Light conversion device, micro-projection system, method thereof, and near-eye display device

Abstract

A light conversion device and a micro-projection system and a method thereof and a near-eye display device. The light conversion device is used to convert input monochromatic light into a first output monochromatic light and a second output monochromatic light of different colors, so that the micro-projection system can use a monochromatic light source to realize the projection of a color image. The light conversion device includes a light modulation component, a first quantum dot layer and a second quantum dot layer. The light modulation component has a first optical path, a second optical path and a third optical path that do not completely overlap, and is used to modulate the input monochromatic light so that the input monochromatic light propagates along the first optical path, the second optical path and the third optical path respectively. The first quantum dot layer is correspondingly located in the first optical path, and is used to convert the input monochromatic light propagating along the first optical path into the first output monochromatic light. The second quantum dot layer is correspondingly located in the second optical path, and is used to convert the input monochromatic light propagating along the second optical path into the second output monochromatic light.

Description

Technical Field

[0001] The present invention relates to the field of projection technology, and in particular to a light conversion device, a micro-projection system and a method thereof, and a near-eye display device. Background Art

[0002] With the continuous development of projection display technology, in the fields of augmented reality (AR) and virtual reality (VR), the image signal source used by wearable micro-projection systems, in addition to LCOS, DLP, and OLED, the scanning projection technology that uses laser sources as image signal input is also gaining more and more attention. Figure 1 As shown, most of the current color scanning micro-projection systems 1P generally include RGB three-color laser emitters 10P (such as three monochromatic laser emitters), three independent collimation systems 20P (such as three collimating lenses, etc.), a color combining system 30P (such as three separate parallel color combining mirrors or X-Cube type color combining prisms, etc.), a MEMS scanning mirror 40P, a projection lens 50P, and a driving control module 60P. The driving control module 60P controls the RGB three-color laser light source 10P to emit three paths of monochromatic light, and after the three paths of monochromatic light are collimated by the collimation system 20P, they are combined into one path of combined color light by the color combining system 30P, and then the driving control module 60P controls the MEMS scanning mirror 40P to rotate, so as to scan the combined color light into a two-dimensional image through the MEMS scanning mirror 40P, and finally project it through the projection lens 50P to form an image.

[0003] However, since the existing color scanning micro-projection system 1P needs to be equipped with three laser emitters of different colors, and the temperature control and heat dissipation system of the laser emitter has high requirements, each laser emitter of the existing color scanning micro-projection system 1P also needs to be equipped with a corresponding temperature control system to reduce wavelength drift, which is not only not conducive to the overall compactness of the system, but also the three laser emitters of different colors work at the same time, which requires higher heat dissipation performance of the system, resulting in a more complex system structure. Of course, the high coherence of the laser source itself will also lead to increased speckle in the projected image, reduce image quality, and thus affect the visual effect.

[0004] In addition, since the light source output characteristics of laser emitters of different colors in the existing color scanning micro-projection system 1P are different, the collimation system of each laser emitter of the existing color scanning micro-projection system 1P needs to be designed separately, which increases the difficulty of designing the collimation system, and the independently assembled collimation system and color combination system will also reduce the accuracy of the overall optical path of the system. In addition, the existing color scanning micro-projection system 1P is equipped with three independent collimation systems, plus a color combination module, which makes the overall size of the system larger and heavier. Summary of the invention

[0005] An advantage of the present invention is that it provides a light conversion device and a micro-projection system and method thereof and a near-eye display device, which can use a monochromatic light source to achieve the projection of a color image, thereby helping to reduce the volume and weight of the micro-projection system.

[0006] Another advantage of the present invention is to provide a light conversion device and a micro-projection system and a method thereof and a near-eye display device. In one embodiment of the present invention, the light conversion device converts monochromatic light into colored light by combining a modulated grating and a total reflection waveguide to reduce the number of light sources, which is beneficial to reducing the volume and weight of the micro-projection system.

[0007] Another advantage of the present invention is to provide a light conversion device and a micro-projection system and a method thereof and a near-eye display device. In one embodiment of the present invention, the light conversion device can integrate the RGB three-color light paths together without deviation, which helps to improve the projection quality of the micro-projection system.

[0008] Another advantage of the present invention is to provide a light conversion device and a micro-projection system and a method thereof and a near-eye display device. In one embodiment of the present invention, the micro-projection system can realize the projection of color images while using a monochromatic light source, so that the volume and weight of the micro-projection system are greatly reduced.

[0009] Another advantage of the present invention is that it provides a light conversion device and a micro-projection system and a method thereof and a near-eye display device. In one embodiment of the present invention, the light conversion device can convert the laser light emitted by a monochromatic laser source into fluorescence to avoid coherence problems, which helps to reduce the speckle phenomenon of the projected image.

[0010] Another advantage of the present invention is to provide a light conversion device and a micro-projection system and a method thereof and a near-eye display device. In one embodiment of the present invention, the light conversion device helps to realize a micro-projection system with small size, light weight and high imaging quality.

[0011] Another advantage of the present invention is that it provides a light conversion device and a micro-projection system and a method and a near-eye display device. In one embodiment of the present invention, the light conversion device can make light enter and exit from the same side of the light conversion device, so that the structure of the light conversion device is more compact. At the same time, it also helps to reduce the distribution spacing of the modulated grating in the light conversion device, thereby reducing the volume of the light conversion device.

[0012] Another advantage of the present invention is to provide a light conversion device and a micro-projection system and a method thereof and a near-eye display device, wherein, in order to achieve the above-mentioned purpose, no expensive materials or complex structures are required in the present invention. Therefore, the present invention successfully and effectively provides a solution, not only providing a simple light conversion device and a micro-projection system and a method thereof and a near-eye display device, but also adding the light conversion device and the micro-projection system and a method thereof and a near-eye display device.

[0013] In order to achieve at least one of the above-mentioned invention objects or other objects and advantages, the present invention provides a light conversion device for converting input monochromatic light into a first output monochromatic light and a second output monochromatic light of different colors, comprising:

[0014] an optical modulation component, wherein the optical modulation component has a first optical path, a second optical path and a third optical path that are not completely overlapped, and is used to modulate the input monochromatic light so that the input monochromatic light propagates along the first optical path, the second optical path and the third optical path respectively;

[0015] a first quantum dot layer, wherein the first quantum dot layer is correspondingly located in the first optical path of the light modulation component, and is used to convert the input monochromatic light propagating along the first optical path into the first output monochromatic light; and

[0016] A second quantum dot layer, wherein the second quantum dot layer is correspondingly located in the second optical path of the light modulation component, and is used to convert the input monochromatic light propagating along the second optical path into the second output monochromatic light.

[0017] In one embodiment of the present invention, the first optical path, the second optical path and the third optical path of the optical modulation component are switched on and off in a time-sharing manner.

[0018] In one embodiment of the present invention, the first optical path, the second optical path and the third optical path of the optical modulation component are partially overlapped end to end.

[0019] In one embodiment of the present invention, the optical modulation component includes at least one optical modulation unit, wherein the optical modulation unit includes a first total reflection substrate layer and a modulation grating layer, and the optical modulation unit has a total reflection optical path and a through optical path that are switched on and off in time division, wherein the modulation grating layer is superimposed on the first total reflection substrate layer, and the modulation grating layer is used to adjust the state of the optical modulation unit so that the optical modulation unit switches between a first state and a second state, wherein when the optical modulation unit is in the first state, the through optical path of the optical modulation unit is switched on and the total reflection optical path of the optical modulation unit is switched off; and when the optical modulation unit is in the second state, the through optical path of the optical modulation unit is switched off and the total reflection optical path of the optical modulation unit is switched on.

[0020] In one embodiment of the present invention, the modulation grating layer includes a first modulation grating and a second modulation grating arranged side by side, wherein the total reflection light path of the light modulation unit passes through the first modulation grating and the second modulation grating in sequence under the action of total reflection of the first total reflection substrate layer, so as to open or open the total reflection light path through the first modulation grating and the second modulation grating; wherein the through light path of the light modulation unit only passes through the first modulation grating under the action of transmission of the first total reflection substrate layer, so as to open or open the through light path through the first modulation grating.

[0021] In one embodiment of the present invention, the first and second modulation gratings of the modulation grating layer both have a transmission state and a diffraction state, which are used to switch the states of the first and second modulation gratings by adjusting the applied voltage, thereby regulating the state of the light modulation unit.

[0022] In one embodiment of the present invention, the light modulation unit has an input area, a first output area and a second output area, wherein the input area and the first output area both correspond to the first modulation grating of the modulation grating layer, and the second output area corresponds to the second modulation grating of the modulation grating layer.

[0023] In one embodiment of the present invention, the light modulation unit further comprises a second total reflection substrate layer, wherein the second total reflection substrate layer is stacked on the modulation grating layer, and the modulation grating layer is located between the first total reflection substrate layer and the second total reflection substrate layer.

[0024] In one embodiment of the present invention, the input area and the second output area of ​​the light modulation unit are arranged side by side on the second total reflection substrate layer of the light modulation unit, and the first output area is correspondingly arranged on the first total reflection substrate layer of the light modulation unit.

[0025] In one embodiment of the present invention, the first modulation grating and the second modulation grating are closely arranged between the first total reflection substrate and the second total reflection substrate, so that the total reflection light path of the light modulation unit is turned by total reflection only once in the first total reflection substrate layer.

[0026] In one embodiment of the present invention, the first modulation grating and the second modulation grating are arranged at intervals between the first total reflection substrate layer and the second total reflection substrate layer to form an air gap between the first modulation grating and the second modulation grating, so that the total reflection light path of the optical modulation unit can be turned by an odd number of total reflections within the first total reflection substrate layer.

[0027] In one embodiment of the present invention, the modulation grating layer further includes a light-transmitting spacer, wherein the light-transmitting spacer is arranged between the first modulation grating and the second modulation grating, and the total reflection light path of the light modulation unit passes through the light-transmitting spacer an even number of times, so that the total reflection light path is turned by total reflection in the first total reflection substrate layer and the second total reflection substrate layer respectively.

[0028] In one embodiment of the present invention, the first output region and the second output region of the light modulation unit are arranged side by side on the second total reflection substrate layer of the light modulation unit, and the input region is correspondingly arranged on the first total reflection substrate layer of the light modulation unit.

[0029] In one embodiment of the present invention, the modulation grating layer further includes a light-transmitting spacer, wherein the light-transmitting spacer is arranged between the first modulation grating and the second modulation grating, and the total reflection light path of the light modulation unit passes through the light-transmitting spacer an odd number of times, so that the total reflection light path is turned by total reflection in the first total reflection substrate layer and the second total reflection substrate layer respectively.

[0030] In one embodiment of the present invention, the material of the light-transmitting spacer is the same as that of the first and second modulation gratings.

[0031] In one embodiment of the present invention, the material of the light-transmitting spacer is the same as that of the first and second total-reflection substrate layers, and the light-transmitting spacer integrally connects the first and second total-reflection substrate layers.

[0032] In one embodiment of the present invention, the at least one light modulation unit of the light modulation component includes a first light modulation unit, a second light modulation unit and a third light modulation unit, wherein the first light modulation unit, the second light modulation unit and the third light modulation unit are stacked together in sequence accordingly, wherein the first quantum dot layer is arranged between the first light modulation unit and the second light modulation unit, and the second quantum dot layer is arranged between the second light modulation unit and the third light modulation unit.

[0033] In one embodiment of the present invention, the first quantum dot layer is correspondingly arranged in the second output area or the first output area of ​​the first light modulation unit, and the second quantum dot layer is correspondingly arranged in the second output area or the first output area of ​​the second light modulation unit.

[0034] In one embodiment of the present invention, the at least one light modulation unit of the light modulation component includes a first light modulation unit, a second light modulation unit and a third light modulation unit, wherein the first light modulation unit, the second light modulation unit and the third light modulation unit are stacked together in sequence accordingly, wherein the first quantum dot layer is arranged between the first light modulation unit and the second light modulation unit, and the second quantum dot layer is arranged between the second light modulation unit and the third light modulation unit.

[0035] In one embodiment of the present invention, the first quantum dot layer is correspondingly arranged in the second output area or the input area of ​​the first light modulation unit, and the second quantum dot layer is correspondingly arranged in the second output area or the input area of ​​the second light modulation unit.

[0036] In one embodiment of the present invention, the at least one light modulation unit of the light modulation component includes a second light modulation unit and a third light modulation unit, and the light modulation component further includes a total reflection unit, wherein the total reflection unit, the second light modulation unit and the third light modulation unit are stacked together in sequence, wherein the first quantum dot layer is arranged between the total reflection unit and the second light modulation unit, and the second quantum dot layer is arranged between the second light modulation unit and the third light modulation unit.

[0037] In one embodiment of the present invention, the total reflection unit includes a waveguide element, a coupling element and a coupling element, wherein the coupling element and the coupling element are arranged side by side on the same side of the waveguide element, and the coupling element and the coupling element correspond to the first modulation grating and the second modulation grating in the optical modulation unit respectively.

[0038] In one embodiment of the present invention, the first quantum dot layer is correspondingly arranged in the out-coupling element or the in-coupling element of the total reflection unit, and the second quantum dot layer is correspondingly arranged in the second output area or the input area of ​​the second light modulation unit.

[0039] In one embodiment of the present invention, the total reflection unit is a total reflection prism, and the inclined surface of the total reflection prism faces the second light modulation unit, and the first quantum dot layer is correspondingly arranged on the inclined surface of the total reflection prism.

[0040] In one embodiment of the present invention, the light modulation component further includes a coupling element, wherein the coupling element is correspondingly arranged in the input area of ​​the light modulation unit, and the coupling element is used to couple the input monochromatic light vertically or obliquely into the light modulation unit.

[0041] In one embodiment of the present invention, the first light path, the second light path and the third light path of the light modulation component are parallel to each other.

[0042] In one embodiment of the present invention, the optical modulation component includes an optical modulation unit, wherein the optical modulation unit includes a second total reflection substrate layer and a modulation grating layer, wherein the modulation grating layer is superimposed on the second total reflection substrate layer, and the modulation grating layer includes a first modulation grating, a second modulation grating and a third modulation grating arranged side by side, wherein the first modulation grating is located in the first optical path of the optical modulation component for switching on or off the first optical path; wherein the second modulation grating is located in the second optical path of the optical modulation component for switching on or off the second optical path; wherein the third modulation grating is located in the third optical path of the optical modulation component for switching on or off the third optical path.

[0043] In one embodiment of the present invention, the first quantum dot layer and the second quantum dot layer are arranged side by side on the second total reflection substrate layer, and the first quantum dot layer and the second quantum dot layer correspond to the first modulation grating and the second modulation grating respectively.

[0044] In one embodiment of the present invention, the light modulation unit further includes a first total reflection substrate layer, wherein the first total reflection substrate layer is stacked on the modulation grating layer, and the modulation grating layer is located between the first total reflection substrate layer and the second total reflection substrate layer.

[0045] In one embodiment of the present invention, the light modulation component further includes a light absorption layer, wherein the light absorption layer is disposed on a side surface of the light modulation unit.

[0046] In one embodiment of the present invention, the first quantum dot layer is a red quantum dot layer, and the second quantum dot layer is a green quantum dot layer.

[0047] In one embodiment of the present invention, the light conversion device further includes a third quantum dot layer, wherein the third quantum dot layer is correspondingly arranged in the third optical path of the light modulation component, and is used to convert the input monochromatic light propagating along the third optical path into a third output monochromatic light of a different color.

[0048] In one embodiment of the present invention, the third quantum dot layer is a blue quantum dot layer.

[0049] According to another aspect of the present invention, the present invention also provides a micro-projection system, comprising:

[0050] a monochromatic light source, wherein the monochromatic light source is configured to emit input monochromatic light having a predetermined color;

[0051] a light conversion device, wherein the light conversion device is used to convert the input monochromatic light from the monochromatic light source into a plurality of output monochromatic lights with different colors;

[0052] a scanning unit, wherein the scanning unit is used to scan the output monochromatic light from the light conversion device into color image light; and

[0053] A projection unit, wherein the projection unit is used to project the color image light from the scanning unit to form an image.

[0054] In one embodiment of the present invention, the light conversion device includes a light modulation component, a first quantum dot layer and a second quantum dot layer, wherein the light modulation component has a first optical path, a second optical path and a third optical path that do not completely overlap, and is used to modulate the input monochromatic light so that the input monochromatic light propagates along the first optical path, the second optical path and the third optical path respectively; wherein the first quantum dot layer is correspondingly located in the first optical path of the light modulation component, and is used to convert the input monochromatic light propagating along the first optical path into a first output monochromatic light of a different color; wherein the second quantum dot layer is correspondingly located in the second optical path of the light modulation component, and is used to convert the input monochromatic light propagating along the second optical path into a second output monochromatic light of a different color.

[0055] In one embodiment of the present invention, the light conversion device further includes a third quantum dot layer, wherein the third quantum dot layer is correspondingly arranged in the third optical path of the light modulation component, for converting the input monochromatic light propagating along the third optical path into a third output monochromatic light of a different color.

[0056] In one embodiment of the present invention, the monochromatic light source is a blue laser source.

[0057] In one embodiment of the present invention, the monochromatic light source is an ultraviolet laser source.

[0058] In one embodiment of the present invention, the micro-projection system further includes a driving control unit, wherein the driving control unit is communicatively connected to the monochromatic light source, the light conversion device and the scanning unit, respectively, and is used to adjust the emission intensity of the monochromatic light source to emit the input monochromatic light with a desired light intensity, adjust the conversion state of the light conversion device to convert the input monochromatic light into the output monochromatic light with a desired color, and adjust the scanning angle of the scanning unit to scan the output monochromatic light into a desired color image light.

[0059] According to another aspect of the present invention, the present invention also provides a photoconversion method, comprising the steps of:

[0060] Modulating input monochromatic light so that the input monochromatic light propagates along a first optical path, a second optical path, and a third optical path that do not completely overlap;

[0061] converting the input monochromatic light propagating along the first optical path into a first output monochromatic light of a different color; and

[0062] The input monochromatic light propagating along the second optical path is converted into a second output monochromatic light of a different color.

[0063] In one embodiment of the present invention, the light conversion method further comprises the steps of:

[0064] The input monochromatic light propagating along the third optical path is directly used as the third output monochromatic light.

[0065] In one embodiment of the present invention, the light conversion method further comprises the steps of:

[0066] The input monochromatic light propagating along the third optical path is converted into a third output monochromatic light of a different color.

[0067] In one embodiment of the present invention, the light conversion method further comprises the steps of:

[0068] The first optical path, the second optical path and the third optical path are switched on and off in a time-sharing manner, so as to provide the first output monochromatic light, the second output monochromatic light and the third output monochromatic light with different colors in a time-sharing manner.

[0069] According to another aspect of the present invention, the present invention also provides a micro-projection method, comprising the steps of:

[0070] emitting input monochromatic light having a predetermined color;

[0071] converting the input monochromatic light into a plurality of output monochromatic lights having different colors;

[0072] scanning the output monochromatic light into color image light; and

[0073] The color image light is projected to form an image.

[0074] In one embodiment of the present invention, the step of converting the input monochromatic light into a plurality of output monochromatic lights having different colors comprises the steps of:

[0075] Modulating the input monochromatic light so that the input monochromatic light propagates along a first optical path, a second optical path, and a third optical path that do not completely overlap;

[0076] converting the input monochromatic light propagating along the first optical path into a first output monochromatic light of a different color; and

[0077] The input monochromatic light propagating along the second optical path is converted into a second output monochromatic light of a different color.

[0078] According to another aspect of the present invention, the present invention also provides a near-eye display device, comprising:

[0079] a near-eye display device body; and

[0080] At least one micro-projection system, wherein the micro-projection system is correspondingly arranged on the near-eye display device body, and is used to provide image light for the near-eye display device body; wherein the micro-projection system comprises:

[0081] a monochromatic light source, wherein the monochromatic light source is configured to emit input monochromatic light having a predetermined color;

[0082] a light conversion device, wherein the light conversion device is used to convert the input monochromatic light from the monochromatic light source into a plurality of output monochromatic lights with different colors;

[0083] a scanning unit, wherein the scanning unit is used to scan the output monochromatic light from the light conversion device into color image light; and

[0084] A projection unit, wherein the projection unit is used to project the color image light from the scanning unit to form an image.

[0085] Further objects and advantages of the present invention will be fully apparent from an understanding of the following description and the accompanying drawings.

[0086] These and other objects, features and advantages of the present invention will be more fully understood from the following detailed description, accompanying drawings and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0087] Figure 1 It is a system schematic diagram of a color scanning micro-projection system in the prior art.

[0088] Figure 2 is a system schematic diagram of a micro-projection system according to a first embodiment of the present invention.

[0089] Figure 3 A schematic structural diagram of a light conversion device of the micro-projection system according to the first embodiment of the present invention is shown.

[0090] Figure 4 A schematic diagram showing the operation of the light conversion device according to the first embodiment of the present invention is shown.

[0091] Figure 5 A schematic structural diagram of a light modulation unit of the light conversion device according to the first embodiment of the present invention is shown.

[0092] Fig. 6A and Figure 6B A schematic diagram showing the state of the modulation grating in the light modulation unit according to the first embodiment of the present invention is shown.

[0093] Figure 7 A modified example of the light modulation unit according to the first embodiment of the present invention is shown.

[0094] Figure 8 A first variant implementation of the light conversion device according to the first embodiment of the present invention is shown.

[0095] Fig. 9 A second variant implementation of the light conversion device according to the first embodiment of the present invention is shown.

[0096] Fig.10 A third variant implementation of the light conversion device according to the first embodiment of the present invention is shown.

[0097] Fig.11 is a system schematic diagram of a micro-projection system according to a second embodiment of the present invention.

[0098] Fig.12 A schematic diagram showing the operation of the light conversion device of the micro-projection system according to the second embodiment of the present invention is shown.

[0099] Fig.13 A schematic structural diagram of a light modulation unit of the light conversion device according to the second embodiment of the present invention is shown.

[0100] Fig.14A A first modified example of the light modulation unit according to the second embodiment of the present invention is shown.

[0101] Fig. 14B A second modified example of the light modulation unit according to the second embodiment of the present invention is shown.

[0102] Fig.15 A first variant implementation of the light conversion device according to the second embodiment of the present invention is shown.

[0103] Fig.16 A second variant implementation of the light conversion device according to the second embodiment of the present invention is shown.

[0104] Fig.17A and Fig. 17B A third variant implementation of the light conversion device according to the second embodiment of the present invention is shown.

[0105] Fig.18 is a system schematic diagram of a micro-projection system according to a third embodiment of the present invention.

[0106] Fig.19 A schematic diagram showing the operation of the light conversion device of the micro-projection system according to the third embodiment of the present invention is shown.

[0107] Fig. 20 is a system schematic diagram of a micro-projection system according to a fourth embodiment of the present invention.

[0108] Fig.21 A schematic diagram showing the operation of the light conversion device of the micro-projection system according to the fourth embodiment of the present invention is shown.

[0109] Fig. 22 An example of a near-eye display device according to the present invention is shown.

[0110] Fig.23 A schematic flow chart of a light conversion method according to an embodiment of the present invention is shown.

[0111] Fig.24 A schematic flow chart of a micro-projection method according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0112] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art can think of other obvious variations. The basic principles of the present invention defined in the following description can be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not deviate from the spirit and scope of the present invention.

[0113] Those skilled in the art should understand that, in the disclosure of the present invention, the orientation or position relationship indicated by the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. are based on the orientation or position relationship shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0114] In the present invention, the term "one" in the claims and the specification should be understood as "one or more", that is, in one embodiment, the number of an element can be one, while in another embodiment, the number of the element can be multiple. Unless it is clearly indicated in the disclosure of the present invention that the number of the element is only one, the term "one" cannot be understood as unique or single, and the term "one" cannot be understood as a limitation on the quantity.

[0115] In the description of the present invention, it should be understood that "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through a medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0116] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0117] like Figure 1 As shown, since the existing color scanning micro-projection system 1P needs to be equipped with RGB three-color laser emitters 10P, and the temperature control and heat dissipation system of the laser emitter has high requirements, each laser emitter 10P of the existing color scanning micro-projection system 1P also needs to be equipped with a corresponding temperature control system to reduce wavelength drift, which is not only not conducive to the overall compactness of the system, but also the three different colors of laser emitters work at the same time, which requires higher heat dissipation performance of the system, resulting in a more complex system structure. Of course, the high coherence of the laser source itself will also lead to increased speckle in the projected image, reduce image quality, and thus affect the visual effect.

[0118] In addition, since the light source output characteristics of the RGB three-color laser emitter 10P in the existing color scanning micro-projection system 1P are different, the collimation system 20P of each laser emitter 10P of the existing color scanning micro-projection system 1P needs to be designed separately, which increases the design difficulty of the collimation system 20P, and the independently assembled collimation system 20P and the color combination system 30P will also reduce the accuracy of the overall optical path of the system. In particular, the existing color scanning micro-projection system 1P is equipped with the RGB three-color laser emitter 10P, the three independent collimation systems 20P, and the module 30P, which makes the overall size of the system larger and the weight heavier. Therefore, in order to solve the above problems, the present invention provides a light conversion device and a micro-projection system and a method thereof and a near-eye display device.

[0119] Reference to the attached drawings of the specification Figures 2 to 5 As shown, a micro-projection system according to a first embodiment of the present invention is illustrated. Specifically, as Figure 2As shown, the micro-projection system 1 includes a monochromatic light source 10, a light conversion device 20, a scanning unit 30 and a projection unit 40. The monochromatic light source 10 is used to emit an input monochromatic light 110 having a predetermined color. The light conversion device 20 is used to convert the input monochromatic light 110 from the monochromatic light source 10 into a plurality of output monochromatic lights 120 of different colors. The scanning unit 30 is used to scan the output monochromatic light 120 from the light conversion device 20 into a color image light. The projection unit 40 is used to project the color image light from the scanning unit 30 to form an image. It can be understood that, compared with the existing color scanning micro-projection system 1P, the number of light sources of the micro-projection system 1 of the present invention is greatly reduced, and the projection of a color image can be achieved by using only a single monochromatic light source, which helps to reduce the volume and weight of the micro-projection system.

[0120] Furthermore, in the first embodiment of the present invention, the scanning unit 30 is preferably implemented as a MEMS scanning mirror; the projection unit 40 is preferably implemented as an imaging lens group. Of course, the scanning unit 30 and the projection unit 40 of the present invention can also be implemented as other types of devices or products, which will not be described in detail in the present invention.

[0121] It is worth mentioning that according to the above first embodiment of the present invention, Figure 3 and Figure 4As shown, the light conversion device 20 of the micro-projection system 1 may include a light modulation component 21, a first quantum dot layer 22, and a second quantum dot layer 23. The light modulation component 21 has a first light path 201, a second light path 202, and a third light path 203 that are not completely overlapped, and is used to modulate the input monochromatic light 110 from the monochromatic light source 10 to form the first light path 201, the second light path 202, and the third light path 203 in the light modulation component 21, so that the input monochromatic light 110 incident on the light modulation component 21 can propagate along the first light path 201, the second light path 202, and the third light path 203 in the light modulation component 21. The first quantum dot layer 22 is correspondingly located in the first optical path 201 of the optical modulation component 21, and is used to convert the input monochromatic light 110 propagating along the first optical path 201 into a first output monochromatic light 121, so that the first output monochromatic light 121 is emitted from the optical conversion device 20 along the first optical path 201. The second quantum dot layer 23 is correspondingly arranged in the second optical path 202 of the optical modulation component 21, and is used to convert the input monochromatic light 110 propagating along the first optical path 201 into a second output monochromatic light 122, so that the second output monochromatic light 122 is emitted from the optical conversion device 20 along the second optical path 202. It can be understood that the incomplete overlap mentioned in the present invention refers to complete non-overlap (i.e., complete separation) or partial overlap (i.e., partial separation).

[0122] It is worth noting that in this first embodiment of the present invention, Figure 4 As shown, since no quantum dot layer is provided on the third optical path 203 in the optical modulation component 21, the input monochromatic light 110 propagating along the third optical path 203 will not be converted and directly serves as the third output monochromatic light 123, so as to be emitted from the optical conversion device 20 along the third optical path 203. In particular, the colors of the input monochromatic light 110, the first output monochromatic light 121, and the second output monochromatic light 122 in the present invention are different from each other, that is, the colors of the first output monochromatic light 121, the second output monochromatic light 122, and the third output monochromatic light 123 are different from each other, so that the monochromatic light source 10 and the optical conversion device 20 provide the scanning unit 30 with monochromatic light of three colors, so that the scanning unit 30 can scan into color image light, and then form a color image through the imaging unit 40.

[0123] It is worth mentioning that the quantum dots mentioned in the present invention (such as the materials of the first and second quantum dot layers 22 and 23) are a new type of luminescent nanomaterial, usually nanoparticles with a diameter of 2 to 20 nm, which can convert light of a lower wavelength (i.e., absorption spectrum) to a wavelength determined by its production size (i.e., emission spectrum). In other words, the wavelength of the emission spectrum of the materials of the first and second quantum dot layers 22 and 23 is longer than the wavelength of the absorption spectrum. For example, the first and second quantum dot layers 22 and 23 can convert blue light (or ultraviolet light) into green light and red light respectively. These characteristics depend on the chemical composition of the quantum dots and the size and shape of the quantum dots.

[0124] In addition, due to the quantum confinement effect, quantum dots of the same material but different sizes can emit light of different colors, and the smaller the size of the quantum dots, the greater the difference between the highest valence band and the lowest conduction band (i.e., a higher band gap), the emitted light is bluer or has higher energy, and the larger the size of the quantum dots, the redder or lower energy emitted light. Therefore, the present invention can select a blue laser source and corresponding red light quantum dots and green light quantum dots according to the RGB center wavelength of the desired color image source to provide color image light. At the same time, since the emitted light of the quantum dots is incoherent light, the light conversion device 20 of the present invention can reduce speckle in the optical path and improve the image projection quality.

[0125] Preferably, if Figure 2 and Figure 4 As shown, the monochromatic light source 10 is implemented as a blue laser source 11 for emitting blue light; that is, the input monochromatic light 110 and the third output monochromatic light 123 are preferably implemented as blue light. Correspondingly, the first quantum dot layer 22 is preferably implemented as a red quantum dot layer 221 for converting blue light into red light; that is, the first output monochromatic light 121 is preferably implemented as red light. At the same time, the second quantum dot layer 23 is preferably implemented as a green quantum dot layer 231 for converting blue light into green light; that is, the second output monochromatic light 122 is preferably implemented as green light. In this way, the light conversion device 20 of the above-mentioned first embodiment of the present invention can provide RGB three primary colors of light to the scanning unit 30 to realize color image scanning. It can be understood that in other examples of the present invention, the monochromatic light source 11, the first quantum dot layer 22 and the second quantum dot layer 23 can also be implemented as products that produce other color lights (such as non-three primary colors of light), which can also realize color image scanning.

[0126] More preferably, the red quantum dot layer 221 and the green quantum dot layer 231 may further include a blue filter film and a micro-nano resonant cavity in addition to the quantum dots, wherein the blue filter film is used to filter out blue light; and the micro-nano resonant cavity is used to maintain the collimation directionality and monochromaticity of the excitation light.

[0127] According to the above first embodiment of the present invention, Figure 3 and Figure 4 As shown, the first optical path 201, the second optical path 202 and the third optical path 203 of the optical modulation component 21 of the optical conversion device 20 are partially overlapped end to end, that is, the input segment and the output segment of the first optical path 201, the second optical path 202 and the third optical path 203 respectively overlap, and the middle segments of the first optical path 201, the second optical path 202 and the third optical path 203 are separated from each other. In this way, the monochromatic light source 10 (such as the blue laser source 11) only needs to provide one monochromatic light as the input monochromatic light 110, so that the input monochromatic light 110 can be incident on the light conversion device 20 along the same overlapping optical path, so as to be respectively propagated along the first optical path 201, the second optical path 202 and the third optical path 203 through the modulation of the light modulation component 21; at the same time, the input monochromatic light 110 propagating along the first optical path 201 (or the second optical path 202) is converted into the first output monochromatic light 121 (or the second output monochromatic light 122) by the first quantum dot layer 22 (or the second quantum dot layer 23) in the light conversion device 20; finally, the first output monochromatic light 121, the second output monochromatic light 122 and the third output monochromatic light 123 can all be emitted from the light conversion device 20 along the same overlapping optical path, so as to ensure that the monochromatic lights of different colors converted by the light conversion device 20 can be propagated to the scanning unit 30 along the same optical path, which helps to improve the color combination accuracy, and thus improve the projection quality of the micro-projection system 1.

[0128] In other words, in the above-mentioned first embodiment of the present invention, the light conversion device 20 can provide the scanning unit 30 with the output monochromatic light 120 of different colors (such as the first, second and third output monochromatic lights 121, 122, 123) along the same optical path. In this way, when the light conversion device 20 provides the scanning unit 30 with the output monochromatic light 120 of different colors along the same optical path, the output monochromatic lights 120 of different colors will not crosstalk with each other, so that the scanning unit 30 can receive the output monochromatic light 120 of different colors to scan into a color image. It can be understood that in order to clearly show that the light conversion device 20 converts the input monochromatic light 110 shown into the first, second and third output monochromatic lights 121, 122, 123 of different colors, although the present invention Figure 4The first, second and third optical paths 201, 202, 203 are represented by line segments of different line types separated from each other, but this is only for illustration and does not mean that the input segments and output segments of the first, second and third optical paths 201, 202, 203 are separated.

[0129] It is worth noting that since the wavelength of the emission spectrum of the quantum dot material is longer than the wavelength of the absorption spectrum, the first quantum dot layer 22 (such as the red quantum dot layer 221) can also convert the second output monochromatic light 122 (such as the green light) into the first output monochromatic light 121 (such as the red light), but the second quantum dot layer 23 (such as the green quantum dot layer 231) cannot convert the first output monochromatic light 121 (such as the red light) into the second output monochromatic light 122 (such as the green light). Therefore, the first quantum dot layer 22 of the present invention can only be arranged in the middle section of the first optical path 201 to prevent the second optical path 202 and the third optical path 203 from passing through the first quantum dot layer 22, so as to avoid the monochromatic light propagating along the second optical path 202 and the third optical path 203 from being converted into the first output monochromatic light 121 by the first quantum dot layer 22. In addition to being able to be arranged in the middle section of the second optical path 202, the second quantum dot layer 23 of the present invention can also be arranged in the overlapping section of the second optical path 202 and the first optical path 201 (such as a partial output section of the second optical path 202); at the same time, the third optical path 203 does not pass through the second quantum dot layer 23 to avoid the monochromatic light propagating along the third optical path 203 being converted into the second output monochromatic light 122 by the second quantum dot layer 23.

[0130] Preferably, in the above first embodiment of the present invention, as Figure 4 As shown, the first quantum dot layer 22 and the second quantum dot layer 23 are both located in the first optical path 201, and the position of the first quantum dot layer 22 on the first optical path 201 is closer to the starting point of the first optical path 201 (i.e., the input end of the first optical path 201) than the position of the second quantum dot layer 23 on the first optical path 201. In other words, the first quantum dot layer 22 is only located in the first optical path 201, wherein the second quantum dot layer 23 is simultaneously located in the first optical path 201 and the second optical path 202, and the position of the first quantum dot layer 22 on the first optical path 201 is forward than the position of the second quantum dot layer 23 on the first optical path 201, so that the input monochromatic light 110 propagating along the first optical path 201 first passes through the first quantum dot layer 22 to be converted into the first output monochromatic light 121, and then passes through the second quantum dot layer 23 to be emitted from the light conversion device 1.

[0131] It is worth noting that the micro-projection system 1 first provides the scanning unit 30 with monochromatic light of different colors as pixel light through the light conversion device 20, and then scans the multiple pixel lights into a two-dimensional image through the scanning unit 30 to form a color image light, and then projects through the projection unit 40 to form a color image, wherein each pixel point in the color image corresponds to the pixel light from the light conversion device 20. Since the scanning unit 30 can usually only scan one pixel point at a time, so that the scanning unit 30 scans all the pixel points in the two-dimensional image in a time-sharing manner, the light conversion device 20 of the micro-projection system 1 only needs to provide each pixel point with monochromatic light of the required color in a time-sharing manner, so as to realize the color image projection of the micro-projection system 1.

[0132] According to the above first embodiment of the present invention, Figure 4 As shown, the light modulation component 21 of the light conversion device 20 preferably has the first light path 201, the second light path 202 and the third light path 203 which are switched on and off in time, so that the light conversion device 20 can provide the first output monochromatic light 121, the second output monochromatic light 122 and the third output monochromatic light 123 in time. That is to say, when the first optical path 201 of the optical modulation component 21 is in the on state, the second optical path 202 and the third optical path 203 of the optical modulation component 21 are in the off state, so that the input monochromatic light 110 can only propagate along the first optical path 201 to be converted into the first output monochromatic light 121 via the first quantum dot layer 22 and be output; when the second optical path 202 of the optical modulation component 21 is in the on state, the first optical path 201 and the third optical path 203 of the optical modulation component 21 are in the off state, so that the input monochromatic light 110 can only propagate along the second optical path 202 to be converted into the second output monochromatic light 122 via the second quantum dot layer 23 and be output; when the third optical path 203 of the optical modulation component 21 is in the on state, the first optical path 201 and the second optical path 202 of the optical modulation component 21 are in the off state, so that the input monochromatic light 110 can only propagate along the third optical path 203 to be directly output as the third output monochromatic light 123. It is understandable that although the present invention Figure 4 The first, second and third optical paths 201, 202, 203 are drawn simultaneously, but the present invention uses line segments of different line types to represent the first, second and third optical paths 201, 202, 203 respectively, to indicate that the first, second and third optical paths 201, 202, 203 are switched on and off in different time periods.

[0133] Furthermore, if Figure 3 and Figure 5As shown, the light modulation component 21 of the light conversion device 20 may include at least one light modulation unit 210, wherein the light modulation unit 210 includes a first total reflection substrate layer 211, a second total reflection substrate layer 212 and a modulation grating layer 213, and the modulation grating layer 213 is stacked between the first total reflection substrate layer 211 and the second total reflection substrate layer 212, and is used to adjust the state of the light modulation unit 210 so that the light modulation unit 210 switches between a first state and a second state. The light modulation unit 210 has a through optical path 2101 and a total reflection optical path 2102, and the through optical path 2101 and the total reflection optical path 2102 correspond to a first output area 2103 and a second output area 2104 on the light modulation unit 210, respectively.

[0134] More specifically, when the modulation grating layer 213 is controlled so that the light modulation unit 210 is in the first state, the total reflection light path 2102 of the light modulation unit 210 is disconnected, and the through light path 2101 of the light modulation unit 210 is turned on, so that the input monochromatic light 110 can only propagate along the through light path 2101 to be emitted from the first output area 2103 of the light modulation unit 210; when the modulation grating layer 213 is controlled so that the light modulation unit 210 is in the second state, the total reflection light path 2102 of the light modulation unit 210 is turned on, and the through light path 2101 of the light modulation unit 210 is disconnected, so that the input monochromatic light 110 can only propagate along the total reflection light path 2102 to be emitted from the second output area 2104 of the light modulation unit 210.

[0135] Preferably, if Figure 5 As shown, the modulation grating layer 213 of the optical modulation unit 210 includes a first modulation grating 2131 and a second modulation grating 2132, wherein the first modulation grating 2131 and the second modulation grating 2132 are arranged side by side between the first total reflection substrate layer 211 and the second total reflection substrate layer 212, and the total reflection optical path 2102 of the optical modulation unit 210 passes through the first modulation grating 2131 and the second modulation grating 2132 in sequence under the action of total reflection of the first total reflection substrate layer 211 and the second total reflection substrate layer 212; and the projection optical path 2102 of the optical modulation unit 210 only passes through the first modulation grating 2131 and does not pass through the second modulation grating 2132 under the action of transmission of the first total reflection substrate layer 211 and the second total reflection substrate layer 212.

[0136] It is worth noting that Fig. 6A and Figure 6BAs shown, the first and second modulation gratings 2131, 2132 may be implemented as, but not limited to, holographic polymer dispersed liquid crystal gratings 2130. Liquid crystal (HPDLC) gratings) are made of polymer dispersed liquid crystal (PDLC) material. Since the polymer dispersed liquid crystal (PDLC) is usually a new type of optical material formed by dispersing liquid crystal droplets in a solid polymer macromolecular matrix, it has significant electrically controlled switching characteristics. Therefore, the grating made of the polymer dispersed liquid crystal (PDLC) material (such as the first and second modulation gratings 2131, 2132) can be electrically adjustable and can be used as a modulation grating (such as a holographic polymer dispersed liquid crystal grating 2130). It can be understood that the present invention can plate transparent electrodes (not shown in the figure) on the surfaces of the first and second total reflection substrate layers 211, 212, so as to apply a voltage to the modulation grating through the transparent electrodes, and then change the state of the modulation grating by adjusting the voltage of the transparent electrodes. Of course, in other examples of the present invention, the transparent electrode can also be directly set on the modulation grating by plating, pasting, plugging, etc., as long as the voltage can be applied to the modulation grating, and the present invention will not repeat it.

[0137] In other words, by adjusting the voltage applied to the modulation grating (such as the holographic polymer dispersed liquid crystal grating 2130), the modulation grating (such as the holographic polymer dispersed liquid crystal grating 2130) can operate in a diffraction state (i.e., the transmitted light is deflected relative to the incident light, and the directions of the two are different) and a transmission state (i.e., the transmitted light is not deflected relative to the incident light, and the directions of the two are consistent). For example, when the holographic polymer dispersed liquid crystal grating 2130 is in the diffraction state, the incident light vertically incident on the holographic polymer dispersed liquid crystal grating 2130 is diffracted to form diffracted light (such as the holographic polymer dispersed liquid crystal grating 2130) obliquely emitted from the holographic polymer dispersed liquid crystal grating 2130. Fig. 6A and the incident light obliquely incident on the holographic polymer dispersed liquid crystal grating 2130 is diffracted to form diffracted light (as shown) that exits the holographic polymer dispersed liquid crystal grating 2130 approximately vertically. Figure 6B When the holographic polymer dispersed liquid crystal grating 2130 is in the transmission state, the incident light vertically incident on the holographic polymer dispersed liquid crystal grating 2130 is transmitted to form a transmission light vertically incident on the holographic polymer dispersed liquid crystal grating 2130 (as shown in FIG. Fig. 6A and the incident light obliquely incident on the holographic polymer dispersed liquid crystal grating 2130 is transmitted to form a transmitted light obliquely emitted from the holographic polymer dispersed liquid crystal grating 2130 (as shown); Figure 6B shown).

[0138] Therefore, the present invention can optimize the parameters of the first and second modulation gratings 2131, 2132 according to a given wavelength (such as the wavelength of the input monochromatic light 110), so that the diffraction angle of the light vertically incident on the first and second modulation gratings 2131, 2132 is greater than the total reflection angle of the first and second total reflection substrate layers 211, 212 and the air interface; and the incident angle of the light obliquely incident on the first and second modulation gratings 2131, 2132 is greater than the total reflection angle of the first and second total reflection substrate layers 211, 212 and the air interface.

[0139] It is worth noting that the present invention can optimize the parameters of the first and second modulation gratings 2131, 2132 so that the output light efficiency of the first and second modulation gratings 2131, 2132 at a certain diffraction angle is 100%. That is to say, the first and second modulation gratings 2131, 2132 can be designed to switch between the diffraction state and the transmission state, thereby realizing the on-off function of the light path in the light conversion device 20.

[0140] For example, Figure 5 As shown, when the first and second modulation gratings 2131 and 2132 are both controlled to be in the diffraction state, the light vertically incident into the light modulation unit 210 will propagate along the total reflection optical path 2102 in the light modulation unit 210 to be vertically output from the second output area 2104 of the light modulation unit 210, so that the light modulation unit 210 is in the second state. When the first and second modulation gratings 2131 and 2132 are both controlled to be in the transmission state, the light vertically incident into the light modulation unit 210 will propagate along the through optical path 2101 in the light modulation unit 210 to be vertically output from the first output area 2103 of the light modulation unit 210, so that the light modulation unit 210 is in the first state.

[0141] It is worth noting that in the above first embodiment of the present invention, Figure 5As shown, the modulation grating layer 213 of the optical modulation unit 210 further includes a light-transmitting spacer 2133, wherein the light-transmitting spacer 2133 is arranged between the first modulation grating 2131 and the second modulation grating 2132, and the total reflection optical path 2102 passes through the light-transmitting spacer 2133, so that the light propagating along the total reflection optical path 2102 can pass through the first modulation grating 2131, the light-transmitting spacer 2133 and the second modulation grating 2132 in sequence. It can be understood that the total reflection angle of the interface between the light-transmitting partition 2133 and the first and second total reflection substrate layers 211 is greater than the total reflection angle of the interface between the first and second total reflection substrate layers 211 and the air, so as to prevent the input monochromatic light 110 from being totally reflected at the interface between the light-transmitting partition 2133 and the first and second total reflection substrate layers 211, so that the input monochromatic light 110 can pass through the light-transmitting partition 2133, so as to ensure that the light-transmitting partition 2133 will not cut off the total reflection light path 2102.

[0142] Preferably, the light-transmitting spacer 2133 of the modulation grating layer 213 of the optical modulation unit 210 is made of polymer dispersed liquid crystal material, that is, the material of the light-transmitting spacer 2133 is the same as the material of the first and second modulation gratings 2131 and 2132, so as to simplify the manufacturing process of the modulation grating layer 213 and reduce the cost of the modulation grating layer 213.

[0143] It is worth mentioning that Figure 7 As shown, in a modified example of the light modulation unit 210 of the present invention, the material of the light-transmitting spacer 2133' of the modulation grating layer 213' of the light modulation unit 210' can also be the same as the material of the first and second total reflection substrate layers 211, so that the light-transmitting spacer 2133 can be integrally connected with the first and second total reflection substrate layers 211 to eliminate the interface between the light-transmitting spacer 2133 and the first and second total reflection substrate layers 211, and completely avoid the input monochromatic light 110 from being totally reflected and reflected when passing through the light-transmitting spacer 2133, so as to reduce the light energy loss of the input monochromatic light 110, and help to maximize the light energy utilization rate of the light conversion device 20. It can be understood that the material of the first and second total reflection substrate layers 211 can be, but is not limited to, implemented as a light-transmitting material such as glass. Of course, in other examples of the present invention, the material of the light-transmitting spacer 2133' can also be the same as the material of the first and second total reflection substrate layers 211, as long as the refractive index of the light-transmitting spacer 2133' is also the same as the refractive index of the first and second total reflection substrate layers 211.

[0144] For example, in the above-mentioned first embodiment of the present invention, if Figure 5 As shown, the first output area 2103 and the second output area 2104 of the light modulation unit 210 are arranged side by side on the second total reflection substrate layer 212, and the first output area 2103 and the second output area 2104 correspond to the first modulation grating 2131 and the second modulation grating 2132 respectively, wherein the input area 2105 of the light modulation unit 210 is arranged on the first total reflection substrate layer 211, and the input area 2105 of the light modulation unit 210 corresponds to the first modulation grating 2131. It can be understood that the input area 2105 of the light modulation unit 210 is defined as the area on the light modulation unit 210 corresponding to the monochromatic light source 10, so that the input monochromatic light 110 from the monochromatic light source 10 can be incident into the light modulation unit 210 from the input area 2105.

[0145] In this way, Figure 5 As shown, the input monochromatic light 110 vertically incident into the light modulation unit 210 from the input region 2105 can pass through the first total reflection substrate layer 211 to vertically incident into the first modulation grating 2131 . When the first and second modulation gratings 2131 and 2132 are both in a diffraction state, first, the input monochromatic light 110 will be diffracted by the first modulation grating 2131 to be obliquely incident on the second total reflection substrate layer 212; then, after the input monochromatic light 110 is totally reflected by the second total reflection substrate layer 212 to penetrate the light-transmitting partition 2133, it is totally reflected by the first total reflection substrate layer 211 to be obliquely incident on the second modulation grating 2132; finally, after the input monochromatic light 110 is diffracted by the second modulation grating 2132 to be vertically incident on the second total reflection substrate layer 212, it is vertically output from the second output area 2104 of the optical modulation unit 210, so that the input monochromatic light 110 propagates along the total reflection optical path 2102 in the optical modulation unit 210. When the first modulation grating 2131 is in a transmission state, the input monochromatic light 110 will be transmitted through the first modulation grating 2131 to vertically enter the second reflective substrate layer 212, and then be vertically output from the first output area 2103 of the optical modulation unit 210, so that the input monochromatic light 110 propagates within the optical modulation unit 210 along the through optical path 2101.

[0146] It is worth noting that although the above example uses the example that the input monochromatic light 110 only undergoes two total reflections when propagating along the total reflection optical path 2102 to illustrate the advantages and features of the present invention, it does not constitute a limitation on the scope of protection of the present invention. In other examples of the present invention, the input monochromatic light 110 may also undergo more than two even number of total reflections when propagating along the total reflection optical path 2102. That is to say, the input monochromatic light 110 can pass through the light-transmitting spacer 2133 more than one odd number of times under the action of total reflection of the first and second total reflection substrate layers 211 and 212, and it only needs to adjust the length of the light-transmitting spacer 2133 (the spacing distance between the first and second modulation gratings 2131 and 2132) accordingly.

[0147] According to the above first embodiment of the present invention, illustratively, Figure 4 and Figure 5 As shown, the at least one light modulation unit 210 of the light modulation component 21 of the light conversion device 20 may include first, second and third light modulation units 210a, 210b, 210c, wherein the first, second and third light modulation units 210a, 210b, 210c are stacked together accordingly in sequence, so that the first output area 2103 and the second output area 2104 in the first, second and third light modulation units 210a, 210b, 210c are respectively aligned with each other. At the same time, the first quantum dot layer 22 is correspondingly arranged in the second output area 2104 of the first light modulation unit 210a, so that the input monochromatic light 110 emitted vertically from the second output area 2104 of the first light modulation unit 210a can be converted by the first quantum dot layer 22 into the first output monochromatic light 121; the second quantum dot layer 23 is correspondingly arranged in the second output area 2104 of the second light modulation unit 210b, so that the input monochromatic light 110 emitted vertically from the second output area 2104 of the second light modulation unit 210b can be converted by the second quantum dot layer 23 into the second output monochromatic light 122.

[0148] Thus, when the light conversion device 20 needs to provide the first output monochromatic light 121 for the scanning unit 30, that is, when the light modulation component 21 of the light conversion device 20 is controlled to conduct the first light path 201 and disconnect the second and third light paths 202 and 203, the light modulation component 21 of the light conversion device 20 is controlled to make the first light modulation unit 210 in the second state, and the second and third light modulation units 210b and 210c in the first state. At this time, Figure 4 and Figure 5As shown, the input monochromatic light 110 vertically incident from the input area 2105 of the first light modulator unit 210a will propagate along the total reflection optical path 2102 of the first light modulator unit 210a to be vertically emitted from the second output area 2104 of the first light modulator unit 210a, and after being converted into the first output monochromatic light 121 by the first quantum dot layer 22, it will pass through the second and third light modulator units 210b and 210c in sequence to be vertically emitted from the second output area 2104 of the third light modulator unit 210c.

[0149] Similarly, when the light conversion device 20 needs to provide the second output monochromatic light 122 for the scanning unit 30, that is, when the light modulation component 21 of the light conversion device 20 is controlled to conduct the second light path 202 and disconnect the first and third light paths 201, 203, the light modulation component 21 of the light conversion device 20 is controlled to make the second light modulation unit 210b in the second state, and the first and third light modulation units 210a, 210c in the first state. At this time, Figure 4 and Figure 5 As shown, the input monochromatic light 110 vertically incident from the input area 2105 of the first light modulator 210a will propagate along the through optical path 2101 of the first light modulator 210a to be vertically emitted from the first output area 2103 of the first light modulator 210a, and after vertically incident into the second light modulator 210b from the input area 2105 of the second light modulator 210b, propagate along the total reflection optical path 2102 of the second light modulator 210b to be vertically emitted from the second output area 2104 of the second light modulator 210b, and then, after being converted into the second output monochromatic light 122 via the second quantum dot layer 23, pass through the third light modulator 210c to be vertically emitted from the second output area 2104 of the third light modulator 210c.

[0150] In addition, when the light conversion device 20 needs to provide the third output monochromatic light 123 for the scanning unit 30, that is, when the light modulation component 21 of the light conversion device 20 is controlled to conduct the third light path 203 and disconnect the first and second light paths 201 and 202, the light modulation component 21 of the light conversion device 20 is controlled to make the third light modulation unit 210c in the second state, and the first and second light modulation units 210a and 210b in the first state. At this time, Figure 4 and Figure 5As shown, the input monochromatic light 110 vertically incident from the input area 2105 of the first light modulator 210a will propagate along the through-light path 2101 of the first light modulator 210a to be vertically emitted from the first output area 2103 of the first light modulator 210a, and after vertically incident from the input area 2105 of the second light modulator 210b to the second light modulator 210b, it will propagate along the through-light path 2101 of the second light modulator 210b to be vertically emitted from the first output area 2103 of the second light modulator 210b, and then after vertically incident from the input area 2105 of the third light modulator 210c to the third light modulator 210c, it will propagate along the total reflection light path 2012 of the third light modulator 210c to be vertically emitted from the second output area 2104 of the third light modulator 210c to directly serve as the third output monochromatic light 123.

[0151] It is worth noting that in the above first embodiment of the present invention, Figure 4 and Figure 5 As shown, the first optical path 201, the second optical path 202 and the third optical path 203 of the optical modulation component 21 correspond to the total reflection optical path 2102 of the first optical modulation unit 210a, the total reflection optical path 2102 of the second optical modulation unit 210b and the total reflection optical path 2102 of the third optical modulation unit 210c, respectively. In other words, the total reflection optical path 2102 of the first optical modulation unit 210a defines the first optical path 201 of the optical modulation component 21; the through optical path 2101 of the first optical modulation unit 210a and the total reflection optical path 2102 of the second optical modulation unit 210b jointly define the second optical path 202 of the optical modulation component 21; the through optical path 2101 of the first optical modulation unit 210a, the through optical path 2102 of the second optical modulation unit 210b 01 and the total reflection optical path 2102 of the third optical modulation unit 210c jointly define the third optical path 203 of the optical modulation component 21, so that the first, second and third output monochromatic lights 121, 122, 123 can be emitted from the second output area 2104 of the third optical modulation unit 210c in a time-sharing manner, so as to ensure that the optical conversion device 20 can provide the scanning unit 30 with the first, second and third output monochromatic lights 121, 122, 123 in a time-sharing manner.

[0152] It is worth mentioning that according to the above first embodiment of the present invention, Figure 2As shown, the micro-projection system 1 further includes a driving control unit 50, wherein the driving control unit 50 is communicatively connected to the monochromatic light source 10, and is used to control and drive the monochromatic light source 10 to emit the input monochromatic light 110; wherein the driving control unit 50 is communicatively connected to the light conversion device 20, and is used to control and drive the light conversion device 20 to convert the input monochromatic light 110 from the monochromatic light source 10 into the output monochromatic light 120 of the corresponding color; wherein the driving control unit 50 is communicatively connected to the scanning unit 30, and is used to control and drive the scanning unit 30 to scan the output monochromatic light 120 from the light conversion device 20 into the desired color image light.

[0153] Specifically, the driving control unit 50 is used to control the conversion state of the light conversion device 20 to convert the input monochromatic light 110 into the output monochromatic light 120 with the desired color in a time-sharing manner. For example, the driving control unit 50 is used to control the states (i.e., the transmission state and the diffraction state) of the first and second modulation gratings 2131 and 2132 in the modulation grating layer 213 of the light modulation component 21 of the light conversion device 20, so that the light modulation unit 210 in the light modulation component 21 is in the desired state (i.e., the first state and the second state), so as to conduct the first optical path 201, the second optical path 202, and the third optical path 203 in the light modulation component 21 in a time-sharing manner, and then control the light conversion device 20 through the driving control unit 50 to provide the first, second, and third output monochromatic lights 121, 122, 123 in a time-sharing manner. It is understandable that the driving control unit 50 can adjust the states of the first and second modulation gratings 2131 , 2132 by, but is not limited to, regulating the voltage values ​​applied to the first and second modulation gratings 2131 , 2132 .

[0154] Furthermore, the driving control unit 50 is further used to adjust the emission intensity of the monochromatic light source 10 to emit the input unit light 110 with the required light intensity, so that the first, second and third output monochromatic lights 121, 122, 123 provided in time-sharing manner via the light conversion device 20 have the required light intensity to meet the projection requirements of the micro-projection system 1. In addition, the driving control unit 50 is also used to adjust the scanning angle of the scanning unit 30 to scan the output monochromatic light 120 from the light conversion device 20 into the required color image light.

[0155] Attached Figure 8FIG. 2 shows a first variant implementation of the light conversion device 20 according to the first embodiment of the present invention. Compared with the first embodiment of the present invention, the light conversion device 20 according to the first variant implementation of the present invention is different in that: Figure 8 As shown, the second quantum dot layer 23 is correspondingly arranged in the first output area 2103 of the second light modulation unit 210b, so that the input monochromatic light 110 emitted vertically from the first output area 2103 of the second light modulation unit 210b can be converted into the second output monochromatic light 122 by the second quantum dot layer 23.

[0156] Thus, when the light conversion device 20 needs to provide the first output monochromatic light 121 for the scanning unit 30, the light modulation component 21 of the light conversion device 20 is controlled to make the first light modulation unit 210 in the second state, and the second and third light modulation units 210b and 210c in the first state. Figure 8 As shown, the input monochromatic light 110 vertically incident from the input area 2105 of the first light modulator unit 210a will propagate along the total reflection optical path 2102 of the first light modulator unit 210a to be vertically emitted from the second output area 2104 of the first light modulator unit 210a, and after being converted into the first output monochromatic light 121 by the first quantum dot layer 22, it will pass through the second and third light modulator units 210b and 210c in sequence to be vertically emitted from the second output area 2104 of the third light modulator unit 210c.

[0157] Similarly, when the light conversion device 20 needs to provide the second output monochromatic light 122 for the scanning unit 30, the light modulation component 21 of the light conversion device 20 is controlled to make the third light modulation unit 210c in the second state, and the first and second light modulation units 210a and 210b in the first state. Figure 8As shown in the figure, the input monochromatic light 110 vertically incident from the input area 2105 of the first light modulation unit 210a propagates along the through optical path 2101 of the first light modulation unit 210a to be vertically emitted from the first output area 2103 of the first light modulation unit 210a, and after vertically incident from the input area 2105 of the second light modulation unit 210b into the second light modulation unit 210b, it propagates along the through optical path 2101 of the first light modulation unit 210a to be vertically emitted from the first output area 2103 of the first light modulation unit 210a. 01 propagates to be vertically emitted from the first output area 2103 of the second light modulation unit 210b, and then after being converted into the second output monochromatic light 122 through the second quantum dot layer 23, it is vertically injected into the third light modulation unit 210c from the input area 2105 of the third light modulation unit 210c to propagate along the total reflection optical path 2102 of the third light modulation unit 210c, and finally vertically emitted from the second output area 2104 of the third light modulation unit 210c.

[0158] In addition, when the light conversion device 20 needs to provide the third output monochromatic light 123 for the scanning unit 30, the light modulation component 21 of the light conversion device 20 is controlled so that the second light modulation unit 210b is in the second state, and the first and third light modulation units 210a and 210c are in the first state. Figure 8 As shown, the input monochromatic light 110 vertically incident from the input area 2105 of the first light modulator 210a will propagate along the through optical path 2101 of the first light modulator 210a to be vertically emitted from the first output area 2103 of the first light modulator 210a, and after vertically incident into the second light modulator 210b from the input area 2105 of the second light modulator 210b, it will propagate along the total reflection optical path 2102 of the second light modulator 210b to be vertically emitted from the second output area 2104 of the second light modulator 210b, and then pass through the third light modulator 210c to be vertically emitted from the second output area 2104 of the third light modulator 210c to directly serve as the third output monochromatic light 123.

[0159] It is worth noting that in the above first variant embodiment of the present invention, Figure 8As shown, the first optical path 201, the second optical path 202 and the third optical path 203 of the optical modulation component 21 correspond to the total reflection optical path 2102 of the first optical modulation unit 210a, the total reflection optical path 2102 of the third optical modulation unit 210c and the total reflection optical path 2102 of the second optical modulation unit 210b respectively. In other words, the total reflection optical path 2102 of the first optical modulation unit 210a defines the first optical path 201 of the optical modulation component 21; the through optical path 2101 of the first optical modulation unit 210a and the total reflection optical path 2102 of the second optical modulation unit 210b jointly define the third optical path 203 of the optical modulation component 21; the through optical path 2101 of the first optical modulation unit 210a, the through optical path 2102 of the second optical modulation unit 210b 1 and the total reflection optical path 2102 of the third optical modulation unit 210c jointly define the second optical path 202 of the optical modulation component 21, so that the first, second and third output monochromatic lights 121, 122, 123 can be emitted from the second output area 2104 of the third optical modulation unit 210c in a time-sharing manner, so as to ensure that the optical conversion device 20 can provide the scanning unit 30 with the first, second and third output monochromatic lights 121, 122, 123 in a time-sharing manner.

[0160] It can be understood that in other examples of the present invention, the second quantum dot layer 23 can also be directly set in the input area 2105 of the third light modulation unit 210c, which can also achieve the effect that the light conversion device 20 can provide the scanning unit 30 with the first, second and third output monochromatic lights 121, 122, 123 in a time-sharing manner.

[0161] Attached Fig. 9 FIG. 2 shows a second variant embodiment of the light conversion device 20 according to the first embodiment of the present invention. Compared with the first embodiment of the present invention, the light conversion device 20 according to the second variant embodiment of the present invention is different in that: Fig. 9 As shown, the first quantum dot layer 22 is correspondingly arranged in the first output area 2103 of the first light modulation unit 210a, so that the input monochromatic light 110 emitted vertically from the first output area 2103 of the first light modulation unit 210a can be converted into the first output monochromatic light 121 by the first quantum dot layer 22.

[0162] Thus, when the light conversion device 20 needs to provide the first output monochromatic light 121 for the scanning unit 30, the light modulation component 21 of the light conversion device 20 is controlled to make the second light modulation unit 210b in the second state, and the first and third light modulation units 210a, 210c in the first state. Fig. 9 As shown, the input monochromatic light 110 vertically incident from the input area 2105 of the first light modulator unit 210a will propagate along the through-light path 2101 of the first light modulator unit 210a to be vertically emitted from the first output area 2103 of the first light modulator unit 210a, and after being converted into the first output monochromatic light 121 by the first quantum dot layer 22, it will propagate along the total reflection light path 2102 of the second light modulator unit 210b to be emitted from the second output area 2104 of the second light modulator unit 210b, and finally pass through the third light modulator unit 210c to be vertically emitted from the second output area 2104 of the third light modulator unit 210c.

[0163] Similarly, when the light conversion device 20 needs to provide the second output monochromatic light 122 for the scanning unit 30, the light modulation component 21 of the light conversion device 20 is controlled to make the first light modulation unit 210 in the second state, and the second and third light modulation units 210b and 210c in the first state. Fig. 9 As shown, the input monochromatic light 110 vertically incident from the input area 2105 of the first light modulator unit 210a will propagate along the total reflection optical path 2102 of the first light modulator unit 210a to be vertically emitted from the second output area 2104 of the first light modulator unit 210a, and after passing through the second light modulator unit 210b to be emitted from the second output area 2104 of the second light modulator unit 210b, it will be converted into the second output monochromatic light 122 through the second quantum dot layer 23 to pass through the third light modulator unit 210c and be vertically emitted from the second output area 2104 of the third light modulator unit 210c.

[0164] In addition, when the light conversion device 20 needs to provide the third output monochromatic light 123 for the scanning unit 30, the light modulation component 21 of the light conversion device 20 is controlled to make the first, second and third light modulation units 210a, 210b, 210c in the second state. Fig. 9As shown, the input monochromatic light 110 vertically incident from the input area 2105 of the first light modulator unit 210a will propagate along the total reflection optical path 2102 of the first, second and third light modulator units 210a, 210b, 210c in sequence to be vertically emitted from the second output area 2104 of the third light modulator unit 210c to directly serve as the third output monochromatic light 123.

[0165] It is worth noting that in the above second variant embodiment of the present invention, Fig. 9 As shown, the through optical path 2101 of the first optical modulation unit 210a and the total reflection optical path 2102 of the second optical modulation unit 210b jointly define the first optical path 201 of the optical modulation component 21; the total reflection optical path 2102 of the first optical modulation unit 210a defines the second optical path 202 of the optical modulation component 21; the total reflection optical paths 2102 of the first, second and third optical modulation units 210a, 210b, 210c jointly define the third optical path 203 of the optical modulation component 21, so that the first, second and third output monochromatic lights 121, 122, 123 can be emitted from the second output area 2104 of the third optical modulation unit 210c in a time-sharing manner, so as to ensure that the optical conversion device 20 can provide the first, second and third output monochromatic lights 121, 122, 123 to the scanning unit 30 in a time-sharing manner.

[0166] It is worth mentioning that in other examples of the present invention, the first and second quantum dot layers 22, 23 of the light conversion device 20 can also be correspondingly arranged in the first output area 2103 of the first and second light modulation units 210a, 210b. At this time, the present invention only needs to adjust the states of the first, second and third light modulation units 210a, 210b, 210c in the light modulation component 21 accordingly, and can still ensure that the light conversion device 20 can provide the first, second and third output monochromatic lights 121, 122, 123 to the scanning unit 30 in a time-sharing manner, and the present invention will not repeat this.

[0167] Attached Fig.10The third variant implementation of the light conversion device 20 according to the first embodiment of the present invention is shown. Compared with the first embodiment of the present invention, the light conversion device 20 according to the third variant implementation of the present invention is different in that: the light conversion device 20 further includes a coupling element 214, wherein the coupling element 214 is arranged in the input area 2105 of the first light modulation unit 210a of the light modulation component 21, and the coupling element 214 is used to couple the input monochromatic light 110 into the first light modulation unit 210.

[0168] For example, in this variant embodiment of the present invention, Fig.10 As shown, the coupling element 214 is used to obliquely couple the vertically incident input monochromatic light 110 into the first light modulation unit 210, so that the input monochromatic light 110 is obliquely incident into the first modulation grating 2131 of the first light modulation unit 210a. Of course, in other examples of the present invention, the coupling element 214 can also be used to vertically couple the obliquely incident input monochromatic light 110 into the first light modulation unit 210, so that the input monochromatic light 110 is vertically incident into the first light modulation unit 210a.

[0169] It is worth noting that since the input monochromatic light 110 is incident on the first modulation grating 2131 of the first light modulation unit 210a at an angle, when the first modulation grating 2131 in the first light modulation unit 210 is in a transmission state and the second modulation grating 2132 is in a diffraction state, the first light modulation unit 210 is in the second state, that is, the total reflection light path 2102 of the first light modulation unit 210a is turned on, and the through light path 2101 of the first light modulation unit 210a is disconnected; and when the first modulation grating 2131 in the first light modulation unit 210 is in a diffraction state and the second modulation grating 2132 is in a transmission state, the first light modulation unit 210 is in the first state, that is, the total reflection light path 2102 of the first light modulation unit 210a is disconnected, and the through light path 2101 of the first light modulation unit 210a is turned on.

[0170] Preferably, the coupling element 214 can be implemented as a diffraction optical element, used to couple the input monochromatic light 110 into the first total reflection substrate layer 211 of the first light modulation unit 210a along a predetermined inclination angle, and then obliquely incident into the first modulation grating 2131 along the predetermined inclination angle, wherein the predetermined inclination angle is greater than or equal to the total reflection angle of the interface between the first or second total reflection substrate layer 211 / 212 and the air, so that the input monochromatic light 110 can be totally internally reflected by the first and second total reflection substrate layers 211, 212 after being transmitted through the first modulation grating 2131.

[0171] Of course, in other examples of the present invention, the coupling element 214 can also be implemented as other types of optical elements such as a prism element or a lens, as long as it can ensure that the input monochromatic light 110 is coupled into the first total reflection substrate layer 211 of the first light modulation unit 210a along the predetermined tilt angle.

[0172] It is worth noting that in the micro-projection system 1 of the first embodiment of the present invention, Figure 2 and Figure 4 As shown, since the input monochromatic light 110 is vertically input into the light conversion device 20 from the input area 2105 of the first light modulation unit 210a of the light modulation component 21, and the first, second and third output monochromatic lights 121, 122, 123 are vertically output from the light conversion device 20 from the second output area 2104 of the third light modulation unit 210c of the light modulation component 21, so that the propagation direction of the input unit light 110 is consistent with the propagation direction of the first, second and third output monochromatic lights 121, 122, 123, that is, the light input position and the light output position of the light conversion device 20 are respectively located on opposite sides of the light conversion device 20, so the monochromatic light source 10 and the scanning unit 30 in the micro-projection system 1 are respectively located on opposite sides of the light conversion device 20, resulting in a larger volume of the micro-projection system 1. Therefore, in order to reasonably utilize space and reduce the volume of the micro-projection system, a second embodiment of the present invention further provides a micro-projection system, which can dispose the monochromatic light source 10 and the scanning unit 30 on the same side of the light conversion device.

[0173] Specifically, refer to the accompanying drawings of the specification. Figures 11 to 13 , a micro-projection system 1A according to a second embodiment of the present invention is explained. Compared with the above-mentioned first embodiment of the present invention, the micro-projection system 1A according to the second embodiment of the present invention is different in that: Fig.11 and Fig.12As shown, the light input position and the light output position of the light conversion device 20A of the micro-projection system 1A are located on the same side of the light conversion device 20A, so that the monochromatic light source 10 and the scanning unit 30 are arranged on the same side of the light conversion device 20A, which helps to reduce the volume of the micro-projection system 1A.

[0174] More specifically, if Fig.12 and Fig.13 As shown, the first output region 2103A and the second output region 2014A of the light modulation unit 210A of the light modulation component 21A of the light conversion device 20A are respectively located on the first total reflection substrate layer 211 and the second total reflection substrate layer 212 of the light modulation unit 210A, and the input region 2105A of the light modulation unit 210A is located on the second total reflection substrate layer 212 of the light modulation unit 210A. In other words, the second output region 2014A and the input region 2105A are distributed side by side on the second total reflection substrate layer 212 of the light modulation unit 210A, and the first output region 2103A is correspondingly arranged on the first total reflection substrate layer 211 of the light modulation unit 210A, so that the first output region 2103A corresponds to the input region 2105A.

[0175] At the same time, Fig.13 As shown, the first modulation grating 2131 and the second modulation grating 2132 in the modulation grating layer 213A of the optical modulation unit 210A are arranged side by side between the first total reflection substrate layer 211 and the second total reflection substrate layer 212, so that the first total reflection substrate layer 211, the modulation grating layer 213 and the second total reflection substrate layer 212 are stacked together in sequence.

[0176] In this way, when the first modulation grating 2131 and the second modulation grating 2132 in the modulation grating layer 213A of the optical modulation unit 210A are both in the diffraction state, the input monochromatic light 110 vertically incident from the input area 2105A on the second total reflection substrate layer 212 is first incident obliquely into the first total reflection substrate layer 211 for total reflection after diffraction by the first modulation grating 2131, and then incident obliquely into the second modulation grating 2132 for diffraction, and finally vertically emitted from the second output area 2104A on the second total reflection substrate layer 212, so that the optical modulation unit 210A is in the second state, that is, the total reflection optical path 2102A of the optical modulation unit 210A is turned on, and the through optical path 2101A of the optical modulation unit 210A is disconnected.

[0177] Similarly, when the first modulation grating 2131 and the second modulation grating 2132 in the modulation grating layer 213A of the optical modulation unit 210A are both in the transmission state, the input monochromatic light 110 vertically incident from the input area 2105A on the second total reflection substrate layer 211A, after being transmitted through the first modulation grating 2131, first vertically enters the first total reflection substrate layer 211 to be vertically emitted from the first output area 2103A on the first total reflection substrate layer 211, so that the optical modulation unit 210A is in the first state, that is, the through optical path 2101A of the optical modulation unit 210A is turned on, and the total reflection optical path 2102A of the optical modulation unit 210A is disconnected.

[0178] It is worth noting that Fig.13 As shown, the through optical path 2101A of the optical modulation unit 210A starts from the input area 2105A, and after passing through the second total reflection substrate layer 212, the first modulation grating 2131 and the first total reflection substrate layer 211 in sequence, it ends at the first output area 2103A; the total reflection optical path 2102A of the optical modulation unit 210A starts from the input area 2105A, first passes through the second total reflection substrate layer 212 and the first modulation grating 2131 in sequence in a forward direction, and after turning by total reflection in the first total reflection substrate layer 211 to extend to the second modulation grating 2132, it passes through the second modulation grating 2132 and the second total reflection substrate layer 212 in the reverse direction to end at the second output area 2104A.

[0179] In the above second embodiment of the present invention, preferably, as Fig.12 and Fig.13As shown, the first modulation grating 2131 and the second modulation grating 2132 in the modulation grating layer 213A of the optical modulation unit 210A are closely arranged between the first total reflection substrate layer 211 and the second total reflection substrate layer 212, so that there is no gap between the first modulation grating 2131 and the second modulation grating 2132, so that the total reflection optical path 2102A of the optical modulation unit 210A is turned by total reflection only once in the first total reflection substrate layer 211, and then extends to the second modulation grating 2132. In other words, there is no need to set any light-transmitting partition between the first modulation grating 2131 and the second modulation grating 2132 in the modulation grating layer 213A, so that the input monochromatic light 2102A propagating along the total reflection optical path 2102A is totally reflected only once in the first total reflection substrate layer 211 before propagating to the second modulation grating 2132, so as to ensure that the light modulation unit 210A is in the second state, which helps to reduce the lateral size of the light modulation unit 210A, and further reduce the volume and weight of the light conversion device 20A.

[0180] It is worth noting that in the first variation example of the light modulation unit 210A of the second embodiment of the present invention, Fig.14A As shown, the first modulation grating 2131 and the second modulation grating 2132 in the modulation grating layer 213A of the optical modulation unit 210A can also be arranged at intervals between the first total reflection substrate layer 211 and the second total reflection substrate layer 212 to form an air gap 2130A between the first modulation grating 2131 and the second modulation grating 2132, so that the total reflection optical path 2102A of the optical modulation unit 210A is turned after an odd number of total reflections in the first total reflection substrate layer 211 before extending to the second modulation grating 2131A. It can be understood that in this variant example of the present invention, the interface between the first total reflection substrate layer 211 and the air gap 2130A can also be totally reflected, so that the input monochromatic light 110 propagating along the total reflection optical path 2102A can be totally reflected in the first total reflection substrate layer 211 for an odd number of times before propagating to the second modulation grating 2132, and the optical modulation unit 210A is still ensured to be in the second state. In other words, the first total reflection substrate layer 211 is implemented as a waveguide, so that the input monochromatic light 110 can undergo multiple total reflections in the first total reflection substrate layer 211 to propagate from the first modulation grating 2131 to the second modulation grating 2132 .

[0181] Of course, in the second variation example of the light modulation unit 210A of the second embodiment of the present invention, Fig. 14BAs shown, the modulation grating layer 213A of the light modulation unit 210A may further include the light-transmitting spacer 2133A, wherein the light-transmitting spacer 2133A is disposed between the first modulation grating 2131 and the second modulation grating 2132, so that the first modulation grating 2131 and the second modulation grating 2132 are arranged at intervals between the first total reflection substrate layer 211 and the second total reflection substrate layer 212. At the same time, the total reflection optical path 2102A of the light modulation unit 210A can pass through the light-transmitting spacer 2133A, so that the input monochromatic light 110 propagating along the total reflection optical path 2102A can be totally reflected in the first total reflection substrate layer 211 and the second total reflection substrate layer 212 before and after passing through the light-transmitting spacer 2133A.

[0182] For example, in the above second variation example of the present invention, Fig. 14B As shown, the input monochromatic light 110 vertically incident on the optical modulation unit 210A from the input region 2105A can penetrate the second total reflection substrate layer 212 to vertically incident on the first modulation grating 2131. When the first and second modulation gratings 2131 and 2132 are both in a diffraction state, firstly, the input monochromatic light 110 will be diffracted by the first modulation grating 2131 to obliquely incident on the first total reflection substrate layer 211; secondly, after the input monochromatic light 110 is totally reflected by the first total reflection substrate layer 211 to penetrate the light-transmitting spacer 2133A, it is totally reflected by the second total reflection substrate layer 212 to penetrate the light-transmitting spacer 2133A for the second time; then, the input monochromatic light 110 is diffracted by the first total reflection substrate layer 211 to penetrate the light-transmitting spacer 2133A; The monochromatic light 110 is then totally reflected for the second time by the first total reflection substrate layer 211 and is incident obliquely onto the second modulation grating 2132. Finally, after being diffracted by the second modulation grating 2132 and incident vertically onto the second total reflection substrate layer 212, the input monochromatic light 110 is vertically output from the second output region 2104A of the optical modulation unit 210A, so that the input monochromatic light 110 propagates within the optical modulation unit 210A along the total reflection optical path 2102A.

[0183] It is worth noting that although the above-mentioned second variation example uses the example that the input monochromatic light 110 only undergoes three total reflections when propagating along the total reflection optical path 2102A to illustrate the advantages and characteristics of the present invention, it does not constitute a limitation on the scope of protection of the present invention. In other examples of the present invention, the input monochromatic light 110 may also undergo more than three odd total reflections when propagating along the total reflection optical path 2102A. That is to say, the input monochromatic light 110 can penetrate the light-transmitting spacer 2133A more than two even times under the action of total reflection of the first and second total reflection substrate layers 211 and 212, and it only needs to adjust the length of the light-transmitting spacer 2133A accordingly (the spacing distance between the first and second modulation gratings 2131 and 2132).

[0184] According to the above second embodiment of the present invention, illustratively, Fig.12 and 13 As shown, the light modulation component 21A of the light conversion device 20A may include first, second and third light modulation units 210Aa, 210Ab, 210Ac, wherein the first, second and third light modulation units 210Aa, 210Ab, 210Ac are stacked together accordingly in sequence, so that the first output area 2103A and the second output area 2104A in the first, second and third light modulation units 210Aa, 210Ab, 210Ac are respectively aligned with each other, that is, the first modulation grating 2131 and the second modulation grating 2132 in the first, second and third light modulation units 210Aa, 210Ab, 210Ac are respectively aligned with each other. At the same time, the first quantum dot layer 22 is correspondingly arranged in the second output area 2104AA of the first light modulation unit 210Aa, so that the input monochromatic light 110 emitted vertically from the second output area 2104A of the first light modulation unit 210Aa can be converted by the first quantum dot layer 22 into the first output monochromatic light 121; the second quantum dot layer 23 is correspondingly arranged in the second output area 2104A of the second light modulation unit 210Ab, so that the input monochromatic light 110 emitted vertically from the second output area 2104A of the second light modulation unit 210Ab can be converted by the second quantum dot layer 23 into the second output monochromatic light 122.

[0185] Thus, when the optical conversion device 20A needs to provide the first output monochromatic light 121 for the scanning unit 30, that is, when the optical modulation component 21A of the optical conversion device 20A is controlled to conduct the first optical path 201A and disconnect the second and third optical paths 202A, 203A, the optical modulation component 21A of the optical conversion device 20A is controlled to make the first optical modulation unit 210Aa in the second state, and the second and third optical modulation units 210Ab, 210Ac in the first state. At this time, Fig.12 As shown, the input monochromatic light 110 vertically incident from the input area 2105A of the third light modulator unit 210Ac will propagate along the projection optical path 2101A of the third and second light modulator units 210Ac and 210Ab in sequence to be vertically emitted from the first output area 2104A of the second light modulator unit 210Ab, and after propagating along the total reflection optical path 2102A of the first light modulator unit 210Aa to be vertically emitted from the second output area 2104A of the first light modulator unit 210Aa, it will be converted into the first output monochromatic light 121 through the first quantum dot layer 22, and finally pass through the second and third light modulator units 210Ab and 210Ac in sequence to be vertically emitted from the second output area 2104A of the third light modulator unit 210Ac.

[0186] Similarly, when the light conversion device 20A needs to provide the second output monochromatic light 122 for the scanning unit 30, that is, when the light modulation component 21A of the light conversion device 20A is controlled to conduct the second light path 202A and disconnect the first and third light paths 201A and 203A, the light modulation component 21A of the light conversion device 20A is controlled to make the second light modulation unit 210Ab in the second state, and the third light modulation unit 210Ac in the first state. At this time, Fig.12As shown, the input monochromatic light 110 vertically incident from the input area 2105A of the third light modulator 210Ac will propagate along the through optical path 2101A of the third light modulator 210Ac to be vertically emitted from the first output area 2103A of the third light modulator 210Ac, and after vertically incident into the second light modulator 210Ab from the input area 2105A of the second light modulator 210Ab, will propagate along the total reflection optical path 2102A of the second light modulator 210Ab to be vertically emitted from the second output area 2104A of the second light modulator 210Ab, and then, after being converted into the second output monochromatic light 122 via the second quantum dot layer 23, will pass through the third light modulator 210Ac to be vertically emitted from the second output area 2104A of the third light modulator 210Ac.

[0187] In addition, when the light conversion device 20A needs to provide the third output monochromatic light 123 for the scanning unit 30, that is, when the light modulation component 21A of the light conversion device 20A is controlled to conduct the third light path 203A and disconnect the first and second light paths 201A and 202A, the light modulation component 21A of the light conversion device 20A is controlled to make the third light modulation unit 210Ac in the second state. Fig.12 As shown, the input monochromatic light 110 vertically incident from the input area 2105A of the third light modulator unit 210Ac will propagate along the total reflection optical path 2102A of the third light modulator unit 210Ac to be vertically emitted from the second output area 2104A of the third light modulator unit 210Ac to directly serve as the third output monochromatic light 123.

[0188] It is worth noting that in the above first embodiment of the present invention, Fig.12 and Fig.13As shown, the first optical path 201A, the second optical path 202A and the third optical path 203A of the optical modulation component 21A correspond to the total reflection optical path 2102A of the first optical modulation unit 210Aa, the total reflection optical path 2102A of the second optical modulation unit 210Ab and the total reflection optical path 2102A of the third optical modulation unit 210Ac, respectively. In other words, the total reflection optical path 2102A of the third optical modulation unit 210Ac defines the third optical path 203A of the optical modulation component 21A; the through optical path 2101A of the third optical modulation unit 210Ac and the total reflection optical path 2102A of the second optical modulation unit 210Ab jointly define the second optical path 202A of the optical modulation component 21A; the through optical path 2101A of the third optical modulation unit 210Ac and the through optical path 2102A of the second optical modulation unit 210Ab jointly define the second optical path 202A of the optical modulation component 21A; the through optical path 2101A of the third optical modulation unit 210Ac and the through optical path 2102A of the second optical modulation unit 210Ab jointly define the second optical path 202A of the optical modulation component 21A. The first optical path 201A and the total reflection optical path 2102A of the first optical modulation unit 210Aa jointly define the first optical path 201A of the optical modulation component 21A, so that the first, second and third output monochromatic lights 121, 122, 123 can be emitted from the second output area 2104A of the third optical modulation unit 210Ac in a time-sharing manner, so as to ensure that the optical conversion device 20A can provide the scanning unit 30 with the first, second and third output monochromatic lights 121, 122, 123 in a time-sharing manner.

[0189] It is worth mentioning that in the above second embodiment of the present invention, when the light conversion device 20A provides the first, second and third output monochromatic lights 121, 122, 123 to the scanning unit 30 in a time-sharing manner, the first light modulation unit 210Aa in the light modulation component 21A of the light conversion device 20A can all be in the second state, that is, the first light modulation unit 210Aa in the light modulation component 21A only needs to provide the total reflection light path 2102A, and does not need to provide the through light path 2101A. Therefore, the first light modulation unit 210Aa in the light modulation component 21A can be replaced by a total reflection unit.

[0190] Attached Fig.15The first variant implementation of the light conversion device 20A according to the second embodiment of the present invention is shown. Compared with the second embodiment of the present invention, the difference of the light conversion device 20A according to this variant implementation of the present invention is that the light modulation component 21A of the light conversion device 20A further includes a total reflection unit 215A, so that the first light modulation unit 210Aa in the light modulation component 21A is replaced by the total reflection unit 215A, so that the light modulation component 21A only includes the second light modulation unit 210Ab and the third light modulation unit 210Ac. At the same time, the first quantum dot layer 22 is arranged between the total reflection unit 215A and the second light modulation unit 210Ab, and the total reflection unit 215A is used to totally reflect the input monochromatic light 110 emitted from the first output area 2103A of the second light modulation unit 210Ab back to the second light modulation unit 210Ab to pass through the first quantum dot layer 22, so that the input monochromatic light 110 passing through the first quantum dot layer 22 is converted into the first output monochromatic light 121, and then the first output monochromatic light 121 passes through the second light modulation unit 210Ab and the third light modulation unit 210Ac in turn to be emitted from the second output area 2104A of the third light modulation unit 210Ac, and it is also possible to provide the scanning unit 30 with the first output monochromatic light 121 through the light conversion device 20A.

[0191] For example, in this variant embodiment of the present invention, Fig.15 As shown, the total reflection unit 215A may include, but is not limited to, a waveguide element 2151A, a coupling element 2152A, and a coupling element 2153A, wherein the coupling element 2152A and the coupling element 2153A are arranged side by side on the same side of the waveguide element 2151A, and the coupling element 2152A and the coupling element 2153A correspond to the first output region 2103A and the second output region 2103A of the second optical modulation unit 210Ab, respectively. 04A, wherein the coupling-in element 2152A is used for obliquely coupling the input monochromatic light 110 vertically emitted from the first output area 2103A of the second optical modulation unit 210Ab into the waveguide element 2151A so that the input monochromatic light 110 is totally reflected in the waveguide element 2151A; and wherein the coupling-out element 2153A is used for vertically coupling the input monochromatic light 110 totally reflected by the waveguide element 2151A out of the waveguide element 2151A.

[0192] At the same time, Fig.15As shown, the first quantum dot layer 22 is correspondingly arranged on the outcoupling element 2153A, so that the first quantum dot layer 22 is located between the outcoupling element 2153A and the second light modulating unit 210Ab. In this way, when the input monochromatic light 110 is vertically coupled out of the waveguide element 2151A through the outcoupling element 2153A, the input monochromatic light 110 will pass through the first quantum dot layer 22 to be converted into the first output monochromatic light 121; then, the first output monochromatic light 121 will sequentially pass through the second light modulating unit 210Ab and the third light modulating unit 210Ac to be vertically emitted from the second output region 2104A of the third light modulating unit 210Ac.

[0193] Of course, in other examples of the present invention, the first quantum dot layer 22 can also be correspondingly arranged in the coupling element 2152A, or be simultaneously arranged in the coupling element 2152A and the coupling element 2153A, so that the input monochromatic light 110 vertically emitted from the first output area 2103A of the second light modulation unit 210Ab is first converted into the first output monochromatic light 121 by the first quantum dot layer 22, and then the first output monochromatic light 121 is coupled into the waveguide element 2151A via the coupling element 2152A, thereby ensuring that the light conversion device 20A provides the scanning unit 30 with the first output monochromatic light 121.

[0194] It is worth noting that the waveguide element 2151A of the total reflection unit 215A of the present invention can be, but is not limited to, implemented as the first or second total reflection substrate layer 211A / 212A, that is, the waveguide element 2151A can be, but is not limited to, made of a light-transmitting material such as glass. In addition, the coupling-in element 2152A and the coupling-out element 2153A of the total reflection unit 215A can be, but are not limited to, implemented as other types of optical elements such as diffractive optical elements, prism elements, or lenses, as long as it can ensure that the input monochromatic light 110 is coupled into or coupled out of the waveguide element 2151A.

[0195] Attached Fig.16 A second variant implementation of the light conversion device 20A according to the second embodiment of the present invention is shown. Compared with the first variant implementation of the second embodiment of the present invention, the light conversion device 20A according to this variant implementation of the present invention is different in that the total reflection unit 215A is implemented as a total reflection prism 2154A, wherein the inclined surface of the total reflection prism 2154A faces the second light modulation unit 210Ab, and the first quantum dot layer 22 is disposed between the inclined surface of the total reflection prism 2154A and the second light modulation unit 210Ab.

[0196] For example, Fig.16 As shown, the first quantum dot layer 22 is disposed on the inclined surface of the total reflection prism 2154A, and the first quantum dot layer 22 corresponds to the second output region 2104A of the second light modulation unit 210Ab. In this way, the input monochromatic light 110 emitted vertically from the first output area 2103A of the second light modulation unit 210Ab first enters the total reflection prism 2154A vertically from the inclined surface of the total reflection prism 2154A, and after being totally reflected by the two right-angled surfaces of the total reflection prism 2154A in sequence, it is then emitted vertically from the inclined surface of the total reflection prism 2154A to pass through the first quantum dot layer 22, so that the input monochromatic light 110 passing through the first quantum dot layer 22 is converted into the first output monochromatic light 121; then, the first output monochromatic light 121 passes through the second light modulation unit 210Ab and the third light modulation unit 210Ac in sequence to be emitted from the second output area 2104A of the third light modulation unit 210Ac, and the first output monochromatic light 121 can also be provided to the scanning unit 30 through the light conversion device 20A.

[0197] Of course, in other examples of the present invention, the first quantum dot layer 22 may also correspond to the first output area 2103A of the second light modulator unit 210Ab, or correspond to both the first output area 2103A and the second output area 2104A of the second light modulator unit 210Ab, so that the input monochromatic light 110 emitted vertically from the first output area 2103A of the second light modulator unit 210Ab is first converted into the first output monochromatic light 121 by the first quantum dot layer 22, and then vertically enters the total reflection prism 2154A from the inclined surface of the total reflection prism 2154A, thereby ensuring that the light conversion device 20A provides the scanning unit 30 with the first output monochromatic light 121.

[0198] Attached Fig.17A and Fig. 17B FIG. 2 shows a third variant embodiment of the light conversion device 20A according to the second embodiment of the present invention. Compared with the second embodiment of the present invention, the light conversion device 20B according to this variant embodiment of the present invention is different in that: Fig.17A and Fig. 17BAs shown, the optical modulation unit 210B of the optical modulation component 21B only includes the first total reflection substrate layer 211 and the modulation grating layer 213, but does not include the second total reflection substrate layer 212, wherein the second output area 2104B of the optical modulation unit 210B is located at the second modulation grating 2132 of the modulation grating layer 213A, so that the input monochromatic light 110 can be directly emitted from the second modulation grating 2132 of the modulation grating layer 213B; and the input area 2105B of the optical modulation unit 210B is located at the first modulation grating 2131 of the modulation grating layer 213B, so that the input monochromatic light 110 can be directly emitted from the first modulation grating 2131 of the modulation grating layer 213B to propagate along the through optical path 2101B or the total reflection optical path 2102B.

[0199] For example, Fig.17A As shown, the first quantum dot layer 22 can be but is not limited to being directly set on the second modulation grating 2132 of the first light modulation unit 210Ba, so that the input monochromatic light 110 emitted from the second modulation grating 2132 of the first light modulation unit 210Ba is directly converted by the first quantum dot layer 22 into the first output monochromatic light 121, and then the first output monochromatic light 121 passes through the second light modulation unit 210Bb and the third light modulation unit 210Bc in sequence to be emitted from the second modulation grating 2132 of the third light modulation unit 210Bc, and it is also possible to provide the first output monochromatic light 121 to the scanning unit 30 through the light conversion device 20B.

[0200] At the same time, the second quantum dot layer 23 can also be directly set on the second modulation grating 2132 of the second light modulation unit 210Bb, so that the input monochromatic light 110 emitted from the second modulation grating 2132 of the second light modulation unit 210Bb is directly converted by the second quantum dot layer 23 into the second output monochromatic light 122, and then the first output monochromatic light 121 passes through the third light modulation unit 210Bc to be emitted from the second modulation grating 2132 of the third light modulation unit 210Bc, and it is also possible to provide the scanning unit 30 with the second output monochromatic light 122 through the light conversion device 20B.

[0201] It can be understood that since the light modulation unit 210B of the light modulation component 21B does not include the second total reflection substrate layer 212, the volume and weight of the light modulation unit 210B are greatly reduced, which helps to further reduce the volume and weight of the light modulation component 21B, and further reduce the volume and weight of the light conversion device 20B.

[0202] It is worth noting that, although the light conversion devices in the first and second embodiments of the present invention provide the first, second and third output monochromatic lights 121, 122, 123 along the same optical path, the light-transmitting areas of the first and second modulation gratings 2131, 2132 in the light modulation unit of the light modulation component of the light conversion device only need to match the quantum dot layer, so that the size (i.e., the lateral size) of the light-transmitting areas of the first and second modulation gratings 2131, 2132 can be between a few microns and tens of microns, and the first and second modulation gratings 2131, 2132 can be between a few microns and tens of microns. The thickness (i.e., the longitudinal dimension) of the gratings 2131 and 2132 can also be in the micron range, so the overall structure of the light modulation unit can be made thin and compact, so as to obtain the light modulation unit with extremely small overall size, so that even if the light conversion device provides the first, second and third output monochromatic lights 121, 122, 123 along different optical paths, as long as the beam combining deviation caused by the spacing between the first, second and third output monochromatic lights 121, 122, 123 is within a controllable range, the light conversion device of the present invention can also meet the projection requirements of the micro-projection system.

[0203] Reference to the attached drawings of the specification Fig.18 and Fig.19 As shown in FIG. 1 , the micro-projection system 1C according to a third embodiment of the present invention is illustrated. Compared with the first embodiment of the present invention, the micro-projection system 1C according to the third embodiment of the present invention is different in that: Fig.18 As shown, the light conversion device 20C has three different output positions, which are used to provide the scanning unit 30 with the output monochromatic light 120 of different colors (such as the first, second and third output monochromatic light 121, 122, 123) along different optical paths, so that the scanning unit 30 can still scan the output monochromatic light 120 from different optical paths into a color image to achieve color projection of the micro-projection system 1C.

[0204] Specifically, Fig.19As shown, the light modulation component 21C of the light conversion device 20C includes only one light modulation unit 210C, wherein the light modulation unit 210C includes a first total reflection substrate layer 211, a second total reflection substrate layer 212 and a modulation grating layer 213C, and the modulation grating layer 213C is stacked between the first total reflection substrate layer 211 and the second total reflection substrate layer 212, wherein the modulation grating layer 213C includes a first modulation grating 2131C, a second modulation grating 2132C and a third modulation grating 2133C, and the first modulation grating 2131C, the second modulation grating 2132C and the third modulation grating 2133C are distributed side by side between the first total reflection substrate layer 211 and the second total reflection substrate layer 212. At the same time, the first and second quantum dot layers 22 and 23 of the light conversion device 20C are arranged side by side on the second total reflection substrate layer 212, and the first and second quantum dot layers 22 and 23 correspond to the first and second modulation grating layers 2131C and 2132C of the modulation grating layer 213C respectively.

[0205] It is worth noting that, since the light modulation component 21C of the light conversion device 20C includes only one light modulation unit 210C, the longitudinal size and weight of the light conversion device 20C are greatly reduced, which helps to greatly reduce the volume and weight of the micro-projection system 1C, in line with the current development trend of smaller volume and lighter weight. It is understandable that in other examples of the present invention, the light modulation unit 210C can also provide the first, second and third output monochromatic lights in a time-sharing manner without including the first total reflection substrate layer 211, so as to further reduce the longitudinal size and weight of the light conversion device 20C.

[0206] More specifically, if Fig.19As shown, the first optical path 201C of the optical conversion device 20C of the present invention sequentially passes through the first total reflection substrate layer 211, the first modulation grating 2131C, the second total reflection substrate layer 212 and the first quantum dot layer 22, so as to turn on or off the first optical path 201C by the state of passing through the first modulation grating 2131C, and convert the input monochromatic light 110 propagating along the first optical path 201C into the first output monochromatic light 121 through the first quantum dot layer 22; the second optical path 202C of the optical conversion device 20C sequentially passes through the first total reflection substrate layer 211, the second modulation grating 2132C, the second total reflection substrate layer 212 and the first quantum dot layer 22. The second quantum dot layer 23 turns on or off the second optical path 202C by the state of the second modulation grating 2132C, and converts the input monochromatic light 110 propagating along the second optical path 202C into the second output monochromatic light 122 through the second quantum dot layer 23; the third optical path 203C of the optical conversion device 20C sequentially passes through the first total reflection substrate layer 211, the third modulation grating 2133C and the second total reflection substrate layer 212, so as to turn on or off the third optical path 203C by the state of the third modulation grating 2133C, and directly uses the input monochromatic light 110 propagating along the third optical path 203C as the third output monochromatic light 123.

[0207] Thus, when the light conversion device 20C provides the first output monochromatic light 121 to the scanning unit 30, the first modulation grating 2131C is in a transmission state, and the second and third modulation gratings 2132C and 2133C are both in a diffraction state, so that the first light path 201C is turned on, and the second and third light paths 202C and 203C are turned off. Fig.19 As shown, the input monochromatic light 110 will propagate along the first optical path 201C to sequentially pass through the first total reflection substrate layer 211, the first modulation grating 2131C, the second total reflection substrate layer 212 and the first quantum dot layer 22, and will be converted into the first output monochromatic light 121 when passing through the first quantum dot layer 22.

[0208] Similarly, when the light conversion device 20C provides the second output monochromatic light 122 to the scanning unit 30, the second modulation grating 2132C is in a transmission state, and the first and third modulation gratings 2131C and 2133C are both in a diffraction state, so that the second light path 202C is turned on, and the first and third light paths 201C and 203C are turned off. Fig.19As shown, the input monochromatic light 110 will propagate along the second optical path 202C to sequentially pass through the first total reflection substrate layer 211, the second modulation grating 2132C, the second total reflection substrate layer 212 and the second quantum dot layer 23, and will be converted into the second output monochromatic light 122 when passing through the second quantum dot layer 23.

[0209] In addition, when the light conversion device 20C provides the third output monochromatic light 123 to the scanning unit 30, the third modulation grating 2133C is in a transmission state, and the first and second modulation gratings 2131C and 2132C are both in a diffraction state, so that the third light path 203C is turned on, and the first and second light paths 201C and 202C are turned off. Fig.19 As shown, the input monochromatic light 110 will propagate along the third optical path 203C to sequentially pass through the first total reflection substrate layer 211, the third modulation grating 2133C and the second total reflection substrate layer 212 to directly use the input monochromatic light 110 as the third output monochromatic light 123.

[0210] Preferably, if Fig.19 As shown, the first optical path 201C, the second optical path 202C and the third optical path 203C of the light conversion device 20C are parallel to each other, so as to ensure that the first, second and third output monochromatic lights 121, 122, 123 are provided in the same direction at different times, and also help to reduce the spacing between the first, second and third output monochromatic lights 121, 122, 123, thereby reducing the beam combining deviation of the light conversion device 20C and meeting the projection requirements of the micro-projection system 1C.

[0211] It is worth noting that in the above-mentioned first embodiment of the present invention, it is only necessary to adjust the states of the first, second and third light modulation units 210a, 210b, 210c accordingly, so that the first, second and third output monochromatic lights 121, 122, 123 can also be emitted from the first output area 2103 and the second output area 2104 of the third light modulation unit 210c of the light modulation component 21, respectively, so as to provide monochromatic lights of different colors along two optical paths, which helps to further reduce the beam combining deviation of the light conversion device and is beneficial to meeting the projection requirements of the micro-projection system.

[0212] In the third embodiment of the present invention, the monochromatic light source 10C of the micro-projection system 1C needs to correspond to the first modulation grating 2131C, the second modulation grating 2132C and the third modulation grating 2133C of the modulation grating layer 213C at the same time. That is to say, the incident range of the input monochromatic light 110 emitted by the monochromatic light source 10C needs to cover the areas where the first modulation grating 2131C, the second modulation grating 2132C and the third modulation grating 2133C are located at the same time, so as to ensure that the input monochromatic light 110 can propagate along the first optical path 201C, the second optical path 202C and the third optical path 203C respectively, and then provide the first, second and third output monochromatic lights 121, 122 and 123 in a time-sharing manner.

[0213] It is worth mentioning that, when one modulation grating is in a transmission state and the remaining two modulation gratings are in a diffraction state, the input monochromatic light 110 will be diffracted at the remaining two modulation gratings to be turned, and will be totally reflected in the total reflection substrate layer to propagate to the side surface of the light modulation component, and then reflected back into the light modulation component by the side surface of the light modulation component, which is prone to crosstalk. Therefore, in order to solve the above problem, according to the above third embodiment of the present invention, as Fig.19 As shown, the light modulation component 21C of the light conversion device 20C further includes a light absorption layer 216C, wherein the light absorption layer 216C is arranged on the side surface of the light modulation component 21C to absorb the light reflected to the side surface of the light modulation component 21C to prevent crosstalk.

[0214] Preferably, the light absorbing layer 216C is made of a light absorbing material coated on the side surface of the light modulation component 21 C. It is understood that the light absorbing material can be, but is not limited to, implemented as a black material such as black paint, black glue, etc.

[0215] It is worth noting that, although the monochromatic light source in the above-mentioned first, second and third embodiments and their variant examples of the present invention is an example of a blue laser source for emitting blue light, so that the input monochromatic light can be directly used as the third output monochromatic light without conversion, so as to achieve the purpose of providing RGB three-color light in time-sharing through the light conversion device. However, in other embodiments of the present invention, the input monochromatic light 110 emitted by the monochromatic light source can also be implemented as light with a smaller wavelength such as ultraviolet light (that is, the wavelength of the input monochromatic light 110 can be smaller than the wavelength of blue light), so that after the input monochromatic light 110 is converted into blue light, it can be used as the third output monochromatic light, and the purpose of providing RGB three-color light in time-sharing through the light conversion device can still be achieved.

[0216] Reference to the attached drawings of the specification Fig. 20 and 21 As shown, the micro-projection system 1D according to a fourth embodiment of the present invention is illustrated. Compared with the first embodiment of the present invention, the micro-projection system 1D according to the fourth embodiment of the present invention is different in that: Fig. 20 and Fig.21 As shown, the light conversion device 20D further includes a third quantum dot layer 24D, wherein the third quantum dot layer 24D is arranged in the third optical path 203 of the light conversion device 20D, and is used to convert the input monochromatic light 110D propagating along the third optical path 203 into the third output monochromatic light 123, so as to alleviate the color limitation of the light conversion device 20D on the monochromatic light source 10D.

[0217] Preferably, if Fig. 20 and Fig.21 As shown, the monochromatic light source 10D is implemented as an ultraviolet excitation source 12D for emitting ultraviolet light, so that the input monochromatic light 110D is implemented as ultraviolet light. At the same time, the third quantum dot layer 24D is implemented as a blue quantum dot layer 241D for converting ultraviolet light into blue light to ensure that the light conversion device 20D can still provide RGB three-color light. It can be understood that the red quantum dot layer and the green quantum dot layer (i.e., the first and second quantum dot layers 22, 23) can convert ultraviolet light into red light and green light respectively.

[0218] For example, Fig.21 As shown, the third quantum dot layer 24D is arranged in the second output area 2104 of the third light modulation unit 210c in the light modulation component 21 of the light conversion device 20D, so that the input monochromatic light 110D propagating along the third optical path 203 is converted into the third output monochromatic light 123 (such as blue light) by the third quantum dot layer 24D after being emitted from the second output area 2104 of the third light modulation unit 210c.

[0219] It is worth noting that, although the first and second output monochromatic lights 121, 122 pass through the third quantum dot layer 24D after being emitted from the second output region 2104 of the third light modulation unit 210c, quantum dots can only convert light with a shorter wavelength into light with a longer wavelength. Therefore, the first and second output monochromatic lights 121, 122 will not be converted into the third output monochromatic light 123 when passing through the third quantum dot layer 24D, so that the light conversion device 20D can still provide the first, second and third output monochromatic lights 121, 122, 123 in a time-sharing manner.

[0220] According to another aspect of the present invention, an embodiment of the present invention further provides a near-eye display device. Specifically, Fig. 22 As shown, the near-eye display device includes a near-eye display device body 600 and the at least one micro-projection system 1 (1A, 1C, 1D) mentioned above, wherein the micro-projection system is correspondingly arranged on the near-eye display device body 600, and is used to provide image light for the near-eye display device body 600, so as to transmit the image light provided by the micro-projection system 1 (1A, 1C, 1D) to the user's eyes through the near-eye display device body 600, so as to realize the near-eye display function.

[0221] It is worth mentioning that the type of the near-eye display device body 600 is not limited. For example, in an example of the present invention, Fig. 22 As shown, the near-eye display device body 600 can be implemented as a display waveguide 601 to transfer the image light provided by the micro-projection system 1 (1A, 1C, 1D) through the display waveguide, so that the user can view the image corresponding to the image light through the display waveguide to obtain an augmented reality experience. Of course, in other examples of the present invention, the near-eye display device body 600 can also be implemented as a reentrant display to transfer the image light provided by the micro-projection system 1 (1A, 1C, 1D) through the reentrant display, so that the user can view the image corresponding to the image light through the reentrant display to obtain an augmented reality experience.

[0222] According to another aspect of the present invention, an embodiment of the present invention further provides a light conversion method. Specifically, Fig.23 As shown, the photoconversion method comprises the steps of:

[0223] S110: modulating the input monochromatic light so that the input monochromatic light propagates along a first optical path, a second optical path, and a third optical path that do not completely overlap;

[0224] S120: converting the input monochromatic light propagating along the first optical path into a first output monochromatic light of a different color; and

[0225] S130: Convert the input monochromatic light propagating along the second optical path into a second output monochromatic light of a different color.

[0226] It is worth noting that in one example of the present invention, Fig.23 As shown, the photoconversion method may further include the steps of:

[0227] S140: directly use the input monochromatic light propagating along the third optical path as the third output monochromatic light.

[0228] In another example of the present invention, Fig.23 As shown, the photoconversion method may further include the steps of:

[0229] S140': converting the input monochromatic light propagating along the third optical path into a third output monochromatic light of a different color.

[0230] According to the above embodiments of the present invention, Fig.23 As shown, the photoconversion method may further include the steps of:

[0231] S150: switching on and off the first optical path, the second optical path, and the third optical path in a time-sharing manner, so as to provide the first output monochromatic light, the second output monochromatic light, and the third output monochromatic light with different colors in a time-sharing manner.

[0232] It is worth noting that although Fig.23 The step S120, the step S130, the step S140 (or the step S140') and the step S150 in the light conversion method shown are drawn in sequence, but the present invention does not limit the order of the step S120, the step S130, the step S140 (or the step S140') and the step S150.

[0233] According to another aspect of the present invention, an embodiment of the present invention further provides a micro-projection method. Specifically, Fig.24 As shown, the micro-projection method may include the steps of:

[0234] S210: emitting input monochromatic light having a predetermined color;

[0235] S220: Converting the input monochromatic light into a plurality of output monochromatic lights having different colors;

[0236] S230: Scanning the output monochromatic light into color image light; and

[0237] S240: Projecting the color image light to form an image.

[0238] It should be understood by those skilled in the art that the embodiments of the present invention described above and shown in the accompanying drawings are only examples and do not limit the present invention. The purpose of the present invention has been fully and effectively achieved. The functional and structural principles of the present invention have been demonstrated and explained in the embodiments, and the embodiments of the present invention may be deformed or modified in any way without departing from the principles.

Claims

1. A micro-projection system, characterized in that: include: a monochromatic light source, wherein the monochromatic light source is configured to emit input monochromatic light having a predetermined color; a light conversion device, wherein the light conversion device is used to convert the input monochromatic light from the monochromatic light source into a plurality of output monochromatic lights with different colors; a scanning unit, wherein the scanning unit is used to scan the output monochromatic light from the light conversion device into color image light; and a projection unit, wherein the projection unit is used to project the color image light from the scanning unit to form an image; Wherein, the light conversion device comprises a light modulation component, a first quantum dot layer and a second quantum dot layer, wherein the light modulation component has a first optical path, a second optical path and a third optical path which are not completely overlapped, and is used to modulate the input monochromatic light so that the input monochromatic light propagates along the first optical path, the second optical path and the third optical path respectively; wherein the first quantum dot layer is correspondingly located in the first optical path of the light modulation component, and is used to convert the input monochromatic light propagating along the first optical path into a first output monochromatic light of a different color; wherein the second quantum dot layer is correspondingly located in the second optical path of the light modulation component, and is used to convert the input monochromatic light propagating along the second optical path into a second output monochromatic light of a different color; Wherein, the optical modulation component includes at least one optical modulation unit, wherein the optical modulation unit includes a first total reflection substrate layer and a modulation grating layer, and the optical modulation unit has a total reflection optical path and a through optical path which are switched on and off in time division, wherein the modulation grating layer is superimposed on the first total reflection substrate layer, and the modulation grating layer is used to adjust the state of the optical modulation unit so that the optical modulation unit switches between a first state and a second state, wherein when the optical modulation unit is in the first state, the through optical path of the optical modulation unit is switched on and the total reflection optical path of the optical modulation unit is switched off; and when the optical modulation unit is in the second state, the through optical path of the optical modulation unit is switched off and the total reflection optical path of the optical modulation unit is switched on.

2. The micro-projection system according to claim 1, wherein: The modulation grating layer includes a first modulation grating and a second modulation grating arranged side by side, wherein the total reflection light path of the light modulation unit passes through the first modulation grating and the second modulation grating in sequence under the action of total reflection of the first total reflection substrate layer, so as to open or open the total reflection light path through the first modulation grating and the second modulation grating; wherein the through light path of the light modulation unit only passes through the first modulation grating under the action of transmission of the first total reflection substrate layer, so as to open or open the through light path through the first modulation grating.

3. The micro-projection system according to claim 2, wherein: The first and second modulation gratings of the modulation grating layer both have a transmission state and a diffraction state, and are used to switch the states of the first and second modulation gratings by adjusting the magnitude of the applied voltage, thereby regulating the state of the light modulation unit.

4. The micro-projection system according to claim 3, wherein: The light modulation unit has an input area, a first output area and a second output area, wherein the input area and the first output area both correspond to the first modulation grating of the modulation grating layer, and the second output area corresponds to the second modulation grating of the modulation grating layer.

5. The micro-projection system according to claim 4, wherein: The light modulation unit further includes a second total reflection substrate layer, wherein the second total reflection substrate layer is stacked on the modulation grating layer, and the modulation grating layer is located between the first total reflection substrate layer and the second total reflection substrate layer.

6. The micro-projection system according to claim 5, wherein: The input region and the second output region of the light modulation unit are arranged side by side on the second total reflection substrate layer of the light modulation unit, and the first output region is correspondingly arranged on the first total reflection substrate layer of the light modulation unit.

7. The micro-projection system according to claim 6, wherein: The first modulation grating and the second modulation grating are closely arranged between the first total reflection substrate and the second total reflection substrate, so that the total reflection light path of the light modulation unit is turned by total reflection only once in the first total reflection substrate layer.

8. The micro-projection system according to claim 6, wherein: The first modulation grating and the second modulation grating are arranged at intervals between the first total reflection substrate layer and the second total reflection substrate layer to form an air gap between the first modulation grating and the second modulation grating, so that the total reflection light path of the optical modulation unit can be turned by an odd number of total reflections within the first total reflection substrate layer.

9. The micro-projection system according to claim 6, wherein: The modulation grating layer further includes a light-transmitting spacer, wherein the light-transmitting spacer is arranged between the first modulation grating and the second modulation grating, and the total reflection light path of the light modulation unit passes through the light-transmitting spacer an even number of times, so that the total reflection light path is turned by total reflection in the first total reflection substrate layer and the second total reflection substrate layer respectively.

10. The micro-projection system according to claim 5, wherein: The first output region and the second output region of the light modulation unit are arranged side by side on the second total reflection substrate layer of the light modulation unit, and the input region is correspondingly arranged on the first total reflection substrate layer of the light modulation unit.

11. The micro-projection system according to claim 10, wherein: The modulation grating layer further includes a light-transmitting spacer, wherein the light-transmitting spacer is arranged between the first modulation grating and the second modulation grating, and the total reflection light path of the light modulation unit passes through the light-transmitting spacer an odd number of times, so that the total reflection light path is turned by total reflection in the first total reflection substrate layer and the second total reflection substrate layer respectively.

12. The micro-projection system according to claim 11, wherein: The material of the light-transmitting spacer is the same as that of the first and second modulation gratings.

13. The micro-projection system according to claim 11, wherein: The material of the light-transmitting spacer is the same as that of the first and second total-reflection substrate layers, and the light-transmitting spacer integrally connects the first and second total-reflection substrate layers.

14. The micro-projection system according to any one of claims 10 to 13, wherein: The at least one light modulation unit of the light modulation component includes a first light modulation unit, a second light modulation unit and a third light modulation unit, wherein the first light modulation unit, the second light modulation unit and the third light modulation unit are stacked together in sequence, respectively, wherein the first quantum dot layer is arranged between the first light modulation unit and the second light modulation unit, and the second quantum dot layer is arranged between the second light modulation unit and the third light modulation unit.

15. The micro-projection system of claim 14, wherein: The first quantum dot layer is correspondingly disposed in the second output region or the first output region of the first light modulation unit, and the second quantum dot layer is correspondingly disposed in the second output region or the first output region of the second light modulation unit.

16. The micro-projection system according to any one of claims 6 to 9, wherein: The at least one light modulation unit of the light modulation component includes a first light modulation unit, a second light modulation unit and a third light modulation unit, wherein the first light modulation unit, the second light modulation unit and the third light modulation unit are stacked together in sequence, respectively, wherein the first quantum dot layer is arranged between the first light modulation unit and the second light modulation unit, and the second quantum dot layer is arranged between the second light modulation unit and the third light modulation unit.

17. The micro-projection system of claim 16, wherein: The first quantum dot layer is correspondingly disposed in the second output region or the input region of the first light modulation unit, and the second quantum dot layer is correspondingly disposed in the second output region or the input region of the second light modulation unit.

18. The micro-projection system according to any one of claims 6 to 9, wherein: The at least one light modulation unit of the light modulation component includes a second light modulation unit and a third light modulation unit, and the light modulation component further includes a total reflection unit, wherein the total reflection unit, the second light modulation unit and the third light modulation unit are stacked together in sequence, wherein the first quantum dot layer is arranged between the total reflection unit and the second light modulation unit, and the second quantum dot layer is arranged between the second light modulation unit and the third light modulation unit.

19. The micro-projection system of claim 18, wherein: The total reflection unit includes a waveguide element, a coupling element and a coupling element, wherein the coupling element and the coupling element are arranged side by side on the same side of the waveguide element, and the coupling element and the coupling element correspond to the first modulation grating and the second modulation grating in the optical modulation unit respectively.

20. The micro-projection system of claim 19, wherein: The first quantum dot layer is correspondingly arranged at the out-coupling element or the in-coupling element of the total reflection unit, and the second quantum dot layer is correspondingly arranged at the second output region or the input region of the second light modulation unit.

21. The micro-projection system of claim 18, wherein: The total reflection unit is a total reflection prism, and the inclined surface of the total reflection prism faces the second light modulation unit, and the first quantum dot layer is correspondingly arranged on the inclined surface of the total reflection prism.

22. The micro-projection system according to any one of claims 4 to 13, wherein: The light modulation component further includes a coupling element, wherein the coupling element is correspondingly arranged in the input area of ​​the light modulation unit, and the coupling element is used to couple the input monochromatic light vertically or obliquely into the light modulation unit.

23. The micro-projection system of claim 1, wherein: The first optical path, the second optical path and the third optical path of the optical modulation component are turned on and off in a time-division manner.

24. The micro-projection system of claim 23, wherein: The first optical path, the second optical path, and the third optical path of the optical modulation component are partially overlapped end to end.

25. The micro-projection system according to any one of claims 1 to 13, wherein: The first quantum dot layer is a red quantum dot layer, and the second quantum dot layer is a green quantum dot layer.

26. The micro-projection system of claim 1, wherein: The light conversion device further includes a third quantum dot layer, wherein the third quantum dot layer is correspondingly arranged in the third optical path of the light modulation component, and is used to convert the input monochromatic light propagating along the third optical path into a third output monochromatic light of a different color.

27. The micro-projection system of claim 26, wherein: The third quantum dot layer is a blue quantum dot layer.

28. The micro-projection system of claim 1, wherein: The monochromatic light source is a blue laser source.

29. The micro-projection system of claim 26, wherein: The monochromatic light source is an ultraviolet laser source.

30. The micro-projection system as described in any one of claims 1 and 26 to 29, further comprising a driving control unit, wherein the driving control unit is communicatively connected to the monochromatic light source, the light conversion device and the scanning unit, respectively, for adjusting the emission intensity of the monochromatic light source to emit the input monochromatic light with a desired light intensity, adjusting the conversion state of the light conversion device to convert the input monochromatic light into the output monochromatic light with a desired color, and adjusting the scanning angle of the scanning unit to scan the output monochromatic light into a desired color image light.

31. A photoconversion method, characterized in that: Includes steps: Modulating the input monochromatic light by the light modulation component in the light conversion device so that the input monochromatic light propagates along a first light path, a second light path and a third light path that do not completely overlap; The input monochromatic light propagating along the first optical path is converted into a first output monochromatic light of a different color through a first quantum dot layer in the optical conversion device; as well as The input monochromatic light propagating along the second optical path is converted into a second output monochromatic light of a different color by a second quantum dot layer in the light conversion device; Wherein, the optical modulation component includes at least one optical modulation unit, wherein the optical modulation unit includes a first total reflection substrate layer and a modulation grating layer, and the optical modulation unit has a total reflection optical path and a through optical path which are switched on and off in time division, wherein the modulation grating layer is superimposed on the first total reflection substrate layer, and the modulation grating layer is used to adjust the state of the optical modulation unit so that the optical modulation unit switches between a first state and a second state, wherein when the optical modulation unit is in the first state, the through optical path of the optical modulation unit is switched on and the total reflection optical path of the optical modulation unit is switched off; and when the optical modulation unit is in the second state, the through optical path of the optical modulation unit is switched off and the total reflection optical path of the optical modulation unit is switched on.

32. The light conversion method as claimed in claim 31, further comprising the step of directly using the input monochromatic light propagating along the third optical path as the third output monochromatic light.

33. The light conversion method of claim 31, further comprising the step of converting the input monochromatic light propagating along the third optical path into a third output monochromatic light of a different color.

34. The light conversion method as described in claim 32 or 33 further comprises the step of: switching on and off the first light path, the second light path and the third light path in a time-sharing manner to provide the first output monochromatic light, the second output monochromatic light and the third output monochromatic light with different colors in a time-sharing manner.

35. A micro-projection method, characterized in that: Includes steps: emitting input monochromatic light having a predetermined color; converting the input monochromatic light into a plurality of output monochromatic lights having different colors; scanning the output monochromatic light into color image light; and projecting the color image light to form an image; The step of converting the input monochromatic light into a plurality of output monochromatic lights with different colors comprises the following steps: Modulating the input monochromatic light by a light modulation component in the light conversion device so that the input monochromatic light propagates along a first light path, a second light path and a third light path that do not completely overlap; The input monochromatic light propagating along the first optical path is converted into a first output monochromatic light of a different color through a first quantum dot layer in the optical conversion device; and The input monochromatic light propagating along the second optical path is converted into a second output monochromatic light of a different color by a second quantum dot layer in the light conversion device; Wherein, the optical modulation component includes at least one optical modulation unit, wherein the optical modulation unit includes a first total reflection substrate layer and a modulation grating layer, and the optical modulation unit has a total reflection optical path and a through optical path which are switched on and off in time division, wherein the modulation grating layer is superimposed on the first total reflection substrate layer, and the modulation grating layer is used to adjust the state of the optical modulation unit so that the optical modulation unit switches between a first state and a second state, wherein when the optical modulation unit is in the first state, the through optical path of the optical modulation unit is switched on and the total reflection optical path of the optical modulation unit is switched off; and when the optical modulation unit is in the second state, the through optical path of the optical modulation unit is switched off and the total reflection optical path of the optical modulation unit is switched on.

36. A near-eye display device, characterized in that include: A near-eye display device body; and At least one micro-projection system as described in any one of claims 1 to 30, wherein the micro-projection system is correspondingly arranged on the near-eye display device body to provide image light for the near-eye display device body.

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