CN114545717B - projection device - Google Patents

Abstract

The present invention relates to a projection apparatus. The projection device includes: a laser light source; the phase space light modulator is used for receiving the laser emitted by the laser light source, modulating the laser according to the image to be projected to obtain first modulated illumination light, wherein the first modulated illumination light comprises light spots and dark areas among the light spots; and the optical assembly is used for receiving the first modulated illumination light, and widening the light spots of the first modulated illumination light so as to expand the light spots to the dark area, thereby obtaining second modulated illumination light, and the overlapping area between the light spots of the second modulated illumination light is not more than a preset threshold value. The invention can improve the uniformity of illumination light and is beneficial to improving the visual experience of audiences.

Description

projection device

This application is a divisional application with the application number 201811550823.6 submitted by the applicant on December 18, 2018, and the title of the invention is "projection device".

technical field

The present invention relates to the technical field of projection display, in particular to a projection device.

Background technique

In the laser phosphor projection system, the light spot will be widened in the process of using the dynamically modulated array illumination source to realize HDR display. After each small light spot is widened, there will be overlapping areas, which will lead to the deterioration of the uniformity of the illumination light incident on the spatial light modulator and affect the brightness uniformity of the projected image.

However, those skilled in the art have not been aware of the existence of this problem, therefore, it is urgent to provide an effective solution to this technical problem.

Contents of the invention

In order to solve the technical problem of poor brightness uniformity of projected images in existing projection systems, the present invention provides a projection device, wherein the projection device includes:

laser light source;

a phase spatial light modulator, configured to receive the laser light emitted by the laser light source, and modulate the laser light according to the image to be projected to obtain a first modulated illumination light, the first modulated illumination light includes a light spot and a dark area between the light spots; and

An optical component, configured to receive the first modulated illumination light, widen the light spot of the first modulated illumination light so that the light spot expands to the dark area, so as to obtain the second modulated illumination light, and the absolute value of the overlapping area between the light spots of the second modulated illumination light is not greater than a preset threshold.

Compared with the prior art, the phase spatial light modulator of the projection device provided by the present invention can obtain the first modulated illumination light by modulating the laser light according to the image to be projected after receiving the laser light emitted by the laser light source, and the modulated first modulated illumination light includes light spots and dark areas between the light spots. Thereafter, the optical component is used to widen the received light spot of the first modulated illumination light so that the light spot expands to the dark area to obtain the second modulated illumination light, and after each light spot covers the dark area between the light spots, the overlapping area between each light spot is not greater than a preset threshold value, thereby facilitating the projection device to provide illumination light with a more uniform light distribution.

Further, since the light distribution of the second modulated illumination light is uniform, when it is irradiated to the amplitude spatial light modulator of the projection device, the transition between the dark part and the bright part of the image light to be projected obtained after the amplitude spatial light modulation is relatively smooth, which can achieve a better local darkening effect, and is conducive to improving the viewing comfort of the human eye and helping to improve the visual experience of the audience.

By using the phase spatial light modulator to modulate the illumination light, the first modulated illumination light with corresponding brightness distribution can be modulated in real time according to the image to be projected, so as to realize the projection of a high dynamic range image, and can relatively guarantee the brightness of the projected image, which is conducive to improving the performance of the projection device.

Furthermore, on the basis of the optical components including the fluorescent pink wheel and the corresponding lens, the dark area reserved by the interference pattern can effectively reduce the influence of the light spot on the uniformity of the brightness distribution during the widening process, which is conducive to achieving a better high dynamic range image projection effect.

Description of drawings

FIG. 1 is a schematic structural diagram of a projection device according to a preferred embodiment of the present invention.

Fig. 2 is a schematic diagram of the structure of an unmodulated interference pattern in an embodiment.

Fig. 3 is a schematic diagram of the structure of a modulated interference pattern in an implementation manner.

Fig. 4 is a schematic diagram of the effect of using the fluorescent pink wheel to widen the first modulated illumination light generated by modulation in Fig. 3 .

Fig. 5 is a schematic diagram of the simulation effect of the shock response function corresponding to widening the light spot at the central position through the collecting lens and the relay lens.

FIG. 6 is a schematic diagram of the simulation effect of the shock response function corresponding to widening the light spot at the edge position through the light collecting lens and the relay lens.

FIG. 7 is a schematic diagram of the comparison of the light distribution effect after the illumination light shown in FIG. 4 is emitted and the light distribution effect after the illumination light is further widened by the light collecting lens and the relay lens after the illumination light is emitted.

Fig. 8 is a test image.

FIG. 9 is a luminance signal diagram obtained corresponding to FIG. 8 and divided into 15×10 regions.

FIG. 10 is a schematic diagram of a rectangular illumination area of the first modulated illumination light obtained through modulation according to the luminance signal in FIG. 9 .

FIG. 11 is a schematic diagram of the rectangular illumination area of the first-level modulated illumination light obtained after the first modulated illumination light in FIG. 10 is widened by the fluorescent pink wheel.

FIG. 12 is a schematic diagram of a rectangular illumination area of the secondary second modulated illumination light obtained after the primary second modulated illumination light in FIG. 11 is widened by the optical system.

FIG. 13 is a flowchart of a method for controlling a projection device according to an embodiment of the present invention.

Fig. 14 is a schematic structural diagram of a projection system in a time-sequential light combination mode in an embodiment.

Fig. 15 is a schematic diagram of the structure of a projection system using time-sequential light combination and spatial light combination in an embodiment.

Fig. 16 is a schematic structural diagram of a projection system using spatial photosynthesis in an embodiment.

Explanation of main component symbols

projection device 100

Laser light source 11

Phase Spatial Light Modulator 12

Optical Components 13

Projection System 200, 300, 500

Image to be projected 21, 31, 51

Image processor 22, 32, 52

Laser 23, 33, 53

Phase spatial light modulator 24, 34, 54

Neon Pink Wheel 25, 35, 55

Filters 26

lens 27

Amplitude Spatial Light Modulator 28

Projection lens 29, 42, 64

Projection screen 30, 43, 65

Optical splitter 36, 56

First lens 37, 57

Second lens 39, 59

third lens 61

The first amplitude modulation unit 38, 58

Second amplitude modulation unit 40, 60

The third amplitude modulation unit 62

Light combiner 41, 63

The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings.

Detailed ways

Please refer to FIG. 1 . FIG. 1 is a schematic structural diagram of a projection device according to a preferred embodiment of the present invention. The projection device of the present invention can be applied to projection equipment such as movie machines, engineering machines, commercial teaching machines, splicing walls, laser TVs, and micro-projectors.

As shown in FIG. 1 , the projection device 100 may include a laser light source 11 , a phase spatial light modulator 12 , and an optical component 13 . The phase spatial light modulator 12 is used to receive the laser light emitted by the laser light source 11, and modulate the laser light according to the image to be projected to obtain the first modulated illumination light. The second modulated illumination light is formed when the first modulated illumination light is transmitted through the optical component 13, and the optical component 13 widens the light spots of the incident first modulated illumination light so that each light spot expands to a dark area between the light spots, and the absolute value of the overlapping area between the widened light spots is not greater than a preset threshold.

Further, in order to ensure that the light field used for projection display does not have a fault phenomenon, that is, there will be no phenomenon of no light in a certain light field, the overlapping area between the widened light spots can be set as a positive number. Preferably, the overlapping area between the light spots after being widened by the optical component 13 is set to zero. At this time, because there is no dark area in the projection light field, normal projection display is guaranteed, and because the light field intensity at the junction between each light spot is consistent with the light field intensity inside the light spot, the uniformity of the projection display light field is realized to the greatest extent.

It should be noted that in practical applications, there are complex functions and interactions between the components of the projection display system, which is not an ideal optical system. Under the inspiration of this technical solution, those skilled in the art set the overlapping area between the light spots after stretching to a value that is roughly zero. range. In an embodiment where the distance between the light spots after stretching is set to a small value, the overlapping area between the light spots after stretching can be regarded as a negative value whose absolute value is equal to the distance between the light spots after stretching.

It should be noted that the preset threshold in this technical solution can be set through multiple experiments.

In addition, the overlapping area of the light spots in the second modulated illumination light is not only related to the extent to which the optical components 13 widen the light spots in the first modulated illumination light, but also related to the size of the light spots of the first modulated illumination light itself and the distance between the light spots.

In one embodiment, the modulated light field of the light source is shown in FIG. 2 . The first modulated illumination light is divided into a plurality of adjacent and continuous illumination areas b according to the image brightness distribution. The spot b1 of the first modulated illumination light is smaller than the illumination area b, and a dark area a1 is also set in the illumination area b. The relationship between the size of the light spot b1 of the first modulated illumination light and the size of the illumination area b is determined according to the size of the illumination area on the wavelength conversion element, the spread of the light spot on the wavelength conversion element and the number of light spots in the first modulated illumination light. The spread of the light spot of the first modulated illumination light on the wavelength conversion element is determined by the thickness of the material of the conversion layer, the size distribution and concentration of the scattering particles. For example, under a fluorescent glass layer with a thickness of about 180um, the widening radius of the light spot is about 0.1mm.

In this embodiment, the laser light source 11 can be a monochromatic laser, such as a blue laser, or other lasers. Preferably, the laser light source 11 can also be an array illumination light source, and the phase spatial light modulator can be a liquid crystal-based spatial light modulator such as an LCOS spatial light modulator or an LCD spatial light modulator.

In this embodiment, the phase spatial light modulator 12 is used to perform phase modulation on the received light according to the image to be projected to obtain the first modulated illumination light. The first modulated illumination light is an illumination area having a brightness distribution corresponding to the brightness distribution area in the image to be projected, and the illumination area may be a rectangular illumination area corresponding to the shape of the image to be projected (for example, the shape of the image is mostly a 16:9 or 4:3 rectangle).

It should be understood that, in the case that the image to be projected is a dynamic image, the phase spatial light modulator 12 may modulate each frame of image in real time to obtain the first modulated illumination light having a corresponding brightness distribution illumination light field. However, when there is a difference between the image frames, the brightness distribution in the modulated rectangular illumination light field is relatively different. The brightness of the first modulated illumination light and the brightness information of the image to be projected may satisfy a preset relationship, and the preset relationship includes any of the following:

The brightness of the first modulated illumination light is equal to the maximum brightness of the pixel of the image to be projected;

The brightness of the first modulated illumination light is equal to the maximum brightness of pixels in the preset area of the image to be projected; and

The brightness of the first modulated illumination light is equal to the average brightness of each pixel in the image to be projected.

In this embodiment, the optical component may include an optical device such as a lens. Therefore, after receiving the first modulated illumination light, based on the optical characteristics of the optical component, the light spot in the first modulated illumination light may be widened. Possible situations after widening include:

1) The light spots do not overlap and cannot completely cover the dark area;

2), each light spot does not overlap, and completely covers the dark area;

3) Each spot overlaps, and the overlapping area is small;

4) Each light spot overlaps, and the overlapping area is relatively large.

According to the above situation, it can be seen that both cases 1) and 4) will bring about the problem of relatively uneven distribution of illumination light, while case 3) is less likely to cause uneven illumination distribution, while case 2) is a relatively ideal situation, that is, the widened light spot just covers the dark area, and the distribution of illumination light in each area is uniform. Therefore, choosing the situations 2) and 3) here can relatively meet the requirement of uniform distribution of the illumination light field.

It can be understood that since the size of the reserved dark area is relatively determined, the optical component 13 can be equipped with one or more lenses of the same type or different types to perform light processing to achieve stretching adjustment, so that the overlapping area of each spot after widening is not greater than the preset threshold. It should be understood that, corresponding to case 2), the overlapping area of each light spot after the widening is equal to zero. Corresponding to case 3), the overlapping area of each light spot after the widening is relatively small, and the preset threshold may be the maximum area of non-uniform illumination light distribution allowed by the user. Therefore, in the process of using the optical component 13 to perform light processing to obtain the second modulated illumination light, multi-level modulation may be included, so as to realize the adjustment of the overlapping area of each light spot after widening.

In this embodiment, after receiving the laser light emitted by the laser light source, the phase spatial light modulator 12 modulates the laser light according to the image to be projected to obtain the first modulated illumination light, and the modulated first modulated illumination light includes light spots and dark areas between the light spots. Thereafter, optical components are used to perform optical processing on the received first modulated illumination light to obtain second modulated illumination light, and the obtained second modulated illumination light is to widen the light spots of the first modulated illumination light, so that each light spot covers the dark area between the light spots, and satisfies the condition that the overlapping area of each light spot after widening is not greater than a preset threshold value, thereby facilitating the provision of illumination light with relatively uniform light distribution. At the same time, since the brightness of the second modulated illuminating light is relatively uniform, when it is irradiated to the amplitude spatial light modulator of the projection device, the transition between the dark part and the bright part of the image light to be projected obtained after the amplitude spatial light modulation is relatively smooth, which can achieve a better local darkening effect, and is conducive to improving the viewing comfort of the human eye and helping to improve the visual experience of the audience.

In this implementation manner, preferably, the overlapping area between the widened light spots is equal to zero, so as to obtain the best uniformity of the light distribution. It should be understood that in the actual application of optical devices, due to the broadening characteristics and other factors, there is a possibility that the widened light spots may be partially deformed, making it difficult for the light spots to completely cover the reserved dark area without overlapping. Therefore, the overlapping area of each light spot equal to zero here can be regarded as the overlapping area of each light spot approaches zero.

In this embodiment, since the laser light emitted by the laser light source is coherent light, the first modulated illumination light modulated by the phase spatial light modulator 12 is still coherent light. In order to alleviate the speckle problem that may be caused by the coherence of laser light, in a specific embodiment of this embodiment, the optical component 13 may include a wavelength conversion element to perform wavelength conversion on a part of the first modulated illumination light to obtain incoherent light. relationship. Since the phase spatial light modulator 12, especially a liquid crystal phase spatial light modulator, the phase delay of the outgoing light is inversely proportional to the wavelength, the light of different colors/wavelengths emitted by the phase spatial light modulator 12 appears to be separated and scattered, that is, there is a very serious dispersion problem, which affects the color uniformity of the picture. In addition, the incoherent light obtained after conversion by the wavelength conversion element is mostly compound light (light of the same color mixed), which will be dispersed through an optical lens or the like. After the first modulated illumination light passes through the wavelength conversion element, the proportion of coherent light is reduced, which is beneficial to alleviate the problem of dispersion of light emitted by the projection device.

In this embodiment, the optical component may further include a light collecting lens and a relay lens, the light collecting lens is used to collect the incoherent light and the coherent light (that is, the other part of the first modulated illumination light not converted by the wavelength conversion element), and the relay lens is used to relay and transmit the light collected by the light collecting lens, thereby achieving a certain degree of broadening and simultaneously realizing the support for light collection and transmission.

It can be understood that the wavelength converting element may be a fluorescent pink wheel or a fixed fluorescent sheet. When the wavelength conversion element is a fluorescent pink wheel, the wavelength conversion of a part of the first modulated illumination light is performed by using the phosphor layer of the fluorescent pink wheel. Conversely, the thickness of the phosphor layer can determine the image broadening of the wavelength conversion element. For example, when the thickness of the phosphor layer is 180 microns, the imaging broadening for a spot power of 3 decibels is about 0.1 mm, that is, the spot is 0.1 mm larger than the periphery of the spot incident on the phosphor layer, and the shock response of the fluorescent pink wheel can be approximated as a Gaussian distribution function with a spot power of 3 decibels and an imaging broadening of 0.1 mm. Therefore, a corresponding functional relationship can be established based on the above three values to support the adjustment of the overlapping area of each spot that is widened.

In this embodiment, when the wavelength conversion element is a fluorescent pink wheel, the size of the overlapping area of each widened light spot is determined by one or more of the thickness of the fluorescent layer of the fluorescent pink wheel, the scattering particles, the concentration of scattering particles, and the lens aberrations of the collecting lens and the relay lens.

In an extended implementation of this embodiment, the projection device may further include an amplitude spatial light modulator for receiving the modulated illumination light, and the amplitude spatial light modulator is configured to modulate the second modulated illumination light according to the image to be projected to obtain image light to be projected.

It can be understood that, the image light to be projected can be emitted through the projection lens to obtain a projected image reproducing the image to be projected.

Referring to FIG. 2 , FIG. 2 is a schematic structural diagram of an unmodulated interference pattern in an implementation manner. As shown in FIG. 2 , the interference pattern is rectangular, including reserved dark areas a1 and light spots b1 , each light spot b1 is rectangular, and the dark areas a1 are regularly spaced from each light spot b1 .

It can be understood that, according to different projection requirements, the interference pattern can also be set as a pattern of other shapes, such as a circular pattern, a regular hexagonal pattern, and the like.

Referring to FIG. 3 , FIG. 3 is a schematic structural diagram of a modulated interference pattern in an implementation manner. As shown in Figure 3, the interference pattern is also rectangular, including the reserved dark area a2 and light spot b2, and also includes an area c corresponding to the brightness distribution area in the image to be projected, the position and light intensity of the area c are determined by the position and light intensity of the brightness distribution area in the image to be projected.

Referring to FIG. 4 , FIG. 4 is a schematic diagram showing the effect of broadening the modulated and generated first modulated illumination light in FIG. 3 by using a fluorescent pink wheel. As shown in FIG. 4 , compared with FIG. 3 , the phosphor layer of the fluorescent pink wheel widens each light spot in the received first modulated illumination light to obtain the widened light spot distribution effect, so that the brightness of the area corresponding to the dark area a2 in FIG. 3 is improved, the grid pattern presented is relatively blurred, and the light field brightness distribution is relatively uniform. It can be understood that after the light spot is widened, the edge of the area corresponding to the area c becomes blurred.

5 and 6, wherein, FIG. 5 is a schematic diagram of the simulation effect of the shock response function corresponding to widening the light spot at the central position through the light collecting lens and the relay lens; FIG. 6 is a schematic diagram of the simulation effect of the shock response function corresponding to widening the light spot at the edge position through the light collecting lens and the relay lens. Comparing the effects shown in Figure 4 and Figure 5, there is a large difference in the image formed by the light spot located at the edge and the light spot located at the center, and this difference is determined by the lens aberration. Therefore, when the light broadened by the phosphor layer passes through the collecting lens and the relay lens, the passing light will be further broadened due to the lens aberration. It can be understood that, since neither the light-collecting lens nor the relay lens involves light conversion, they can be collectively referred to as an optical system.

Referring to FIG. 7, FIG. 7 is a schematic diagram of the comparison of the light distribution effect after the illumination light is emitted and the light distribution effect after the illumination light is emitted and further widened by the collecting lens and the relay lens shown in FIG. 4 . It can be seen from the figure that the illumination light (the illumination light after the first modulated illumination light is broadened by the phosphor layer of the fluorescent pink wheel) exits, and then the light distribution is further uniformed by the light collecting lens and the relay lens, and the brightness curve becomes relatively smooth.

Referring to Fig. 8, Fig. 8 is a test image; Fig. 9 is a luminance signal diagram corresponding to Fig. 8 divided into 15×10 regions; Fig. 10 is a schematic diagram of a rectangular lighting area of the first modulated illumination light obtained by modulating the luminance signal in Fig. 9; Fig. 11 is a schematic diagram of a rectangular illuminated area of a first-level second modulated illumination light obtained after the first modulated illumination light in Fig. 10 is widened by a fluorescent pink wheel; Schematic diagram of the rectangular illumination area of a light.

In this embodiment, the image in FIG. 8 is divided into 15×10 brightness distribution areas. After the brightness is collected, the obtained brightness distribution signal is shown in FIG. 9 , and each brightness distribution position corresponds to each other. After the rectangular illumination area of the first modulated illumination light obtained by modulating according to the brightness signal in FIG. 9 , an effect diagram of the rectangular illumination area of the first modulated illumination light as shown in FIG. 10 is obtained.

As shown in Figure 11, it is an effect diagram of the rectangular lighting area of the first-level second modulated lighting light obtained after the first modulated lighting light is widened by the fluorescent pink wheel. After the widening, the grid pattern presented is relatively blurred, and the brightness distribution of the light field is relatively uniform.

As shown in FIG. 12 , it is an effect diagram of the rectangular illumination area of the secondary second modulated illumination light obtained after the first-level second modulated illumination light is broadened by the optical system, and the light distribution is relatively more uniform.

Corresponding to the projection device provided above, the present invention also provides a method for controlling the projection device. It can be understood that since the above projection device has a description of the function, use and/or effect of the corresponding optical device, it will not be repeated here.

As shown in FIG. 13 , it is a flowchart of a method for controlling a projection device according to an embodiment of the present invention, and the method may include the following steps:

S101: Control the laser light source to output laser.

S102: Modulate the received laser light according to the image to be projected to obtain first modulated illumination light, where the first modulated illumination light includes light spots and dark areas between the light spots.

S103: Using an optical component to widen the light spots of the first modulated illumination light so as to cover the dark areas between the light spots, so as to obtain the second modulated illumination light, the overlapping area between the light spots of the second modulated illumination light is not greater than a preset threshold.

In this embodiment, after receiving the laser light emitted by the laser light source, the phase spatial light modulator modulates the laser light according to the image to be projected to obtain the first modulated illumination light, and the modulated first modulated illumination light includes light spots and dark areas between the light spots. Thereafter, optical components are used to perform optical processing on the received first modulated illumination light to obtain second modulated illumination light, and the obtained second modulated illumination light satisfies the condition of widening the light spots of the first modulated illumination light, so that each light spot covers the dark area between the light spots, and the overlapping area of each light spot after widening is not greater than a preset threshold, which is conducive to the provision of illumination light with relatively uniform light distribution.

In this implementation manner, preferably, after control, the overlapping area between the widened light spots is equal to zero.

In this implementation manner, the phase spatial light modulator is a liquid crystal based spatial light modulator. Here, the optical component includes a wavelength conversion element for performing wavelength conversion on a part of the first modulated illumination light to obtain incoherent light.

Certainly, the optical assembly further includes a collecting lens and a relay lens, the collecting lens is used to collect the incoherent light and another part of the first modulated illumination light; the relay lens is used to relay and transmit the light collected by the collecting lens.

When the wavelength conversion element is a fluorescent pink wheel, the size of the overlapping area of each of the widened light spots is determined by one or more of the thickness of the fluorescent layer of the fluorescent pink wheel, the scattering particles, the concentration of scattering particles, and the lens aberrations of the collecting lens and the relay lens.

In this embodiment, the brightness of the first modulated illumination light and the brightness information of the image to be projected satisfy a preset relationship, and the preset relationship includes any of the following:

The brightness of the first modulated illumination light is equal to the maximum brightness of the pixel of the image to be projected;

The brightness of the first modulated illumination light is equal to the maximum brightness of pixels in the preset area of the image to be projected; and

The brightness of the first modulated illumination light is equal to the average brightness of each pixel in the image to be projected.

It can be understood that, after obtaining the second modulated illumination light, the amplitude spatial light modulator may also be used to modulate the second modulated illumination light according to the image to be projected to obtain the image light to be projected.

Referring to FIG. 14 , FIG. 14 is a schematic structural diagram of a projection system in a time-sequential light-combining mode in an embodiment. The projection system 200 of this embodiment first utilizes the image processor 22 to analyze the to-be-projected image 21 to obtain brightness information and RGB three primary color information of the to-be-projected image, wherein the phase spatial light modulator 24 is configured to modulate the laser light emitted by the laser 23 according to the brightness information of the to-be-projected image to obtain the first modulated illumination light. Thereafter, the first modulated illumination light is emitted onto the fluorescent pink wheel 25, and red light, green light, and blue light are generated by it in time sequence, and the generated red light, green light, and blue light are filtered by the filter 26 to output light of a specified color, and are transmitted to the amplitude spatial light modulator 28 under the optical action of the lens 27, and the light transmitted to the amplitude spatial light modulator 28 is obtained by expanding under the action of the fluorescent pink wheel 25, the filter 26, and the lens 27. The second modulated illumination light includes red second modulated illumination light, green second modulated illumination light and blue second modulated illumination light.

In this embodiment, the phosphor layer of the fluorescent pink wheel 25 and the lens 27 are used to widen the first modulated illuminating light, so that the light distribution of the second modulated illuminating light irradiated on the amplitude spatial light modulator 28 is relatively uniform. Therefore, the brightness of the image light to be projected and generated by the modulation of the amplitude spatial light modulator 28 has a higher brightness reduction degree, which helps to improve the visual experience.

The amplitude spatial light modulator 28 respectively modulates the red second modulated illumination light, the green second modulated illumination light and the blue second modulated illumination light according to the RGB three primary color information of the image to load the image content information of the image to be projected to obtain the image light to be projected, and the image light to be projected is projected through the projection lens 29 to sequentially present a red light image, a green light image and a blue light image on the projection screen 30. It can be understood that, by utilizing the persistence of vision effect of the human eye, the above sequentially presented light can synthesize a corresponding color image in the human brain.

Referring to FIG. 15 , FIG. 15 is a schematic structural diagram of a projection system 300 that adopts time-sequential light combination and spatial light combination methods in an embodiment.

The projection system 300 of this embodiment also uses the image processor 32 to first analyze the image to be projected 31 to obtain brightness information and RGB three primary color information of the image to be projected, wherein the phase spatial light modulator 34 is configured to modulate the laser light emitted by the laser 33 according to the brightness information of the image to be projected to obtain the first modulated illumination light.

Thereafter, the first modulated illumination light is emitted onto the fluorescent pink wheel 35 to generate red light, green light and blue light. The generated red light, green light and blue light are divided into red and blue sequential light paths and green light paths or divided into red light light paths and green and blue sequential light paths under the action of the beam splitter 36.

In a specific embodiment: in the red and blue optical path, the red and blue sequential light is transmitted to the first amplitude modulation unit 38 under the optical action of the first lens 37, and is modulated by the first amplitude modulation unit 38 according to the image to be projected, so as to obtain the red second modulated illumination light to be projected image light and the blue image light to be projected. In the green light path, the green light is transmitted to the second amplitude modulation unit 40 under the optical action of the second lens 39 , and is modulated by the second amplitude modulation unit 40 according to the image to be projected to obtain green image light to be projected. Here, the first lens 37 and the second lens 39 can be collectively referred to as an optical system, and the first amplitude modulation unit 38 and the second amplitude modulation unit 40 can be collectively referred to as an amplitude spatial light modulator; the fluorescent pink wheel 35 can be a yellow fluorescent pink wheel, so the beam splitter 36 can be used to divide the white light generated by the yellow fluorescent pink wheel into red and blue sequential light transmitted on the red and blue light paths and green light transmitted on the green light path.

In another specific embodiment: in the red light path, the red light is transmitted to the first amplitude modulation unit 38 under the optical action of the first lens 37, and is modulated by the first amplitude modulation unit 38 according to the image to be projected to obtain red image light to be projected. In the green-blue light path, the green-blue sequential light is transmitted to the second amplitude modulation unit 40 under the optical action of the second lens 39, and the second amplitude modulation unit 40 performs modulation according to the image to be projected to obtain green image light to be projected and blue image light to be projected.

Thereafter, the red image light to be projected, the green image light to be projected, and the blue image light to be projected are received by the light combiner 41 , and the three primary colors of image light to be projected are guided to the same optical path for transmission.

Finally, the image lights of the three primary colors to be projected are projected through the projection lens 42 to display images on the projection screen 43 .

It can be understood that the fluorescent pink wheel 35 , the beam splitter 36 , the first lens 37 , and the second lens 39 in the projection system 300 can be regarded as the aforementioned optical components.

In this embodiment, the phosphor layer of the fluorescent pink wheel 35, the first lens 37, and the second lens 39 are used to widen the first modulated illumination light modulated by the phase spatial light modulator 34 to obtain the second modulated illumination light, and the brightness of the second modulated illumination light is relatively uniform, which is conducive to a higher brightness reduction degree of the image light to be projected and generated by the modulation of the amplitude spatial light modulation unit, and improves the visual experience.

Referring to FIG. 16 , FIG. 16 is a schematic structural diagram of a projection system 500 in a spatial photosynthesis mode in an embodiment. The projection system 500 of this embodiment first utilizes the image processor 52 to analyze the to-be-projected image 51 to obtain brightness information and RGB three primary color information of the to-be-projected image, wherein the phase spatial light modulator 54 is configured to modulate the laser light emitted by the laser 53 according to the brightness information of the to-be-projected image to obtain the first modulated illumination light.

Thereafter, the first modulated illumination light is emitted onto the fluorescent pink wheel 55 to generate red light, green light and blue light, and the generated red light, green light and blue light are divided into red light path, green light path and blue light path under the action of the beam splitter 56. In the red light path, the red light is transmitted to the first amplitude modulation unit 58 under the optical action of the first lens 57, and is modulated by the first amplitude modulation unit 38 according to the red information of the image to be projected to obtain red image light to be projected. In the green light path, the green light is transmitted to the second amplitude modulation unit 60 under the optical action of the second lens 59, and is modulated by the second amplitude modulation unit 60 according to the green information of the image to be projected to obtain green image light to be projected. In the blue light path, the blue light is transmitted to the third amplitude modulation unit 62 under the optical action of the third lens 61, and is modulated by the third amplitude modulation unit 62 according to the blue information of the image to be projected to obtain a blue image to be projected. The red image light to be projected, the green image light to be projected and the blue image light to be projected are combined by the light combiner 63 , and finally projected onto the projection screen 65 simultaneously or sequentially by the projection lens 64 .

It can be understood that the phase spatial light modulator 54 here is a liquid crystal on silicon spatial light modulator, and the fluorescent pink wheel 55 can be a yellow fluorescent pink wheel.

The projection system 500 further includes a light combiner 63 for guiding the red image light to be projected, the green image light to be projected and the blue image light to be projected onto the same optical path.

It can be understood that the structure composed of the fluorescent pink wheel 55 , the beam splitter 56 , the first lens 57 , the second lens 59 and the third lens 61 in the projection system 500 can be regarded as the aforementioned optical components.

It can be understood that the lenses described in FIG. 14 to FIG. 16 may include one or more lenses of the same type or different types, so as to perform light processing on the first modulated illumination light to realize the adjustment of the broadening.

In summary, compared with the prior art, the phase spatial light modulator of the projection device provided by the present invention can obtain the first modulated illumination light by modulating the laser light according to the image to be projected after receiving the laser light emitted by the laser light source, and the modulated first modulated illumination light includes light spots and dark areas between the light spots. Thereafter, optical components are used to perform optical processing on the received first modulated illumination light to obtain second modulated illumination light, and the obtained second modulated illumination light satisfies the need to widen the light spots of the first modulated illumination light, so that each light spot covers the dark area between the light spots, and satisfies the condition that the overlapping area of each light spot after widening is not greater than a preset threshold value, thereby facilitating the provision of illumination light with relatively uniform light distribution. At the same time, since the brightness of the second modulated illuminating light is relatively uniform, when it is irradiated to the amplitude spatial light modulator of the projection device, the transition between the dark part and the bright part of the image light to be projected obtained after the amplitude spatial light modulation is relatively smooth, which can achieve a better local darkening effect, and is conducive to improving the viewing comfort of the human eye and helping to improve the visual experience of the audience.

Further, by using the phase spatial light modulator to modulate the illumination light, the first modulated illumination light with a corresponding brightness distribution can be modulated in real time according to the image to be projected, which can realize the projection of a high-dynamic range (High-Dynamic Range, HDR) image, and can relatively guarantee the brightness of the projected image, which is conducive to improving the performance of the projection device.

Furthermore, on the basis of the optical components including the fluorescent pink wheel and the corresponding lens, the dark area reserved by the interference pattern can effectively reduce the influence of the light spot on the uniformity of the brightness distribution during the widening process, which is conducive to achieving a better high dynamic range image projection effect.

The above is only the embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process conversion made by using the description of the present invention and the contents of the accompanying drawings, or directly or indirectly used in other related technical fields, is also included in the scope of patent protection of the present invention.

Claims (10)

1. A method for controlling a projection device, comprising the following steps: S101: controlling the laser light source to output laser; S102: Modulate the received laser light according to the image to be projected to obtain a first modulated illumination light, where the first modulated illumination light includes light spots and dark areas between the light spots; S103: Widen the light spot of the first modulated illumination light so that the light spot extends to the dark area, so as to obtain the second modulated illumination light, and the overlapping area between the light spots of the second modulated illumination light is not greater than a preset threshold. 2. The control method according to claim 1, wherein the step S102 comprises: modulating the received laser light according to the brightness information of the image to be projected to obtain a first modulated illumination light, the first modulated illumination light having an illumination light field with a corresponding brightness distribution. 3. The control method according to claim 2, wherein the brightness of the first modulated illumination light and the brightness information of the image to be projected can satisfy a preset relationship, and the preset relationship includes any of the following: The brightness of the first modulated illumination light is equal to the maximum brightness of the pixel of the image to be projected; The brightness of the first modulated illumination light is equal to the maximum brightness of pixels in the preset area of the image to be projected; and The brightness of the first modulated illumination light is equal to the average brightness of each pixel in the image to be projected. 4. The control method according to any one of claims 1-3, wherein the step S103 comprises: widening the light spot of the first modulated illumination light by a wavelength conversion element to expand the light spot to the dark area, thereby obtaining a first-level second modulated illumination light, and the overlapping area between the light spots of the first-level second modulated illumination light is not greater than a preset threshold. 5. The control method according to claim 4, wherein the step S103 further comprises: widening the light spot of the first-level second modulated illumination light through a lens unit to expand the light spot to the dark area, thereby obtaining the second-level second modulated illumination light, and the overlapping area between the light spots of the second-level second modulated illumination light is not greater than the preset threshold. 6. The control method according to claim 1, characterized in that, after the step S103, further comprising the following steps: S104: Modulate the second modulated illumination light to obtain image light to be projected. 7. The control method according to claim 6, wherein the step S104 comprises: the second modulated illumination light includes blue second modulated illumination light, red second modulated illumination light and green second modulated illumination light, and the blue second modulated illumination light, the red second modulated illumination light and the green second modulated illumination light are modulated in time sequence to obtain the blue image light to be projected, the red image light to be projected and the green image light to be projected in time sequence. 8. The control method according to claim 6, wherein the step S104 comprises: the second modulated illumination light includes blue second modulated illumination light, red second modulated illumination light and green second modulated illumination light, simultaneously modulating the red second modulated illumination light and the green second modulated illumination light to simultaneously obtain red image light to be projected and green image light to be projected, and time-divisionally modulating the blue second modulated illumination light to obtain blue image light to be projected. 9. The control method according to claim 6, wherein the step S104 comprises: the second modulated illumination light includes blue second modulated illumination light, red second modulated illumination light, and green second modulated illumination light, and simultaneously modulates the blue second modulated illumination light, the red second modulated illumination light, and the green second modulated illumination light to simultaneously obtain blue image light to be projected, red image light to be projected, and green image light to be projected. 10. A projection device, characterized in that the method according to any one of claims 1-9 is used.