CN114488666B

CN114488666B - Display unit and projection device

Info

Publication number: CN114488666B
Application number: CN202011268291.4A
Authority: CN
Inventors: 黄于铵; 庄福明
Original assignee: Coretronic Corp
Current assignee: Coretronic Corp
Priority date: 2020-11-13
Filing date: 2020-11-13
Publication date: 2023-06-06
Anticipated expiration: 2040-11-13
Also published as: CN114488666A

Abstract

A display unit and a projection apparatus are provided. The display unit comprises a first display panel, a wavelength conversion element, a second display panel and a light combining element. The first display panel is provided with a plurality of first light emitting elements for providing first color light. The wavelength conversion element is positioned on the transmission path of the first color light and provided with a conversion area and a non-conversion area, wherein the conversion area is provided with quantum dot conversion materials, part of the first color light passes through the conversion area and is converted into third color light, and the other part of the first color light penetrates through the non-conversion area. The second display panel is provided with a plurality of second light emitting elements for providing second color light. The light combining element is positioned on the transmission paths of the first color light, the second color light and the third color light and is used for forming an image light beam. The invention has the advantages of simple structure and small volume, and can reduce the possibility of parasitic light generation caused by the introduction of invalid light generated by the total reflection of the color light of different micro light emitting diode display panels into a subsequent optical system.

Description

Display unit and projection device

Technical Field

The present invention 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.

Background

Generally, a three-color light projection device employing digital light processing (Digital Light Processing, DLP) and reflective liquid crystal (Liquid Crystal On Silicone, LCoS) requires a solid-state light source such as a light-emitting diode (LED) and a laser diode (laser diode) to provide illumination, and is combined with an optical system design to form a projection beam. However, the projection device thus formed is bulky and disadvantageous for the fabrication of miniature projection devices.

There is a projector device formed by a display and a light combining system using a plurality of Micro light emitting diodes (Micro-LEDs) as light emitting sources, which has the advantage of small volume. However, when the spacing between the micro light emitting diodes is smaller than 5 μm, a large number of micro light emitting diode chips need to be transferred and bonded to the driving back plate, and if a full color panel is to be formed, a large number of micro light emitting diode chips need to be transferred multiple times, and the process is very difficult, so that no single-chip full color micro light emitting diode display panel is currently available on the market.

However, when the three-plate type micro light emitting diode display panel and the X-ray prism system are used to form the micro projection device, the light beam provided by the micro light emitting diode has a large light emitting angle, so that the light leakage of different colors and the alignment problem are complicated. Even if a reflective cover or a Micro Lens array (Micro Lens array) is used to reduce the light emission angle of the light beam provided by the Micro light emitting diodes, the minimum limit of the light emission half angle is about 20 degrees when the interval between the Micro light emitting diodes is smaller than 5 micrometers. Therefore, when light from different micro light emitting diode display panels is combined, partial light beams are totally reflected in the X-ray combining prism system, so that invalid light is led into a subsequent optical system to generate stray light, and the contrast of an image picture is affected.

The background section is only for the purpose of aiding in the understanding of the present invention and thus the disclosure of the background section may include some techniques that do not form part of the knowledge of one of ordinary skill in the art. The disclosure of the "background" section is not intended to represent the subject matter or problem underlying one or more embodiments of the present invention, as it would be known or appreciated by one of ordinary skill in the art prior to the application of the present invention.

Disclosure of Invention

The invention provides a display unit and a projection device, which have the advantages of small volume and good picture quality.

Other objects and advantages of the present invention will be further appreciated from the technical features disclosed in the present invention.

To achieve one or a part or all of the above or other objects, an embodiment of the present invention provides a display unit. The display unit comprises a first display panel, a wavelength conversion element, a second display panel and a light combining element. The first display panel is provided with a plurality of first light-emitting elements, wherein the first light-emitting elements are used for providing first color light. The wavelength conversion element is positioned on the transmission path of the first color light and provided with a conversion area and a non-conversion area, wherein the conversion area is provided with quantum dot conversion materials, part of the first color light passes through the conversion area and is converted into third color light, and the other part of the first color light penetrates through the non-conversion area. The second display panel is provided with a plurality of second light-emitting elements, wherein the second light-emitting elements are used for providing second color light. The light combining element is located on the transmission paths of the first color light, the second color light and the third color light and used for guiding the third color light, the second color light and the first color light penetrating through the non-conversion area to form an image light beam.

To achieve one or a part or all of the above or other objects, an embodiment of the present invention provides a projection apparatus. The projection device comprises a display unit and a projection lens. The projection lens is positioned on the transmission path of the image light beam and is used for projecting the image light beam out of the projection device.

Based on the foregoing, embodiments of the present invention have at least one of the following advantages or effects. In the embodiment of the invention, through the configuration of the first display panel and the second display panel of the display unit, an X-prism light combining system is not required to be configured, and only a single-piece type spectroscope is configured, so that the embodiment has the advantages of simple structure and small volume, and the possibility of parasitic light caused by invalid light introduced into a subsequent optical system when the color light of different micro light emitting diode display panels is totally reflected can be reduced. In addition, the configuration of the first display panel and the second display panel of the display unit is adopted, so that the projection device has the advantages of simple structure and small volume, the quantity of colored light needing to be aligned can be reduced, and the possibility of generating system parasitic light can be reduced. Thus, the contrast ratio and the image quality of the image picture can be further improved.

In order to make the above features and advantages of the present invention more comprehensible, embodiments accompanied with figures are described in detail below.

Drawings

Fig. 1 is a schematic diagram of a projection apparatus according to an embodiment of the invention.

Fig. 2A to 2D are various corresponding diagrams of unit pixels of the display unit of fig. 1 and unit pixels of the first display panel and the second display panel.

Fig. 3 is a schematic diagram of a projection apparatus according to another embodiment of the invention.

Detailed Description

The foregoing and other features, aspects and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiment, which proceeds with reference to the accompanying drawings. The directional terms mentioned in the following embodiments are, for example: upper, lower, left, right, front or rear, etc., are merely references to the directions of the drawings. Thus, the directional terminology is used for purposes of illustration and is not intended to be limiting of the invention.

Fig. 1 is a schematic diagram of a projection apparatus according to an embodiment of the invention. Referring to fig. 1, a projection apparatus 200 includes a display unit 100 and a projection lens 210. The display unit 100 is used for providing an image beam, and the projection lens 210 is located on a transmission path of the image beam and is used for projecting the image beam out of the projection device 200. For example, in the present embodiment, the projection lens 210 includes, for example, a combination of one or more optical lenses having diopters, such as various combinations of non-planar lenses including biconcave lenses, biconvex lenses, meniscus lenses, convex-concave lenses, plano-convex lenses, and plano-concave lenses. In an embodiment, the projection lens 210 may also include a planar optical lens to reflect or penetrate the image beam from the display unit 100 to a projection target, such as a screen or a wall. The type and kind of the projection lens 210 are not limited in the present invention.

On the other hand, as shown in fig. 1, in the present embodiment, the display unit 100 includes a first display panel 110, a wavelength conversion element 120, a second display panel 130, and a light combining element 140. Specifically, the first display panel 110 has a plurality of first light emitting elements 111 for providing the first color light L1, and the second display panel 130 has a plurality of second light emitting elements 131 for providing the second color light L2. For example, the first display panel 110 and the second display panel 130 are micro light emitting diode display panels, and the first light emitting element 111 and the second light emitting element 131 can be blue micro light emitting diodes and red micro light emitting diodes, respectively, and can be used for providing blue light and red light, respectively.

On the other hand, as shown in fig. 1, the wavelength conversion element 120 is disposed on the transmission path of the first color light L1 and between the light combining element 140 and the first display panel 110, and the wavelength conversion element 120 has a conversion region QR and a non-conversion region NR, wherein the conversion region QR is provided with quantum dot conversion materials QD for converting the first color light L1 into other color light. As shown in fig. 1, in the present embodiment, a part of the first color light L1 is converted into the third color light L3 after passing through the conversion region QR, and another part of the first color light L1 is still the first color light L1 after passing through the non-conversion region NR without the quantum dot conversion material QD. For example, in the present embodiment, the quantum dot conversion material QD is a quantum dot conversion material QD generating green light, and blue light can be converted into green light. That is, in the present embodiment, the first color light L1 is blue light, the second color light L2 is red light, and the third color light L3 is green light.

Further, the light combining element 140 is located on the transmission path of the first color light L1, the second color light L2 and the third color light L3. The light combining element 140 may be a partially transmissive partially reflective element, a dichroic element (dichroic mirror), a polarizing element, or various other elements that split the light beam. For example, in the present embodiment, the light combining element 140 can reflect red light and transmit blue light and green light, for example. That is, the light combining element 140 can reflect the second color light L2 and transmit the first color light L1 and the third color light L3. Thus, the first color light L1 and the third color light L3 from the first display panel 110 can penetrate the light combining element 140, and the second color light L2 from the second display panel 130 can be reflected by the light combining element 140, and the first color light L1, the second color light L2 and the third color light L3 are mixed to form an image beam by guiding the light combining element 140.

In addition, as shown in fig. 1, in the present embodiment, the projection lens 210 is disposed at a side opposite to the first display panel 110, so that the image beam can enter the projection lens 210. Since the image light beams are formed by the first color light L1, the second color light L2 and the third color light L3 with different colors, the image light beams can adjust the colors of the unit pixels of the display unit 100 by controlling the on and off of the unit pixels of the first display panel 110 and the second display panel 130, so that the image picture formed by the image light beams projected by the projection lens 210 can be a color picture.

Therefore, through the configuration of the first display panel 110 and the second display panel 130 of the display unit 100, the X-prism light combining system is not required, but only a single-chip beam splitter is configured, so that the display unit has the advantages of simple structure and small volume, and the possibility of parasitic light generated by introducing invalid light generated when the color light of different micro light emitting diode display panels is totally reflected into a subsequent optical system can be reduced. In addition, the configuration of the first display panel 110 and the second display panel 130 of the display unit 100 simplifies the structure of the projection device 200, has the advantage of small volume, reduces the number of colored lights required for alignment, and reduces the possibility of generating system parasitic lights. Thus, the contrast ratio and the image quality of the image picture can be further improved.

Various corresponding relationships between the unit pixels of the display unit 100 and the unit pixels of the first display panel 110 and the second display panel 130 will be further described below with reference to fig. 2A to 2D.

Fig. 2A to 2D are various corresponding diagrams of unit pixels of the display unit of fig. 1 and unit pixels of the first display panel and the second display panel. In the present embodiment, as shown in fig. 1 and 2A to 2D, the first display panel 110 has a plurality of first pixel areas PX1, the first pixel areas PX1 are unit pixels of the first display panel 110, each of the first light emitting elements 111 is disposed on the first pixel areas PX1, the non-conversion areas NR correspond to the first portions PR1 of the first pixel areas PX1, and the conversion areas QR correspond to the second portions PR2 of the first pixel areas PX 1. On the other hand, the second display panel 130 has a plurality of second pixel areas PX2, and the second pixel areas PX2 are unit pixels of the second display panel 130, and each of the second light emitting elements 131 is provided corresponding to each of the second pixel areas PX 2.

In the present embodiment, each second pixel area PX2 and each first pixel area PX1 may have a one-to-many correspondence (as shown in fig. 2A and 2B), or each second pixel area PX2 and each first pixel area PX1 may have a one-to-one correspondence (as shown in fig. 2C and 2D). For example, as shown in fig. 2A and 2B, one second pixel area PX2 of the second display panel 130 corresponds to four first pixel areas PX1 of the first display panel 110, that is, in the embodiment of fig. 2A and 2B, the resolution of the first display panel 110 is greater than that of the second display panel 130. In this way, the light beam provided by the display pixel area of the unit pixel of the display unit 100 is formed by the second color light L2 provided by the second pixel area PX2 of the second display panel 130 and the first color light L1 and the third color light L3 provided by the four first pixel areas PX1 of the first display panel 110, and thus, each display pixel area of the display unit 100 has a one-to-one correspondence with each second pixel area PX 2.

In the present embodiment, the number of the first portions PR1 of the first pixel area PX1 of the first display panel 110 is equal to or less than the number of the second portions PR2 of the first pixel area PX1 of the first display panel 110. As shown in fig. 2A, the ratio of the number of the first portions PR1 of the first pixel area PX1 to the number of the second portions PR2 of the first pixel area PX1 is 1 to 1, or as shown in fig. 2B, the ratio of the number of the first portions PR1 of the first pixel area PX1 to the number of the second portions PR2 of the first pixel area PX1 is 1 to 3. In this way, the proportion of the first color light L1 in each display pixel area of the display unit 100 may be less than or equal to the proportion of the third color light L3. On the other hand, since the second pixel area PX2 of the second display panel 130 is larger than the first pixel area PX1 of the first display panel 110, the proportion of the second color light L2 of each display pixel area of the display unit 100 is larger than the proportion of the first color light L1 or the third color light L3. Thus, in the present embodiment, the proportion of red light in the white light formed by the display unit 100 is greater than the proportion of blue light or green light, so that the red color performance of the projection screen of the projection device 200 can be improved, and the model of the projection device 200 with high requirements on the color performance of the screen can be satisfied.

On the other hand, as shown in fig. 2C and 2D, each second pixel area PX2 of the second display panel 130 corresponds to each first pixel area PX1 of the first display panel 110 to have a one-to-one correspondence, that is, in the embodiment of fig. 2A and 2B, the resolution of the first display panel 110 is equal to the second display panel 130. However, in this way, the light beams provided by the display pixel areas of the unit pixels of the display unit 100 are formed by the second color light L2 provided by the four second pixel areas PX2 of the second display panel 130 and the first color light L1 and the third color light L3 provided by the four first pixel areas PX1 of the first display panel 110, so that each of the first pixel areas PX1 and each of the second pixel areas PX2 have the same many-to-one correspondence relationship with each of the display pixel areas, that is, the resolution of the display unit 100 is greater than the resolution of the first display panel 110 or the second display panel 130.

Also, similar to the embodiment of fig. 2A and 2B, in the embodiment of fig. 2C and 2D, the number of the first portions PR1 of the first pixel areas PX1 of the first display panel 110 is also less than or equal to the number of the second portions PR2 of the first pixel areas PX1 of the first display panel 110. Thus, the proportion of the second color light L2 in each display pixel area of the display unit 100 is also greater than the proportion of the first color light L1 or the third color light L3. Thus, in the present embodiment, the proportion of red light in the white light formed by the display unit 100 is greater than the proportion of blue light or green light, so that the red color performance of the projection screen of the projection device 200 can be improved, and the model of the projection device 200 with high requirements on the color performance of the screen can be satisfied.

In addition, referring to fig. 1 and 2A, in the present embodiment, the display unit 100 may further include a light concentrating element 150. The light concentrating element 150 is disposed on the transmission path of the wavelength conversion element 120 and the second color light L2, wherein the light concentrating element 150 has a plurality of first concentrating units 151, a plurality of second concentrating units 152, and a plurality of third concentrating units 153. For example, the light concentrating element 150 is an array lens, the first concentrating unit 151, the second concentrating units 152 and the third concentrating units 153 are respectively different microlens units, and the optically effective surfaces thereof have different curvatures. The first concentrating units 151 are disposed corresponding to the first portions PR1 of the first pixel areas PX1, the second concentrating units 152 are disposed corresponding to the second portions PR2 of the first pixel areas PX1, and the third concentrating units 153 are disposed corresponding to the second pixel areas PX2, so that the light emission angles of the first color light L1, the second color light L2, and the third color light L3 can be further reduced and the light emission angles of the first color light L1, the second color light L2, and the third color light L3 can be the same by the arrangement of the first concentrating units 151, the second concentrating units 152, and the third concentrating units 153, and the optical efficiency of the display unit 100 can be further improved.

In addition, it is noted that in the present embodiment, the first color light L1 is blue light, the second color light L2 is red light, and the third color light L3 is green light, but the present invention is not limited thereto. In another embodiment, the first color light L1 is blue light, the second color light L2 is green light, and the third color light L3 is red light. That is, the second light emitting element 131 may be a green micro light emitting diode, and the quantum dot conversion material QD may be a quantum dot conversion material QD generating red light. In this way, the color of the unit pixels of the display unit 100 can be adjusted by controlling the on/off of the unit pixels of the first display panel 110 and the second display panel 130, and the image projected by the projection lens 210 can be a color image. In this embodiment, the proportion of green light in the white light formed by the display unit 100 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, so that the brightness of the projection screen of the projection device 200 can be improved, and the red color representation of the projection screen of the projection device 200 can be considered, so that the machine type of the projection device 200 with higher requirements on the brightness of the screen can be satisfied.

Fig. 3 is a schematic diagram of a projection apparatus according to another embodiment of the invention. Referring to fig. 3, the display unit 300 of fig. 3 is similar to the display unit 100 of fig. 1, with the following differences. Specifically, as shown in fig. 3, in the present embodiment, the light combining element 340 of the display unit 300 can reflect blue light and green light, for example, and allow the red light to penetrate. That is, the light combining element 340 can reflect the first color light L1 and the third color light L3 and transmit the second color light L2 to form an image beam. The projection lens 210 is disposed on a side opposite to the second display panel 130. Thus, the image beam can still enter the projection lens 210 after passing through the light combining element 340. In this embodiment, the display unit 300 and the display unit 100 have similar structures, so that the projection device 200 can achieve similar effects and advantages, and will not be described herein.

In summary, the embodiments of the present invention have at least one of the following advantages or effects. In the embodiment of the invention, through the configuration of the first display panel and the second display panel of the display unit, an X-prism light combining system is not required to be configured, and only a single-piece type spectroscope is configured, so that the embodiment has the advantages of simple structure and small volume, and the possibility of parasitic light generation caused by the introduction of invalid light generated when the color light of different micro light emitting diode display panels is totally reflected into a subsequent optical system can be reduced. In addition, the configuration of the first display panel and the second display panel of the display unit is adopted, so that the projection device has the advantages of simple structure and small volume, the quantity of colored light needing to be aligned can be reduced, and the possibility of generating system parasitic light can be reduced. Thus, the contrast ratio and the image quality of the image picture can be further improved.

However, the foregoing is only illustrative of the preferred embodiments of the present invention and is not to be construed as limiting the scope of the invention, which is defined by the appended claims and their equivalents as filed in light of the foregoing disclosure. Not all of the objects, advantages, or features of the present disclosure are required to be achieved by any one embodiment or claim of the present disclosure. Furthermore, the abstract and the title of the invention are provided solely for the purpose of assisting patent document retrieval and are not intended to limit the scope of the claims. Furthermore, references to "first," "second," etc. in this specification or in the claims are only intended to name an element or distinguish between different embodiments or ranges, and are not intended to limit the upper or lower limit on the number of elements.

Reference numerals illustrate:

100. 300: display unit

110: first display panel

111: first light-emitting element

120: wavelength conversion element

130: second display panel

131: second light-emitting element

140. 340: light combining element

150: light concentrating element

151: first concentrating unit

152: second concentrating unit

153: third concentrating unit

200: projection device

210: projection lens

L1: first color light

L2: second color light

L3: third color light

NR: non-conversion region

PR1: first part

PR2: second part

PX1: a first pixel region

PX2: a second pixel region

QD: quantum dot conversion material

QR (quick response): and (5) converting the area.

Claims

1. A display unit comprising a first display panel, a wavelength conversion element, a second display panel, and a color separation element, wherein:

the first display panel is provided with a plurality of first light-emitting elements, wherein the plurality of first light-emitting elements are used for providing first color light;

the wavelength conversion element is positioned on the transmission path of the first color light and provided with a conversion area and a non-conversion area, wherein a quantum dot conversion material is arranged on the conversion area, part of the first color light is converted into third color light after passing through the conversion area, and the other part of the first color light penetrates through the non-conversion area;

the second display panel is provided with a plurality of second light-emitting elements, wherein the plurality of second light-emitting elements are used for providing second color light; and

the color separation element is located on the transmission paths of the first color light, the second color light and the third color light, and is used for guiding the third color light, the second color light and the first color light penetrating through the non-conversion area to form an image beam.

2. The display unit according to claim 1, wherein the first display panel has a plurality of first pixel regions, each of the first light emitting elements is provided corresponding to each of the first pixel regions, the non-conversion region corresponds to a first portion of the plurality of first pixel regions, the conversion region corresponds to a second portion of the plurality of first pixel regions, and the number of the first portions of the plurality of first pixel regions is equal to or less than the number of the second portions of the plurality of first pixel regions.

3. The display unit of claim 2, further comprising:

and a light concentrating element disposed on the transmission paths of the wavelength conversion element and the second color light for making the light emission angles of the first color light, the second color light, and the third color light the same, wherein the light concentrating element has a plurality of first concentrating units and a plurality of second concentrating units, each of the first concentrating units is disposed corresponding to each of the first portions of the plurality of first pixel regions, and each of the second concentrating units is disposed corresponding to each of the second portions of the plurality of first pixel regions.

4. The display unit according to claim 3, wherein the second display panel has a plurality of second pixel regions, the light concentrating element further includes a plurality of third concentrating units, each of the third concentrating units is provided corresponding to each of the plurality of second pixel regions, each of the second light emitting elements is provided corresponding to each of the second pixel regions, each of the second pixel regions has a one-to-many correspondence with each of the first pixel regions, and the display unit has a plurality of display pixel regions, each of the display pixel regions has a one-to-one correspondence with each of the second pixel regions.

5. The display unit according to claim 2, wherein the second display panel has a plurality of second pixel regions, each of the second light emitting elements is provided corresponding to each of the second pixel regions, each of the second pixel regions has a one-to-one correspondence with each of the first pixel regions, and the display unit has a plurality of display pixel regions, each of the first pixel regions and each of the second pixel regions has the same many-to-one correspondence with each of the display pixel regions.

6. The display unit of claim 1, wherein the first color light is blue light, the second color light is red light, and the third color light is green light.

7. The display unit of claim 1, wherein the first color light is blue light, the second color light is green light, and the third color light is red light.

8. A projection device, comprising a display unit and a projection lens, wherein:

the display unit is used for providing image light beams and comprises a first display panel, a wavelength conversion element, a second display panel and a color separation element, wherein:

the wavelength conversion element is positioned on the transmission path of the first color light and provided with a conversion area and a non-conversion area, wherein quantum dot conversion materials are arranged on the conversion area, part of the first color light passes through the conversion area and is converted into third color light, and the other part of the first color light penetrates through the non-conversion area;

the color separation element is positioned on the 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 penetrating through the non-conversion area are guided by the color separation element to form the image light beam; and

the projection lens is positioned on the transmission path of the image light beam and is used for projecting the image light beam out of the projection device.

9. The projection device of claim 8, wherein the first display panel has a plurality of first pixel regions, each of the first light emitting elements is disposed corresponding to each of the first pixel regions, the non-conversion region corresponds to a first portion of the plurality of first pixel regions, the conversion region corresponds to a second portion of the plurality of first pixel regions, and a number of the first portion of the plurality of first pixel regions is equal to or less than a number of the second portion of the plurality of first pixel regions.

10. The projection device of claim 9, wherein the display unit further comprises:

11. The projection apparatus according to claim 10, wherein the second display panel has a plurality of second pixel regions, the light concentrating element further includes a plurality of third concentrating units, each of the third concentrating units is provided corresponding to each of the plurality of second pixel regions, each of the second light emitting elements is provided corresponding to each of the second pixel regions, each of the second pixel regions has a one-to-many correspondence with each of the first pixel regions, and the display unit has a plurality of display pixel regions, each of the display pixel regions has a one-to-one correspondence with each of the second pixel regions.

12. The projection device of claim 9, wherein the second display panel has a plurality of second pixel regions, each of the second light emitting elements is disposed corresponding to each of the second pixel regions, each of the second pixel regions has a one-to-one correspondence with each of the first pixel regions, and the display unit has a plurality of display pixel regions, each of the first pixel regions and each of the second pixel regions has a same many-to-one correspondence with each of the display pixel regions.

13. The projection device of claim 8, wherein the first color light is blue light, the second color light is red light, and the third color light is green light.

14. The projection device of claim 8, wherein the first color light is blue light, the second color light is green light, and the third color light is red light.