of the present invention, the projection apparatus may include only one waveguide sheet 10, and the waveguide sheet 10 is located on the light emitting side of each green laser chip 401, and the waveguide sheet 10 may expand the beam width of the green laser beam emitted from the green laser chip 401, so that the width of the green laser beam emitted from the light emitting portion 30 of the waveguide sheet 10 is equal to the width of the red laser beam emitted from each red laser chip 403. In specific implementation, the waveguide sheet 10 may be an array type waveguide sheet or a sawtooth type waveguide sheet.

Because human eyes are insensitive to blue light, emergent light can be more uniform only by enabling the beam widths of the green laser beam and the red laser beam to be the same, the optical expansion amount of the green laser beam is increased, the optical expansion amount of the green laser beam is enabled to be the same as that of the red laser beam, the speckle phenomenon of the green laser beam can be reduced, and therefore the good projection display effect can be achieved with low cost.

The projection apparatus in the embodiment of the present invention may further include a light combining lens set 50, where the light combining lens set 50 is located on the light emitting side of the laser light source 40, and is configured to combine the red laser light, the green laser light, and the blue laser light, and the combined light beam has better uniformity. In a specific implementation, the light combining mirror group 50 may be formed by at least one reflecting mirror, at least one dichroic mirror, and the like, and may be set according to specific requirements.

The light uniformizing component 60 may be disposed on the light emitting side of the light combining lens assembly 50 for further homogenizing the light combined by the light combining lens assembly 50, so as to make the laser energy distribution more uniform and improve the laser speckle. In specific implementation, a light guide, a fly-eye lens, or the like may be used as the light uniformizing member 60.

The light combining lens assembly 50 combines the three colors of lasers emitted from the laser light source 40, and the size of the combined laser spot is generally large, so the focusing lens assembly 500 can be disposed on the light emitting side of the light combining lens assembly 50 for focusing and converging the laser beams, so that more light can be incident into the light uniformizing element 60.

Fig. 6 is a schematic diagram of an optical path according to an embodiment of the present invention.

As shown in fig. 6, the waveguide sheet 10 according to the embodiment of the present invention may be an array type waveguide sheet.

Specifically, the light incident portion of the waveguide sheet 10 may be the first reflective film 21, the light emergent portion may include the transflective film 31 and the second reflective film 32, and the transflective film 31 is located between the first reflective film 21 and the second reflective film 32. The first reflective film 21, the transflective film 31, and the second reflective film 32 are disposed in parallel with each other, and are inclined with respect to the light incident surface I of the waveguide sheet 10 by a set angle that satisfies a condition for reflecting the incident laser light and causing total reflection of the laser light in the waveguide sheet 10. In practical implementation, the transmittance and reflectance of the transflective film 31 with respect to incident light can be changed by coating the transflective film 31 with a film, and the wavelength of light that can be transmitted and reflected can be changed by coating the second reflective film 32 with a film, in the projection apparatus shown in fig. 6, the transflective film 31 can transmit a part of green laser light and reflect a part of green laser light, and can completely transmit red laser light, and the second reflective film 32 can transmit red laser light and reflect green laser light, and at this time, the second reflective film 32 corresponds to a dichroic mirror.

As shown in fig. 6, the green laser emitted from the green laser chip 401 is guided into the optical waveguide 10 by the first reflective film 21, because the inclination angle of the first reflective film 21 relative to the light incident surface I satisfies the total reflection condition, after the first reflective film 21 reflects the green laser onto the light incident surface I of the waveguide sheet 10, the green laser may be reflected by the light incident surface I and the light emitting surface O multiple times in the waveguide sheet 10 and then incident onto the transflective film 31, a part of the light reflected by the transflective film 31 of the green laser is guided out of the optical waveguide 10, and a part of the light transmitted by the transflective film 31 of the green laser continues to propagate in the waveguide sheet 10 to the second reflective film 32 and then is totally reflected by the second reflective film 32 and guided out of the waveguide sheet 10.

The light combining lens set 50 in the embodiment of the present invention may include a first light combining lens 51 and a second light combining lens 52, where the first light combining lens 51 has an effect of reflecting blue light, and the second light combining lens 52 has an effect of reflecting red light, green light, and transmitting blue light. The first light combining mirror 51 and the second light combining mirror 52 are disposed in parallel, and they may form a set angle with the waveguide sheet 10.

The green laser light is guided out of the waveguide sheet 10 and then reflected by the second beam combiner 52 toward the focusing lens 500; blue laser emitted from the blue laser chip 402 is directly transmitted by the waveguide sheet 10 and then enters the first light combining mirror 51, is reflected by the first light combining mirror 51 to the second light combining mirror 52, is transmitted by the second light combining mirror 52 and then enters the focusing lens 500; the red laser emitted from the red laser chip 403 is transmitted by the waveguide sheet 10, then enters the second light combining mirror 52, and is reflected by the second light combining mirror 52 toward the focusing lens 500; the three-color laser light of red, green, and blue incident to the focusing lens 500 is focused by the focusing lens 500.

In the embodiment of the present invention, the transflective film 31 and the second reflective film 32 are respectively disposed on the light-emitting sides of two rows of red laser chips 403, and since the green laser is twice guided out of the waveguide sheet 10 by the transflective film 31 and the second reflective film 32, the width of the green laser beam emitted from the waveguide sheet 10 is equal to the distance between the transflective film 31 and the second reflective film 32. Moreover, the transflective film 31 and the second reflective film 32 can both transmit the red laser, so that the width of the red laser beam emitted from the red laser chip 403 is equal to the distance between the transflective film 31 and the second reflective film 32, so that the width of the green laser beam is equal to the width of the red laser beam, the emitted light is more uniform, the etendue of the green laser beam is expanded to be equal to the etendue of the red laser beam, and the speckle phenomenon of the green laser is reduced.

In practical implementation, the transmittance and the reflectance of the transflective film 31 may be changed according to the design requirement of the projection apparatus, and in some embodiments of the present invention, the transmittance of the transflective film 31 may be 50%, and the reflectance of the transflective film 31 may be 50%, which may equalize the light energy of the green laser emitted from the transflective film 31 and the second reflective film 32, so that the light intensity distribution of the emitted green laser beam is more uniform.

Fig. 7 is a second schematic diagram of the optical path provided by the embodiment of the invention.

As shown in fig. 7, the waveguide sheet 10 according to the embodiment of the present invention may be a zigzag waveguide sheet.

Specifically, the light incident portion of the waveguide sheet 10 may be the reflection film 22, the light emergent portion may be the prism portion 33, the reflection film 22 is spaced from the prism portion 33 by a predetermined distance, and the prism portion 33 is located on the light incident surface I of the waveguide sheet 10. The prism portion 33 may include a plurality of parallel strip prisms N, a transparent reflective film is disposed on a surface of one side of the plurality of strip prisms N facing the reflective film 22, the side being close to the reflective film 22, and a reflective film is disposed on a surface of one side of at least one strip prism N facing the reflective film 22, the side being far away from the reflective film 22. In a specific implementation, a reflective film may be disposed on a surface of the strip prism N farthest from the reflective film 22 facing the reflective film 22, and the reflective film may reflect all the light propagating to the position in the waveguide sheet 10 out of the waveguide sheet 10, so as to avoid loss of the light.

As shown in fig. 7, the green laser emitted from the green laser chip 401 is guided into the waveguide sheet 10 by the reflection film 22, and then reflected by the reflection film 22 to the light incident surface I of the waveguide sheet 10, the green laser can be reflected by the light incident surface I and the light emitting surface O in the waveguide sheet 10 for multiple times and then incident to the prism portion 33, the green laser can be partially transmitted and partially reflected when passing through the transflective film on each stripe prism N, the transmitted light continues to propagate to the next stripe prism N, the reflected light is guided out of the waveguide sheet 10, and the green laser is totally reflected out of the optical waveguide 10 by the reflection film N1 after the above processes are repeated for multiple times.

The green laser emitted from the green laser chip 401 is emitted in the waveguide sheet 10 for multiple times, and finally the light beam width of the light-emitting waveguide 10 is equal to the width of the prism part 33, and in the embodiment of the invention, the width of the prism part 33 is set to be equal to the width of the laser beam emitted from each red laser chip 403, so that the light beam widths of the green laser and the red laser are equal, the emitted light of the green laser and the red laser after being combined by the light combining lens 50 is more uniform, meanwhile, the optical expansion amount of the green laser beam is expanded to be equal to that of the red laser beam, and the speckle phenomenon of the green laser is reduced.

Fig. 8 is a second schematic structural diagram of a projection apparatus according to an embodiment of the invention.

As shown in fig. 8, in the embodiment of the present invention, the projection apparatus may include two waveguide sheets, i.e., a first waveguide sheet 101 and a second waveguide sheet 102, wherein the first waveguide sheet 101 is located on the light-emitting side of each green laser chip 401, and the second waveguide sheet 102 is located on the light-emitting side of each blue laser chip 402. The first waveguide sheet 101 may expand the width of the green laser beam emitted from the green laser chip 401, and the second waveguide sheet 20 may expand the width of the blue laser beam emitted from the blue laser chip 402 such that the width of the green laser beam emitted from the first waveguide sheet 101, the width of the blue laser beam emitted from the second waveguide sheet 102, and the width of the red laser beam emitted from each red laser chip 403 are equal to each other.

The scheme of arranging the two waveguide sheets in the projection device can be used under the condition that the number of blue laser chips in a laser light source is small, the widths of blue and green laser beams are enlarged to be the same as the width of a red laser beam, emergent light can be distributed uniformly, and the problem that the color temperature and the color condition of a display picture are abnormal due to the fact that the width of the blue laser beam is small can be solved. The optical expansion of the blue laser and the green laser is increased to be the same as that of the red laser, and the difference between the speckle phenomenon of the blue laser and the speckle phenomenon of the green laser and the speckle phenomenon of the red laser is reduced.

In specific implementation, the first waveguide sheet 101 and the second waveguide sheet 102 may both be array-type waveguide sheets; alternatively, the first waveguide sheet 101 and the second waveguide sheet 102 both employ saw-toothed waveguide sheets; alternatively, the first waveguide sheet 101 and the second waveguide sheet 102 may be an array-type waveguide sheet and a sawtooth-shaped waveguide sheet, respectively, and both the effects of expanding the beam widths of the blue laser beam and the green laser beam may be achieved. The following embodiments are described taking as an example a case where the first waveguide sheet 101 and the second waveguide sheet 102 each employ an arrayed waveguide sheet.

Fig. 9 is a third schematic diagram of an optical path according to an embodiment of the present invention.

As shown in fig. 9, the light incident portion of the first waveguide sheet 101 may be a third reflective film 211 disposed on the light emitting side of the green laser chip 401, the light emergent portion of the first waveguide sheet 101 may include a first transparent reflective film 311 and a fourth reflective film 321, the first transparent reflective film 311 is disposed between the third reflective film 211 and the fourth reflective film 321, the third reflective film 211, the first transparent reflective film 311, and the fourth reflective film 321 are disposed in parallel, and the three are inclined with respect to the light incident surface of the first waveguide sheet 101 by a set angle, which satisfies the condition that the laser is totally reflected in the first waveguide sheet 101.

The light incident portion of the second waveguide sheet 102 may be a fifth reflective film 212 disposed on the light emitting side of the blue laser chip 402, the light emergent portion of the second waveguide sheet 102 may include a second transflective film 312 and a sixth reflective film 322, the second transflective film 312 is disposed between the fifth reflective film 212 and the sixth reflective film 322, and the fifth reflective film 212, the second transflective film 312 and the sixth reflective film 322 are disposed in parallel and are inclined with respect to the light incident surface of the second waveguide sheet 102 by a predetermined angle that satisfies a condition that the laser is totally reflected in the second waveguide sheet 102.

The distance between the first transflective film 311 and the fourth reflective film 321, and the distance between the second transflective film 312 and the sixth reflective film 322 are all equal to the width of the laser beam emitted from each red laser chip 403. In a specific implementation, the first transflective film 311 and the second transflective film 312 may be disposed in parallel, and the fourth reflective film 321 and the sixth reflective film 322 may be disposed in parallel.

The green laser beam emitted from the green laser chip 401 is reflected by the third reflective film 211, then totally reflected in the first waveguide sheet 101 for multiple times and then incident on the first transflective film 311, and then the green laser beam is partially transmitted and partially reflected, and the transmitted light beam is continuously transmitted to the fourth reflective film 321 in the first waveguide sheet 101 and totally reflected out of the first waveguide sheet 101 by the fourth reflective film 321, so that the width of the green laser beam guided out of the first waveguide sheet 101 is equal to the width of the red laser beam.

The blue laser beam emitted from the blue laser chip 402 is reflected by the fifth reflective film 212, then totally reflected in the second waveguide sheet 102 for multiple times and then incident on the second transflective film 312, and then the blue laser beam is partially transmitted and partially reflected, and the transmitted part of the light beam continues to propagate in the second waveguide sheet 102 to the sixth reflective film 322 and is totally reflected out of the second waveguide sheet 102 by the sixth reflective film 322, so that the width of the blue laser beam led out from the second waveguide sheet 102 is equal to the width of the red laser beam.

The green laser beam guided out from the first waveguide sheet 101, the blue laser beam guided out from the second waveguide sheet 102, and the red laser beam emitted from each red laser chip 403 are directly incident on the focusing lens 500.

Set up two waveguide pieces in projection equipment, can make the light beam width of red, green, blue three-colour laser equal for emergent light colour distributes evenly, and only sets up a focusing lens and is used for focusing light, has left out and has closed the optical lens group, is favorable to simplifying projection equipment's inner structure, realizes low-cost and lightweight design.

Fig. 10 is a fourth schematic diagram of optical paths provided by the embodiment of the present invention.

As shown in fig. 10, the light combining lens assembly in the embodiment of the present invention may include a first light combining lens 51, and the first light combining lens 51 may be configured to reflect the green laser light emitted from the first waveguide sheet 101, the blue laser light emitted from the second waveguide sheet 102, and the red laser light emitted from the red laser chip 403 to the same direction to combine the light and to enter the focusing lens 500, so that the projection image may be turned, and the projection apparatus may be applied to more real scenes.

Referring to fig. 5 to 10, in some embodiments of the present invention, the projection apparatus may include one laser light source 40, the laser light source 40 may include a plurality of red laser chips 403, a plurality of green laser chips 401, and a plurality of blue laser chips 402, and the at least one optical waveguide is located on the light emitting side of the laser light source 40.

Fig. 11 is a fifth schematic view of the optical path provided by the embodiment of the invention.

As shown in fig. 11, in other embodiments of the present invention, the projection apparatus may include two laser light sources, namely a first laser light source 41 and a second laser light source 42, wherein the first laser light source 41 includes a red laser chip 403, the second laser light source 42 includes a green laser chip 401 and a blue laser chip 402, and the first waveguide sheet 101 and the second waveguide sheet 102 are located on the light emitting side of the second laser light source 42. In specific implementation, the number of the red laser chip 403, the green laser chip 401, the blue laser chip 402 and the waveguide sheet may be multiple, and is not limited herein.

The light combining lens assembly in the embodiment of the present invention may include a third light combining lens 53, where the third light combining lens 53 has functions of reflecting blue light, reflecting green light, and transmitting red light.

The red laser beam emitted from the red laser chip 403 in the first laser source 41 is transmitted by the third light combining mirror 53 and then enters the focusing lens 500; the green laser beam emitted from the green laser chip 401 in the second laser source 42 is expanded to have the same width as the red laser beam by the first waveguide sheet 101, the blue laser beam emitted from the blue laser chip 402 in the second laser source 42 is expanded to have the same width as the red laser beam by the second waveguide sheet 102, both the green laser beam and the blue laser beam are reflected to the focusing lens 500 by the third light combining mirror 53, and the focusing lens 500 then polymerizes the red, green and blue laser beams.

The scheme of including two laser light sources in the projection apparatus may also be used in a scene where the laser light sources include 2 rows and 7 columns of

red laser chips

403,1, 7 rows and 7 columns of

green laser chips

401, and 1 row and 7 columns of blue laser chips 402.

Referring to fig. 5 and 8, the embodiment of the present invention may further include a shaping lens group 70, a light modulation component 80, and a projection lens 90.

The shaping lens set 70 may be formed by combining a plurality of lenses, the specific structure of the lens may be obtained by optical design according to actual requirements, in a specific implementation, the shaping lens set 70 may include at least one lens, and the specific structure and the number of the lenses of the shaping lens set 70 are not limited herein. The shaping lens group 70 is located at the light-emitting side of the dodging component 60, and the shaping lens group 70 can collimate the laser light and make the laser light spot incident on the light modulation component 80 at a proper angle.

The light modulation component 80 is located on the light exit side of the shaping lens group 70, and may be configured to modulate incident laser light, in a specific implementation, a Digital Micromirror Device (DMD) may be used as the light modulation component 80, the surface of the DMD includes a plurality of tiny mirrors, each tiny mirror may be separately driven to deflect, and by controlling the deflection angle and the deflection time of the DMD, the brightness of the reflected light may be modulated, and the modulated reflected light is incident on the projection lens 90.

The projection lens 90 is located on the light exit side of the light modulation component 80, the specific structure of the projection lens can be obtained by optical design according to actual requirements, and the projection lens 90 can be an ultra-short-focus projection lens, which is not limited herein. The projection lens 90 may be used to emit and image the laser light modulated by the light modulation part 80.

Based on the same inventive concept, the embodiment of the present invention further provides a projection system, as shown in fig. 12, the projection system includes a projection apparatus 1 and a projection screen 2.

Projection screen 2 is located projection equipment 1's light-emitting side, and the spectator is towards projection screen 2, and projection equipment 1 outgoing projection light, projection light incides projection screen 2, incides the people's eye through projection screen 2's reflection to make spectator watch the projection image. When the projection device 1 is specifically implemented, any one of the projection devices in the above embodiments may be adopted, and the three-color laser emitted by the projection device has the characteristics of uniform light emission and few speckles, so that a projection image projected to the projection screen by the projection device may have good contrast and definition.

It is worth mentioning that the embodiment of the invention can also be applied to the field of laser illumination, and beam expansion of laser beams can be realized by arranging at least one optical waveguide, so that uniform white light can be obtained after light combination of red, green and blue laser beams as a light source of the illumination device, and a good illumination effect is realized.

According to the first invention concept, a waveguide sheet is arranged on the light emitting side of each green laser chip of a laser light source, the green laser is emitted from the waveguide sheet twice by arranging the transmitting and reflecting film and the reflecting film with a set distance in the waveguide sheet, and the specific distance is equal to the width of the red laser beam emitted from the red laser chip, so that the green laser beam can be expanded to be equal to the width of the red laser beam, and when the number of the blue laser chips is not greatly different from that of the green laser chips, the three-color laser can be emitted uniformly.

According to the second inventive concept, a waveguide sheet is disposed on the light emitting side of each green laser chip of the laser light source, a reflection film and a prism portion including a plurality of strip prisms are disposed in the waveguide sheet, the prism portion has a width equal to that of a red laser beam emitted from the red laser chip, a transparent reflection film is disposed on the surface of one side of each strip prism facing the reflection film, and a reflection film is disposed on the surface of one side of at least one strip prism facing the reflection film, away from the reflection film, so that the green laser beam is emitted from the waveguide sheet for a plurality of times, the green laser beam can be expanded to have a width equal to that of the red laser beam, and the three-color laser beam can be emitted uniformly when the number of blue laser chips is not much different from the number of green laser chips.

According to the third inventive concept, the first waveguide sheet is arranged on the light-emitting side of each green laser chip, the second waveguide sheet is arranged on the light-emitting side of each blue laser chip, the widths of the green laser beams and the blue laser beams can be expanded to be equal to the width of the red laser beams emitted by each red laser chip, the red, green and blue lasers can be emitted uniformly, the difference of speckle phenomena of the blue laser, the green laser and the red laser is reduced, and meanwhile, the problems of abnormal color temperature and color cast of a display picture can be avoided when the number of the blue laser chips is small.

According to the fourth inventive concept, the light-emitting side of each optical waveguide is provided with the light combining lens group, the light uniformizing part and the like, so that the red, green and blue lasers can be combined to achieve uniform white light, and the light-emitting device can be applied to the field of laser illumination.

According to the fifth inventive concept, by using one or two laser light sources, the diversified design of the internal structure of the projection device can be realized, and the laser light sources are respectively suitable for the situations of different numbers of three-color laser chips in the laser light sources.

While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. A projection device, comprising:

the laser system comprises at least one laser light source, a plurality of light source modules and a plurality of light source modules, wherein the at least one laser light source comprises a plurality of red laser chips, a plurality of green laser chips and a plurality of blue laser chips, and the number of the green laser chips and the number of the blue laser chips are both less than that of the red laser chips;

at least one waveguide plate, wherein one waveguide plate is positioned at the light-emitting side of each green laser chip; the waveguide sheet comprises an incident part and an emergent part; the light inlet part is used for guiding incident laser into the waveguide sheet, and the light outlet part is used for guiding out the conducted laser; the width of the laser beam emitted by the light emitting part is equal to the width of the laser beam emitted by each red laser chip.

2. The projection apparatus according to claim 1, wherein the waveguide sheet includes a light incident surface and a light emitting surface arranged in parallel, and the light incident portion and the light emitting portion are both located between the light incident surface and the light emitting surface; the laser light source is arranged opposite to the light incident surface of the waveguide sheet.

3. The projection apparatus according to claim 2, wherein the light incident portion is a first reflective film, and the light exit portion includes a transflective film and a second reflective film, the transflective film being located between the first reflective film and the second reflective film;

4. The projection device of claim 3, wherein the transflective film has a reflectivity of 50% and a transmissivity of 50%.

5. The projection apparatus according to claim 2, wherein the light incident portion is a reflection film, the light exiting portion is a prism portion, the reflection film is spaced from the prism portion by a set distance, and the prism portion is located on the light incident surface of the waveguide sheet;

the prism part comprises a plurality of strip prisms which are arranged in parallel, a transparent reflection film is arranged on the surface of one side, facing the reflection film, of the strip prisms close to one side of the reflection film, and a reflection film is arranged on the surface of one side, facing the reflection film, of at least one strip prism far away from one side of the reflection film;

6. The projection device of claim 1, wherein the projection device includes only one of the waveguide sheets, the waveguide sheet being located on an output side of each of the green laser chips;

7. The projection device of claim 6, wherein the projection device includes one of the laser light sources, the laser light source including a plurality of red laser chips, a plurality of green laser chips, and a plurality of blue laser chips; the at least one waveguide sheet is located on the light emitting side of the laser light source.

8. The projection device of claim 6, wherein the projection device includes two of the laser light sources, a first laser light source and a second laser light source;

9. The projection device of claim 7 or 8, wherein the projection device further comprises:

the light homogenizing component is positioned on the light emitting side of the light combining lens group;

and the projection lens is positioned on the light emitting side of the light modulation component.

10. A projection system, comprising:

a projection device according to any one of claims 1 to 9;