CN113946092A

CN113946092A - Projection system

Info

Publication number: CN113946092A
Application number: CN202110881856.4A
Authority: CN
Inventors: 杨雨桦; 朱立全; 姚昞晖; 叶成伟; 田大伟; 张金; 尹亚铁
Original assignee: Hefei Full Color Light Display Technology Co ltd
Current assignee: Hefei Full Color Light Display Technology Co ltd
Priority date: 2021-08-02
Filing date: 2021-08-02
Publication date: 2022-01-18
Also published as: CN117008404A

Abstract

The application discloses projection system, this projection system includes colour mixture light source module, closes and restraints module and even light module, wherein, colour mixture light source module is used for providing three primary colors LED light and yellow laser light, three primary colors LED light and yellow laser light form colour mixture light after closing the beam module through closing, colour mixture light is through even light of even light module and plastic processing back, obtain projection light and carry out the projection, utilize yellow laser light to compensate the problem that three primary colors LED light can't fully traverse at yellow part in this system, the poor problem of projection system color rendering capability has been solved, only adopted a laser light in this system simultaneously, the problem that the heat dissipation capacity that has avoided all adopting laser light source as working light and lead to is big has been avoided.

Description

Projection system

Technical Field

The present application relates to the field of optical optoelectronics, and more particularly, to a projection system.

Background

Projection systems, i.e. optical systems that illuminate objects and image them on a projection screen, have the ultimate goal of realistically reproducing the colors and various scenes of nature that can be seen by the human eye. The Light source is mainly divided into three types, namely a bulb, an LED (Light-Emitting Diode) and laser projection according to different Light sources, and with the development of display technology, a projection technology taking the LED and the laser as Light sources is distinguished.

However, the current projection systems using LEDs or lasers as light sources have problems of poor color rendering capability or large heat dissipation.

Disclosure of Invention

In order to solve the above technical problem, the present application provides a projection system to solve the problem of poor color rendering capability or large heat dissipation capacity of the projection system.

In order to achieve the technical purpose, the embodiment of the application provides the following technical scheme:

a projection system, comprising: the device comprises a color mixing light source module, a beam combining module and a light homogenizing module; wherein the content of the first and second substances,

the color mixing light source module is used for providing three primary colors LED light and yellow laser light;

the beam combining module is used for combining the three primary colors of LED light into a first combined light beam and combining the first combined light beam and the yellow laser light into a mixed color light beam;

the dodging module is used for dodging and shaping the mixed color light to obtain projection light.

Optionally, the color mixing light source module includes: an LED light source unit and a laser light source unit; wherein the content of the first and second substances,

the LED light source unit comprises a plurality of LEDs, and the LEDs at least comprise a first LED, a second LED and a third LED, wherein the first LED is used for emitting red light, the second LED is used for emitting green light, and the third LED is used for emitting blue light;

the laser light source unit comprises at least one laser, and the laser is used for emitting yellow laser light.

Optionally, the method further includes: an optical modulation module;

the light modulation module includes: a circuit board and a first signal controller; wherein the content of the first and second substances,

the circuit board is used for bearing the LED light source unit and the laser light source unit;

the first signal controller is used for carrying out signal modulation and control on the LED light source unit and/or the laser light source unit.

Optionally, the method further includes: a collimation module;

the collimation module comprises a plurality of collimation elements, and the collimation elements are used for collimating light emitted by the first LED, the second LED, the third LED or the laser.

Optionally, the beam combining module includes: a first beam combining element and a second beam combining element; wherein the content of the first and second substances,

the first beam combining element is arranged on a common optical path of the first LED, the second LED and the third LED, and is used for combining the red light, the green light and the blue light to obtain three primary color mixed light and transmitting the three primary color mixed light along a first direction;

the second beam combining element is arranged in the first direction of the first beam combining element, and is used for combining the three primary color mixed light and the yellow laser light to obtain the mixed color light and transmitting the mixed color light along the first direction.

Optionally, the beam combining module further includes: a reflective element;

the reflecting element is arranged in a first direction of the second beam combining element, and is used for reflecting the mixed color light to a second direction, the first direction and the second direction are in the same plane, and the first direction is intersected with the second direction.

Optionally, the color mixing light source module further includes: a heat sink;

the heat sink is used for transmitting heat generated by the LED light source unit and the laser light source unit outwards.

Optionally, the method further includes: an imaging module;

the imaging module is used for obtaining a projection image based on the projection light.

Optionally, the dodging module includes: a dodging element and a relay lens; wherein the content of the first and second substances,

the dodging element is used for dodging and shaping the mixed color light to obtain the mixed color light in a rectangular light spot shape;

the relay lens is used for imaging the mixed color light rays with the rectangular facula shape on the imaging module.

Optionally, the imaging module includes: a spatial light modulator and a second signal controller; wherein the content of the first and second substances,

the second signal controller is configured to transmit a modulation signal to the spatial light modulator to cause the spatial light modulator to output the projection image based on the modulation signal.

According to the technical scheme, the projection system comprises the color mixing light source module, the beam combining module and the light uniformizing module, wherein the color mixing light source module is used for providing three primary colors LED light and yellow laser light, the three primary colors LED light and the yellow laser light are combined through the beam combining module to form color mixing light, the color mixing light is subjected to light uniformizing and shaping treatment through the light uniformizing module to obtain projection light for projection, the yellow laser light is utilized in the system to solve the problem that the three primary colors LED light cannot fully traverse a yellow part, the problem of poor color rendering capability of the projection system is solved, and meanwhile, only one laser light is adopted in the system, so that the problem of large heat dissipation caused by the fact that the laser light source is adopted as working light is solved.

Drawings

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

Fig. 1 is a schematic structural diagram of a projection system according to an embodiment of the present application;

FIG. 2 is a schematic diagram of a projection system according to another embodiment of the present application;

FIG. 3 is a schematic diagram of a projection system according to another embodiment of the present application;

FIG. 4 is a schematic diagram of spectra of a first LED, a second LED, and a third LED provided by an embodiment of the present application;

FIG. 5 is a schematic spectrum diagram of a mixed-color light source module according to an embodiment of the present application;

FIG. 6 is another aspect of the present application;

FIG. 7 is a schematic diagram of a reflection spectrum of a second beam combining element according to an embodiment of the present application;

FIG. 8 is a spectral diagram of mixed-color light from the projection system of FIG. 2 including the second beam combining element of FIG. 7 according to one embodiment of the present application;

FIG. 9 is a schematic diagram of a reflection spectrum of a second beam combining element according to another embodiment of the present application;

FIG. 10 is a spectral diagram of mixed-color light of the projection system shown in FIG. 3 including the second beam combining element shown in FIG. 9 according to an embodiment of the present application.

Detailed Description

As described in the background art, the related art projection system using an LED or a laser as a light source has a problem of poor display capability or large heat dissipation.

The inventor researches and finds that the LED has the advantages of high light efficiency, small volume, low cost and the like compared with the traditional light sources such as a high-pressure mercury lamp and a halogen lamp. Monochromatic LED light sources are narrow in spectral width (tens of nanometers in magnitude), have higher color saturation and larger color gamut, display natural colors more truly and vividly, and the color rendering capability of the monochromatic LED light sources is far less than the color resolution limit of human eyes. In addition, the luminous energy density (luminous flux emitted per unit area) of the LED has reached a bottleneck, and the luminous area of the LED must be increased in order to improve the luminance of the LED, thereby increasing the difficulty of designing the light path, increasing the volume of the projection system, and resulting in higher cost. The basic direction of application of LED projectors is therefore in home theatres, small conference rooms etc. In addition, for the conventional LED projection system with three primary colors of red, green and blue, the conversion efficiency is limited, and the breakthrough on the brightness of the projected image cannot be realized, and the problem that the yellow part cannot be traversed sufficiently exists, so that the household projector cannot meet the DCI digital cinema standard.

The laser light source has the advantages of high brightness, high monochromaticity and the like, the monochromatic spectral width of the laser light source is narrower (nanometer magnitude) compared with that of an LED light source, the saturation is higher, the color development capability of a projection system taking pure laser as the light source is close to the color resolution limit of human eyes, and the laser projection system is a projection technology with great prospect. The current relatively mature laser projection scheme usually adopts a two-color wheel mode of a fluorescent wheel and a filter wheel, namely, a blue semiconductor laser irradiates fluorescent powder to excite yellow-green light, the yellow-green light is then filtered by the filter wheel to generate red light and green light with higher saturation, the red light and the green light and transmitted blue laser form three primary colors, and a required image is generated through the ratio of the three primary colors. The method needs to use high-power and long-time laser to irradiate the fluorescent wheel, so that the fluorescent wheel generates high temperature locally, the fluorescent efficiency is reduced, and the size of the optical engine is increased by using the color wheel. The timing signals of the double color wheel and the three primary color LED are difficult to synchronize, which is inconvenient for adding extra light sources to optimize the system. Another solution is a three-primary-color pure laser projection method, which performs effect optimization with pure laser. Yet another approach is a projection system that uses red, green, and blue lasers as light sources. The laser has the color rendering capability close to the color resolution limit of human eyes, the color coordinate point of the laser is closer to the limit MacAdam boundary of the color resolution of the human eyes, the color gamut triangle is larger, and the high-brightness projection effect can be realized due to the characteristics of high directivity and high brightness of the laser. However, the heat dissipation amount of the laser is large, and the volume of the heat dissipation system is difficult to reduce, so that the volume cannot be effectively reduced.

The inventor finds that, for the existing red and blue LED projection light source technology, the spectral width is in the order of twenty nanometers, which is close to the color resolution capability of human eyes, whereas for the existing green LED projection light source technology, the spectral width is in the order of one hundred nanometers, which is low in saturation, which limits the color gamut size in the green direction of the projection system. Therefore, for a projection system of red, green and blue LED light sources, a yellow laser light source is added to complement the brightness and saturation of the green LED light source, and the color gamut of the yellow region is expanded, so as to obtain a high-brightness large-color-gamut projection effect.

Based on the above research, the embodiment of the present application provides a projection system, which includes a color mixing light source module, a beam combining module and a light uniformizing module, wherein the color mixing light source module is configured to provide three primary color LED light and yellow laser light, the three primary color LED light and the yellow laser light form color mixing light after being combined by the beam combining module, the color mixing light is subjected to light uniformizing and shaping by the light uniformizing module to obtain projection light for projection, the yellow laser light is utilized in the system to solve the problem that the three primary color LED light cannot be fully traversed at a yellow part, the problem of poor color rendering capability of the projection system is solved, and meanwhile, only one laser light is utilized in the system, so that the problem of large heat dissipation caused by totally adopting a laser light source as a working light is avoided.

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

An embodiment of the present application provides a projection system, as shown in fig. 1, including: the light source module 100, the beam combining module 200 and the dodging module 300 are mixed; wherein the content of the first and second substances,

the color mixing light source module 100 is configured to provide three primary color LED light and yellow laser light;

the beam combining module 200 is configured to combine the three primary color LED light beams into a first combined light beam, and combine the first combined light beam and the yellow laser light beam into a mixed color light beam;

the dodging module 300 is configured to dodge and shape the color-mixed light to obtain projection light.

Alternatively, the three primary color LED light refers to three primary color light emitted by the LED light emitting element, and the three primary color light may include red light, green light, and blue light.

The yellow laser light refers to yellow light emitted by a laser.

The projection system provided by the embodiment utilizes the yellow laser light to make up the problem that the three primary colors of LED light cannot fully traverse the yellow part, thereby solving the problem of poor color rendering capability of the projection system.

The projection system fully utilizes the advantages of small size, low cost, high laser brightness, high saturation and large display color gamut of the LED, and obtains the projection system with higher brightness and larger color gamut under the conditions of low cost and small size.

In addition, the projection system omits a color wheel which is necessary in a laser fluorescence projection system, further reduces the volume, makes the system static, and eliminates the influence caused by the high-speed rotation of the color wheel.

A description is given below of a possible structure of each module of the projection system provided in the embodiments of the present application.

Optionally, as shown in fig. 2 and 3, the color mixing light source module 100 includes: an LED light source unit and a laser light source unit; wherein the content of the first and second substances,

the LED light source unit includes a plurality of LEDs 10, and at least a first LED, a second LED and a third LED are included in the plurality of LEDs 10, wherein the first LED is used for emitting red light, the second LED is used for emitting green light, and the third LED is used for emitting blue light;

the laser light source unit comprises at least one laser 11, and the laser 11 is used for emitting yellow laser light.

Referring to fig. 4, fig. 4 shows a spectral diagram of a first LED, a second LED and a third LED, the intensity of the individual primary colors being determined by the white balance of the projection system. Of course, in other embodiments of the present application, the spectral curves of the first LED, the second LED and the third LED may also be determined according to actual requirements.

In fig. 2, the color mixing light source module 100 includes one laser 11, and in fig. 3, the color mixing light source module 100 includes two lasers 11. In other embodiments of the present application, the number of the lasers 11 in the color mixing light source module 100 may also be three, four, or five, and the like, which is not limited in the present application, depending on the actual situation. When the number of the lasers 11 in the mixed-color light source module 100 is more than 2, the spectrums of the laser light emitted by the lasers 11 may be the same or different, which is not limited in the present application.

Referring to fig. 5 and 6, fig. 5 shows a spectral diagram of the mixed color light source module 100 including one laser 11, and fig. 6 shows a spectral diagram of the mixed color light source module 100 including two lasers 11. The intensity of each primary color is determined by the white balance of the projection system. Of course, in other embodiments of the present application, the spectral profile of the laser 11 may also be determined according to actual requirements.

Accordingly, still referring to fig. 2 or 3, the beam combining module 200 includes: a first beam combining element 21 and a second beam combining element 22; wherein the content of the first and second substances,

the first beam combining element 21 is disposed on a common optical path of the first LED, the second LED and the third LED, and the first beam combining element 21 is configured to combine the red light, the green light and the blue light to obtain three primary color mixed light and transmit the three primary color mixed light along a first direction;

the second beam combining element 22 is disposed in a first direction of the first beam combining element 21, and the second beam combining element 21 is configured to combine the three primary color mixed light and the yellow laser light to obtain the mixed color light and transmit the mixed color light along the first direction.

The number of the second beam combining elements 22 is equal to the number of the lasers, in fig. 2, the number of the second beam combining elements 22 is one, and in fig. 3, the number of the second beam combining elements 22 is two.

Alternatively, the first beam combining element 21 may be a dichroic mirror or an X-prism.

The second beam combining element 22 may be a narrow band pass or narrow band stop filter matched to the wavelength of the yellow laser beam, or may be an interference narrow band pass filter or a holographic optical element corresponding to the wavelength of the yellow laser beam.

Optionally, still referring to fig. 2 or 3, the projection system further comprises: an optical modulation module;

the light modulation module includes: a circuit board 12 and a first signal controller 13; wherein the content of the first and second substances,

the circuit board 12 is used for bearing the LED light source unit and the laser light source unit;

the first signal controller 13 is configured to perform signal modulation and control on the LED light source unit and/or the laser light source unit.

The first signal controller 13 is electrically connected to the LED light source unit and/or the laser light source unit through a trace on the circuit board, so that the first signal controller 13 can perform signal transmission with the LED light source unit and/or the laser light source unit.

Optionally, the first signal controller 13 may only perform signal modulation and control on the LED light source unit, may also only perform signal modulation and control on the laser light source unit, and may also perform signal modulation and control on both the LED light source unit and the laser light source unit, which is not limited in this application and is specifically determined according to actual situations.

Optionally, a collimating module is further shown in fig. 2 and fig. 3, where the collimating module includes a plurality of collimating elements, and the collimating elements are configured to collimate light emitted by the first LED, the second LED, the third LED, or the laser.

In fig. 2 and 3, the collimating element 41 for collimating the light emitted from the first LED, the second LED, or the third LED may be a lens or a lens group, and the collimating element 42 for collimating the light emitted from the laser may be an aspheric lens or a fiber coupling element.

In fig. 2 and 3, the beam combining module 200 further includes: a reflective element 23;

the reflecting element 23 is disposed in a first direction of the second beam combining element 22, the reflecting element 23 is configured to reflect the mixed color light to a second direction, the first direction and the second direction are in the same plane, and the first direction intersects with the second direction.

The reflecting element 23 may be a mirror, and the reflecting element 23 is configured to compress/fold the light path of the combined mixed-color light, so as to reduce the overall size of the projection system.

In addition, the existence of the reflecting element 23 can improve the robustness of the optical path, that is, under the condition that some errors occur in the process of building the optical path of the system, the light beam of the mixed-color light can still be shaped by the reflecting element 23, so that the mixed-color light meeting the requirements can be obtained.

Optionally, in an embodiment of the present application, the color mixing light source module 100 further includes: a heat sink;

More specifically, the heat sink transfers heat generated by the LED light source unit and the laser light source unit to the respective bases, so that the operating temperatures of the LED light source unit and the laser light source unit are maintained within a certain operating range.

The heat sink refers to a structure whose temperature does not change with the amount of heat energy transferred to the heat sink, and optionally, the heat sink may be a structure with better thermal conductivity, such as a copper pillar.

Optionally, still referring to fig. 2 or 3, the projection system further comprises: an imaging module;

Optionally, the imaging module includes: a spatial light modulator 51 and a second signal controller 52; wherein the content of the first and second substances,

the second signal controller 52 is configured to transmit a modulation signal to the spatial light modulator 51, so that the spatial light modulator 51 outputs the projection image based on the modulation signal.

Optionally, the dodging module 300 includes: the light uniformizing element 31 and the relay lens 32; wherein the content of the first and second substances,

the dodging element 31 is configured to perform dodging and shaping processing on the mixed color light to obtain a mixed color light in a rectangular light spot shape;

the relay lens 32 is configured to image the rectangular spot-shaped mixed-color light on the imaging module.

In the structure shown in fig. 2, when the second beam combiner 22 is an interference narrow band pass filter, referring to fig. 7, fig. 7 shows a schematic reflection spectrum of the second beam combiner 22. The yellow laser light and the three primary colors of LED light are combined coaxially by the second beam combining element 22, and the combined spectrum is shown in fig. 8, and the brightness and saturation of the wavelength portion of the yellow laser line are greatly improved.

In the structure shown in fig. 3, when the second beam combining element 22 is an interference narrow band pass filter, referring to fig. 9, fig. 9 shows a schematic reflection spectrum diagram of the second beam combining element 22, and the upper and lower diagrams in fig. 9 correspond to two bands of laser light sources respectively. The yellow laser light and the three primary colors of LED light are combined coaxially by the second beam combining element 22, and the combined spectrum is shown in fig. 10, and the brightness and saturation of the wavelength portion of the yellow laser line are greatly improved.

In fig. 3-10, the abscissa is wavelength in nanometers (nm), the ordinate of fig. 5, 6, 7, and 9 is reflectance, and the ordinate of fig. 4, 8, and 10 is normalized intensity.

To sum up, the embodiment of the present application provides a projection system, this projection system includes mixed color light source module 100, closes and restraints module 200 and dodges the light module 300, wherein, mixed color light source module 100 is used for providing three primary colors LED light and yellow laser light, three primary colors LED light and yellow laser light form mixed color light after closing a bundle module 200, mixed color light is even after light and the plastic processing through dodging module 300, obtain projection light and carry out the projection, utilize yellow laser light to compensate the problem that three primary colors LED light can't fully traverse at yellow part in this system, the poor problem of projection system color rendering capability has been solved, only adopted a laser light in this system simultaneously, avoided all adopting laser light source as the work light and the big problem of heat dissipation that leads to.

Features described in the embodiments in the present specification may be replaced with or combined with each other, each embodiment is described with a focus on differences from other embodiments, and the same and similar portions among the embodiments may be referred to each other.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A projection system, comprising: the device comprises a color mixing light source module, a beam combining module and a light homogenizing module; wherein the content of the first and second substances,

2. The projection system of claim 1, wherein the color mixing light source module comprises: an LED light source unit and a laser light source unit; wherein the content of the first and second substances,

3. The projection system of claim 2, further comprising: an optical modulation module;

4. The projection system of claim 2, further comprising: a collimation module;

5. The projection system of claim 2, wherein the beam combining module comprises: a first beam combining element and a second beam combining element; wherein the content of the first and second substances,

6. The projection system of claim 5, wherein the beam combining module further comprises: a reflective element;

7. The projection system of claim 2, wherein the color mixing light source module further comprises: a heat sink;

8. The projection system of claim 1, further comprising: an imaging module;

9. The projection system of claim 8, wherein the dodging module comprises: a dodging element and a relay lens; wherein the content of the first and second substances,

10. The projection system of claim 8, wherein the imaging module comprises: a spatial light modulator and a second signal controller; wherein the content of the first and second substances,