CN116256916A

CN116256916A - Optical machine, display device and vehicle

Info

Publication number: CN116256916A
Application number: CN202310313287.2A
Authority: CN
Inventors: 李志纲; 邓远博
Original assignee: Nanjing Ruiweishi Technology Co ltd
Current assignee: Nanjing Ruiweishi Technology Co ltd
Priority date: 2023-03-28
Filing date: 2023-03-28
Publication date: 2023-06-13

Abstract

The application relates to the technical field of projection display, in particular to a light machine, display equipment and a vehicle. According to the light source, the quarter wave plate capable of changing the polarization characteristic of the P polarized light is arranged between the backlight source and the image source, the reflection type polaroid and the reflection unit for realizing light path planning are arranged in a matched mode, the illumination light converts the P polarized light into the S polarized light after passing through the quarter wave plate twice by the reflection type polaroid, and then the converted S polarized light is provided for the image source through the reflection unit, so that the brightness of the image source is improved. The utility model discloses can improve the light utilization efficiency of ray apparatus inside, reduce the consumption of backlight when satisfying luminance, and then reduce the illumination light projection and generate heat the temperature rise that arouses on the image source.

Description

Optical machine, display device and vehicle

Technical Field

The application relates to the technical field of projection display, in particular to a light machine, display equipment and a vehicle.

Background

The HUD (Head Up Display) is an entirely new way of realizing a Display by reflection on a transparent surface (e.g. a vehicle windshield), which in particular emits Display light by the light engine of the HUD Display device and projects on the transparent surface through corresponding optical lenses. However, before the backlight source in the optical machine provides the illumination light to the image source, energy is lost due to multiple reflection or polarization cut-off, so that the light utilization efficiency is low. Therefore, if the HUD display device needs to emit enough high brightness of the display light, the illumination light emitted by the backlight source needs to have higher brightness, and a large amount of heat is generated, which stresses the heat dissipation of the whole system.

Disclosure of Invention

An object of the application is to provide an optical machine, display device and vehicle, solved among the prior art inside illumination light utilization efficiency of optical machine not high, the luminance loss that the backlight provided seriously arouses the technical problem of temperature rise.

In order to solve the technical problems, the application adopts the following technical scheme:

in a first aspect, the present application provides an optical engine comprising:

the backlight source provides illumination light for the image source;

the illumination light reaches the image source from the backlight source, a quarter wave plate and a reflective polarizer are sequentially arranged on the light path of the illumination light, and P polarized light in the illumination light is converted into S polarized light through at least twice passing through the quarter wave plate by reflection of the reflective polarizer;

and the reflection unit is matched with the reflection type polaroid and is at least used for reflecting the converted S-polarized light to the image source.

In an optional implementation manner of the first aspect, the reflecting unit is at least configured to reflect the converted S-polarized light onto the image source, and includes:

and the converted S polarized light passes through the quarter wave plate and the reflective polarizer and then reaches the image source.

In an alternative implementation manner of the first aspect, the S polarized light in the illumination light is directly projected onto the image source through the transmission of the quarter-wave plate and the reflective polarizer.

In an optional implementation manner of the first aspect, the reflection unit is disposed on a back plate corresponding to the backlight, and is located in a gap between the light emitters.

In an optional implementation manner of the first aspect, the reflecting unit is a mirror disposed between the backlight and the quarter wave plate, and the reflecting unit is further configured to reflect the illumination light emitted by the backlight onto the quarter wave plate.

In an alternative embodiment of the first aspect, the reflecting unit is provided with a first adjusting structure for adjusting the reflecting angle of the illumination light.

In an alternative embodiment of the first aspect, the reflective polarizer is provided with a second adjustment structure to adjust the reflection path of the P-polarized light to the quarter wave plate again.

In an optional implementation manner of the first aspect, a condensing lens and a collimating lens are disposed between the backlight and the quarter wave plate, so that the illumination light sequentially passes through the condensing lens and the collimating lens to form a uniform light beam.

In an alternative embodiment of the first aspect, the reflecting unit is disposed in a space between the condensing lenses and is connected to the condensing lenses.

In an alternative embodiment of the first aspect, the reflective unit surface is coated with a highly reflective film.

In an optional implementation manner of the first aspect, the backlight source is a group of LED lamp beads arranged.

In an alternative implementation of the first aspect, the image source is an LCD screen.

In a second aspect, the present application provides a display device comprising the light engine of the first aspect.

In a third aspect, the present application provides a vehicle comprising the light engine of the first aspect or the display device of the second aspect.

Compared with the prior art, the reflection type light source has the advantages that the quarter wave plate capable of changing the polarization characteristic of the P polarized light is arranged between the backlight source and the image source, the reflection type polarizer and the reflection unit for realizing light path planning are arranged in a matched mode, the illumination light converts the P polarized light into the S polarized light after passing through the quarter wave plate twice by the reflection type polarizer, and then the converted S polarized light is provided for the image source through the reflection unit, so that the brightness of the image source is improved. The utility model discloses can improve the light utilization efficiency of ray apparatus inside, reduce the consumption of backlight when satisfying luminance, and then reduce the illumination light projection and generate heat the temperature rise that arouses on the image source.

Drawings

In order to more clearly illustrate the technical solutions of the present application, the drawings that are used in the description of the technical solutions will be briefly described below. It is obvious that the drawings in the following description are only some examples described in the present application, and that other drawings may be obtained from these drawings without inventive work for a person of ordinary skill in the art.

Fig. 1 is a schematic view of a HUD projection display in some examples of the present application.

Fig. 2 is a schematic block diagram of an optical engine in some examples of the present application.

Fig. 3 is a schematic structural diagram of a light guiding element of an optical machine in some examples of the present application.

Fig. 4 is a schematic structural diagram of a light guiding element of an optical machine in some examples of the present application.

Fig. 5 is a schematic diagram illustrating the internal components of the optical engine according to some examples of the present application.

Fig. 6 is a schematic diagram illustrating the internal components of the optical engine according to some examples of the present application.

Fig. 7 is a schematic structural diagram of a reflection unit of an optical engine in some examples of the present application.

Fig. 8 is a schematic diagram of a reflection unit of an optical engine in some examples of the present application.

Fig. 9 is a schematic view of an optical machine structure in some examples of the present application.

Fig. 10 is a schematic view of a vehicle in some examples of the present application.

Description of the embodiments

The present application will be described in detail below with reference to the attached drawings, but the descriptions are only examples described in the present application and are not limiting, and all changes in structure, method or function etc. made by those of ordinary skill in the art based on these examples are included in the protection scope of the present application.

It should be noted that in different examples, the same reference numerals or labels may be used, but these do not represent absolute relationships in terms of structure or function. Also, the references to "first," "second," etc. in the examples are for descriptive convenience only and do not represent absolute distinguishing relationships between structures or functions, nor should they be construed as indicating or implying a relative importance or number of corresponding objects. Unless specifically stated otherwise, reference to "at least one" in the description may refer to one or more than one, and "a plurality" refers to two or more than two.

In addition, in representing the feature, the character "/" may represent a relationship in which the front-rear related objects exist or exist, for example, a head-up display/head-up display may be represented as a head-up display or a head-up display. In the expression operation, the character "/" may indicate that there is a division relationship between the front and rear related objects, for example, the magnification m=l/P may be expressed as L (virtual image size) divided by P (image source size). Also, "and/or" in different examples is merely to describe the association relationship of the front and rear association objects, and such association relationship may include three cases, for example, a concave mirror and/or a convex mirror, and may be expressed as the presence of a concave mirror alone, the presence of a convex mirror alone, and the presence of both concave and convex mirrors.

The HUD mainly utilizes the optical reflection principle, imaging light to be displayed is reflected into human eyes through the transparent surface, the human eyes can observe corresponding information along the opposite direction of the light, and a special display screen is not needed, so that another convenient implementation mode is provided for information display. In particular, a transparent surface (such as a windshield) is arranged in the front view of the driver, and if the driver needs to view information when driving the vehicle, the view does not need to be turned to a place beyond the front of the vehicle, so that the driving safety of the driver is improved. In some examples, a HUD display device may be fixedly mounted on a vehicle center console, where the HUD display device includes an optical-mechanical component and an optical lens, and the optical-mechanical component may implement display based on LCD (Liquid Crystal Display ), DLP (Digital Light Processing, digital light processing technology), MEMS laser scanning, LCOS (Liquid Crystal on silicon ) and other technologies, and a display surface of the optical-mechanical component may display an image (display content) to be projected on an imaging position, and projects display light of the image, and finally reflects the display light on a windshield of the vehicle through light path planning of the optical lens, where the windshield serves as a transparent surface for reflecting the display light, and may serve as a display screen, and a driver may directly observe a virtual image corresponding to the display content through the transparent surface, for example, the display content may be navigation information and a vehicle speed.

As shown in fig. 1, the HUD display device may include at least an optical machine 1, a first mirror 2, and a second mirror 3, and in this example, the first mirror 2 and the second mirror 3 cooperate to form an optical path transmission device, and the optical path transmission device may project display light projected by the optical machine 1 onto a windshield 4. In some examples, the first mirror 2, the second mirror 3 may be provided as a concave mirror, a convex mirror, or the like as required. In some examples, the optical path transmission device may also enable planning of the optical path by one or more transmissive mirrors. The optical machine 1 projects light rays for displaying corresponding information, and the first reflecting mirror 2 and the second reflecting mirror 3 are used for realizing light path planning, so that light path customization can be carried out in a smaller space, and different projection display requirements are met. The display light projected by the optical machine 1 is finally projected on the windshield 4 of the vehicle through multiple reflections of the first reflecting mirror 2 and the second reflecting mirror 3, and a driver 6 in the vehicle can see a virtual image 5 formed by the projection light of the optical machine 1 passing through the windshield 4 against the windshield 4, and the virtual image can be corresponding to parameter information of the vehicle and the like. In some examples, the first mirror 2 and the second mirror 3 may also be adjusted to a certain degree of angle, so as to change the projection position of the projection light on the windshield 4, so as to adapt to the heights of different drivers 6. It should be added that different optical machines can be correspondingly provided with a diffuse mirror to adjust the corresponding imaging effect. In some examples, fresnel lenses, waveguide optics, diffractive optics, holographic optics, tapered fibers, etc. may also be included in the HUD display device to enable light path planning and optimization.

As shown in fig. 2, the optical engine 1 includes a backlight 17 and an image source 18, and the backlight 17 and the image source 18 may be integrated into one module or may be separated into two modules. The backlight 17 provides illumination light for the image source 18, and the image source 18 emits corresponding display light under the control of the brightness of the illumination light, wherein the display light contains image information to be displayed. Further, by adjusting the luminance of the illumination light emitted from the backlight 17, the luminance of the display light emitted from the image source 18 can be adjusted, and thus the luminance of the virtual image displayed by projection on the windshield can be adjusted. In some examples, the backlight may be an LED (light emitting diode) lamp, the image source 18 may be an LCD screen, and the liquid crystal in the LCD screen may rotate under the control of an electric field, so as to change the traveling direction of light and the color of the light, and accordingly, when the illumination light emitted from the backlight reaches the image source, the transmission manner of the illumination light is determined by the rotation direction of the liquid crystal in the LCD screen, so as to generate different images, that is, emit display light containing different display information. In order to increase the brightness of the projection of the HUD display device on the windshield, the backlight 17 needs to increase the brightness accordingly, and a large amount of heat is generated during operation to increase the temperature rise of the whole optical-mechanical system, so that the utilization efficiency of the illumination light emitted by the backlight 17 needs to be increased, the energy of the illumination light is transmitted in a light manner as much as possible, and the conversion of the heat is reduced.

It should be noted that, light having a polarization state, light in a natural state (such as sunlight) is in a random polarization state, and light having all different polarization directions is decomposed based on a light incident plane, so that light parallel to the incident plane and perpendicular to the incident plane can be obtained, the former is generally called P-polarized light (P is abbreviated as german parallel), and the latter is S-polarized light (S is abbreviated as german word senkrecht and translated as perpendicular). Since the LCD can only transmit S polarized light and P polarized light is cut off, half of the light efficiency of the illumination light emitted from the backlight is not utilized under the condition of no processing, on the one hand, the light that is not utilized is converted into heat, and on the other hand, in order to compensate for the lost light efficiency, brighter illumination light is needed to improve the brightness of the display light, which inevitably increases the power consumption and also increases the difficulty of heat dissipation of the whole HUD display device.

In some examples, to improve the light utilization efficiency, an optical device for changing the polarization characteristic of the P-polarized light may be disposed between the backlight source and the image source of the optical machine, so that part of the P-polarized light in the illumination light reaching the image source may be converted into S-polarized light, so that more illumination light may be transmitted through the LCD screen, and the brightness of the LCD screen may be improved. Optionally, a quarter wave plate and a reflective polarizer are sequentially arranged on the light path from the backlight source to the image source. The quarter wave plate can normally transmit S polarized light, and the polarization characteristics of P polarized light are changed, and correspondingly, the P polarized light is converted into S polarized light after being transmitted twice by the quarter wave plate. The reflective polarizer can normally transmit S-polarized light and reflect P-polarized light. Thus, in this example, when P-polarized light passes through the quarter wave plate and the reflective polarizer in order, the reflective polarizer may change the direction of the P-polarized light, reflect back to the quarter wave plate, create a chance for the P-polarized light to twice transmit the quarter wave plate, and thereby convert the P-polarized light into S-polarized light. Meanwhile, the quarter wave plate and the reflective polarizer which are sequentially arranged can not influence the normal passing of S polarized light, and the S polarized light in the illumination light can normally provide brightness for an LCD screen.

In some examples, the backlight source firstly conducts a certain light guiding treatment on the light path of the illumination light after the illumination light is emitted, as shown in fig. 3, the condensing lens 11 and the collimating lens 12 are further arranged in the direction of the illumination light projected by the backlight source 17, and taking the backlight source 17 as an example, each LED lamp bead is formed by arranging a group of LED lamp beads, each LED lamp bead can be respectively provided with a group of condensing lens 11 and collimating lens 12, the size of the condensing lens 11 is equivalent to that of a single LED lamp bead, and the collimating lens 12 is relatively larger than the condensing lens 11. Correspondingly, as shown in fig. 4, when a back plate of the backlight source is provided with a plurality of LED beads, the LED beads are arranged according to a certain rule, for example, three LED beads are arranged in a horizontal direction and two vertical directions, and a plurality of groups of condensing lenses 11 and collimating lenses 12 are arranged on the plurality of LED beads. The single LED lamp beads are arranged in the condensing lens 11, the condensing lens 11 can collect illumination light emitted by the LED lamp beads into a certain angle, and loss of scattered light rays around is reduced. Further, the collimator lens 12 is matched with the condenser lens 11, and condenses the light emitted from the condenser lens 11 into nearly parallel light and emits the light. As shown in fig. 4, in order to match with the backlight sources of the LED lamp beads, the collimating lenses 12 are connected together, so that the plane formed by the collimating lenses can emit relatively uniform collimated light, thereby meeting the requirement of uniformity of projection on the image source.

As shown in fig. 5, in some examples, the light engine includes a backlight 17, an image source 18, a light guiding element, a polarized light processing element, and the like. The light guide element includes a condensing lens 11 and a collimating lens 12, and the illumination light emitted from the backlight 17 reaches the reflecting mirror 13 after the light guide treatment of the condensing lens 11 and the collimating lens 12, and the reflecting mirror 13 may be a planar reflecting mirror or a curved reflecting mirror, and optionally, in order to improve the reflection performance of the reflecting mirror 13, a high reflection film is plated on the surface of the reflecting mirror 13. In this example, the mirror 13 is at an angle of 45 degrees to the main optical axis of the illumination light, which ensures that the illumination light is reflected to the image source 18 directly above the mirror 13. It should be noted that, the angle between the reflecting mirror 13 and the main optical axis of the illumination light is not limited to 45 degrees, and depends on the positional relationship between the backlight 17 and the image source 18, and the angle of the reflecting mirror 13 ensures that the illumination light (at least S polarized light) emitted from the backlight 17 can be projected on the image source 18. Alternatively, the mirror 13 may be provided with a first adjusting structure, which may be a rotating bracket fixed on the back of the mirror 13, where the rotating bracket may drive the mirror 13 to rotate under the action of an external force, for example, an external force applied by a motor, and accordingly, a specific rotation angle may also be determined by motor control. The mirror 13 can adjust the angle between the mirror 13 and the main optical axis of the illumination light according to the first adjusting structure, so that the path of the illumination light reflected on the mirror 13 can be changed to match different structures of the optical machine.

As described above, the illumination light is transmitted vertically upwards by reflection of the reflecting mirror 13, and before reaching the image source 18, the illumination light includes the S-polarized light and the P-polarized light, which directly pass through the quarter-wave plate 14 and the reflecting polarizer 15 to reach the image source 18 due to the light characteristics, and the image source 18 is normally provided with brightness. And the P polarized light after passing through the quarter wave plate 14 is reflected on the surface of the reflective polarizer 15 opposite to the quarter wave plate 14. It should be noted that, the P polarized light is transmitted through the quarter wave plate 14 once before being reflected by the surface of the reflective polarizer 15, so that the polarization characteristic of the P polarized light is changed once, the light path of the P polarized light is changed after being reflected by the reflective polarizer 15, and returns to the quarter wave plate 14 again, and the P polarized light is changed twice after being transmitted through the quarter wave plate 14, i.e. the P polarized light is normally converted into S polarized light, and at this time, the brightness of the image source 18 can be further improved by only providing the converted S polarized light to the image source 18. In this example, the converted S-polarized light multiplexes the mirror 13, and changes direction again by reflection of the mirror 13, so that the converted S-polarized light is not affected by the quarter wave plate 14 and the reflective polarizer 15, and is transmitted directly to the image source 18. In order to ensure that the back-and-forth reflection path between the reflective polarizer 15 and the reflecting mirror 13 meets the requirement, for example, the light reflected by the reflective polarizer 15 can reach the reflecting mirror 13, the light reflected by the reflecting mirror 13 can reach the image source 18, further, the requirement of uniformity of the related light can also be met, correspondingly, the reflective polarizer 15 can be further adjusted on the premise of determining the angle of the reflecting mirror 13, the reflective polarizer 15 can be provided with a second adjusting structure, the second adjusting structure can also be a rotating bracket, the rotating bracket can drive the reflective polarizer 15 to rotate under the action of external force, and optionally, the external force can be completed by a motor arranged inside the optical machine.

In some examples, as shown in fig. 6, the backlight source 17 and the image source 18 in the optical engine may be on the same straight line, and as described above, the illumination light emitted by the backlight source 17 may first pass through the condensing lens 11 and the collimating lens 12, and the light emitted by the single LED lamp beads may be converged by the cooperation between the condensing lens 11 and the collimating lens 12, and form a uniform light emitting surface to be transmitted to the image source 18 in a parallel and collimated direction. For a backlight source with a plurality of LED beads, a plurality of groups of condensing lenses 11 and collimating lenses 12 are disposed, the distribution sparseness of the condensing lenses 11 and the number of the LED beads are determined, a gap exists between the condensing lenses 11, and a reflecting unit may be disposed on the gap, which will be described in detail below. In order to ensure that each point of the light emitting surface opposite to the image source has uniform collimated light, the cross section of the collimating lens 12 is larger than that of the condensing lens 11, meanwhile, adjacent collimating lenses 12 are mutually connected to form a complete light emitting surface, and under the condition that a plurality of LED lamp beads emit illumination light, parallel light can be projected on each point of the light emitting surface.

The parallel light projected from the collimator lens 12 includes P-polarized light and S-polarized light, and the corresponding light passes through the quarter-wave plate 14 and the reflective polarizer 15 in sequence, as described above, the paths of the S-polarized light are not changed by the quarter-wave plate 14 and the reflective polarizer 15, and thus the S-polarized light is always transmitted upward to the image source 18. Whereas for P polarized light, the first pass through the quarter wave plate 14, the quarter wave plate 14 changes the polarization characteristics of the P polarized light. Through the reflective polarizer 15, the reflective polarizer 15 reflects the P polarized light, and in this example, the reflective surface of the reflective polarizer 15 opposite to the P polarized light faces the direction of the backlight 17, so the P polarized light returns in the original path under the effect of reflection, and passes through the quarter wave plate 14 for the second time, and at this time, the quarter wave plate 14 can convert the P polarized light passing back through the two times into S polarized light, that is, light that can pass through the image source 18 (LCD screen). However, since the light is redirected by the reflective polarizer 15 at this time, it is necessary to provide a reflection unit to redirect the light again so that it can finally reach the image source 18.

In order to change the transmission direction of the converted S-polarized light, a reflection unit that changes the optical path may be provided between the quarter wave plate 14 and the backlight 17. As shown in fig. 7, a reflecting unit may be provided in a space between the condensing lenses 11, and a plurality of condensing lenses may be coupled together to form one complete surface. Specifically, any adjacent condensing lenses 11 can be connected with each other through a bearing plate, the bearing plate can be provided with a plurality of through holes corresponding to the condensing lenses 11 in size, the positions of the through holes correspond to the positions of the LED lamp beads on the backlight 17, and each condensing lens 11 is installed on the corresponding through hole, so that light rays can be ensured to normally penetrate through the condensing lens 11. The other parts 131 of the carrier plate, that is, the gaps between the condensing lenses 11, may be provided with reflective materials similar to a mirror as a reflective unit on the surfaces of the other parts 131 of the carrier plate, and optionally, may be coated with a high reflective film on the surfaces of the other parts 131 of the carrier plate. Accordingly, the illumination light emitted by the LED lamp beads enters the condensing lens 11 from the surface of the carrier plate opposite to the backlight source 17, so that the illumination light cannot reach the reflecting unit to generate reflection, and the illumination light coming out of the condensing lens 11 enters the collimating lens 12 and is then transmitted to the image source 18, which is not described herein. As described above, the S polarized light after the second transmission through the quarter wave plate 14 reaches the space between the condensing lenses 11, that is, the reflecting unit disposed on the carrier plate, and the reflecting unit has reflection performance, so that the converted S polarized light changes its light direction, and at this time, the converted S polarized light passes through the collimating lens 12 as the S polarized light emitted from the backlight 17, and then passes through the quarter wave plate 14 for the third time, and since the P polarized light has been converted into the S polarized light, the S polarized light can normally pass through the quarter wave plate 14 and the reflective polarizer 15, and reach the image source 18, so as to provide brightness for the image source 18.

As shown in fig. 8, in some examples, the reflecting unit may also be disposed on the space between the luminous bodies. Specifically, the illuminant of the backlight source is LED lamp beads arranged on the back plate according to a certain rule, corresponding conducting circuits can be arranged on the back plate for each LED lamp bead to supply electric energy, and the condensing lens 11 is arranged on the LED lamp beads to collect light emitted by the LED lamp beads into a certain angle. More importantly, the reflecting units can be arranged on the gap parts 132 of the back plate, on which the LED lamp beads are not arranged, namely the back plate is respectively composed of a plurality of LED lamp beads and a plurality of reflecting units, and optionally, the reflecting units are correspondingly plated with high reflecting films. Similarly, because the LED lamp beads are matched with the condensing lens 11 and are correspondingly arranged in the condensing lens, the illumination light emitted by the LED lamp beads directly enters the condensing lens 11 and cannot reach the reflecting unit on the back plate to generate reflection, and the illumination light from the condensing lens 11 also enters the collimating lens 12, which is not described herein. As described above, the S polarized light converted by the quarter wave plate 14 after passing through the collimating lens 12 and the condensing lens 11 for the second time reaches the gap 132 between the LED beads, that is, the reflecting unit disposed on the back plate, and the reflecting unit has the light reflection property, so that the converted S polarized light changes its light direction, and the S polarized light passes through the gap between the condensing lenses 11, and then passes through the collimating lens 12 as the S polarized light emitted from the backlight 17, and then passes through the quarter wave plate 14 for the third time, and the P polarized light is converted into S polarized light at this time, so that the S polarized light can normally pass through the quarter wave plate 14 and the reflecting polarizer 15 to reach the image source 18, thereby providing brightness for the image source 18.

In some examples, the reflective polarizer 15 is provided with a second adjusting structure capable of changing an angle, and the second adjusting structure can enable the reflective polarizer 15 not to be perpendicular to a main optical axis of illumination light emitted by the backlight source 17, for example, the reflective polarizer 15 can be opposite to one surface of the quarter wave plate 14 to deflect outwards, so that P polarized light in the illumination light can be ensured to be transmitted outwards at a certain angle with the main optical axis of the illumination light after being reflected on the reflective polarizer 15, and the position where the collimating lens 12 and the condensing lens 11 are located can be directly deviated after the P polarized light is converted into S polarized light through the quarter wave plate 14. At this time, a reflecting mirror may be disposed at a position adjacent to the collimator lens 12 or the condenser lens 11 as a separate reflecting unit for changing the direction of the converted S-polarized light, and the reflected S-polarized light may be transmitted in the direction of the image source 18. Optionally, a first adjusting structure is provided for the reflecting unit, and the angle of the reflecting unit is adjusted by the first adjusting structure to meet the reflecting requirement of the converted S polarized light. In some examples, the converted S-polarized light is reflected and transmitted through the quarter-wave plate 14 and the reflective polarizer 15 to reach the image source 18, and in some examples, the converted S-polarized light is reflected and does not pass through the quarter-wave plate 14 and the reflective polarizer 15 and directly reach the image source 18.

Referring to the above examples, the optical engine includes an image source having an LCD screen and a backlight source for providing illumination light to the image source, wherein a quarter wave plate and a reflective polarizer are sequentially disposed on an optical path from the backlight source to the image source, and a reflective unit is further provided in cooperation with the reflective polarizer, and the reflective polarizer and the reflective unit together guide light transmission, so that final light is transmitted to the image source, and brightness is provided to the image source. The illumination light emitted from the backlight is composed of P-polarized light and S-polarized light, and the two lights have different polarization characteristics, so that different light transmission paths are presented through the optical element. Further, the P-polarized light is subjected to the twice polarization characteristic change of the quarter wave plate on the transmission path, so that the P-polarized light is also finally converted into S-polarized light and reaches the image source under the reflection of the reflection unit. The structure does not need to add excessive optical elements, occupies small space in the optical machine, can convert most of light in illumination light into S-polarized light which can be transmitted by an imaging source, and greatly improves the utilization efficiency of light.

As shown in fig. 9, in some examples, the light machine 1 is integrated in the HUD display device 100, and since the light machine 1 can use the brightness of the S-polarized light and the P-polarized light at the same time, the light utilization efficiency is high, so that the brightness of the display light projected by the light machine 1 is also higher, and the generated heat is also controlled to a certain extent. Specifically, the HUD display device 100 includes a housing that forms an inner space accommodating related elements by enveloping, and mounts the optical machine 1 and the first and

second mirrors

2, 3 inside the housing by brackets or the like, and the first and

second mirrors

2, 3 project display light generated by the optical machine 1 out of a window on the housing by cooperation. When the HUD display device 100 is embedded in a center console of an automobile, the window in the housing faces the vehicle windshield above the center console, and accordingly, the projected display light reflects off the windshield to form a virtual image that can be seen by the human eye.

As shown in fig. 10, in some examples, the HUD display device described above may be integrated in a vehicle, and the corresponding parameter information is projected onto a vehicle windshield by projection, so that the windshield is viewed from within the cockpit, that is, the traveling speed and navigation route information of the vehicle, and the like, can be seen. The driver can look over information at windshield in the in-process of driving, need not to look over traditional panel board low, has improved the security of driving. The vehicle is not limited to the automobile shown in fig. 10, and may include buses, trucks, excavators, motorcycles, trains, high-speed rails, ships, yachts, airplanes, spacecraft, and the like. The projected windshield is not limited to the front windshield of the automobile, and may be a transparent surface in other positions.

In summary, the quarter wave plate capable of changing the polarization characteristic of the P polarized light is arranged between the backlight source and the image source, the reflective polarizer and the reflective unit for realizing light path planning are arranged in a matched mode, the illumination light converts the P polarized light into the S polarized light after passing through the quarter wave plate twice by the reflective polarizer, and then the converted S polarized light is provided for the image source through the reflective unit, so that the brightness of the image source is improved. The utility model discloses can improve the light utilization efficiency of ray apparatus inside, reduce the consumption of backlight when satisfying luminance, and then reduce the illumination light projection and generate heat the temperature rise that arouses on the image source.

It should be understood that while this specification includes examples, any of these examples does not include only a single embodiment, and that this depiction of the specification is for clarity only. Those skilled in the art will recognize that the embodiments of the present invention may be combined as appropriate with one another to form other embodiments as would be apparent to one of ordinary skill in the art.

The above list of detailed descriptions is only specific to possible embodiments of the present application, they are not intended to limit the scope of the present application, and all equivalent embodiments or modifications that do not depart from the teachings of the present application are intended to be included in the scope of the present application.

Claims

1. A light engine, comprising:

the backlight source provides illumination light for the image source;

2. The light engine of claim 1, wherein S polarized light of the illumination light is directly projected onto the image source through transmission of the quarter wave plate, reflective polarizer.

3. The light engine of claim 1, wherein the reflecting units are disposed on the back plate corresponding to the backlight and are disposed in a gap between the light emitters.

4. The light engine of claim 1, wherein the reflecting unit is a mirror disposed between the backlight and the quarter wave plate, and the reflecting unit is further configured to reflect illumination light emitted by the backlight onto the quarter wave plate.

5. The light engine of claim 4, wherein the reflective unit is provided with a first adjustment structure to adjust the reflection angle of the illumination light.

6. The light engine of claim 1, wherein a condenser lens and a collimator lens are disposed between the backlight and the quarter wave plate, so that the illumination light sequentially passes through the condenser lens and the collimator lens to form a uniform light beam.

7. The bare engine according to claim 6, wherein the reflecting unit is disposed in a space between the condenser lenses and is connected to the condenser lenses.

8. The light engine of claim 1, wherein the backlight is a group of LED light beads and the image source is an LCD screen.

9. A display device comprising a light engine as claimed in any one of claims 1-8.

10. A vehicle comprising a light engine according to any one of claims 1-8, or a display device according to claim 9.