Patent Description:
The disclosure relates to an optical unit and an optical device, and more particularly to a display unit and a projection device provided with the display unit.

Generally speaking, a three-color-mixing projection device using digital light processing (DLP) and liquid crystal on silicone (LCoS) requires a solid-state light source such as light emitting diodes (LED) and laser diodes (LD) to provide illumination, and forms a projection beam in collaboration with an optical system design. However, the projection device formed in this way has a large size, which is not conducive to the manufacture of a small-size projection device.

There is an existing projection device formed by a display and a light combining system using multiple micro-LEDs as the light source, which has the advantage of small size. However, when the distance between micro-LEDs is less than <NUM> microns, a large number of micro-LED chips have to be transferred and bonded to the driving backboard, and in order to form a full-color panel, transfers of a large number of micro-LED chips have to be carried out for many times, and the processes are quite difficult. Therefore, currently, there is no one-piece full-color micro-LED display panel available on the market.

However, when a three-piece micro-LED display panel and an X prism light combining system are used to form a micro projection device, the beam provided by the micro-LEDs has a large light emitting angle, so the processing of light leakage of different colors of light and the alignment problem also becomes complicated. Even if a reflector or a micro lens array is used to reduce the light emitting angle of the beam provided by the micro-LEDs, when the distance between the micro-LEDs is less than <NUM> microns, the possible minimum of the light emitting half angle is about <NUM> degrees. Therefore, when light from different micro-LED display panels is combined, part of the beam is totally reflected in the X prism light combining system, which leads to the introduction of invalid light into the subsequent optical system and causes the generation of stray light, thus affecting the contrast of the image screen.

<CIT> relates to an image projection system configured to implement colour projection comprising: a first matrix device with an emissive display for transmitting a first and a second colour component of a colour image, wherein each pixel is adapted to transmit at the wavelengths associated with the first colour component and the wavelengths associated with the second colour component; and a second matrix device with an emissive display for transmitting a third colour component of the colour image.

The information disclosed in this Background section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Further, the information disclosed in the Background section does not mean that one or more problems to be resolved by one or more embodiments of the invention was acknowledged by a person of ordinary skill in the art.

The disclosure provides a display unit and a projection device, which have the advantages of small size and good image quality.

Other objects and advantages of the disclosure may be further understood from the technical features disclosed herein.

In order to achieve one or a part or all of the above or other objects, an embodiment of the disclosure provides a display unit. The display unit includes a first display panel, a wavelength conversion element, a second display panel, and a light combining element. The first display panel has multiple first light emitting elements which are configured to provide a first color light. The wavelength conversion element is located on a transmission path of the first color light and has a conversion region and a non-conversion region. A quantum dot conversion material is disposed on the conversion region. Part of the first color light is converted into a third color light after passing through the conversion region, and another part of the first color light passes through the non-conversion region. The second display panel has multiple second light emitting elements which are configured to provide a second color light. The light combining element is located on transmission paths of the first color light, the second color light and the third color light, and is configured to guide the third color light, the second color light and the first color light that passes through the non-conversion region to form an image beam.

In order to achieve one or a part or all of the above or other objects, an embodiment of the disclosure provides a projection device. The projection device includes the display unit and a projection lens. The projection lens is located on a transmission path of the image beam and is configured to project the image beam out of the projection device.

In another aspect a projection device is provided comprising: a display unit; and a projection lens, wherein the display unit is configured to provide an image beam and comprises:.

a first display panel; a wavelength conversion element; a second display panel; and a light combining element, wherein the first display panel has a plurality of first light emitting elements and the plurality of first light emitting elements are configured to provide a first color light, the wavelength conversion element is located on a transmission path of the first color light and has a conversion region and a non-conversion region, wherein a quantum dot conversion material is disposed on the conversion region, part of the first color light is converted into a third color light after passing through the conversion region, and another part of the first color light passes through the non-conversion region, the second display panel has a plurality of second light emitting elements and the plurality of second light emitting elements are configured to provide a second color light, and the light combining element is located on transmission paths of the first color light, the second color light and the third color light, wherein the third color light, the second color light and the first color light that passes through the non-conversion region are guided by the light combining element to form an image beam, and the projection lens is located on a transmission path of the image beam and is configured to project the image beam out of the projection device.

The aspects of the disclosure may be further embodied with one or more of the following optional features.

In or more embodiments, the first display panel may have a plurality of first pixel regions.

Each of the first light emitting elements may be disposed corresponding to each of the first pixel regions.

The non-conversion region may correspond to a first part of the first pixel regions.

The conversion region may correspond to a second part of the first pixel regions.

The number of the first part of the first pixel regions may be less than or equal to the number of the second part of the first pixel regions.

In or more embodiments, the display unit may further comprise a light concentrating element, disposed on transmission paths of the wavelength conversion element and the second color light and configured to make light emitting angles of the first color light.

The second color light and the third color light may be the same.

The light concentrating element may have a plurality of first concentrating units and a plurality of second concentrating units.

Each of the first concentrating units may be disposed corresponding to each of the first part of the first pixel regions.

Each of the second concentrating units may be disposed corresponding to each of the second part of the first pixel regions.

In or more embodiments, the second display panel may have a plurality of second pixel regions.

The light concentrating element may further comprise a plurality of third concentrating units.

Each of the third concentrating units may be disposed corresponding to each of the second pixel regions.

Each of the second light emitting elements may be disposed corresponding to each of the second pixel regions.

Each of the second pixel regions and each of the first pixel regions may have a one-to-many correspondence relationship.

The display unit may have a plurality of display pixel regions.

Each of the display pixel regions and each of the second pixel regions may have a one-to-one correspondence relationship.

Each of the second pixel regions and each of the first pixel regions may have a one-to-one correspondence relationship.

Each of the first pixel regions and each of the second pixel regions may have the same many-to-one correspondence relationship with each of the display pixel regions.

In or more embodiments, the first color light may be blue light, the second color light may be red light, and the third color light may be green light.

In or more embodiments, the first color light may be blue light, the second color light may be green light, and the third color light may be red light.

Based on the above, the embodiments of the disclosure have at least one of the following advantages or effects. In the embodiments of the disclosure, with the disposition of the first display panel and the second display panel of the display unit, it is not necessary to dispose an X prism light combining system, and it is possible to dispose only a single-piece beam splitter, which has advantages of a simple structure and small size, and may reduce the possibility of stray light due to introduction of invalid light into the subsequent optical system when the color light of different micro-LED display panels is totally reflected. Moreover, with the disposition of the first display panel and the second display panel of the display unit, the projection device has a simple structure, has the advantage of small size, may reduce the number of color lights that need to be aligned, and may also reduce the possibility of stray light in the system. In this way, the contrast and image quality of the image screen may be further enhanced.

Other objectives, features and advantages of the present invention will be further understood from the further technological features disclosed by the embodiments of the present invention wherein there are shown and described preferred embodiments of this invention, simply by way of illustration of modes best suited to carry out the invention.

In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings which form a part hereof, and in which are shown by way of illustration specific embodiments in which the invention may be practiced. In this regard, directional terminology, such as "top," "bottom," "front," "back," etc., is used with reference to the orientation of the Figure(s) being described. The components of the present invention can be positioned in a number of different orientations. As such, the directional terminology is used for purposes of illustration and is in no way limiting. On the other hand, the drawings are only schematic and the sizes of components may be exaggerated for clarity. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present invention. Also, it is to be understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. Unless limited otherwise, the terms "connected," "coupled," and "mounted" and variations thereof herein are used broadly and encompass direct and indirect connections, couplings, and mountings. Similarly, the terms "facing," "faces" and variations thereof herein are used broadly and encompass direct and indirect facing, and "adjacent to" and variations thereof herein are used broadly and encompass directly and indirectly "adjacent to". Therefore, the description of "A" component facing "B" component herein may contain the situations that "A" component directly faces "B" component or one or more additional components are between "A" component and "B" component. Also, the description of "A" component "adjacent to" "B" component herein may contain the situations that "A" component is directly "adjacent to" "B" component or one or more additional components are between "A" component and "B" component. Accordingly, the drawings and descriptions will be regarded as illustrative in nature and not as restrictive.

<FIG> is a schematic structural diagram of a projection device according to an embodiment of the disclosure. Please refer to <FIG>. A projection device <NUM> includes a display unit <NUM> and a projection lens <NUM>. The display unit <NUM> is configured to provide an image beam, and the projection lens <NUM> is located on a transmission path of the image beam and is configured to project the image beam out of the projection device <NUM>. For example, in this embodiment, the projection lens <NUM> includes, for example, a combination of one or more optical lenses with various diopter values, such as various combinations of non-planar lenses including, for example, biconcave lenses, biconvex lenses, concave-convex lenses, convex-concave lenses, plane-convex lenses, and plane-concave lenses. In an embodiment, the projection lens <NUM> may include planar optical lenses to project the image beam from the display unit <NUM> to a projection target, such as a screen or a wall, in a reflective or transmissive manner. The disclosure does not limit the form and type of the projection lens <NUM>.

In addition, as shown in <FIG>, in the embodiment, the display unit <NUM> includes a first display panel <NUM>, a wavelength conversion element <NUM>, a second display panel <NUM> and a light combining element <NUM>. Specifically, the first display panel <NUM> has multiple first light emitting elements <NUM> which may be configured to provide a first color light L1, and the second display panel <NUM> has multiple second light emitting elements <NUM> which may be configured to provide a second color light L2. For example, the first display panel <NUM> and the second display panel <NUM> are micro-LED display panels, and the first light emitting elements <NUM> and the second light emitting elements <NUM> may be blue micro-LEDs and red micro-LEDs, respectively, and may be configured to provide blue light and red light, respectively.

In addition, as shown in <FIG>, the wavelength conversion element <NUM> is located on the transmission path of the first color light L1 and is disposed between the light combining element <NUM> and the first display panel <NUM>. The wavelength conversion element <NUM> has a conversion region QR and a non-conversion region NR, and the conversion region QR is provided with a quantum dot conversion material QD, which may be configured to convert the first color light L1 into other colors. As shown in <FIG>, in the embodiment, part of the first color light L1 is converted into a third color light L3 after passing through the conversion region QR, and another part of the first color light L1 that passes through the non-conversion region NR not provided with the quantum dot conversion material QD is still the first color light L1 after passing through the non-conversion region NR. For example, in the embodiment, the quantum dot conversion material QD is a quantum dot conversion material QD that generates green light, and may convert blue light into green light. That is, in the embodiment, the first color light L1 is blue light, and the second color light L2 is red light, and the third color light L3 is green light.

Furthermore, the light combining element <NUM> is located on the transmission paths of the first color light L1, the second color light L2, and the third color light L3. The light combining element <NUM> may be a partially transmitting and partially reflecting element, a dichroic mirror, a polarization splitting element, or various other elements that may split beams. For example, in the embodiment, the light combining element <NUM> may reflect red light and allow blue light and green light to pass through. That is, the light combining element <NUM> may reflect the second color light L2 and allow the first color light L1 and the third color light L3 to pass through. In this way, the first color light L1 and the third color light L3 from the first display panel <NUM> may pass through the light combining element <NUM>, and the second color light L2 from the second display panel <NUM> may be reflected by the light combining element <NUM>, and under the guidance of the light combining element <NUM>, the first color light L1, the second color light L2, and the third color light L3 are mixed to form an image beam.

Moreover, as shown in <FIG>, in the embodiment, the projection lens <NUM> is placed on a side opposite to the first display panel <NUM>, so that the image beam may enter the projection lens <NUM>. Since the image beam is formed by the first color light L1, the second color light L2, and the third color light L3 of different colors, for the image beam, the color of the unit pixels of the display unit <NUM> may be adjusted by controlling the opening and closing of the unit pixels of the first display panel <NUM> and the second display panel <NUM>, so that the image screen formed by the image beam projected by the projection lens <NUM> may be a color screen.

In this way, with the disposition of the first display panel <NUM> and the second display panel <NUM> of the display unit <NUM>, it is not necessary to dispose an X prism light combining system, and it is possible to dispose only a single-piece beam splitter, which has advantages of a simple structure and small size, and may reduce the possibility of stray light due to introduction of invalid light into the subsequent optical system when the color light of different micro-LED display panels is totally reflected. Moreover, with the disposition of the first display panel <NUM> and the second display panel <NUM> of the display unit <NUM>, the projection device <NUM> has a simple structure, has the advantage of small size, may reduce the number of color lights that need to be aligned, and may also reduce the possibility of stray light in the system. In this way, the contrast and image quality of the image screen may be further enhanced.

Hereinafter, various correspondence relationships between the unit pixels of the display unit <NUM> and the unit pixels of the first display panel <NUM> and the second display panel <NUM> will be further described with reference to <FIG>.

<FIG> are diagrams showing various correspondence relationships between the unit pixels of the display unit of <FIG> and the unit pixels of the first display panel and the second display panel. In the embodiment, as shown in <FIG> to <FIG>, the first display panel <NUM> has multiple first pixel regions PX1. The first pixel regions PX1 are unit pixels of the first display panel <NUM>. Each first light emitting element <NUM> is respectively disposed on the first pixel region PX1. The non-conversion region NR corresponds to a first part PR1 of the first pixel regions PX1, and the conversion region QR corresponds to a second part PR2 of the first pixel regions PX1. In addition, the second display panel <NUM> has multiple second pixel regions PX2. The second pixel regions PX2 are unit pixels of the second display panel <NUM>, and each second light emitting element <NUM> is disposed corresponding to each second pixel region PX2.

Furthermore, in the embodiment, each second pixel region PX2 and each first pixel region PX1 may have a one-to-many correspondence relationship (as shown in <FIG>), or each second pixel region PX2 and each first pixel region PX1 may have a one-to-one correspondence relationship (as shown in <FIG>). For example, as shown in <FIG>, one second pixel region PX2 of the second display panel <NUM> corresponds to four first pixel regions PX1 of the first display panel <NUM>; that is, in the embodiment of <FIG>, the resolution of the first display panel <NUM> is greater than that of the second display panel <NUM>. In this way, the beam provided by the display pixel region of the display unit <NUM> as its unit pixel will be formed by the second color light L2 provided by one second pixel region PX2 of the second display panel <NUM> and the first color light L1 and the third color light L3 provided by four first pixel regions PX1 of the first display panel <NUM>. In this way, each display pixel region of the display unit <NUM> has a one-to-one correspondence relationship with each second pixel region PX2.

Moreover, in the embodiment, the number of the first part PR1 of the first pixel regions PX1 of the first display panel <NUM> is less than or equal to the number of the second part PR2 of the first pixel regions PX1 of the first display panel <NUM>. As shown in <FIG>, the ratio of the number of the first part PR1 of the first pixel regions PX1 to the number of the second part PR2 of the first pixel regions PX1 is <NUM>:<NUM>, or as shown in <FIG>, the ratio of the number of the first part PR1 of the first pixel regions PX1 to the number of the second part PR2 of the first pixel regions PX1 is <NUM>:<NUM>. In this way, the proportion of the first color light L1 of each display pixel region of the display unit <NUM> may be less than or equal to the proportion of the third color light L3. In addition, since the second pixel regions PX2 of the second display panel <NUM> is larger than the first pixel regions PX1 of the first display panel <NUM>, the proportion of the second color light L2 of each display pixel region of the display unit <NUM> is greater than the proportion of the first color light L1 or the third color light L3. In this way, in the embodiment, the proportion of red light in the white light formed by the display unit <NUM> is greater than the proportion of blue light or green light, which may enhance the red color performance of the projection screen of the projection device <NUM>, and may meet requirements of models of the projection device <NUM> with higher color performance requirements for the screen.

In addition, as shown in <FIG>, each second pixel region PX2 of the second display panel <NUM> corresponds to each first pixel region PX1 of the first display panel <NUM>, and they have a one-to-one correspondence relationship; that is, in the embodiments of <FIG>, the resolution of the first display panel <NUM> is equal to that of the second display panel <NUM>. However, in this way, the beam provided by the display pixel region of the display unit <NUM> as its unit pixel will be formed by the second color light L2 provided by four second pixel regions PX2 of the second display panel <NUM> and the first color light L1 and the third color light L3 provided by four first pixel regions PX1 of the first display panel <NUM>. In this way, each first pixel region PX1 and each second pixel region PX2 have the same many-to-one correspondence relationship with each display pixel region. In other words, the resolution of the display unit <NUM> is greater than the resolution of the first display panel <NUM> or the second display panel <NUM>.

Moreover, similar to the embodiment of <FIG>, in the embodiment of <FIG>, the number of the first part PR1 of the first pixel regions PX1 of the first display panel <NUM> is also less than or equal to the number of the second part PR2 of the first pixel regions PX1 of the first display panel <NUM>. In this way, the proportion of the second color light L2 of each display pixel region of the display unit <NUM> is also greater than the proportion of the first color light L <NUM> or the third color light L3. In this way, in the embodiment, the proportion of red light in the white light formed by the display unit <NUM> is greater than the proportion of blue light or green light, which may enhance the red color performance of the projection screen of the projection device <NUM>, and thus may meet requirements of models of the projection device <NUM> with higher color performance requirements for the screen.

In addition, please refer to <FIG>. In the embodiment, the display unit <NUM> may further include a light concentrating element <NUM>. The light concentrating element <NUM> is disposed on the transmission paths of the wavelength conversion element <NUM> and the second color light L2, and the light concentrating element <NUM> has multiple first concentrating units <NUM>, multiple second concentrating units <NUM>, and multiple third concentrating units <NUM>. For example, the light concentrating element <NUM> is an array lens; the first concentrating units <NUM>, the second concentrating units <NUM>, and the third concentrating units <NUM> are respectively different micro lens units, and their optically effective surfaces have different curvatures. Each of the first concentrating units <NUM> is disposed corresponding to each of the first part PR1 of the first pixel regions PX1, and each of the second concentrating units <NUM> is disposed corresponding to each of the second part PR2 of the first pixel regions PX1, and each of the third concentrating units <NUM> is disposed corresponding to each of the second pixel regions PX2. Thus, by the disposition of the first concentrating units <NUM>, the second concentrating units <NUM> and the third concentrating units <NUM>, the light emitting angles of the first color light L1, the second color light L2 and the third color light L3 may be further reduced, and the light emitting angles of the first color light L1, the second color light L2 and the third color light L3 may be made the same, which may further enhance the optical efficiency of the display unit <NUM>.

In addition, in the embodiment, the first color light L1 is blue light, and the second color light L2 is red light, and the third color light L3 is green light, but the disclosure is not limited thereto. In another embodiment, the first color light L1 may be blue light, and the second color light L2 may be green light, and the third color light L3 may be red light. In other words, the second light emitting elements <NUM> may be green micro-LEDs, and the quantum dot conversion material QD may be a quantum dot conversion material QD that generates red light. In this way, the color of the unit pixels of the display unit <NUM> may also be adjusted by controlling the opening and closing of the unit pixels of the first display panel <NUM> and the second display panel <NUM>, and the image screen projected by the projection lens <NUM> may also become a color screen. Moreover, in the embodiment, the proportion of green light in the white light formed by the display unit <NUM> is greater than the proportion of blue light or red light, and the proportion of red light is greater than or equal to the proportion of blue light, which may enhance the brightness of the projection screen of the projection device <NUM> without sacrificing the red color performance of the projection screen of the projection device <NUM>, and thus may meet requirements of models of the projection device <NUM> with higher brightness requirements for the screen.

<FIG> is a schematic structural diagram of a projection device according to another embodiment of the disclosure. Please refer to <FIG>. The display unit <NUM> of <FIG> is similar to the display unit <NUM> of <FIG>, and the differences are as follows. Specifically, as shown in <FIG>, in the embodiment, the light combining element <NUM> of the display unit <NUM> may reflect blue light and green light and allow red light to pass through, for example. That is, the light combining element <NUM> may reflect the first color light L1 and the third color light L3 and allow the second color light L2 to pass through to form an image beam. In addition, the projection lens <NUM> is placed on a side opposite to the second display panel <NUM>. In this way, the image beam may still enter the projection lens <NUM> after passing through the light combining element <NUM>. In the embodiment, the display unit <NUM> has a structure similar to that of the display unit <NUM>, and therefore, the projection device <NUM> may also achieve similar effects and advantages, which will not be repeated herein.

Claim 1:
A display unit comprising:
a first display panel (<NUM>) having a plurality of first light emitting elements (<NUM>), wherein the plurality of first light emitting elements (<NUM>) are configured to provide a first color light (L1);
a second display panel (<NUM>) having a plurality of second light emitting elements (<NUM>), wherein the plurality of second light emitting elements (<NUM>) are configured to provide a second color light (L2); and
a light combining element (<NUM>),
characterized in that the display unit further comprising:
a wavelength conversion element (<NUM>);
the wavelength conversion element (<NUM>) is located on a transmission path of the first color light (L1) and has a conversion region (QR) and a non-conversion region (NR), wherein a quantum dot conversion material (QD) is disposed on the conversion region (QR), part of the first color light (L1) is converted into a third color light (L3) after passing through the conversion region (QR), and another part of the first color light (L1) passes through the non-conversion region (NR); and
the light combining element (<NUM>) is located on transmission paths of the first color light (L1), the second color light (L2) and the third color light (L3), and is configured to guide the third color light (L3), the second color light (L2) and the first color light (L1) that passes through the non-conversion region (NR) to form an image beam.