Heads up display and vehicle

Abstract

A heads up display (HUD) includes a first reflective polarizer, different first and second displays disposed on opposite respective first and second major sides of the first reflective polarizer. The first and second displays form and emit respective first and second emitted image lights having substantially mutually orthogonal first and second polarization states and including respective first and second images. The HUD forms respective first and second real images of the first and second images for viewing by an eye of a same first occupant of the vehicle. The first reflective polarizer receives and respectively transmits and reflects at least 40% of the first and second emitted image lights as respective first transmitted and second reflected image lights. The HUD further includes an optical mirror configured to receive and reflect at least 10% of the first transmitted and second reflected image lights toward the eye of the same first occupant.

Description

[0001] HEADS UP DISPLAY AND VEHICLE

[0002] Technical Field

[0003] The present disclosure relates to a heads up display (HUD) and a vehicle including the heads up display.

[0004] Background

[0005] A heads up display (HUD) may be used in a vehicle to present various information to one or more occupants on a windshield of the vehicle. A typical HUD may include one or more displays and several components for reflecting and directing emitted lights from the one or more displays to present the various information to the one or more occupants.

[0006] Summary

[0007] In a first aspect, the present disclosure provides a heads up display (HUD) for use in a vehicle. The HUD includes a first reflective polarizer, different first and second displays, and an optical mirror. The first and second displays are disposed on opposite respective first and second major sides of the first reflective polarizer. The first and second displays are configured to form and emit respective first and second emitted image lights toward the first reflective polarizer. The first and second emitted image lights have substantially mutually orthogonal first and second polarization states and include respective first and second images. The HUD is configured to form respective first and second real images of the first and second images for viewing by an eye of a same first occupant of the vehicle. The first reflective polarizer is configured to receive and respectively transmit and reflect at least 40% of the first and second emitted image lights as respective first transmitted and second reflected image lights. The optical mirror is configured to receive and reflect at least 10% of the first transmitted and second reflected image lights toward the eye of the same first occupant.

[0008] In a second aspect, the present disclosure provides a vehicle. The vehicle includes the HUD of the first aspect.

[0009] In a third aspect, the present disclosure provides a heads up display (HUD) for use in a vehicle. The HUD includes a housing, a first reflective polarizer, a second reflective polarizer, an optical mirror, and first, second, and third displays. The housing has a top side defining an opening. The first reflective polarizer is at least partially disposed inside the housing. The second reflective polarizer and the optical mirror are at least partially disposed outside the housing on a same optically transmissive substrate. The first, second, and third displays are at least partially disposed inside the housing and are configured to form and emit respective first, second, and third images. The HUD is configured to form respective first real, second real, and third virtual images of the first, second, and third images for viewing by one or more viewers. The first reflective polarizer is configured to receive and respectively transmit and reflect at least lights. The second reflective polarizer is configured to receive and reflect at least 40% of the third emitted image light. The optical mirror is configured to receive and reflect at least 30% of the first transmitted and second reflected image lights.

[0010] The details of one or more examples of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the disclosure will be apparent from the description and drawings, and from the claims.

[0011] Brief Description of the Drawings

[0012] Exemplary embodiments disclosed herein may be more completely understood in consideration of the following detailed description in connection with the following figures. The figures are not necessarily drawn to scale. Like numbers used in the figures refer to like components. However, it will be understood that the use of a number to refer to a component in a given figure is not intended to limit the component in another figure labeled with the same number.

[0013] FIGS. 1A-1B show schematic views of exemplary vehicles;

[0014] FIG. 2 shows a schematic view of a heads up display (HUD), according to an embodiment of the present disclosure;

[0015] FIG. 3 shows a schematic diagram illustrating a relative placement of first and second displays of the HUD, according to an embodiment of the present disclosure;

[0016] FIGS. 4A-4C show different schematic views of different positionings of first and second real images, according to an embodiment of the present disclosure;

[0017] FIG. 5 shows a schematic top view of a display of the HUD, according to an embodiment of the present disclosure;

[0018] FIG. 6 shows a detailed sectional view of a reflective polarizer of the HUD, according to an embodiment of the present disclosure;

[0019] FIG. 7 shows a schematic view of the HUD, according to another embodiment of the present disclosure;

[0020] FIG. 8 is a schematic view of the HUD, according to another embodiment of the present disclosure.

[0021] Detailed Description

[0022] In the following description, reference is made to the accompanying figures that form a part thereof and in which various embodiments are shown by way of illustration. It is to be understood that other embodiments are contemplated and may be made without departing from the scope or spirit of the present disclosure. The following detailed description, therefore, is not to be taken in a limiting sense.

[0023] In the following disclosure, the following definitions are adopted.

[0024] As used herein, all numbers should be considered modified by the term “about”. As used herein, “a,” “an,” “the,” “at least one,” and “one or more” are used interchangeably.

[0025] As used herein as a modifier to a property or attribute, the term “generally”, unless otherwise specifically defined, means that the property or attribute would be readily recognizable by a person of ordinary skill but without requiring absolute precision or a perfect match (e.g., within + / - 20 % for quantifiable properties).

[0026] The term “substantially”, unless otherwise specifically defined, means to a high degree of approximation (e.g., within + / - 10% for quantifiable properties) but again without requiring absolute precision or a perfect match.

[0027] The term “about”, unless otherwise specifically defined, means to a high degree of approximation (e.g., within + / - 5% for quantifiable properties) but again without requiring absolute precision or a perfect match.

[0028] As used herein, the terms “first” and “second” are used as identifiers. Therefore, such terms should not be construed as limiting of this disclosure. The terms “first” and “second” when used in conjunction with a feature or an element can be interchanged throughout the embodiments of this disclosure.

[0029] As used herein, “at least one of A and B” should be understood to mean “only A, only B, or both A and B”.

[0030] A heads up display (HUD) may be used in a vehicle to present various information to one or more occupants on a windshield of the vehicle. A typical HUD may include one or more displays and several components for reflecting and directing emitted lights from the one or more displays to present the various information to the one or more occupants.

[0031] The present disclosure relates to a heads up display (HUD) for use in a vehicle. The HUD includes a first reflective polarizer, different first and second displays, and an optical mirror. The first and second displays are disposed on opposite respective first and second major sides of the first reflective polarizer. The first and second displays are configured to form and emit respective first and second emitted image lights toward the first reflective polarizer. The first and second emitted image lights have substantially mutually orthogonal first and second polarization states and include respective first and second images. The HUD is configured to form respective first and second real images of the first and second images for viewing by an eye of a same first occupant of the vehicle. The first reflective polarizer is configured to receive and respectively transmit and reflect at least 40% of the first and second emitted image lights as respective first transmitted and second reflected image lights. The optical mirror is configured to receive and reflect at least 10% of the first transmitted and second reflected image lights toward the eye of the same first occupant.

[0032] The first and second real images of the first and second images formed by the HUD may be at least partially combined or overlaid, whether colinearly or offset from each other, for viewing by the same first occupant. Therefore, the HUD may provide a more immersive information environment and differentiation between information displayed on the first and second real images. This may provide a unique experience in terms of how the same first occupant may receive and interact with the information.

[0033] Referring now to figures, FIGS. 1A-1B show schematic views of exemplary vehicles 310. The vehicle 310 includes a windshield 50. In some embodiments, the vehicle 310 may have a first occupant 320. In some embodiments, the first occupant 320 of the vehicle 310 is a driver of the vehicle 310. In some embodiments, the first occupant 320 of the vehicle 310 is a passenger of the vehicle 310. In some embodiments, the vehicle 310 may have a second occupant 325. In some embodiments, the second occupant 325 of the vehicle 310 is the driver of the vehicle 310. In some embodiments, the second occupant 325 of the vehicle 310 is the passenger of the vehicle 310.

[0034] Referring to FIGS. 1A and IB, in some embodiments, the vehicle 310 is a car as shown in FIG. 1 A, a truck 310a, a bus 310b, a train 310c, a ship 3 lOd, a boat 3 lOe, an airplane 3 lOf, or a helicopter 310g.

[0035] FIG. 2 is a schematic view of a heads up display (HUD) 300 for use in the vehicle 310 shown in FIGS. 1A-1B, according to an embodiment of the present disclosure. In some embodiments, the vehicle 310 includes the HUD 300. The HUD 300 includes a first reflective polarizer 10 and different first and second displays 20, 30.

[0036] The first reflective polarizer 10 includes opposite first and second major sides 11, 12. The first and second displays 20, 30 are disposed on the opposite respective first and second major sides 11, 12 of the first reflective polarizer 10. Specifically, the first display 20 is disposed on the first major side 11 of the first reflective polarizer 10 and the second display 30 is disposed on the second major side 12 of the first reflective polarizer 10. In some embodiments, the first reflective polarizer 10 is closer to one of the first and second displays 20, 30 and farther from the other one of the first and second displays 20, 30. In the illustrated embodiment of FIG. 2, the first reflective polarizer 10 is closer to the first display 20 and farther from the second display 30.

[0037] In some embodiments, at least one of the first and second displays 20, 30 includes an organic light emitting diode (OLED) display. In some embodiments, at least one of the first and second displays 20, 30 includes a liquid crystal display (LCD) panel.

[0038] The first and second displays 20, 30 are configured to form and emit respective first and second emitted image lights 21, 31. Specifically, the first display 20 is configured to form and emit first emitted image light 21 and the second display 30 is configured to form and emit second emitted image light 31.

[0039] The first and second emitted image lights 21, 31 have substantially mutually orthogonal first and second polarization states. In other words, the first emitted image light 21 has the first polarization state, and the second emitted image light 31 has the second polarization state, where the second polarization state is substantially orthogonal to the first polarization state.

[0040] The first and second emitted image lights 21, 31 include respective first and second images 22, 32. Specifically, the first emitted image light 21 includes the first image 22 and the second emitted image light 31 includes the second image 32. In some embodiments, at least one of the first and second images 22, 32 includes one or more of a letter, a number, a symbol, a logo, a text, an alphanumeric, a movie, and a picture.

[0041] The first and second images 22, 32 are used to generate respective first and second real images 23, 33. Specifically, the first image 22 is used to generate the first real image 23 and the second image 32 is used to generate the second real image 33. More specifically, the HUD 300 is configured to form the respective first and second real images 23, 33 of the first and second images 22, 32 for viewing by an eye 315 of the same first occupant 320 (shown in FIG. 1A) of the vehicle 310 (shown in FIG. 1A).

[0042] In some embodiments, sizes of the first and second real images 23, 33 are substantially equal to sizes of the respective first and second displays 20, 30. In other words, the size of the first real image 23 is substantially equal to the size of the first display 20 and the size of the second real image 33 is substantially equal to the size of the second display 30.

[0043] The first and second displays 20, 30 are configured to form and emit the respective first and second emitted image lights 21, 31 toward the first reflective polarizer 10. Specifically, the first display 20 forms and emits the first emitted image light 21 towards the first reflective polarizer 10 and the second display 30 forms and emits the second emitted image light 31 towards the first reflective polarizer 10.

[0044] The first reflective polarizer 10 is configured to receive the first and second emitted image lights 21, 31 and is further configured to respectively transmit and reflect the first and second emitted image lights 21, 31 as respective first transmitted and second reflected image lights 24, 34. Specifically, the first reflective polarizer 10 receives the first emitted image light 21 and transmits the first emitted image light 21 as the first transmitted image light 24. Similarly, the first reflective polarizer 10 receives the second emitted image light 31 and reflects the second emitted image light 31 as the second reflected image light 34.

[0045] In some embodiments, the first reflective polarizer 10 is configured to receive and respectively transmit and reflect at least 40% of the first and second emitted image lights 21, 31 as the respective first transmitted and second reflected image lights 24, 34. Specifically, the first reflective polarizer 10 is configured to receive and transmit at least 40% of the first emitted image light 21 as the first transmitted image light 24. Further, the first reflective polarizer 10 is configured to receive and reflect at least 40% of the second emitted image light 31 as the second reflected image light 34. In some embodiments, the first reflective polarizer 10 is configured to receive and respectively transmit and reflect at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 95% of the first and second emitted image lights 21, 31 as the respective first transmitted and second reflected image lights 24, 34.

[0046] In some embodiments, the HUD 300 further includes a second reflective polarizer 13 and a third display 60. The third display 60 is different from the first and second displays 20, 30.

[0047] The third display 60 is configured to form and emit a third emitted image light 61 towards the second reflective polarizer 13. The third emitted image light 61 includes a third image 62. In some embodiments, the HUD 300 is configured to form a third virtual image 63 of the third image 62 for viewing by an eye of the second occupant 325 (shown in FIG. 1 A) of the vehicle 310 (shown in FIG. 1 A). In some cases, the second occupant 325 is the first occupant 320 (shown in FIG. 1 A). In such cases, the eye of the second occupant 325 may be the eye 315.

[0048] In some embodiments, the windshield 50 of the vehicle 310 includes the second reflective polarizer 13. In some embodiments, the windshield 50 further includes first and second glass portions 51, 52. In some embodiments, the second reflective polarizer 13 is disposed between, and bonded to, the first and second glass portions 51, 52 of the windshield 50. In some cases, the first and second glass portions 51, 52 may be interchangeably referred to as “the optically transmissive substrates 51, 52”.

[0049] In some embodiments, the second reflective polarizer 13 is configured to receive and reflect at least 10% of the third emitted image light 61 as a third reflected image light 64 toward the eye of the second occupant 325. In some embodiments, the second reflective polarizer 13 is configured to receive and reflect at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 95% of the third emitted image light 61 as the third reflected image light 64 toward the eye of the second occupant 325.

[0050] In some embodiments, the HUD 300 may not include the second reflective polarizer 13. In such embodiments, the third display different is configured to form and emit the third emitted image light 61 toward the windshield 50. Further, the windshield 50 is configured to receive and reflect at least 10% of the third emitted image light 61 as the third reflected image light 64 toward the eye of the second occupant 325.

[0051] The HUD 300 further includes an optical mirror 40. In some embodiments, the optical mirror 40 is disposed on the windshield 50 of the vehicle 310. In some embodiments, the windshield 50 includes the optical mirror 40.

[0052] In some embodiments, the optical mirror 40 includes a component 41. In some embodiments, the component 41 may be a reflector. In some other embodiments, the component 41 may be a third reflective polarizer. Therefore, the component 41 may be interchangeably referred to as “the reflector 41” or “the third reflective polarizer 41”.

[0053] In some embodiments, the optical mirror 40 is at least a partially opaque optical mirror, and hence, may be interchangeably referred to as “the opaque optical mirror 40”. In some embodiments, the opaque optical mirror 40 includes the reflector 41 and an absorber 42. In some embodiments, the reflector 41 is disposed on the absorber 42. In some embodiments, the reflector 41 is disposed between the absorber 42, and the first and second displays 20, 30.

[0054] The optical mirror 40 is configured to receive and reflect at least 10% of the first transmitted and second reflected image lights 24, 34 toward the eye 315 of the same first occupant 320 (shown in FIG. 1 A). In some embodiments, the optical mirror 40 is configured to receive and reflect at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 95% of the first transmitted and second reflected image lights 24, 34 toward the eye 315 of the same first occupant 320.

[0055] In some embodiments, the optical mirror 40 is configured to receive the first transmitted and second reflected image lights 24, 34 and reflect at least portions 25, 35 of the first transmitted and second reflected image lights 24, 34. Specifically, the optical mirror 40 is configured to receive the first transmitted image light 24 and reflect at least the portion 25 of the first transmitted image light 24 toward the eye 315 of the same first occupant 320. Similarly, the optical mirror 40 is configured to receive the second reflected image light 34 and reflect at least the portion 35 of the second reflected image light 34 toward the eye 315 of the same first occupant 320.

[0056] In some embodiments, the opaque optical mirror 40 has an optical transmittance of less than about 30% for at least one visible wavelength in a visible wavelength range extending from about 420 nanometers (nm) to about 680 nm. In some embodiments, the opaque optical mirror 40 has the optical transmittance of less than about 25%, less than about 20%, less than about 15%, less than about 10%, less than about 8%, less than about 6%, less than about 4%, less than about 2%, less than about 1%, less than about 0.5%, or less than about 0.1% for the at least one visible wavelength in the visible wavelength range. In some embodiments, at least one of the first and second displays 20, 30 is coupled to a positioner 100, 101 configured to change at least one or more of an axial position, a lateral position, a tilt, and an orientation of the display relative to the optical mirror 40. In the illustrated embodiment of FIG. 2, the first display 20 is coupled to the positioner 100 to adjust the first display 20 relative to the optical mirror 40, and the second display 30 is coupled to the positioner 101 to adjust the second display 30 relative to the optical mirror 40.

[0057] In some embodiments, the first and second displays 20, 30 are so positioned and oriented, and the first and second images 22, 32 having intensities and contents, so as to generate a depth perception of the first and second real images 23, 33 by the first occupant 320.

[0058] In some embodiments, the first and second displays 20, 30 are so positioned and oriented, the first and second images 22, 23 having intensities and contents, and the first and second real images 23, 33 are so spaced from each other, so as to generate a perception of a three-dimensional single real image by the first occupant 320.

[0059] In some embodiments, the vehicle 310 includes a dashboard 80. The dashboard 80 includes a top portion 81 and a dashboard opening 82. The top portion 81 faces the optical mirror 40 and defines the dashboard opening 82.

[0060] In some embodiments, the first and second displays 20, 30 are at least partially disposed inside the dashboard 80 of the vehicle 310. In addition, in some embodiments, the optical mirror 40 is at least partially disposed outside the dashboard 80. In some embodiments, the first transmitted and the second reflected image lights 24, 34 exit the dashboard 80 through the dashboard opening 82 before being received and reflected by the optical mirror 40.

[0061] Therefore, the first and second displays 20, 30 may be shielded from direct view by the occupants (i.e. , the first occupant 320 and / or the second occupant 325), such that only the first and second real images 23, 33 may be seen by the occupants.

[0062] In some embodiments, the HUD 300 further includes a magnifying mirror 90 for magnifying the third image 62. The second reflective polarizer 13 is configured to receive and reflect the third emitted image light 61 after the third emitted image light 61 is received and reflected by the magnifying mirror 90 as a magnified reflected third emitted image light 65. As discussed above, in some embodiments, the HUD 300 may not include the second reflective polarizer 13. In such embodiments, the windshield 50 is configured to receive and reflect the third emitted image light 61 after the third image light 61 is received and reflected by the magnifying mirror 90. in some embodiments, the HUD 300 further includes a folding mirror 91 for receiving and reflecting the third emitted image light 61 toward the magnifying mirror 90. in some embodiments, the folding mirror 91 receives the third emitted image light 61 and reflects the third emitted image light 61 as a reflected third emitted image light 66 towards the magnifying mirror 90. in some embodiments, the magnifying mirror 90 receives the reflected third emitted image light 66 from the folding mirror 91 and reflects the magnified reflected third emitted image light 65 towards the second reflective polarizer 13. In some embodiments, a lateral dimension of the third virtual image 63 is greater than a corresponding lateral dimension of the third display 60 by at least a factor of 10. In some embodiments, the lateral dimension of the third virtual image 63 is greater than the corresponding lateral dimension of the third display 60 by at least a factor of 50, at least a factor of 100, at least a factor of 500, or at least a factor of 1000.

[0063] In some embodiments, a maximum lateral dimension of the third virtual image 63 is greater than a maximum lateral dimension of each of the first and second real images 23, 33 by at least a factor of 2. In some embodiments, the maximum lateral dimension of the third virtual image 63 is greater than the maximum lateral dimension of each of the first and second real images 23, 33 by at least a factor of 5, at least a factor of 10, at least a factor of 20, at least a factor of 30, at least a factor of 40, at least a factor of 50, at least a factor of 100, at least a factor of 500, or at least a factor of 1000.

[0064] In some embodiments, the dashboard 80 may be a part of the HUD 300 and may be referred to as “the housing 80” of the HUD 300. In such cases, the top portion 81 of the dashboard 80 may be interchangeably referred to as “the top side 81”, and the dashboard opening 82 may be interchangeably referred to as “the opening 82” . In the embodiments, the housing 80 has the top side 81 defining the opening 82.

[0065] In the embodiments, the first reflective polarizer 10 is at least partially disposed inside the housing 80. Further, the second reflective polarizer 13 and the optical mirror 40 are at least partially disposed outside the housing 80 on the same optically transmissive substrate 51, 52. Moreover, the first, second, and third displays 20, 30, 60 are at least partially disposed inside the housing 80 and are configured to form and emit the respective first, second, and third images 22, 32, 62.

[0066] The HUD 300 is configured to form the respective first real, second real, and third virtual images 23, 33, 63 of the first, second, and third images 22, 32, 62 for viewing by one or more viewers (e.g., the first and second occupants 320, 325).

[0067] Therefore, the HUD 300 may be compact and may be configured to form real as well as virtual images. Moreover, the HUD 300 may be configured to combine the third virtual image 63 with the first real image 23 and / or the second real image 33.

[0068] FIG. 3 is a schematic diagram showing a relative placement of the first and second displays 20, 30 of the HUD 300 shown in FIG. 2, according to an embodiment of the present disclosure.

[0069] As shown in FIG. 3, the first and second displays 20, 30 include respective first and second display surfaces 26, 36. Specifically, the first display 20 includes the first display surface 26 and the second display 30 includes the second display surface 36. In some embodiments, the first and second display surfaces 26, 36 make an oblique angle al therebetween.

[0070] In some embodiments, the first and second images 22, 32 (shown in FIG. 2) are formed and displayed on the respective first and second display surfaces 26, 36 of the respective first and second displays 20, 30. Specifically, the first image 22 is formed and displayed on the first display surface 26 of the first display 20 and the second image 32 is formed and displayed on the second display surface 36 of the second display 30. FIGS. 4A-4C are schematic views of different positionings of the first and second real images 23, 33, according to an embodiment of the present disclosure.

[0071] As shown in FIGS. 4A and 4B, in some embodiments, the first and second real images 23, 33 are not co-planar.

[0072] Further, as shown in FIG. 4 A, the first and second real images 23, 33 include respective first and second real images 23A, 33A. In some embodiments, the first and second real images 23A, 33A make an oblique angle a2 with each other.

[0073] In some embodiments, the first and second real images 23 A, 33A make the oblique angle a2 of less than about 80 degrees with each other. In some embodiments, the first and second real images 23 A, 33 A make the oblique angle a2 of less than about 70 degrees, less than about 60 degrees, less than about 50 degrees, less than about 40 degrees, less than about 30 degrees, less than about 20 degrees, or less than about 10 degrees with each other.

[0074] As shown in FIG. 4B, the first and second real images 23, 33 include respective first and second real images 23B, 33B. In some embodiments, the first and second real images 23B, 33B are substantially parallel with each other.

[0075] As shown in FIG. 4C, the first and second real images 23, 33 include respective first and second real images 23C, 33C. In some embodiments, the first and second real images 23C, 33C are substantially co-planar. In some embodiments, the first and second real images 23C, 33C at least partially overlap one another.

[0076] Referring to FIGS. 4A-4C, the different positionings of the first and second images 22, 32 may generate a depth perception of the first and second real images 23, 33 and / or a perception of a three- dimensional single real image, as per desired application attributes.

[0077] Therefore, the HUD 300 shown in FIG. 2 may provide a more immersive information environment and differentiation between information displayed on the first and second real images 23, 33. This may provide a unique experience in terms of how the occupants (i.e. , the first occupant 320 and / or the second occupant 325) may receive and interact with the information.

[0078] FIG. 5 is a schematic top view of a display, according to an embodiment of the present disclosure.

[0079] The display may be the first display 20, the second display 30, or the third display 60. The first, second, and third displays 20, 30, 60 may have corresponding maximum lateral dimension dl. In some embodiments, at least one of the first and second displays 20, 30 has the maximum lateral dimension dl of at least 15 centimeters (cm). In some embodiments, at least one of the first and second displays 20, 30 has the maximum lateral dimension dl of at least 20 cm, at least 25 cm, at least 30 cm, at least 35 cm, at least 40 cm, or at least 50 cm. In some embodiments, the third display 60 is smaller than each of the first and second displays 20, 30.

[0080] In some embodiments, the first and second displays 20, 30 have substantially a same size. However, in some other embodiments, the first and second displays 20, 30 have different sizes. In some embodiments, the third display 60 is smaller than each of the first and second displays 20, 30. In some embodiments, the first and second displays 20, 30 have substantially a same shape. However, in some other embodiments, the first and second displays 20, 30 have different shapes.

[0081] FIG. 6 is a detailed sectional view of a reflective polarizer of the HUD 300 shown in FIG. 2, according to an embodiment of the present disclosure. The reflective polarizer may be the first reflective polarizer 10, the second reflective polarizer 13, or the third reflective polarizer 41.

[0082] The reflective polarizer defines mutually orthogonal x, y, and z-axes. The x and y-axes are inplane axes of the reflective polarizer, while the z-axis is a transverse axis disposed along a thickness of the reflective polarizer. In other words, the x and y-axes are disposed along a plane of the reflective polarizer, while the z-axis is perpendicular to the plane of the reflective polarizer.

[0083] In some embodiments, the first reflective polarizer 10 includes a plurality of polymeric layers 14,

[0084] 15. In some embodiments, the plurality of polymeric layers 14, 15 includes a plurality of alternating polymeric first layers 14 and polymeric second layers 15. The plurality of alternating polymeric first and second layers 14, 15 is stacked along a thickness direction of the reflective polarizer (e.g., the first reflective polarizer 10, the second reflective polarizer 13, or the third reflective polarizer 41). In some embodiments, the thickness direction extends substantially along the z-axis. In some embodiments, the polymeric first layers 14 have a different composition than the polymeric second layers 15.

[0085] In some embodiments, the first reflective polarizer 10 includes the plurality of polymeric layers 14, 15 numbering at least 10 in total. In some embodiments, the first reflective polarizer 10 includes the plurality of polymeric layers 14, 15 numbering at least 20, at least 50, at least 75, at least 100, at least 150, at least 200, at least 250, or at least 300 in total.

[0086] In some embodiments, each of the polymeric layers 14, 15 has an average thickness t of less than about 500 nm. The term “the average thickness t”, as used herein, refers to an average of thicknesses measured at multiple points across a plane (i.e., the x-y plane) of each of the plurality of polymeric layers 14, 15. In some embodiments, each of the polymeric layers 14, 15 has the average thickness t of less than about 400 nm, less than about 300 nm, or less than about 200 nm.

[0087] In some embodiments, the first reflective polarizer 10 further includes at least one skin layer 16 disposed on the plurality of polymeric layers 14, 15. The at least one skin layer 16 has an average thickness st of greater than about 500 nm. The term “the average thickness st”, as used herein, refers to an average of thicknesses measured at multiple points across a plane (i.e., the x-y plane) of each of the at least one skin layer 16. In some embodiments, the at least one skin layer 16 has the average thickness st of greater than about 750 nm, greater than about 1000 nm, greater than about 1500 nm, or greater than about 2000 nm.

[0088] In the illustrated embodiment of FIG. 6, the at least one skin layer 16 includes a pair of skin layers

[0089] 16, and the plurality of polymeric layers 14, 15 is disposed between the pair of skin layers 16. The at least one skin layer 16 may protect the plurality of polymeric layers 14, 15 and may also provide mechanical stability to the reflective polarizer. In some cases, the at least one skin layer 16 may act as a protective boundary layer (PBL).

[0090] In some embodiments, for a substantially normally incident light 70 having the at least one visible wavelength, the first reflective polarizer 10 reflects at least 40% of the incident light 70 having one of s- and p-polarization states, and transmits at least 40% of the incident light 70 having the other one of the s- and p-polarization states. In some embodiments, for the substantially normally incident light 70 having the at least one visible wavelength, the first reflective polarizer 10 reflects at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 95% of the incident light 70 having the one of the s- and p- polarization states, and transmits at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 95% of the incident light 70 having the other one of the s- and p-polarization states.

[0091] In some embodiments, for the substantially normally incident light 70 having the at least one visible wavelength, the third reflective polarizer 41 reflects at least 40% of the incident light having one of the s- and p-polarization states, and transmits at least 40% of the incident light 70 having the other one of the s- and p-polarization states. In some embodiments, for the substantially normally incident light 70 having the at least one visible wavelength, the third reflective polarizer 41 reflects at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 95% of the incident light 70 having the one of the s- and p- polarization states, and transmits at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 95% of the incident light 70 having the other one of the s- and p-polarization states.

[0092] In some embodiments, the first polarization state may be the s- polarization state and the second polarization state may be the p- polarization state. In some other embodiments, the first polarization state may be the p- polarization state and the second polarization state may be the s- polarization state. In some cases, the s-polarization state may be along the x-axis, and the p-polarization state may be along the y-axis. In some other embodiments, the p-polarization state may be along the x-axis, and the s-polarization state may be along the y-axis.

[0093] Referring to FIGS. 2 and 6, as discussed above, in some embodiments, the component 41 may be the reflector 41. In some embodiments, for the substantially normally incident light 70, each of the first and second polarization states, and each of at least one blue wavelength in a blue wavelength range extending from about 420 nm to about 480 nm, at least one green wavelength in a green wavelength range extending from about 490 nm to about 560 nm, and at least one red wavelength in a red wavelength range extending from about 590 nm to about 670 nm, the reflector 41 reflects at least 40% of the incident light 70 and the absorber 42 absorbs at least 40% of the incident light 70.

[0094] In some embodiments, for the substantially normally incident light 70, each of the first and second polarization states, and each of the at least one blue wavelength, the at least one green wavelength, and the at least one red wavelength, the reflector 41 reflects at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 95% of the incident light 70 and the absorber 42 absorbs at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95% of the incident light 70.

[0095] FIG. 7 is a schematic view of the HUD 300, according to another embodiment of the present disclosure. The HUD 300 is substantially similar to the HUD 300 illustrated in FIG. 2, with like elements designated by like reference characters. The HUD 300 of FIG. 7 additionally includes a polarizing beam assembly 120.

[0096] The polarizing beam assembly 120 includes a fourth reflective polarizer 110. In some embodiments, the polarizing beam assembly 120 further includes first and second polarization rotators llla, 111b. The fourth reflective polarizer 110 is disposed diagonally between the first and second polarization rotators 11 la, 11 lb. Each of the first and second polarization rotators 11 la, 11 lb is configured to rotate a polarization of an incident beam by substantially 90 degrees.

[0097] As shown in FIG. 7, the polarizing beam assembly 120 is disposed between the second display 30 and the first reflective polarizer 10. In some embodiments, the second emitted image light 31 is received and reflected by the first reflective polarizer 10 after it is reflected by the fourth reflective polarizer 110, reflected and its polarization rotated by substantially 90 degrees by the first polarization rotator Illa, transmitted by the fourth reflective polarizer 110, reflected and its polarization rotated by substantially 90 degrees by the second polarization rotator 11 lb, and reflected by the fourth reflective polarizer 110.

[0098] In other words, the polarizing beam assembly 120 receives the second emitted image light 31. The second emitted image light 31 is reflected by the fourth reflective polarizer 110. Further, the second emitted image light reflected from the fourth reflective polarizer 110 is reflected and its polarization rotated by substantially 90 degrees by the first polarization rotator 11 la.

[0099] The reflected second emitted image light from the first polarization rotator Illa is transmitted through the fourth reflective polarizer 110. The transmitted reflected second emitted image light is further reflected and its polarization is again rotated by substantially 90 degrees by the second polarization rotator lllb. The transmitted reflected second emitted image light from the second polarization rotator 111b is incident on the fourth reflective polarizer 110 and is reflected by the fourth reflective polarizer 110 toward the first reflective polarizer 10.

[0100] In some embodiments, each of the first and second polarization rotators Illa, 111b includes a retarder 113a, 113b disposed between a reflector 112a, 112b and the fourth reflective polarizer 110. Specifically, the first polarization rotator Illa includes the retarder 113a disposed between the reflector 112a and the fourth reflective polarizer 110. Further, the second polarization rotator 111b includes the retarder 113b disposed between the reflector 112b and the fourth reflective polarizer 110.

[0101] The polarizing beam assembly 120 may be used to adjust a positioning of the second real image 33 (shown in FIG. 2) generated by the second image 32. Specifically, the polarizing beam assembly 120 may be used to move the second real image 33 farther without changing the position of the second display 30. Therefore, the HUD 300 may be compact.

[0102] FIG. 8 is a schematic view of the HUD 300, according to another embodiment of the present disclosure. The HUD 300 is substantially similar to the HUD 300 illustrated in FIG. 7, with like elements designated by like reference characters. The HUD 300 of FIG. 8 additionally includes a polarization mixing device 150.

[0103] In some embodiments, the polarization mixing device 150 is disposed between the first and second displays 20, 30 and the optical mirror 40, such that the first transmitted and second reflected image lights 24, 34 are received by the polarization mixing device 150 before they are received and reflected by the optical mirror 40. The polarization mixing device 150 is configured to mix the polarizations of the first transmitted and second reflected image lights 24, 34. In some embodiments, the polarization mixing device 150 may be a quarter wave polarization mixing device. In some embodiments, the polarization mixing device 150 may include a birefringent layer, such as a quarter-wave retarding layer.

[0104] Referring to FIGS. 1-8, the HUD 300 may provide a depth perception of the first and second real images 23, 33 or a perception of a three-dimensional single real image by the occupants. Thus, the HUD 300 may provide a more immersive information environment and differentiation between information displayed on the first and second real images 23, 33. This may provide a unique experience in terms of how the occupants may receive and interact with the information. Moreover, the HUD 300 may be used to combine the third virtual image 63 with the first real image 23 and / or the second real image 33.

[0105] Unless otherwise indicated, all numbers expressing feature sizes, amounts, and physical properties used in the specification and claims are to be understood as being modified by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the foregoing specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by those skilled in the art utilizing the teachings disclosed herein.

[0106] Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and / or equivalent implementations can be substituted for the specific embodiments shown and described without departing from the scope of the present disclosure. This application is intended to cover any adaptations or variations of the specific embodiments discussed herein. Therefore, it is intended that this disclosure be limited only by the claims and the equivalents thereof.

Claims

CLAIMS1. A heads up display (HUD) for use in a vehicle, comprising: a first reflective polarizer; different first and second displays disposed on opposite respective first and second major sides of the first reflective polarizer and configured to form and emit respective first and second emitted image lights toward the first reflective polarizer, the first and second emitted image lights having substantially mutually orthogonal first and second polarization states and comprising respective first and second images, the HUD configured to form respective first and second real images of the first and second images for viewing by an eye of a same first occupant of the vehicle, the first reflective polarizer configured to receive and respectively transmit and reflect at least 40% of the first and second emitted image lights as respective first transmitted and second reflected image lights; and an optical mirror configured to receive and reflect at least 10% of the first transmitted and second reflected image lights toward the eye of the same first occupant.

2. The HUD of claim 1, wherein the first and second displays have different sizes.

3. The HUD of claim 1, wherein the first and second displays have different shapes.

4. The HUD of claim 1, wherein at least one of the first and second displays is coupled to a positioner configured to change at least one or more of an axial position, a lateral position, a tilt, and an orientation of the display relative to the optical mirror.

5. The HUD of claim 1, wherein the first and second displays are so positioned and oriented, and the first and second images having intensities and contents, so as to generate a depth perception of the first and second real images by the first occupant.

6. The HUD of claim 1, wherein the first and second displays are so positioned and oriented, the first and second images having intensities and contents, and the first and second real images are so spaced from each other, so as to generate a perception of a three-dimensional single real image by the first occupant.

7. The HUD of claim 1, wherein sizes of the first and second real images are substantially equal to sizes of the respective first and second displays.

8. The HUD of claim 1, wherein the first and second real images are not co -planar.

9. The HUD of claim 1 further comprising:a windshield; and a third display different from the first and second displays and configured to form and emit a third emitted image light toward the windshield, the third emitted image light comprising a third image, the HUD configured to form a third virtual image of the third image for viewing by an eye of a second occupant of the vehicle, the windshield configured to receive and reflect at least 10% of the third emitted image light as a third reflected image light toward the eye of the second occupant.

10. A heads up display (HUD) for use in a vehicle, comprising: a housing having a top side defining an opening; a first reflective polarizer at least partially disposed inside the housing; a second reflective polarizer and an optical mirror at least partially disposed outside the housing on a same optically transmissive substrate; and first, second, and third displays at least partially disposed inside the housing and configured to form and emit respective first, second, and third images, the HUD configured to form respective first real, second real, and third virtual images of the first, second, and third images for viewing by one or more viewers, the first reflective polarizer configured to receive and respectively transmit and reflect at least 40% of the first and second emitted image lights as respective first transmitted and second reflected image lights, the second reflective polarizer configured to receive and reflect at least 40% of the third emitted image light, the optical mirror configured to receive and reflect at least 30% of the first transmitted and second reflected image lights.

Images