CN110850669A

CN110850669A - Micro LED-based developing device and developing method thereof

Info

Publication number: CN110850669A
Application number: CN201910999959.3A
Authority: CN
Inventors: 孟玉凰; 楼歆晔; 黄河; 林涛
Original assignee: Shanghai Kun Yu Photoelectric Technology Co Ltd
Current assignee: Shanghai Kun Yu Photoelectric Technology Co Ltd; Shanghai North Ocean Photonics Technology Co Ltd
Priority date: 2019-07-29
Filing date: 2019-10-21
Publication date: 2020-02-28
Also published as: CN211956097U

Abstract

The invention relates to a micro LED-based imaging device for transmitting an image to a projection area, which comprises: the projector is arranged on the coupling-in part of the transmission element in a mode of emitting image light in an aligned mode, the coupling-in part receives and guides the image light to be transmitted, the coupling-out part outputs the image light outwards in an expanding mode, and an image entering the transmission layer from the coupling-in part is output to the light-out part in a total reflection mode so as to be transmitted to the projection area. In addition, the invention provides a projection device based on the MicroLED and a developing method thereof, which are arranged in a balanced manner in image generation and image transmission, and improve the final display quality.

Description

Micro LED-based developing device and developing method thereof

Technical Field

The present invention relates to the field of optical imaging, and in particular, to a projection apparatus and an imaging device, and an imaging method.

Background

The optical imaging device is an indispensable entertainment facility in modern life. From classical televisions, computers, mobile tablets, to smart phones, smart watches, and Augmented Reality (AR) and Virtual Reality (VR) are specific optical visualization applications. Some existing imaging devices are implemented using optical transmission or video transmission. More specifically, for the augmented reality technology, the optical transmission type has become a mainstream implementation mode due to its convenience of high resolution, no visual deviation, no time delay, and better conformity with social habits.

The light source and the light transmission path are equally important for the visualization device. In the case of clear and effective image information of the light-emitting element, light is reliably transmitted without loss or interference, and the final image has the best effect. Many current augmented reality display devices (AR) or Head-up display devices (Head-up) display images directly, and how much information a user can receive from a light source depends on the viewing position. In particular, in optical applications like Augmented Reality (AR) or Head-up (Head-up), ambient light from the outside interferes a lot, and the optical design is particularly important.

Most of the conventional optical imaging devices using optical transmission are designed based on Bird baths (Bird Bath) or free-form surface elements. However, the conventional optical developing device using the optical transmission type has the following drawbacks.

The conventional imaging device comprising optical elements is limited by the total optical distance, for example, the distance between lenses is set, and thus the imaging device cannot be thin and light enough, and the whole device cannot be made into a paper, a dial and glasses. In addition, due to the constraint of lagrange invariants, the exit pupil radius of the existing optical imaging device is limited, and the existing optical imaging device cannot be adapted to user groups with large pupil distance. In the generation of images, most of the existing image sources are a transmissive Liquid Crystal Display (LCD), a Digital Light Processor (DLP), a Digital Micro-Mirror device (DMD), a Liquid Crystal on Silicon (LCoS), an organic Light-Emitting Diode (OLED), and a Micro-electromechanical Scanning Mirror (MEMS Scanning Mirror), and so on. Such image sources have some drawbacks which are fatal to the overall visualization effect. In image transmission, optical images are lost in the transmission process after generation, and imaging effects such as brightness reduction, image deformation and the like are gradually reduced. Therefore, the viewpoint from image generation and the viewpoint from image transmission must be sufficiently considered so that the requirement for development is satisfied as a whole.

Specifically, in the aspect of an image source, passive projection such as LCoS, DLP, MEMS Scanning mirror and the like needs to use an additional light source, and then more devices need to occupy more space, so that the overall volume is not easy to further reduce, and the assembly cost is also high. The LCD and the OLED have the problems of low efficiency and brightness and large power consumption, and the OLED screen burning is still a great problem at present because the service life of organic materials is limited and the stability is great worry.

Disclosure of Invention

An object of the present invention is to provide a micro led-based developing device and a developing method thereof, in which image generation and image transmission are balanced, thereby improving final display quality.

Another object of the present invention is to provide a micro led-based display device and a display method thereof, which are suitable for application scenarios of augmented reality display (AR) or Head-up display (Head-up), and effectively provide optical display information.

Another object of the present invention is to provide a micro led-based display device and a display method thereof, which can reduce the overall volume occupation by effective optical design and is suitable for portable use.

Another object of the present invention is to provide a micro led-based developing device and a developing method thereof, in which an optical display is stably provided to meet the requirements of brightness, definition, and low power consumption.

Another object of the present invention is to provide a micro led-based developing device and a developing method thereof, in which an image is generated and then efficiently transmitted to be presented without external interference.

Another object of the present invention is to provide a micro led-based display device and a display method thereof, wherein the light transmission can be made of a material with high transmittance to visible light, and the device is suitable for the application scenario of augmented reality display (AR) or Head-up display (Head-up).

Another object of the present invention is to provide a micro led-based display device and a display method thereof, in which the device size is reduced while reducing the loss by using an efficient image transmission method.

Another object of the present invention is to provide a micro led-based imaging device and an imaging method thereof, wherein the image transmission mode provides multiple output modes to meet the requirements of different exit pupils (exit pupil radius or exit pupil distance).

Another object of the present invention is to provide a micro led-based display device and a display method thereof, in which image generation and transmission links are integrally configured and are linked to each other, thereby achieving a display effect beyond a general combination.

Another object of the present invention is to provide a micro led-based display device and a display method thereof, in which no additional energy is required for image transmission and overall power consumption is low.

Another object of the present invention is to provide a micro led-based developing device and a developing method thereof, in which an image is generated without using an external light source and an optical system is relatively simple.

Another object of the present invention is to provide a micro led-based developing device and a developing method thereof, in which image generation has high brightness, low power consumption, ultra-high resolution and color saturation.

Another object of the present invention is to provide a micro led-based developing device and a developing method thereof, in which image generation employs the MircoLED technology.

Another object of the present invention is to provide a micro led-based display device and a display method thereof, wherein the micro led has the greatest advantages from its greatest features, i.e., micron-scale pitch, addressing control and single-point driving light emission for each pixel (pixel). Compared with other display light sources, the current MicroLED has the highest luminous efficiency, and the space is greatly improved; in the luminous energy density, the MicroLED is the highest, and the space is also promoted. The former is beneficial to the energy saving of the display equipment, and the power consumption is about 10 percent of that of the LCD and 50 percent of that of the OLED; the latter can save the limited surface area of the display device and deploy more sensors, and the current theoretical result is that the MicroLED and the OLED achieve the same display brightness by only 10% of the coating area of the latter. Compared with an OLED which is also self-luminous, the brightness is 30 times higher and the resolution can reach 1500PPI (pixel density). The above advantages of the micro led help to solve the problems of low optical efficiency and reduced brightness of single-point output due to large exit pupil in imaging devices based on exit pupil expansion, since light is lost during coupling into and out of the waveguide and transmission. In addition, the Micro-LED is made of inorganic materials, has a simple structure and almost no light consumption, has very long service life and large cost reduction space. In recent years, the difficulty and cost of manufacturing micro leds have been greatly reduced due to advances in technology and advances in technology.

Another object of the present invention is to provide a micro led-based developing device and a developing method thereof, wherein the image transmission employs a waveguide technology.

Another object of the present invention is to provide a micro led-based imaging device and an imaging method thereof, wherein in the waveguide-based display scheme, a monochromatic or RGB image is injected into a waveguide, and then the thickness of an optical element is effectively reduced by using the total reflection transmission of light rays in a planar waveguide element, and the exit pupil expansion is achieved by controlling the step output of the image using one or more optical elements on the waveguide.

Additional advantages and features of the invention will be set forth in the detailed description which follows and in part will be apparent from the description, or may be learned by practice of the invention as set forth hereinafter.

In accordance with one aspect of the present invention, the foregoing and other objects and advantages are achieved in a projection apparatus comprising:

the image sensor comprises a light-emitting element and a projection lens, wherein the light-emitting element comprises at least one MicroLED and is controlled to emit image light, and the projection lens is used for collimating the light emitted by the light-emitting element.

According to one embodiment of the invention, the light emitting element is a micro led.

According to another aspect of the present invention, there is further provided a display apparatus for transmitting an image to a projection area, comprising:

the projection device and the transmission element are provided, wherein the transmission element comprises a coupling-in part, a conductive layer and a coupling-out part, wherein the projection device is controlled to emit image light, the coupling-in part receives and guides the image light to transmit, the coupling-out part outputs the image light outwards in an expanding manner, and the image entering the conductive layer from the coupling-in part is output to the coupling-out part in a total reflection manner.

According to an embodiment of the invention, wherein the transmission element is a waveguide device.

According to another aspect of the present invention, there is further provided a developing method comprising the steps of:

projecting image light by at least one micro LED;

collimating the image light; and

and transmitting the image light to project an image at a certain distance.

Further objects and advantages of the invention will be fully apparent from the ensuing description and drawings.

These and other objects, features and advantages of the present invention will become more fully apparent from the following detailed description, the accompanying drawings and the claims.

Drawings

Fig. 1 is a block diagram schematically illustrating a projection apparatus and a developing device according to a preferred embodiment of the present invention.

Fig. 2 is an optical schematic diagram of a projection apparatus, a developing device and a developing method thereof according to the above preferred embodiment of the present invention.

Fig. 3 is an optical schematic diagram of a projection apparatus, a developing device and a developing method thereof according to another possible mode of the above preferred embodiment of the present invention.

Fig. 4 is an optical schematic diagram of a projection apparatus, a developing device and a developing method thereof according to another possible mode of the above preferred embodiment of the present invention.

Fig. 5 is an optical schematic diagram of a projection apparatus, a developing device and a developing method thereof according to another possible mode of the above preferred embodiment of the present invention.

Fig. 6A is a schematic plan optical diagram of a light combiner of the projection apparatus according to the above feasible manner of the preferred embodiment of the present invention.

Fig. 6B is a schematic perspective optical diagram of a light combiner of the projection apparatus according to the above feasible manner of the preferred embodiment of the present invention.

Fig. 6C is a spectral distribution diagram of the light emitting element of the projection apparatus according to the above possible mode of the above preferred embodiment of the present invention.

Fig. 6D is a graph of the reflectivity of the surface film layer of the light combiner of the projection apparatus for different wavelengths according to the above feasible manner of the above preferred embodiment of the present invention, which illustrates the curves of the a surface in fig. 6A and 6B.

Fig. 6E is a graph illustrating the reflectivity curves of the surface film layers of the light combiner of the projection apparatus for different wavelengths according to the above feasible manner of the above preferred embodiment of the present invention, which illustrates the curves of the surface B in fig. 6A and 6B.

Fig. 7 is a schematic plan optical diagram of another optical combiner of the projection apparatus according to the above feasible manner of the above preferred embodiment of the present invention.

Fig. 8 is an optical schematic diagram of a projection apparatus, a developing device and a developing method thereof according to another possible mode of the above preferred embodiment of the present invention.

Fig. 9 is an optical schematic diagram of a projection apparatus, a developing device and a developing method thereof according to another possible mode of the above preferred embodiment of the present invention.

Fig. 10 is a schematic view of an application of the projection apparatus and the developing device according to the above preferred embodiment of the present invention.

Detailed Description

The following description is presented to disclose the invention so as to enable any person skilled in the art to practice the invention. The preferred embodiments in the following description are given by way of example only, and other obvious variations will occur to those skilled in the art. The basic principles of the invention, as defined in the following description, may be applied to other embodiments, variations, modifications, equivalents, and other technical solutions without departing from the spirit and scope of the invention.

It will be understood by those skilled in the art that in the present disclosure, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in an orientation or positional relationship indicated in the drawings for ease of description and simplicity of description, and do not indicate or imply that the referenced devices or components must be in a particular orientation, constructed and operated in a particular orientation, and thus the above terms are not to be construed as limiting the present invention.

It is understood that the terms "a" and "an" should be interpreted as meaning that a number of one element or element is one in one embodiment, while a number of other elements is one in another embodiment, and the terms "a" and "an" should not be interpreted as limiting the number.

The invention provides a display device which is controlled to display an image to a projection area. After being connected with image information, the imaging device emits image light, and then projects the image light in the projection area to image. It will be appreciated by those skilled in the art that the projection area may be a curtain, a human eye, or other carrier that receives image light. The application scenario of the display device is not limited in the present invention.

It should be noted that the components can be combined and replaced in different structures between different feasible manners of the preferred embodiment provided by the invention, and the following examples are only used for specific description.

As shown in fig. 1 to fig. 2, the image display apparatus according to a preferred embodiment of the present invention includes a projection device 100 and a transmission element 30, wherein the transmission element 30 is disposed on a proximal side of the projection device 100. After the projection device 100 generates the image light, the image light is transmitted through the transmission element 30 and output at a certain distance, so as to be presented in the projection area.

Specifically, the projection apparatus 100 includes a light emitting device 10 and an optical lens. The light emitting element 10 is capable of receiving an image signal to produce image light, that is, a photoelectric conversion device. The image light projected from the light emitting element 10 through the optical lens and the transmission element 30 can be directly imaged in the projection area.

It should be noted that the optical lens is embodied as a projection lens 20 in the preferred embodiment, and the optical lens 20 is further a collimating lens according to different design requirements.

More specifically, the transmission element 30 includes a coupling-in part 31, a conductive layer 32 and a coupling-out part 33, wherein the image light emitted from the projection apparatus 100 is directed toward the coupling-in part 31, and the image entering the conductive layer 32 from the coupling-in part 31 is reflected and output to the coupling-out part 33, so as to transmit the image to the projection area. The out-coupling part 33 of the transfer element 30 is extended to the in-coupling part 31 to form a passage for transferring image light between the in-coupling part 31 and the out-coupling part 33. That is, the image light enters the conductive layer 32 from the coupling-in part 31 to the coupling-out part 33 to be output.

In one possible approach, the light emitting element 10 is a micro led device and the transmission element 30 is a waveguide device. The image display device includes the light emitting element 10, the projection lens 20, the conductive layer 32, the coupling-in member 31, and the coupling-out member 33.

The light emitting element 10 is used to provide a high-luminance, high-contrast monochrome or RGB image.

The projection lens 20 is configured to collimate the light beam emitted by the light emitting device 10 into a parallel light beam, and form the projection apparatus together with the light emitting device 10. The projection lens 20 may be one or more lenses, or a combination of reflective and transmissive optical elements, or the like. For example, six or more collimating lenses.

The incoupling component 31 is used for coupling the output light of the projection device into the conducting layer 32.

The conductive layer 32 is used for totally reflecting the light coupled in from the coupling-in part 31 to propagate to the coupling-out part 33.

The coupling-out part 33 is configured to partially output and partially transmit the light totally reflected in the conducting layer 32 each time the light contacts the coupling-out part 33, the output light is coupled out of the waveguide to the projection area, and the directly transmitted part continues to be totally reflected in the conducting layer 32 until the light is coupled and output, thereby completing exit pupil expansion.

Preferably, the conductive layer 32 is a waveguide substrate.

Preferably, the incoupling component 31 is an incoupling optical element. The outcoupling means 33 are outcoupling optical elements. That is, the output light of the projection lens 20 is coupled into the conductive layer 32 of the transmission element 30.

Preferably, the light emitting element 10 is a micro led micro display screen.

Specifically, fig. 1 is a block diagram of the projection apparatus and the display device. The light emitting device 10 and the projection lens 20 form the projection apparatus, an output image of the projection apparatus enters the coupling-in part 31 and is coupled and input into the conductive layer 32, and total reflection is performed in the conductive layer 32 for multiple times until the coupling-out part 33 is coupled out and enters the projection area, thereby completing a display process.

As shown in fig. 2, the present preferred embodiment provides a developing method including the steps of:

A. projecting image light by at least one micro LED;

B. collimating the image light; and

C. and transmitting image light to project an image at a certain distance.

Specifically, the display device includes the projection apparatus 100 composed of the light emitting element 10 and the projection lens 20, the coupling-in member 31, the conductive layer 32, and the coupling-out member 33. The light emitting element 10 serves as an image source for displaying a monochrome or RGB image, i.e., step a. The image light rays from the pixels of the image are collimated into parallel beams by the projection lens 20, i.e., step B. After the parallel light beams are diffracted by the coupling-in part 31, the light rays of the first diffraction order meet the total reflection condition of the waveguide, are totally reflected in the conducting layer 32 and advance to the coupling-out part 33, are diffracted by the partial transmission part each time the coupling-out part 33 is contacted, the diffracted light is coupled out of the conducting layer 32 to reach the projection area, and the direct transmission part continues to be totally reflected in the conducting layer 32 and advance until being diffracted and coupled out, enters the projection area, so that the expansion of the exit pupil is completed. Namely step C.

Preferably, the coupling-in part 31 is implemented as an input diffractive optical element.

Preferably, the outcoupling means 33 is implemented as an output diffractive optical element.

The micro display screen can be a single color or a full color RGB light-emitting element 10, and can respectively realize a single color display and a full color display. The projection lens 20 may be one or more lenses, or a combination of reflective and transmissive optical elements, or the like. The incoupling means 31 may be selected from a blazed grating, an asymmetric surface relief grating or other diffractive structure with high coupling efficiency. The conductive layer 32 may be a flat plate structure made of an optical material transparent to visible light, and the upper and lower surfaces thereof are parallel. The coupling-in part 31/the coupling-out part 33 can be tightly attached to the surface of the conductive layer 32, and can also be embedded in the material of the conductive layer 32; the outcoupling means 33 employs a periodic structure with low coupling diffraction efficiency to ensure continuous light energy output during exit pupil expansion.

The optimal embodiment utilizes the advantages of self luminescence, high brightness, low power consumption, high resolution, high color saturation and long service life of the MicroLED, combines the characteristic of waveguide display of specific total reflection transmission and exit pupil expansion, can effectively make up the advantages of high brightness and low power consumption of the MicroLED, and can effectively make up the problem that the optical efficiency of a waveguide display device expanded by an exit pupil is low, and the large exit pupil enables a short plate with reduced single-point output brightness, so that the augmented reality display with high brightness, low power consumption, small size, large window and good stability can be finally realized.

The transmission element 30 may in particular be a diffractive optical waveguide or a geometric optical waveguide.

The coupling-in part 31 of the diffractive optical waveguide is optimally designed to have high coupling diffraction efficiency for improving the efficiency of the display system and reducing power consumption. The incoupling means 31 may be selected from a blazed grating, an asymmetric surface relief grating or other diffractive structure with high coupling efficiency.

The conducting layer 32 of the diffractive optical waveguide can adopt a flat plate structure made of optical materials transparent to visible light, and the upper surface and the lower surface of the flat plate structure are parallel; the coupling-in part 31/the coupling-out part 33 can be closely attached to the surface of the conductive layer 32, or can be embedded in the material of the conductive layer 32.

The coupling-out part 33 of the diffractive optical waveguide adopts a periodic structure with low coupling diffraction efficiency to ensure continuous light energy output in the process of exit pupil expansion.

The coupling-in part 31 of the geometric optical waveguide can be a reflecting surface or a prism, which has high coupling efficiency and is used for improving the efficiency of the display system and reducing the power consumption of the system.

The outcoupling means 33 of the geometrical light guide may be an "optical combiner", which may typically consist of an array of partially transmissive and partially reflective mirrors embedded inside the conducting layer 32 and forming a certain angle with the transmitted light beam inside the waveguide, while each mirror is coated with an optical film of a corresponding reflection-transmission ratio.

In order to realize full-color display, the light emitting element 10 may use RGB full-color, and the RGB color image output from the light emitting element is input to the transfer element 30 and then coupled and output to the projection region via the transfer element 30. The RGB full-color MicroLED can be obtained by an RGB three-color LED method, each pixel comprises three RGB three-color LEDs, P and N electrodes of the three-color LEDs are connected with a circuit substrate generally in a bonding or flip mode, then a special LED full-color driving chip is used for carrying out Pulse Width Modulation (PWM) current driving on each LED, and the PWM current driving mode can realize digital dimming by setting a current effective period and a duty ratio; the RGB full-color MicroLED can also be realized by a UV/blue light LED + luminous medium method, wherein if the UV MicroLED is used, red, green and blue luminous media need to be excited to realize RGB three-color matching; if the blue light MicroLED is used, red and green light-emitting media are needed to be matched. Luminescent media can be generally classified into phosphors and Quantum Dots (QDs). The nano material fluorescent powder can emit light with specific wavelength under the excitation of a blue light or ultraviolet light LED, and the light color is determined by the fluorescent powder material and is simple and easy to use, so that the fluorescent powder coating method is widely applied to LED illumination and can be used as a typical micro LED colorization method. The fluorescent powder is generally coated on the surface of a sample by a spin coating or dispensing method after the micro LED is integrated with a driving circuit. The particle size of the quantum dots is generally between 1 nm and 10nm, and the quantum dots can be suitable for micro-display with smaller size. The quantum dots also have the effects of electroluminescence and photoluminescence, can emit fluorescence after being excited, and the luminescent color is determined by materials and sizes, so that different luminescent wavelengths of the quantum dots can be changed by regulating and controlling the particle size of the quantum dots. When the particle size of the quantum dot is smaller, the luminescent color is more blue; when the quantum dots are larger, the emission color is more red. The chemical composition of the quantum dots is various, and the luminescent color can cover the whole visible region from blue light to red light. And has the characteristics of high absorption-luminous efficiency, narrow full width at half maximum, wide absorption spectrum and the like, thereby having high color purity and saturation. And the structure is simple, the device is thin and can be curled, and the device is very suitable for micro-display application. The quantum dot technology can be developed by adopting a rotary coating and mist spraying technology, namely, quantum dots with uniform and controllable sizes can be sprayed by using a sprayer and airflow control. The coating is coated on a UV/blue light LED, so that the UV/blue light LED can be excited to emit RGB three-color light, and full color is realized through color matching.

In addition, the preferred embodiment also provides other simpler and easier-to-implement methods for realizing the micro led-based full-color display. Illustratively, a two-color light emitting element 10 and a single-color light emitting element 10 can be used, and the two-color image and the single-color image respectively output by the two-color light emitting element and the single-color light emitting element are optically synthesized, input to the transmission element 30, and then coupled and output to the projection area through the transmission element 30; it is also possible to use R, G, B three single-color light emitting elements 10, and the R, G, B single-color images output by the light combining device 19 are optically combined, input to the transmission element 30, and then coupled and output to the projection area via the transmission element 30. The light combiner 19 is made by bonding prisms with different coatings. Exhibit different transmission or reflection characteristics for different wavelengths of incident light. R, G, B, the three single color images are incident on the light combiner 19 from a specific direction, and combined to form a single RGB full-color image.

The beneficial effects of the preferred embodiment are: the micro LED is matched with the waveguide display, one plus one is larger than two, the advantages of self luminescence, high brightness, low power consumption, high resolution and color saturation and long service life of the micro LED are fully utilized, and the characteristic of total reflection transmission and exit pupil expansion of the waveguide display is combined, so that the augmented reality display device with high brightness, low power consumption, small size, large window and good stability is realized. This preferred embodiment has also provided a plurality of full-color waveguide display methods based on micro led, can adopt the full-color of RGB the light emitting component 10, or use a double-colored light emitting component 10 and a monochromatic light emitting component 10 carry out optics and close the look, or use R, G, B three monochromatic light emitting component 10 carry out optics and close the look, cooperate with transmission element 30, realized a simple structure, luminance is very high, the volume is very little, the energy consumption is very low, the full-color augmented reality display system that the image quality is good. Other possibilities of the preferred embodiment are set forth in detail below.

A display device according to another possible embodiment of the present invention is illustrated, as shown in fig. 3, wherein the display device includes a light emitting element 10, a projection lens 20 and a transmission element 30, wherein the structure of the light emitting element 10 is similar to that of the light emitting element 10 of the display device of the above preferred embodiment in fig. 2, and the description of the present invention is omitted.

The preferred embodiment can be applied to waveguide augmented reality devices with different architectures, such as the imaging device shown in fig. 3. The transmission element 30 includes a coupling-in part 31 having a reflective surface for receiving and coupling the parallel light beams projected by the projection apparatus 100. The conductive layer 32 continuously reflects the coupled light to the out-coupling structure. The outcoupling means 33, which may generally consist of an array of partially transmissive and partially reflective mirrors, are embedded inside the conducting layer 32 and form a specific angle with the propagating light beam in the waveguide, while each mirror is coated with a film with a corresponding reflection-transmission ratio. Specifically, the light beam emitted from the light emitting device 10 in monochrome or full color RGB is collimated into a parallel light beam by the projection lens 20, coupled into the waveguide by the coupling-in part 31, and undergoes multiple rounds of total reflection in the conductive layer 32 until the light beam travels to the coupling-out part 33, and each mirror surface in the coupling-out part 33 reflects part of the light beam out of the conductive layer 32 into the projection area, while the rest of the light beam is transmitted to continue to travel in the conductive layer 32. This portion of the advancing light then encounters another mirror, and the above "reflection-transmission" process is repeated until the last mirror in the mirror array reflects all of the remaining light out of the conductive layer 32 into the projection area. The geometric optical waveguide realizes exit pupil expansion according to the scheme, and is matched with the micro LED, so that augmented reality display with high brightness, low power consumption, small size, large window and good stability can be realized.

In order to realize full-color display, an RGB full-color micro LED micro display screen may be used, and the RGB full-color micro LED may be obtained by an RGB three-color LED method or a UV/blue LED + light-emitting medium method. In addition, the invention also provides other simpler and easier-to-implement methods for realizing the full-color display based on the MicroLED.

A display device of another possible mode of the present invention is illustrated, as shown in fig. 4, wherein the display device includes a light emitting element 10, a projection lens 20 and a transmission element 30, and the structures of the projection lens 20 and the transmission element 30 are similar to those of the projection lens 20 and the transmission element 30 of the display device of the above preferred embodiment in fig. 2, and the detailed description of the present invention is omitted.

As shown in fig. 4, is the projection device based on a two-color first light emitting element 11 and a single-color second light emitting element 12. The number of the light emitting elements 10 is two, and one bicolor first light emitting element 11 can be a red-green micro LED, a red-blue micro LED or a blue-green micro LED. The second light emitting element 12 is a single color micro led, which may be a blue micro led, a green micro led or a red micro led, respectively. The first light emitting element 11 and the second light emitting element 12 are combined by a light combiner 19. The light combiner 19 may be a planar optical element coated with a specific thin film, and is disposed at 45 ° and-45 ° with respect to the first light emitting element 11 and the second light emitting element 12, respectively. Due to the wavelength selectivity of the coating, the light combiner 19 transmits the light beam emitted by the first light emitting element 11 and reflects the light beam emitted by the second light emitting element 12. Similarly, according to different coating methods, the light combiner 19 may also transmit the light beam emitted by the second light emitting element 12 and reflect the light beam emitted by the first light emitting element 11. The image after optical color combination is collimated by the projection lens 20, input to the transmission element 30, and then coupled and output to the projection area through the transmission element 30, so that full-color display is realized. The transmission process of the light beam in the transmission element 30 is the same as that of the above embodiment, the transmission element 30 may be a diffractive optical waveguide or a geometric optical waveguide, fig. 4 is a diffractive optical waveguide, which illustrates a full-color imaging device based on a two-color micro led and a single-color micro led, and the invention includes but is not limited to this example.

A display device according to another possible embodiment of the present invention is illustrated, as shown in fig. 5 to 7, wherein the display device includes a light emitting element 10, a projection lens 20 and a transmission element 30, and the structures of the projection lens 20 and the transmission element 30 are similar to those of the projection lens 20 and the transmission element 30 of the display device of the preferred embodiment shown in fig. 2, and the description of the present invention is omitted.

As shown in fig. 5, is a developing device based on R, G, B three single-color light emitting elements 10. The first light emitting element 11 is a blue micro led, the second light emitting element 12 is a green micro led, the third light emitting element 13 is a red micro led, and the three single-color light emitting elements 10 are combined by the light combiner 19. The light combiner 19 is made by bonding prisms with different coatings. Exhibit different transmission or reflection characteristics for different wavelengths of incident light. R, G, B, the three single color images are incident on the light combiner 19 from a specific direction, and combined to form a single RGB full-color image. As an example, with reference to fig. 5, a first thin film plated on a first surface of the light combiner 19 reflects the blue light beam emitted from the first light emitting device 11, and a second thin film plated on a second surface reflects the red light beam emitted from the third light emitting device 13, and simultaneously, the green light beam emitted from the second light emitting device 12 passes through the light combiner 19. According to different placement modes of the light combiner 19, the light-emitting elements 10 of three single colors are also correspondingly placed at corresponding positions, so that R, G, B single color images are ensured to be respectively incident to the light combiner 19 from specific directions. The RGB image optically combined by the light combiner 19 is collimated by the projection lens 20, input to the transmission element 30, and then coupled and output to the projection area by the transmission element 30, so that full-color display is realized. The transmission process of the light beam in the transmission element 30 is the same as that of the above-mentioned embodiment, the transmission element 30 can be a diffractive optical waveguide or a geometric optical waveguide, fig. 5 is a diffractive optical waveguide, which shows a developing device based on R, G, B monochromatic light-emitting elements 10, and the invention includes but is not limited to this example.

Table 1 lists the relevant parameters of the micro led microdisplay in this embodiment. Table 2 lists some of the system parameters for this example.

TABLE 1

TABLE 2

Fig. 6A shows a schematic plan view of one such light combiner 19. The light combiner 19 comprises a plurality of light combining elements 191, for example, in this embodiment, it comprises four light combining elements 191 implemented as right-angle prisms, i.e. the light combiner 19 is formed by gluing four right-angle prisms coated with specific optical films. Plating a red light reflecting film on a first diagonal surface (surface A) shown in the figure, and reflecting a red light beam emitted by the red MicroLED and having a center direction along a first direction; a blue light reflecting film is plated on the surface of the second diagonal surface, namely the surface B, and is used for reflecting blue light beams emitted by the blue MicroLED along the second direction in the central direction; for a green light beam emitted by the green micro led and having a center direction along the third direction, the light combiner 19 transmits the green light beam, and the propagation direction of the light beam is unchanged. Wherein, the surface A and the surface B are vertical to each other. R, G, B, the three monochromatic images are incident on the light combiner 19 from the specific direction, and the combined colors become a single RGB full-color image, and the center direction of the combined image is along the third direction.

Fig. 6B shows a three-dimensional schematic diagram of the light combiner 19 at R, G, B.

Fig. 6C shows the spectral distribution of the three-color micro led in this example.

Fig. 6D shows the reflectance of the a-surface film layer for different wavelengths in this example.

Fig. 6E shows the reflectance of the B-surface film layer for different wavelengths in this example.

The light combiner 19 may take many forms and fig. 7 shows another R, G, B schematic plan view of the light combiner 19. The light combiner 19 includes a plurality of light combining elements 191, and more specifically, includes three light combining

prisms

1911, 1912 and 1913 corresponding to the three prisms coated with the specific optical film, so that the light combiner 19 is formed by gluing the three prisms coated with the specific optical film. Specifically, a red light beam emitted by the red micro led is totally reflected by the second surface 19112 of the first light combining prism 1911 after entering, reflected to the first surface 19111 of the first light combining prism 1911, and then reflected by the plated optical film. After entering, a blue light beam emitted by the blue micro led is totally reflected at a fine air gap between the first light combining prism 1911 and the second light combining prism 1912, and is reflected to the first surface 19121 of the second light combining prism 1912 and then reflected by the plated optical film. The green light beam emitted from the green micro led enters the third light combining prism 1913, is transmitted and propagated in the light combiner 19, and finally exits from the second surface 19112 of the first light combining prism 1911. R, G, B, the three single color images are incident on the light combiner 19 from a specific direction, and combined to form a single RGB full-color image. The positions and the directions of the R, G, B three monochromatic micro LEDs are flexibly arranged according to the prism angle and the placement mode in the light combiner 19.

A display device of another possible mode of the present invention is illustrated, as shown in fig. 8, wherein the display device includes a light emitting element 10, a projection lens 20 and a transmission element 30, wherein the structures of the light emitting element 10 and the projection lens 20 are similar to the light emitting element 10 and the projection lens 20 of the display device of the above preferred embodiment in fig. 5, and the detailed description of the present invention is omitted.

For the development equipment, three-color light is transmitted by using a single-layer waveguide, crosstalk is easy to occur, problems such as dispersion and ghost image are caused, and the difficulty of optical design is increased. The preferred embodiment provides a solution to the above-mentioned problems. As shown in fig. 8, a development device based on R, G, B three single-color micro leds. The light beams emitted by the first light emitting element 11, the second light emitting element 12, and the third light emitting element 13 are combined by the light combiner 19 to form an RGB full-color image, and then collimated by the projection lens 20 and input to the transmission element 30. The transmission element 30 comprises two layers of the same conductive layer 32, but two layers of the conductive layer 32 are designed for different incident wavelengths. Illustratively, a first layer of the conductive layer 321 is designed for red light and a second layer of the conductive layer 322 is designed for blue-green light. The red light component in the RGB image is diffracted by the first layer of the coupling-in component 311, then totally reflected in the first layer of the conductive layer 321, goes to the first layer of the coupling-out component 331, and finally is diffracted and coupled out to enter the projection area; the blue-green light component in the RGB image is diffracted by the second layer of the coupling-in component 312, then totally reflected in the second layer of the conductive layer 322, goes to the second layer of the coupling-out component 332, and finally is diffracted and coupled out to enter the projection area. By the double-layer waveguide display device based on R, G, B three single-color micro LEDs, high-image-quality and small-aberration full-color display is achieved. Similarly, the first waveguide may be designed for blue light, the second waveguide may be designed for red light and green light, and three layers of waveguides may be used to transmit red light, green light, and blue light, respectively. Fig. 8 illustrates a diffractive optical waveguide, which shows a full-color double-layer waveguide imaging device based on R, G, B three single-color micro leds, in fact, the transmission element 30 may be a diffractive optical waveguide or a geometric optical waveguide, and a full-color image may be provided by using RGB full-color micro led light-emitting elements 10, or using one dual-color micro led light-emitting element 10 and one single-color micro led light-emitting element 10, or using R, G, B three single-color micro led light-emitting elements 10, including but not limited to this example.

More specifically, in the preferred embodiment, the display device of the present invention includes a light emitting element 10, a projection lens 20 and a transmission element 30, wherein the light emitted from the light emitting element 10 is guided to the transmission element 30 through the projection lens 20, and finally guided out from the transmission element 30. Preferably, the light emitting element 10 is a three-color micro led, as shown in fig. 9. It is worth mentioning that the transmission element 30 outputs an image to the outside for the user to view, and the viewing position of the user is not limited. That is, the position and angle of viewing by the user are not limited for the output of the visualization device. More, the image display device further includes a light combiner 19, and the light combiner 19 is disposed on the light emitting element 10 for transmitting the light passing through the light combiner 19 to the projection lens 20.

The light emitting surface of the light combiner 19 is disposed opposite to the projection lens 20, and the light emitting surface of the projection lens 20 is disposed opposite to the transmission element 30. That is, the light emitted from the light emitting element 10 is unidirectionally guided to the transmission element 30 to form an image optical path. In the preferred embodiment, the light emitting elements 10 are three single-color R, G, B three single-color micro leds, which are referred to as a first light emitting element 11, a second light emitting element 12, and a third light emitting element 13 for convenience of description. The first light emitting element 11, the second light emitting element 12, and the third light emitting element 13 are respectively disposed in different specific directions of the light combiner 19. The first light-emitting element 11, the second light-emitting element 12, and the third light-emitting element 13 are controlled to emit light, and may be individual light or monochromatic images. As shown in fig. 9, the light combiner 19 is a color combining prism, and can emit a full-color image. It is understood that the positions and angles of the first light emitting element 11, the second light emitting element 12, and the third light emitting element 13 are arranged in accordance with the position of the light combiner 19.

The transmission element 30 includes a coupling-in part 31, a conductive layer 32 and a coupling-out part 33, wherein the coupling-in part 31 and the coupling-out part 33 are preset on the side of the conductive layer 32. In the preferred embodiment, the transmission element 30 includes three conductive layers 32, three coupling-in portions 31 and three coupling-out portions 33, respectively. Compared to the previous preferred embodiment, each of the conductive layers 32, i.e. the first conductive layer 321, the second conductive layer 322, and the third conductive layer 323, respectively, conducts light of different wavelength bands, thereby avoiding the problems of crosstalk, dispersion, ghost image, etc. For example, the first conductive layer 321 is for red light, the second conductive layer 322 is for blue light, and the third conductive layer 323 is for green light. That is, after the image is emitted by the first light emitting element 11, the second light emitting element 12, and the third light emitting element 13, the image is processed by the light combiner 19 and the projection lens 20, then respectively transmitted by the transmission element 30, and finally diffracted and coupled out to form the projection area, so as to display the image.

Each of the conductive layers 32 of the preferred embodiment has the respective coupling-in part 31 and the coupling-out part 33, which are referred to as a first coupling-in part 311, a second coupling-in part 312, and a third coupling-in part 313, and a first coupling-out part 331, a second coupling-out part 332, and a third coupling-out part 333. Preferably, each of said coupling-in members 31 and each of said coupling-out members 33 is designed for a different wavelength and for the respective said conductive layer 33, respectively. That is, each of the coupling-in parts 31 and each of the coupling-out parts 33 are separately processed and then projected to a distance away through the different conductive layers 32.

Further, as shown in fig. 10, the projection device 100 and the transmission element 30 are integrated into a pair of wearable glasses.

It will be appreciated by persons skilled in the art that the embodiments of the invention described above and shown in the drawings are given by way of example only and are not limiting of the invention. The objects of the invention have been fully and effectively accomplished. The functional and structural principles of the present invention have been shown and described in the examples, and any variations or modifications of the embodiments of the present invention may be made without departing from the principles.

Claims

1. A micro led-based visualization device for transmitting an image to a projection area, comprising:

the projection device comprises a light-emitting element and a projection lens, wherein at least one MicroLED of the light-emitting element is controlled to emit image light, and the projection lens is used for collimating the light emitted by the light-emitting element; and

a transmission element, wherein the transmission element comprises a coupling-in part, a conductive layer and a coupling-out part, wherein the projection device is controlled to emit image light, the coupling-in part receives and guides the image light to transmit, the coupling-out part outputs the image light outwards in an expanding manner, and the image entering the conductive layer from the coupling-in part is output to the coupling-out part in a total reflection manner.

2. The visualization device of claim 1, wherein the configuration of the MicroLED of the light emitting element is selected from the group consisting of: the LED comprises a three-color MicroLED, at least three single-color MicroLEDs, at least one double-color MicroLED and a single-color MicroLED matched with the at least one double-color MicroLED.

3. The display apparatus according to claim 1, wherein the light-emitting element comprises three single-color micro leds, and the projection device further comprises a light combiner which transmits a portion of the light emitted from the single-color micro leds and reflects a remaining portion of the light emitted from the single-color micro leds, so that the light emitted from the three single-color micro leds forms full-color image light after passing through the light combiner.

4. The image display apparatus according to claim 3, wherein the light combiner comprises four right-angle prisms coated with a coating film and forms two diagonal surfaces perpendicular to each other, wherein the light split by two of the single-color MicroLEDs respectively reaches the two diagonal surfaces and is reflected, and the other single-color MicroLED is transmitted by the right-angle prisms.

5. The display apparatus according to claim 3, wherein the light combiner comprises three light combining prisms with coatings, light emitted by two of the single-color micro LEDs is incident on two of the light combining prisms respectively and then reflected to change the light path, light emitted by another single-color micro LED is incident on the remaining light combining prisms and then transmitted, and forms the full-color image light with the reflected light emitted by the two single-color micro LEDs.

6. The display apparatus according to claim 1, wherein the light-emitting element comprises a dual-color micro led and a single-color micro led, and the projection device further comprises a light combiner, which transmits light emitted from the single-color micro led and reflects light emitted from the dual-color micro led, so that light emitted from the light-emitting element passes through the light combiner to form full-color image light.

7. The display apparatus according to claim 1, wherein the light-emitting element comprises a dual-color micro led and a single-color micro led, and the projection device further comprises a light combiner for reflecting light emitted from the single-color micro led and transmitting light emitted from the dual-color micro led, so that light emitted from the light-emitting element passes through the light combiner to form full-color image light.

8. An imaging device according to claim 6, wherein the light combiner comprises a planar optical element with a coating disposed at 45 ° and-45 ° to the bi-color MicroLED and the mono-color MicroLED, respectively.

9. An imaging device according to claim 7, wherein the light combiner comprises a planar optical element with a coating disposed at 45 ° and-45 ° to the bi-color MicroLED and the mono-color MicroLED, respectively.

10. The developing device according to claim 1, wherein the micro LED of the light emitting element connects P and N electrodes of a three-color LED with a circuit substrate in one manner selected from bonding and flip-chip.

11. The developing device according to claim 1, wherein the light emitting element is selected from one of a uv LED and a blue LED coated with a nano material phosphor to output full color image light.

12. The developing device according to claim 1, wherein the micro led of the light emitting element outputs one selected from a group consisting of a monochrome image light, a bi-color image light, and a full-color image light.

13. An imaging apparatus according to any one of claims 1 to 12, wherein the transmission element is a waveguide device, and the conductive layer for transmitting light is selected from one of a single-layer waveguide, a double-layer waveguide, and a triple-layer waveguide, wherein the multiple layers of waveguides are disposed one on top of the other.

14. An imaging device according to any one of claims 1 to 12, wherein the outcoupling means is constituted by an array of partially transmissive and partially reflective mirrors.

15. A display device according to any one of claims 1 to 12, wherein said conductive layer and said outcoupling means transmit light in a repetitive reflection and transmission manner.

16. An imaging device according to any one of claims 1 to 12, wherein the conductive layer is selected from one of a diffractive optical waveguide and a geometric optical waveguide.

17. A method of imaging comprising the steps of:

projecting image light by at least one light emitting element;

collimating the image light; and

the image light is transmitted reflectively for projection at a distance.

18. The visualization method according to claim 18, wherein the light emitting element is a micro led, and wherein a waveguide device is used for transmitting the image light.

19. The method for displaying images according to claim 18, wherein the light emitting element comprises a light combiner, wherein the light emitting element comprises three single-color micro leds, and the light emitting element transmits a portion of the light emitted from the single-color micro leds and reflects a remaining portion of the light emitted from the single-color micro leds, so that the light emitted from the three single-color micro leds forms full-color image light after passing through the light combiner.

20. The developing method according to claim 19, wherein the light combiner comprises four right-angle prisms with coatings, and forms two orthogonal planes, wherein the light separated by two of the single-color micro leds respectively reaches the two orthogonal planes and is reflected, and the other single-color micro led is transmitted by the right-angle prisms.

21. The developing method according to claim 19, wherein the light combiner comprises three light combining prisms with coatings, light emitted by two of the single-color micro leds respectively enters two of the light combining prisms and is reflected to change a light path, light emitted by another single-color micro led enters the remaining light combining prisms and is transmitted, and the reflected light emitted by the two single-color micro leds form the full-color image light.

22. The method of claim 18, wherein the light-emitting element comprises a dual-color micro led and a single-color micro led coupled to the dual-color micro led, and the projection apparatus further comprises a light combiner that transmits light emitted from the single-color micro led and reflects light emitted from the dual-color micro led so that the light emitted from the light-emitting element passes through the light combiner to form full-color image light.

23. The method of claim 18, wherein the light-emitting element comprises a dual-color micro led and a single-color micro led coupled to the dual-color micro led, and the projection apparatus further comprises a light combiner for reflecting light emitted from the single-color micro led and transmitting light emitted from the dual-color micro led, so that the light emitted from the light-emitting element passes through the light combiner to form full-color image light.

24. The method of claim 22 or 23, wherein the light combiner comprises a planar optical element with a coating disposed at 45 ° and-45 ° to the two-color micro led and the single-color micro led, respectively.

25. The developing method according to claim 18, wherein the micro LED of the light emitting element connects P and N electrodes of a three-color LED with a circuit substrate in one manner selected from bonding and flip-chip.

26. The developing method according to claim 18, wherein the light-emitting element is selected from one of a uv LED and a blue LED coated with a nanomaterial phosphor to output full-color image light.

27. The developing method according to claim 18, wherein the micro led of the light emitting element outputs one selected from a group consisting of a monochrome image light, a two-color image light and a full-color image light.