CN109856897B

CN109856897B - Projection device

Info

Publication number: CN109856897B
Application number: CN201910199876.6A
Authority: CN
Inventors: 汤朝辉
Original assignee: Shenzhen Bojun Technology Development Co ltd
Current assignee: Shenzhen Bojun Technology Development Co ltd
Priority date: 2019-03-15
Filing date: 2019-03-15
Publication date: 2024-04-16
Anticipated expiration: 2039-03-15
Also published as: CN109856897A

Abstract

The invention is suitable for the technical field of projection, and provides a projection device which comprises a light source part and a liquid crystal chip part, wherein the light source part emits incident light comprising first band light, second band light and third band light and is incident on the liquid crystal chip part, the liquid crystal chip part respectively modulates the first band light, the second band light and the third band light in the first time period, the second time period and the third time period according to control signals so as to respectively generate three sub-pictures, and the three sub-pictures jointly correspond to the time of one frame of picture. According to the invention, three sub-pictures corresponding to the image picture are respectively obtained by modulating the liquid crystal chip part in extremely short time, the liquid crystal chip part can be arranged in a single piece by utilizing the visual persistence effect of human eyes, and a plurality of liquid crystal chips do not need to be arranged respectively corresponding to a plurality of color components of the video image, so that the invention not only has the advantages of high definition, bright color and the like of the 3LCD projection technology, but also can reduce the production cost and facilitate the popularization of the projection technology with ultra-high cost performance.

Description

Projection device

Technical Field

The present disclosure relates to projection technology, and particularly to a projection apparatus.

Background

Currently, the mainstream projection technologies include DLP (Digital Light Processing ), LCD (Liquid Crystal Display, liquid crystal display) and LCOS (Liquid Crystal on Silicon ), wherein the LCD projection is divided into two main streams, i.e. 3LCD projection and monolithic LCD projection.

In projector camping, the mainstream liquid crystal display projectors at present all use 3-piece HTPS (High Temperature Poly-Silicon, high temperature polysilicon) LCD liquid crystal panels, namely 3LCD. The 3LCD projector has superior color and the technical design is not separated. The three HTPS liquid crystal panels are respectively responsible for three components of red, green and blue of video signals, and the imaging and color reduction of the 3LCD technology is characterized in that three primary colors are fully and spatially mixed at the same time, and then images with different colors are projected, which is also called simultaneous spatial mixing reduction. Each HTPS liquid crystal panel of a 3LCD projector contains tens of thousands (even millions) of liquid crystals that can be configured to be in an on, off, or partially off state to allow light to pass through. In normal operation, each liquid crystal operates as a shutter. When the red, green and blue three colors penetrate different HTPS liquid crystal panels, the liquid crystal is instantly opened and closed based on the needed quantity of each color in the pixel point at the moment, so that the light ray is modulated, and an image projected on a screen is generated. From the actual experience of the user, the image of the 3LCD projector looks clearer, has fewer noise points and is more accurate in color reproduction.

The principle of a single-chip LCD projector is that the backlight part of an LCD panel is removed, then a high-power backlight source is used for irradiating the LCD panel through a condenser lens, and as the LCD panel is transparent, a picture is irradiated out and is imaged on a screen through a front focusing lens and a lens. The principle of the projector is very similar to that of a projector for teaching, the projector has the advantages of low price, low transmittance of a single LCD panel, bright color, few hundred lumens of brightness and difficulty in entering high-end business and household markets.

Therefore, it is desirable to provide a projection system that maintains the picture advantage of a 3LCD while also providing low cost.

Disclosure of Invention

The invention aims to provide a projection device and aims to solve the technical problem of high cost of a 3LCD projector.

The present invention is achieved by a projection apparatus comprising:

a light source section for emitting incident light including first band light, second band light, and third band light;

the liquid crystal chip part is used for respectively modulating the first band light, the second band light and the third band light in a first time period, a second time period and a third time period according to control signals so as to respectively generate a first sub-picture, a second sub-picture and a third sub-picture; the first sub-picture, the second sub-picture and the third sub-picture can correspondingly synthesize a frame of picture.

In one embodiment, the light source part includes a white light emitting assembly and a color separation assembly that allows a first band of light in white light emitted from the white light emitting assembly to pass in a first period of time, a second band of light in the white light to pass in a second period of time, and a third band of light in the white light to pass in a third period of time; the first band light, the second band light and the third band light are sequentially incident to the liquid crystal chip portion.

In one embodiment, the color separation assembly includes a first filter that allows the first band of light to pass, a second filter that allows the second band of light to pass, and a third filter that allows the third band of light to pass, the first, second, and third filters sequentially switching positions to pass the white light; or alternatively

The color separation assembly comprises a spectroscope element group and a time-sharing selection element, wherein the spectroscope element group is used for separating the first band light, the second band light and the third band light from the white light, the time-sharing selection element is arranged on sub-light paths of the first band light, the second band light and the third band light in a one-to-one correspondence mode, and the time-sharing selection element acts in the first time period, the second time period and the third time period sequentially.

In one embodiment, the light source part includes a first light emitting element for emitting the first band of light, a second light emitting element for emitting the second band of light, and a third light emitting element for emitting the third band of light; the first, second and third light emitting elements are turned on sequentially in the first, second and third time periods.

In one embodiment, the projection device further includes a polarization conversion section provided between the light source section and the liquid crystal chip section, the polarization conversion section converting the first band light, the second band light, and the third band light into polarized light of the same polarization direction; the liquid crystal chip part comprises a liquid crystal panel, an incident polarization element arranged on the light incident side of the liquid crystal panel and an emergent polarization element arranged on the light emergent side of the liquid crystal panel; the absorption axes of the incident polarizing element and the exit polarizing element are arranged parallel to each other and allow polarized light of the first, second, and third wavelength bands to pass.

In one embodiment, the incident polarizing element includes a first incident polarizer that allows the first band of light to pass therethrough, a second incident polarizer that allows the second band of light to pass therethrough, and a third incident polarizer that allows the third band of light to pass therethrough, the first, second, and third incident polarizers being sequentially switched into alignment with the liquid crystal panel during the first, second, and third time periods.

In one embodiment, the first, second and third incident polarizers are uniformly disposed on a turntable, and the first, second and third incident polarizers are sequentially aligned with the liquid crystal panel during rotation of the turntable.

In one embodiment, the first incident polarizer, the second incident polarizer and the third incident polarizer are disposed on an annular carrier, the liquid crystal panel is disposed inside the carrier, and the first incident polarizer, the second incident polarizer and the third incident polarizer are sequentially aligned with the liquid crystal panel during rolling of the carrier.

In one embodiment, the exit polarizing element includes a first exit polarizer that allows the first band of light to pass therethrough, a second exit polarizer that allows the second band of light to pass therethrough, and a third exit polarizer that allows the third band of light to pass therethrough, the first, second, and third exit polarizers being sequentially switched into alignment with the liquid crystal panel during the first, second, and third time periods.

In one embodiment, the projection device further includes a projection lens group disposed on the light emitting side of the liquid crystal chip portion, for projecting the first sub-frame, the second sub-frame, and the third sub-frame, respectively.

The single-chip LCD projection optical system provided by the embodiment of the invention comprises a light source part and a liquid crystal chip part, wherein the light source part can emit incident light comprising first band light, second band light and third band light, the incident light is incident on the liquid crystal chip part, the liquid crystal chip part respectively modulates the first band light, the second band light and the third band light in the first time period, the second time period and the third time period according to control signals, the incident light is modulated and emitted to respectively generate a first sub-picture, a second sub-picture and a third sub-picture, the first sub-picture, the second sub-picture and the third sub-picture correspond to the time of one frame picture together, the first sub-picture, the second sub-picture and the third sub-picture are respectively projected on a screen and enter human eyes in a very short time, the first sub-picture, the second sub-picture and the third sub-picture jointly synthesize one frame picture by utilizing the temporary effect of human eyes, the projection device decomposes images into three sub-pictures which are sequentially projected by utilizing the temporary effect, the liquid crystal chip part can be provided with a plurality of color components which are respectively corresponding to the single-chip LCD projection optical system, the LCD projection optical system has the advantages of high-quality, the LCD projection optical system has the advantages of being convenient and high-performance, and the projection cost is high, and the LCD projection optical system has the color ratio is more than 3, and has the color-saving the color and can be projected by the LCD projection optical system.

Drawings

FIG. 1 is a schematic diagram of a projection apparatus according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a projection apparatus according to an embodiment of the present invention;

FIG. 3 is a second light path diagram of the projection apparatus according to the embodiment of the present invention;

FIG. 4 is a third light path diagram of a projection apparatus according to an embodiment of the present invention;

FIG. 5 is a block diagram of a polarization conversion section of a projection apparatus according to an embodiment of the present invention;

FIG. 6 is an exploded view of a first embodiment of a switching assembly of a projection apparatus;

FIG. 7 is a first block diagram illustrating an assembly of a switching assembly of a projection apparatus according to an embodiment of the present invention;

FIG. 8 is a second block diagram of a switching assembly of a projection apparatus according to an embodiment of the present invention;

FIG. 9 is a third block diagram of a switching component of a projection apparatus according to an embodiment of the present invention;

FIG. 10 is an exploded view of a switching assembly of a projection device according to an embodiment of the present invention;

FIG. 11 is a diagram illustrating an assembly structure of a switching assembly of a projection apparatus according to an embodiment of the present invention;

FIG. 12 is a fifth block diagram of a switching assembly of a projection apparatus according to an embodiment of the present invention;

fig. 13 is a block diagram sixth of a switching assembly of a projection apparatus according to an embodiment of the present invention.

The meaning of the labels in the figures is:

100-projection means;

9-housing, 8-converging lens section, 70-control section, 75-lens section, 751-projection lens group;

1-a light source section, 11 '-white light emitting component, 12' -color separation component, 121-a first filter, 122-a second filter, 123-a third filter, 124-a spectroscope element group, 125-a time-sharing selection element, 13-a first light emitting element, 14-a second light emitting element, 15-a third light emitting element;

2-liquid crystal chip part, 20-liquid crystal panel, 21-incident polarizing element, 22-emergent polarizing element;

a 3-polarization conversion section, a prism 31, a polarization beam splitter film 32, a reflection film 33, a quarter wave plate 34;

40-turntables, 41-rotating shafts and 401-installation positions;

50-rolling elements, 51-carriers, 513-fixed positions, 511-first side, 512-second side;

61-first sub-picture, 62-second sub-picture, 63-third sub-picture.

Detailed Description

The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.

It will be understood that when an element is referred to as being "mounted" or "disposed" on another element, it can be directly or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly or indirectly connected to the other element. The terms "upper," "lower," "left," "right," and the like are used for convenience of description based on the orientation or positional relationship shown in the drawings, and do not denote or imply that the devices or elements being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the present patent. The terms "first," "second," and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features. The meaning of "a plurality of" is two or more, unless specifically defined otherwise.

In order to explain the technical scheme of the invention, the following is a detailed description with reference to the specific drawings and embodiments.

Referring to fig. 1 to 4, an embodiment of the present invention provides a projection apparatus 100, which includes a housing 9, a light source portion 1 and a liquid crystal chip portion 2 disposed in the housing 9, and a lens portion 75 disposed on the housing 9, wherein the light source portion 1 is configured to generate incident light, the incident light includes a first band light, a second band light and a third band light, the incident light is incident on the liquid crystal chip portion 2, the liquid crystal chip portion 2 modulates the first band light, the second band light and the third band light in a first period, a second period and a third period according to a control signal, respectively, and the incident light is emitted after being modulated by the liquid crystal chip portion 2 to generate a first sub-picture 61, a second sub-picture 62 and a third sub-picture 63, respectively, and finally is projected through the lens portion 75.

The projection device 100 provided by the embodiment of the invention comprises a shell 9, and a light source part 1 and a liquid crystal chip part 2 which are arranged in the shell 9, wherein the light source part 1 can emit incident light comprising first band light, second band light and third band light, the incident light is incident on the liquid crystal chip part 2, the liquid crystal chip part 2 respectively modulates the first band light, the second band light and the third band light in the first time period, the second time period and the third time period according to control signals, the incident light respectively generates a first sub-picture 61, a second sub-picture 62 and a third sub-picture 63 after being modulated and emitted, the first sub-picture 61, the second sub-picture 62 and the third sub-picture 63 jointly correspond to the time of one frame of picture, the first sub-picture 61, the second sub-picture 62 and the third sub-picture 63 are respectively projected onto the screen and enter human eyes in extremely short time, the first sub-picture 61, the second sub-picture 62 and the third sub-picture 63 jointly form a frame of picture by utilizing the visual persistence effect of human eyes, the projection device 100 decomposes the image picture into three sub-pictures projected in sequence by utilizing the visual persistence effect of human eyes, the liquid crystal chip part 2 can be arranged in a single chip mode, a plurality of liquid crystal chips do not need to be arranged respectively corresponding to a plurality of color components of the video image, the projection device not only has the advantages of high definition, bright color and the like of a 3LCD projection technology, but also reduces the production cost, and facilitates the popularization of the projection technology with ultra-high cost performance.

The first band light, the second band light, and the third band light are three components of white (W) light, and specifically, the description herein below will be made with the first band light being red (R) light, the second band light being green (G) light, and the third band light being blue (B) light. Of course, the first band light, the second band light, and the third band light are not limited to the order of the above three primary colors, and may be any order.

As shown in fig. 2, the sum of the first period (T1), the second period (T2), and the third period (T3) corresponds to a time (T) of one frame of a picture, also referred to as a frame interval time, t=1/F, where F is a frame rate of the current image signal. In a preferred implementation, t1=t2=t3=t/3, that is, the red light is emitted from the light source component and incident on the liquid crystal chip part 2 in the first 1/3 time of each frame to obtain a red sub-picture, the green light is emitted from the light source component and incident on the liquid crystal chip part 2 in the middle 1/3 time of each frame to obtain a green sub-picture, the blue light is emitted from the light source component and incident on the liquid crystal chip part 2 in the last 1/3 time of each frame to obtain a blue sub-picture, and the red sub-picture, the green sub-picture and the blue sub-picture respectively enter human eyes in the time of T/3, so that the red sub-picture, the green sub-picture and the blue sub-picture can synthesize pictures of corresponding frames due to the visual persistence effect of human eyes.

Here, the refresh frequency of the projection apparatus 100 is not limited, for example, there are 144Hz, 72Hz, and so on, and for the refresh frequency of 144Hz, the frame interval time t=1/144 s= 0.006944s, and then each of the three primary colors occupies 0.002315s.

Of course, referring to fig. 1, the projection apparatus 100 provided in the embodiment of the present invention further includes a control portion 70 disposed in the housing 9, wherein the control portion 70 is connected to the liquid crystal chip portion 2 for analyzing an input image signal, generating corresponding timing control signals, scanning signals and data signals according to the image signal, and providing the timing control signals, scanning signals and data signals to the liquid crystal chip portion 2 for respectively controlling transmission of red light, green light and blue light in different time periods of each frame.

Referring to fig. 1, in an embodiment, the projection apparatus 100 provided by the embodiment of the invention may further include a converging lens portion 8, where the converging lens portion 8 is disposed on an optical path between the light source portion 1 and the liquid crystal chip portion 2, and the converging lens portion 8 is configured to converge red light, green light and blue light from the light source portion 1, respectively, and the converged red light, green light and blue light are sequentially incident on the liquid crystal chip portion 2, so as to improve the light utilization rate of the light source portion 1. Referring to fig. 1, in an embodiment, a lens portion 5 of a projection apparatus 100 according to the present invention may include a projection lens group 51, where the projection lens group 51 is disposed on a light emitting side of a liquid crystal chip portion 2, and is configured to project a first sub-frame 61, a second sub-frame 62, and a third sub-frame 63 output from the liquid crystal chip portion 2 onto a projected surface such as a screen, a wall surface, etc.

As described below with reference to fig. 2 to 4, in the present embodiment, red light, green light, and blue light have sequentially appeared at a certain frequency and time period before reaching the liquid crystal chip portion 2. That is, the light source part 1 may emit red light, green light, and blue light, respectively, in the first, second, and third periods.

Referring to fig. 2 to 4, the light source portion 1 can control the emission of red light, green light and blue light in various manners, and specifically can directly emit red light, green light and blue light in sequence according to a predetermined frequency and a predetermined time period, or can sequentially intercept the red light, green light and blue light according to the predetermined frequency and the predetermined time period on the basis of emitting continuous and mixed light.

In some embodiments, as shown in fig. 2 and 3, the light source part 1 includes a white light emitting assembly 11, 11 'and a color separation assembly 12, 12', the white light emitting assembly 11, 11 'may emit white light, the color separation assembly 12, 12' allows red light in the white light to pass in a first period of time, allows green light in the white light to pass in a second period of time, and allows blue light in the white light to pass in a third period of time.

In this embodiment, the white Light Emitting components 11 and 11' may be any one of LEDs (Light-Emitting diodes), metal halogen lamps, ultra-high pressure mercury lamps, etc., which are capable of Emitting white Light, and are not limited herein in terms of specific choices of brightness requirements, cost, stability, etc.

In this embodiment, one implementation is that, as shown in fig. 2, the color separation assembly 12 includes a first filter 121, a second filter 122, and a third filter 123, the first filter 121 allowing red light to pass but not allowing green light and blue light to pass, the second filter 122 allowing green light to pass but not allowing red light and blue light to pass, the third filter 123 allowing blue light to pass but not allowing red light and green light to pass, the first filter 121 moving to the light path of white light in a first period of time to generate red light, the second filter 122 moving to the light path of white light in a first period of time to generate green light, and the third filter 123 moving to the light path of white light in a third period of time to generate blue light.

Preferably, the first filter 121, the second filter 122 and the third filter 123 respectively absorb light that is not allowed to pass through, so as to avoid interference to the screen caused by light that may be reflected or scattered and then enter the light path behind the color separation assembly 12.

Specifically, the first filter 121, the second filter 122, and the third filter 123 may be provided in the form of a color wheel, that is, disposed around the same center point and rotated, and the rotation speed of the color wheel is adapted to a required frame rate to generate red light, green light, and blue light corresponding to T/3 times, respectively, during the rotation.

Of course, the number of the first filter 121, the second filter 122, and the third filter 123 on the color wheel may be one or more. In the case of one group, the time for one rotation of the color wheel may be equal to the frame interval time, and in the case of multiple groups, the time for one rotation of the color wheel may be equal to the sum of the corresponding multiple frame intervals. The arrangement of the first filter 121, the second filter 122, and the third filter 123 on the color wheel is specifically performed as needed, and may not be limited thereto. In a specific application, the first filter 121, the second filter 122 and the third filter 123 may be in the form of respective filters, such as a red filter, a green filter and a blue filter, respectively.

In this embodiment, as shown in fig. 3, another implementation manner is that the color separation assembly 12' includes a dichroic mirror element group 124 (such as a dichroic prism group) and a time division selecting element 125, where the dichroic mirror separates the white light into red light, green light and blue light, and the red light, green light and blue light are respectively located on different sub-light paths, and are preferably arranged parallel to each other and at intervals. The three time-sharing selection elements 125 are arranged on the sub-optical path corresponding to the red light, the sub-optical path corresponding to the green light and the sub-optical path corresponding to the blue light in a one-to-one correspondence manner, and the three time-sharing selection elements 125 sequentially act in the time of the front T/3, the middle T/3 and the rear T/3 so as to respectively select the red light, the green light and the blue light corresponding to the time of the T/3.

In one particular application, time-sharing select element 125 may be a shutter. Of course, any element that can be opened or closed in a time-sharing manner can be applied thereto.

In another embodiment, as shown in fig. 4, the light source part 1 includes a first light emitting element 13 for emitting red light, a second light emitting element 14 for emitting green light, and a third light emitting element 15 for emitting blue light, and a light emission controller for controlling the first, second, and third light emitting elements 13, 14, and 15, the first, second, and third light emitting elements 13, 14, and 15 are turned on in sequence for a first, second, and third period of time according to a control signal of the light emission controller, so that red, green, and blue light corresponding to T/3 time, respectively, can be directly generated.

In this embodiment, the first light emitting element 13, the second light emitting element 14, and the third light emitting element 15 may each be an LED, and correspondingly, the first light emitting element 13 is a red LED, the second light emitting element 14 is a green LED, and the third light emitting element 15 is a blue LED.

Alternatively, in this embodiment, the first light emitting element 13, the second light emitting element 14, and the third light emitting element 15 may be a red laser light source, a green laser light source, and a blue laser light source, respectively.

Referring to fig. 2 to 4, the liquid crystal chip part 2 is used to modulate red light, green light, and blue light from the light source part 1.

Here, as shown in fig. 1 and fig. 5, the projection apparatus 100 provided in the embodiment of the present invention further includes a polarization conversion portion 3, where the polarization conversion portion 3 is disposed between the converging lens portion 8 and the liquid crystal chip portion 2, and is configured to convert all natural light from the light source portion 1 into polarized light with the same polarization direction, so as to be totally incident on the liquid crystal chip portion 2, thereby further improving the light utilization rate.

Specifically, as shown in fig. 5, there is provided a specific structure of a polarization conversion section 3, the polarization conversion section 3 includes two prisms 31, a polarization splitting film 32 is provided on a joint surface between the two prisms 31, a reflecting film 33 is further provided on an inclined surface of one of the prisms 31, and a quarter wave plate 34 is further provided on a light exit surface of the prism 31. The natural light is first reflected out of the S light after passing through the first prism 31, and the P light is converted into the S light after being reflected by the reflection film 33 and by the quarter wave plate 34, so that the natural light from the light source section 1 is all converted into polarized light of the same polarization direction. Of course, a small amount of P light may still be mixed in practice, but at least nearly half of the light is lost.

In other embodiments, the polarization conversion section 3 may be any other possible specific structure, and is not limited herein.

As shown in fig. 2 to 4, the liquid crystal chip section 2 includes an incident polarizing element 21, a liquid crystal panel 20, and an exit polarizing element 22, which are disposed in this order along the optical path direction. The incident polarizing element 21 and the exit polarizing element 22 each have an absorption axis and a transmission axis perpendicular to each other, and the incident polarizing element 21 and the exit polarizing element 22 are disposed parallel to each other, that is, the absorption axis of the incident polarizing element 21 and the absorption axis of the exit polarizing element 22 are disposed parallel to each other. The liquid crystal panel 20 includes a plurality of pixel points, a plurality of data lines and a plurality of scan lines, each pixel point is defined by one scan line crossing one data line, is controlled to be turned on or off by the scan line, is controlled to be applied with different pixel voltages by the data lines, and deflects liquid crystal molecules corresponding to each pixel point to different degrees under the action of the pixel voltages.

The incident polarizing element 21 and the exit polarizing element 22 are each disposed with their light transmission axes allowing S light to pass through. The incident polarizing element 21 further blocks a small amount of P light that is trapped, ensuring that the S light completely enters the liquid crystal panel 20. The S light enters each pixel point within the liquid crystal panel 20. The liquid crystal molecules corresponding to each pixel point on the liquid crystal panel 20 deflect correspondingly according to the applied data voltage so as to control the deflection degree of the incoming S light, the S light with different deflection degrees is incident on the emergent polarization element 22, further due to the selectivity of the transmission axis of the emergent polarization element 22, the S light which is not deflected can be totally emergent, and the S light which is partially deflected can be partially emergent, so that the corresponding light is emergent from the emergent polarization element 22 corresponding to each pixel point, a picture corresponding to a gray value is generated, and the picture surfaces of the pixels with different gray values form a sub-picture.

Thus, the red light, the green light and the blue light sequentially pass through the liquid crystal chip part 2, and a first sub-picture 61, a second sub-picture 62 and a third sub-picture 63 of one display picture, which correspond to the red component, the green component and the blue component respectively, can be obtained.

In some embodiments, the incident polarizing element 21 and the exit polarizing element 22 may be attached to the liquid crystal panel 20, fixed together, and fixed inside the case 9 at the same time. The incident polarizing element 21 and the exit polarizing element 22 allow S light of red light, green light, and blue light to pass therethrough at the same time. This way, the arrangement is simple and not easy to damage, and the cost of the projection device 100 according to the embodiment of the invention can be reduced.

In some embodiments, as shown in fig. 6 to 13, at most one of the incident polarizing element 21 and the exit polarizing element 22 is attached and fixed to the liquid crystal panel 20, but at least one of the following designs is selected.

Design one: the incident polarizing element 21 is designed according to wavelength characteristics of red light, green light, and blue light to achieve optimal absorption for unwanted light in the red light, green light, and blue light, respectively. Specifically, the incident polarizing element 21 includes a first incident polarizing plate, a second incident polarizing plate, and a third incident polarizing plate (not shown), and in particular, the first incident polarizing plate allows red light to pass therethrough and absorbs all other light than red light, and similarly, the second incident polarizing plate allows green light to pass therethrough and absorbs all other light than green light, and the third incident polarizing plate allows blue light to pass therethrough and absorbs all other light than blue light, to improve contrast of a picture. The first incident polaroid, the second incident polaroid and the third incident polaroid are sequentially switched to be aligned with the liquid crystal panel in the first time period, the second time period and the third time period, namely, the first incident polaroid, the second incident polaroid and the third incident polaroid are sequentially switched according to the light rays of the current required color.

Designing II: the exit polarizing element 22 is designed according to the wavelength characteristics of red, green and blue light to achieve optimal absorption for unwanted light in red, green and blue light, respectively. Specifically, the exit polarizer includes a first exit polarizer, a second exit polarizer, and a third exit polarizer (not shown), where the first exit polarizer allows red light to pass through and absorbs all other light except for red light, and the second exit polarizer allows green light to pass through and absorbs all other light except for green light, and the third exit polarizer allows blue light to pass through and absorbs all other light except for blue light, so as to improve contrast of the picture. The first outgoing polaroid, the second outgoing polaroid and the third outgoing polaroid are sequentially switched to be aligned with the liquid crystal panel in the first time period, the second time period and the third time period, namely, the first outgoing polaroid, the second outgoing polaroid and the third outgoing polaroid are sequentially switched according to the light rays of the current required color.

The incident polarizing element 21 and the exit polarizing element 22 may be formed as a single piece or may be formed as a combination of a plurality of pieces. Likewise, each of the first, second, and third incident polarizers in the incident polarizing element 21 may also be in a single-piece form or a multi-piece combination form, and each of the first, second, and third exit polarizers in the exit polarizing element 22 may also be in a single-piece form or a multi-piece combination form. This is chosen according to the specific needs and design to achieve an optimal balance between light efficiency and contrast.

In particular, switching of the entrance polarizing element and/or the exit polarizing element is achieved with a switching assembly.

As shown in fig. 6-9, the switching assembly is rotary, including a turntable 40. The corresponding sub-polarizers (first, second, third, first, second, and third) in the incident polarizing element 21 and/or the exit polarizing element 22 are uniformly arranged on the mounting locations 401 on the turntable 40, and during rotation of the turntable 40, the incident polarizing element 21 and/or the exit polarizing element 22 are sequentially aligned with the liquid crystal panel 20', and the rotation speed of the turntable 40 is adapted to the required frame rate to sequentially align the sub-polarizers in the incident polarizing element 21 and/or the exit polarizing element 22 with the liquid crystal panel 20' every T/3 time.

Specifically, the switching assembly further includes a rotating shaft 41, and the rotating disc 40 may be driven to rotate by the rotating shaft 41 connected to a central position of the rotating disc 40, as shown in fig. 6 to 9, and other realizations, such as a crankshaft connected to a non-central position of the rotating disc 40, are not described herein. Of course, the rotation of the turntable 40 is not exhaustive, and any method that can rotate the turntable 40 and align the required sub-polarizers with the liquid crystal panel 20' in turn can be used.

As shown in fig. 9, the turntable 40 may be a single layer, and disposed on the light emitting side of the exit polarizing element 22, and is suitable for the second design described above, where the first exit polarizing plate, the second exit polarizing plate, and the third exit polarizing plate are uniformly distributed on the turntable 40 and fixed on the mounting position 401;

alternatively, as shown in fig. 8, the turntable 40 is disposed on the light incident side of the incident polarizer 21, and the first incident polarizer, the second incident polarizer and the third incident polarizer are uniformly distributed on the turntable 40 and fixed on the mounting position 401;

alternatively, as shown in fig. 6 and 7, the rotating discs 40 are double-layered, and accordingly, a first incident polarizer, a second incident polarizer, and a third incident polarizer are disposed on the mounting position 401 of one rotating disc 40, and a first exit polarizer, a second exit polarizer, and a third exit polarizer are disposed on the mounting position 401 of the other rotating disc 40, and the liquid crystal panel 20' is disposed between the two rotating discs 40, and the two rotating discs 40 rotate synchronously, so that the first incident polarizer on the two rotating discs 40 is aligned with and synchronously switched with the first exit polarizer, the second incident polarizer is aligned with and synchronously switched with the second exit polarizer, and the third incident polarizer is aligned with and synchronously switched with the third exit polarizer, which is suitable for the above-mentioned case of simultaneous selection of the first and second designs.

As shown in fig. 10 to 13, the switching element is a scroll type. The entrance polarizing element 21 and/or the exit polarizing element 22 are brought into translation by means of a roller form. Specifically, the switching assembly includes an annular carrier 51 and a rolling member 50 driving the carrier 51 to roll.

As shown in fig. 10 to 13, the incident polarizing element 21 and/or the exit polarizing element 22 are sequentially arranged on the annular carrier 51, specifically, a plurality of fixing sites 513 are provided on the carrier 51. The rolling member 50 is engaged with the inner side surface of the carrier 51, and the liquid crystal panel 20 'is disposed inside the annular carrier 51, whereby the carrier 51 has a first side 511 and a second side 512 disposed corresponding to the light incident side and the light emergent side of the liquid crystal panel 20'.

In this case, as shown in fig. 12, the first incident polarizer, the second incident polarizer and the third incident polarizer may be sequentially disposed on the fixing portion 513 of the first side 511, and the second side 512 is correspondingly hollowed out or transparent, so that when the first incident polarizer, the second incident polarizer and the third incident polarizer on the first side 511 are aligned with the liquid crystal panel 20', the second side 512 does not affect the light emitted from the emitting polarizer 21, which is suitable for the first design;

as shown in fig. 13, the first exit polarizer, the second exit polarizer and the third exit polarizer may be sequentially disposed on the fixing portion 513 of the second side 512, where the first side 511 is disposed corresponding to the hollow or transparent manner, so that when the first exit polarizer, the second exit polarizer and the third exit polarizer on the second side 512 are aligned with the liquid crystal panel 20', the first side 511 does not affect the incidence of the light to the incident polarizer 21, which is suitable for the second design;

as shown in fig. 10 and 11, the first incident polarizer, the second incident polarizer and the third incident polarizer may be sequentially disposed on the fixed position 513 of the first side 511, and the first exit polarizer, the second exit polarizer and the third exit polarizer may be sequentially disposed on the fixed position 513 of the second side 512, and since the first side 511 and the second side 512 are reversely translated, the arrangement order of the first incident polarizer, the second incident polarizer and the third incident polarizer is opposite to the arrangement order of the first exit polarizer, the second exit polarizer and the third exit polarizer, which is suitable for the case of the above-mentioned design one and design two simultaneous choices.

Of course, the switching of the incident polarizing element 21 and/or the exit polarizing element 22 is not limited to the above-mentioned rotating disc form and drum form, and in other embodiments, the incident polarizing element 21 and/or the exit polarizing element 22 may be provided in a shutter form, and the corresponding sub-polarizers in the incident polarizing element 21 and/or the exit polarizing element 22 respectively act in the first time period, the second time period and the third time period to enable the S light of the red light, the green light and the blue light to pass through in sequence, and any manner that can be used for switching the sub-polarizers may be applied to this, which is not repeated.

The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention.

Claims

1. A projection apparatus, comprising:

a light source section for emitting incident light including first band light, second band light, and third band light; and

the liquid crystal chip part is used for respectively modulating the first band light, the second band light and the third band light in a first time period, a second time period and a third time period according to control signals so as to respectively generate a first sub-picture, a second sub-picture and a third sub-picture; the first sub-picture, the second sub-picture and the third sub-picture can correspondingly synthesize a frame of picture; the first time period, the second time period and the third time period are all one third of a frame interval time;

the projection device further comprises a polarization conversion part arranged between the light source part and the liquid crystal chip part, wherein the polarization conversion part converts the first wave band light, the second wave band light and the third wave band light into polarized light with the same polarization direction; the liquid crystal chip part comprises a liquid crystal panel, an incident polarization element arranged on the light incident side of the liquid crystal panel and an emergent polarization element arranged on the light emergent side of the liquid crystal panel; the absorption axes of the incident polarizing element and the emergent polarizing element are arranged in parallel to each other and allow the polarized light of the first, second and third wave bands to pass through;

the incident polarizing element includes a first incident polarizing plate allowing the first band of light to pass therethrough, a second incident polarizing plate allowing the second band of light to pass therethrough, and a third incident polarizing plate allowing the third band of light to pass therethrough, the first, second, and third incident polarizing plates being sequentially switched to be aligned with the liquid crystal panel in the first, second, and third time periods.

2. The projection device of claim 1, wherein the light source portion includes a white light emitting assembly and a color separation assembly that allows a first band of light in white light emitted by the white light emitting assembly to pass during a first period of time, a second band of light in the white light to pass during a second period of time, and a third band of light in the white light to pass during a third period of time; the first band light, the second band light and the third band light are sequentially incident to the liquid crystal chip portion.

3. The projection device of claim 2, wherein the color separation assembly includes a first filter that allows the first band of light to pass, a second filter that allows the second band of light to pass, and a third filter that allows the third band of light to pass, the first filter, second filter, and third filter sequentially switching positions to pass the white light; or alternatively

4. The projection apparatus according to claim 1, wherein the light source section includes a first light emitting element for emitting light of the first wavelength band, a second light emitting element for emitting light of the second wavelength band, and a third light emitting element for emitting light of a third wavelength band; the first, second and third light emitting elements are turned on sequentially in the first, second and third time periods.

5. The projection device of claim 1, wherein the first, second, and third incident polarizers are uniformly disposed on a rotating disk, and wherein the first, second, and third incident polarizers are sequentially aligned with the liquid crystal panel during rotation of the rotating disk.

6. The projection device of claim 1, wherein the first, second, and third incident polarizers are disposed on an annular carrier, the liquid crystal panel is disposed within the carrier, and the first, second, and third incident polarizers are sequentially aligned with the liquid crystal panel during rolling of the carrier.

7. The projection device of claim 1, wherein the exit polarizing element includes a first exit polarizer that allows the first band of light to pass therethrough, a second exit polarizer that allows the second band of light to pass therethrough, and a third exit polarizer that allows the third band of light to pass therethrough, the first, second, and third exit polarizers being sequentially switched into alignment with the liquid crystal panel during the first, second, and third time periods.

8. The projection device of any one of claims 1 to 7, further comprising a projection lens group disposed on a light-emitting side of the liquid crystal chip portion for projecting the first sub-picture, the second sub-picture, and the third sub-picture, respectively.