Heads up display and vehicle

Abstract

A heads up display (HUD) includes a first reflective polarizer and different first and second displays configured to form and emit respective first and second polarized emitted image lights toward the first reflective polarizer. The first and second polarized emitted image lights include respective first and second polarized emitted images. The HUD is configured to form, substantially in a same image plane, respective first and second real images of the first and second polarized images for viewing by an eye. The first reflective polarizer is configured to receive and respectively transmit and reflect at least 40% of the first and second polarized emitted image lights as respective first transmitted and second reflected polarized image lights. The HUD includes an optical mirror configured to receive and reflect at least 10% of the first transmitted and second reflected polarized image lights as respective first and second viewable image lights toward the eye.

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 HUD.

[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 different first and second displays are disposed on opposite respective first and second major sides of the first reflective polarizer and are configured to form and emit respective first and second polarized emitted image lights toward the first reflective polarizer. The first and second polarized emitted image lights have respective substantially mutually orthogonal first and second polarization states and include respective first and second polarized images. The HUD is configured to form, substantially in a same image plane, respective first and second real images of the first and second polarized images for viewing by an eye of one or more occupants of the vehicle. The first reflective polarizer is configured to receive and respectively transmit and reflect at least 40% of the first and second polarized emitted image lights as respective first transmitted and second reflected polarized image lights. The optical mirror is configured to receive and reflect at least 10% of the first transmitted and second reflected polarized image lights as respective first and second viewable image lights toward the eye of the one or more occupants.

[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 partial reflector, different first and second displays, an optical mirror, and a dashboard. The different first and second displays are disposed on opposite respective first and second major sides of the partial reflector and are configured to form and emit respective first and second emitted image lights toward the partial reflector and including respective first and second images. The HUD is configured to form, substantially in a same image plane, respective first and second real images of the first and second images for viewing by an eye of one or more occupants of the vehicle. The partial reflector is configured to receive and respectively transmit and reflect at least 30% 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 as respective first and second viewable image lights toward the eye of the one or more occupants. Each of the first transmitted and second reflected image lights includes substantially equal amounts of mutually orthogonal polarization states. The dashboard includes a top portion facing the optical mirror and defining a dashboard opening. The first and second displays are at least partially disposed inside the dashboard, and the first transmitted and the second reflected image lights exit the dashboard through the dashboard opening before being received and reflected by the optical mirror.

[0010] Brief Description of the Drawings

[0011] 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.

[0012] FIGS. 1A-1B show schematic views of exemplary vehicles;

[0013] FIG. 2 shows a schematic view of a heads up display (HUD), according to an embodiment of the present disclosure;

[0014] FIG. 3 shows a schematic view of the HUD, according to another embodiment of the present disclosure;

[0015] FIG. 4 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] FIG. 5 shows a schematic top view of a display of the HUD, according to an embodiment of the present disclosure;

[0017] FIG. 6 shows a schematic detailed sectional view of a reflective polarizer of the HUD, according to an embodiment of the present disclosure;

[0018] FIG. 7 A shows a first cone angle of a first polarized image, according to an embodiment of the present disclosure;

[0019] FIG. 7B shows a second cone angle of a second polarized image, according to an embodiment of the present disclosure;

[0020] FIG. 8A shows first and second real images on an image plane, according to an embodiment of the present disclosure; and

[0021] FIG. 8B shows respective first and second viewing cones of the first and second real images of FIG. 8A, according to an embodiment of the present disclosure.

[0022] Detailed Description

[0023] 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.

[0024] In the following disclosure, the following definitions are adopted.

[0025] 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.

[0026] 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).

[0027] 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.

[0028] 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.

[0029] 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.

[0030] As used herein, “at least one of A and B” should be understood to mean “only A, only B, or both A and B”.

[0031] 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.

[0032] 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 different first and second displays are disposed on opposite respective first and second major sides of the first reflective polarizer and are configured to form and emit respective first and second polarized emitted image lights toward the first reflective polarizer. The first and second polarized emitted image lights have substantially mutually orthogonal first and second polarization states and include respective first and second polarized images. The HUD is configured to form, substantially in a same image plane, respective first and second real images of the first and second polarized images for viewing by an eye of one or more occupants of the vehicle. The first reflective polarizer is configured to receive and respectively transmit and reflect at least 40% of the first and second polarized emitted image lights as respective first transmitted and second reflected polarized image lights. The optical mirror is configured to receive and reflect at least 10% of the first transmitted and second reflected polarized image lights as respective first and second viewable image lights toward the eye of the one or more occupants.

[0033] Thus, the first and second real images formed substantially in the same image plane are overlaid, whether colinearly or offset from each other. Further, the HUD of the present disclosure may control viewing of the first and second real images for the one or more occupants of the vehicle. The HUD may selectively display the first and second images to the one or more occupants. Thus, the HUD may provide control over privacy of contents of the first and second images when viewed by the one or more occupants.

[0034] The present disclosure further relates to a heads up display (HUD) for use in a vehicle including a partial reflector, different first and second displays, an optical mirror, and a dashboard. The different first and second displays are disposed on opposite respective first and second major sides of the partial reflector and are configured to form and emit respective first and second emitted image lights toward the partial reflector and including respective first and second images. The HUD is configured to form, substantially in a same image plane, respective first and second real images of the first and second images for viewing by an eye of one or more occupants of the vehicle. The partial reflector is configured to receive and respectively transmit and reflect at least 30% 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 as respective first and second viewable image lights toward the eye of the one or more occupants. Each of the first transmitted and second reflected image lights includes substantially equal amounts of mutually orthogonal polarization states. The dashboard includes a top portion facing the optical mirror and defining a dashboard opening. The first and second displays are at least partially disposed inside the dashboard, and the first transmitted and the second reflected image lights exit the dashboard through the dashboard opening before being received and reflected by the optical mirror.

[0035] Each of the first transmitted and second reflected image lights including the substantially equal amounts of mutually orthogonal polarization states may be critical for driver information display (DID) information to be always visible to the one or more occupants (e.g., a driver of the vehicle). In some cases, even when wearing polarized sunglasses, a significant amount of the first and second viewable image lights having each of the mutually orthogonal polarization states must transmitted toward the one or more occupants.

[0036] Further, the first and second displays are so positioned that they cannot be directly seen from normal viewing positions of the one or more occupants of the vehicle.

[0037] 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 one or more occupants. In some embodiments, one of the one or more occupants of the vehicle 310 is a driver 320 of the vehicle 310. In some embodiments, one of the one or more occupants of the vehicle 310 is a passenger 325 of the vehicle 310. In some embodiments, the vehicle 310 is a car as shown in FIG. 1A, a truck 310a, a bus 310b, a train 310c, a ship 310d, a boat 310e, an airplane 3 lOf, or a helicopter 310g as shown in FIG. IB.

[0038] 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.

[0039] The HUD 300 includes a first reflective polarizer 10, different first and second displays 20, 30, and an optical mirror 40.

[0040] The first reflective polarizer 10 includes opposite first and second major sides 11, 12. In the illustrated embodiment of FIG. 2, 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.

[0041] 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.

[0042] 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.

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

[0044] The first and second polarized emitted image lights 21, 31 have respective substantially mutually orthogonal first and second polarization states. In some embodiments, the first polarization state is an s-polarization state, and the second polarization state is a p-polarization state.

[0045] Further, the first and second polarized emitted image lights 21, 31 include respective first and second polarized images 22, 32. Specifically, the first polarized emitted image light 21 has the first polarization state (e.g., the s-polarization state) and includes the first polarized image 22, and the second polarized emitted image light 31 has the second polarization state (e.g., the p-polarization state) and includes the second polarized image 32.

[0046] The first and second polarized images 22, 32 are used to generate respective first and second real images 23, 33. Specifically, the first polarized image 22 is used to generate the first real image 23 and the second polarized emitted image 32 is used to generate the second real image 33. More specifically, the HUD 300 is configured to form, substantially in a same image plane 40a, the respective first and second real images 23, 33 of the first and second polarized emitted images 22, 32 for viewing by an eye 315 of the one or more occupants (e.g., the driver 320 or the passenger 325 as shown in FIG. 1A) of the vehicle 310 (shown in FIG. 1A). In some embodiments, at least one of the first and second real images 23, 33 includes one or more of a letter, a number, a symbol, a logo, a text, an alphanumeric, a movie, and a picture.

[0047] The first reflective polarizer 10 is configured to receive and respectively transmit and reflect at least 40% of the first and second polarized emitted image lights 21, 31 as respective first transmitted and second reflected polarized image lights 24, 34. Specifically, the first reflective polarizer 10 is configured to receive the first polarized emitted image light 21 and transmit at least 40% of the first polarized emitted image light 21 as the first transmitted polarized image light 24. Similarly, the first reflective polarizer 10 is configured to receive the second polarized emitted image light 31 and reflect at least 40%the second polarized emitted image light 31 as the second reflected polarized image light 34.

[0048] 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 polarized emitted image lights 21, 31 as the respective first transmitted and second reflected polarized image lights 24, 34.

[0049] In some embodiments, the optical mirror 40 is disposed on the windshield 50 of the vehicle 310 shown in FIGS. 1A-1B. In some embodiments, the windshield 50 includes the optical mirror 40.

[0050] The optical mirror 40 is configured to receive and reflect at least 10% of the first transmitted and second reflected polarized image lights 24, 34 as respective first and second viewable image lights 25, 35 toward the eye 315 of the one or more occupants (e.g., the driver 320 or the passenger 325 as shown in FIG. 1A).

[0051] 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 polarized image lights 24, 34 as the respective first and second viewable image lights 25, 35 toward the eye 315 of the one or more occupants.

[0052] In some embodiments, each of the first and second viewable image lights 25, 35 is substantially polarized. In some embodiments, the first viewable image light 25 has substantially the first polarization state, and the second viewable image light 35 has substantially the second polarization state.

[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”. 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 nm to about 680 nm.

[0054] In some embodiments, the opaque optical mirror 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.

[0055] In some embodiments, the opaque optical mirror 40 includes a reflector 41 disposed on an absorber 42. In some embodiments, the reflector 41 is disposed between the absorber 42, and the first and second displays 20, 30.

[0056] In some embodiments, the reflector 41 may be a reflective polarizer, and hence, is interchangeably referred to as “the second reflective polarizer 41”. Accordingly, in some embodiments, the optical mirror 40 includes the second reflective polarizer 41.

[0057] 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.

[0058] 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.

[0059] In some embodiments, the vehicle 310 (shown in FIG. 1A) includes a dashboard 80. In some embodiments, the HUD 300 includes the 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. In addition, in some embodiments, the optical mirror 40 is at least partially disposed outside the dashboard 80.

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

[0062] In some embodiments, the first and second displays 20, 30 and the first reflective polarizer 10 are so positioned that they cannot be directly seen from normal viewing positions of the one or more occupants of the vehicle 310.

[0063] In some embodiments, the first transmitted and the second reflected polarized image lights 24, 34 exit the dashboard 80 through the dashboard opening 82 before being received and reflected by the optical mirror 40.

[0064] In some embodiments, the different first and second displays 20, 30 are configured to form and emit respective first and second emitted image lights 21, 31 instead of the respective first and second polarized emitted image lights 21, 31. In such embodiments, the first and second polarized emitted image lights 21, 31 may include substantially equal amounts of mutually orthogonal polarization states (e.g., the first and second polarization states). Therefore, in such cases, a partial reflector 10 may be used instead of the first reflective polarizer 10 in the HUD 300. Hence, in some embodiments, the first reflective polarizer 10 may be interchangeably referred to as “the partial reflector 10”. In such embodiments, the different first and second displays 20, 30 are disposed on the opposite respective first and second major sides 11, 12 of the partial reflector 10. Further, the different first and second displays 20, 30 are configured to form and emit the respective first and second emitted image lights 21, 31 toward the partial reflector 10. The first and second emitted image lights 21, 31 include the respective first and second images 22, 32.

[0065] Further, the partial reflector 10 is configured to receive and respectively transmit and reflect at least 30% of the first and second emitted image lights 21, 31 as respective first transmitted and second reflected image lights 24, 34 instead of the respective first transmitted and second reflected polarized image lights 24, 34.

[0066] Specifically, the partial reflector 10 is configured to receive the first emitted image light 21 and transmit at least 30% of the first emitted image light 21 as the first transmitted image light 24. Similarly, the partial reflector 10 is configured to receive the second emitted image light 31 and reflect at least 30%the second emitted image light 31 as the second reflected image light 34.

[0067] In some embodiments, the partial reflector 10 is configured to receive and respectively transmit and reflect 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 and second emitted image lights 21, 31 as the respective first transmitted and second reflected image lights 24, 34.

[0068] Moreover, the optical mirror 40 is configured to receive and reflect at least 10% of the first transmitted and second reflected image lights 24, 34 as the respective first and second viewable image lights 25, 35 toward the eye 315 of the one or more occupants. Each of the first transmitted and second reflected image lights 24, 34 include substantially equal amounts of the mutually orthogonal polarization states.

[0069] In such 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.

[0070] FIG. 3 shows a schematic view of the HUD 300, according to another embodiment of the present disclosure. The HUD 300 of FIG. 3 is substantially similar to the HUD 300 illustrated in FIG. 2. However, the HUD 300 of FIG. 3 further includes a retarder layer 43 disposed on the optical mirror 40. The optical mirror 40 is configured to substantially de-polarize the first transmitted and second reflected polarized image lights 24, 34, such that each of the first and second viewable image lights 25, 35 includes substantially equal amounts of the mutually orthogonal polarization states (i.e., the first and second polarization states). Specifically, the retarder layer 43 is configured to substantially de-polarize the first transmitted polarized image light 24, such that the first viewable image light 25 includes substantially equal amounts of the mutually orthogonal polarization states, and further configured to substantially de-polarize the second reflected polarized image light 34, such that the second viewable image light 35 includes substantially equal amounts of the mutually orthogonal polarization states. In some embodiments, the retarder layer 43 may be disposed proximal to the dashboard opening 82 and is configured to substantially de-polarize the first transmitted and second reflected polarized image lights 24, 34, such that each of the first and second viewable image lights 25, 35 includes substantially equal amounts of the mutually orthogonal polarization states. In some embodiments, the retarder layer 43 is disposed at an output of the HUD 300. In some embodiments, the retarder layer 43 is disposed at a window of the output of the HUD 300.

[0071] FIG. 4 is a schematic diagram showing a relative placement of the first and second displays 20, 30 of the HUD 300 shown in FIGS. 2-3, according to an embodiment of the present disclosure.

[0072] As shown in FIG. 4, 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.

[0073] In some embodiments, the first and second polarized images 22, 32 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 polarized image 22 is formed and displayed on the first display surface 26 of the first display 20 and the second polarized emitted image 32 is formed and displayed on the second display surface 36 of the second display 30.

[0074] FIG. 5 is a schematic top view of a display, according to an embodiment of the present disclosure.

[0075] The display may be the first display 20 or the second display 30. The first and second displays 20, 30 may have a 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.

[0076] 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.

[0077] In some embodiments, sizes of the first and second real images 23, 33 (as shown in FIG. 2) 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.

[0078] 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.

[0079] FIG. 6 is a schematic detailed sectional view of a reflective polarizer of the HUD 300, according to an embodiment of the present disclosure. The reflective polarizer may be the first reflective polarizer 10 or the second reflective polarizer 41. FIG. 6 also shows a substantially normally incident light 70 incident on the first and / or second reflective polarizer 10, 41. The reflective polarizer 10, 41 defines mutually orthogonal x, y, and z-axes. The x and y-axes are in-plane axes of the reflective polarizer 10, 41, while the z-axis is a transverse axis disposed along a thickness of the reflective polarizer 10, 41. In other words, the x and y-axes are disposed along a plane of the reflective polarizer 10,41, while the z-axis is perpendicular to the plane of the reflective polarizer 10, 41.

[0080] In some embodiments, the first reflective polarizer 10 includes a plurality of polymeric layers 14, 15. In some embodiments, the plurality of polymeric layers 14, 15 includes a plurality of alternating polymeric first and polymeric second layers 14, 15. In some embodiments, the polymeric first layers 14 have a different composition than the polymeric second layers 15.

[0081] In some embodiments, the plurality of polymeric layers 14, 15 numbers at least 10 in total. In some embodiments, the plurality of polymeric layers 14, 15 numbers 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.

[0082] 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.

[0083] 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.

[0084] In the illustrated embodiment of FIG. 6, the at least one skin layer 16 includes a pair of skin layers 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 first reflective polarizer 10. In some cases, the at least one skin layer 16 may act as a protective boundary layer (PBL).

[0085] In some embodiments, the second reflective polarizer 41 may have a similar construction as that of the first reflective polarizer 10.

[0086] In some embodiments, for the substantially normally incident light 70 having at least one visible wavelength in a visible wavelength range extending from about 420 nm to about 680 nm, the first reflective polarizer 10 transmits at least 40% of the incident light 70 having the first polarization state, and reflects at least 40% of the incident light 70 having the second polarization state.

[0087] In some embodiments, for the substantially normally incident light 70 having the at least one visible wavelength in the visible wavelength range, the first reflective polarizer 10 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 first polarization state, and 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 second polarization state.

[0088] In some embodiments, for the substantially normally incident light 70 having the at least one visible wavelength, the second reflective polarizer 41 reflects at least 40% of the incident light 70 having one of the first and second polarization states, and transmits at least 40% of the incident light 70 having the other one of the first and second polarization states.

[0089] In some embodiments, for the substantially normally incident light 70 having the at least one visible wavelength, the second 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 one of the first and second 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 first and second polarization states.

[0090] As discussed above, in some embodiments, the opaque optical mirror 40 (shown in FIGS. 2-3) includes the reflector 41.

[0091] 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 (shown in FIG. 2) absorbs at least 40% of the incident light 70.

[0092] 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 in the blue wavelength range, the at least one green wavelength in the green wavelength range, and the at least one red wavelength in the red wavelength range, 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%, or at least 95% of the incident light 70.

[0093] FIGS. 7A-7B show respective first and second cone angles al, a2 of the first and second polarized images 22, 32, according to an embodiment of the present disclosure.

[0094] In some embodiments, the first and second polarized images 22, 32 propagate with the different respective first and second cone angles al, a2. Specifically, the first polarized image 22 propagates with the first cone angle al and the second polarized image 32 propagates with the second cone angle a2.

[0095] In some embodiments, the first cone angle al is less than the second cone angle a2 by at least 10 degrees. In some embodiments, the first cone angle al is less than the second cone angle a2 by at least 20 degrees, at least 30 degrees, at least 40 degrees, at least 50 degrees, or at least 60 degrees. In some embodiments, the first cone angle al is less than the second cone angle a2 by at least 2 degrees in two mutually orthogonal propagation directions. In some embodiments, the first cone angle al is less than the second cone angle a2 by at least 4 degrees, at least 6 degrees, at least 8 degrees, at least 10 degrees, or at least 12 degrees in the two mutually orthogonal propagation directions.

[0096] Further, in some embodiments, at least one of the first and second displays 20, 30 includes a plurality of micro-light-emitting diodes (micro-LEDs) 28 configured to emit light. As shown in FIG. 7 A, the first display 20 includes the plurality of micro-LEDs 28.

[0097] FIG. 8A shows the first and second real images 23, 33 on the image plane 40a, according to an embodiment of the present disclosure.

[0098] In some embodiments, the image plane 40a defines a viewing area 90 configured to be viewed by the eye 315 (shown in FIGS. 2-3) of the one or more occupants (e.g., the driver 320 or the passenger 325 as shown in FIG. 1A) of the vehicle 310 (shown in FIG. 1A). Each of the first and second real images 23, 33 substantially extends across and covers the viewing area 90. In some embodiments, each of the first and second real images 23, 33 substantially cover the same viewing area 90 configured to be viewed by the eye 315 of the one or more occupants of the vehicle 310.

[0099] FIG. 8A also shows a first article 27 of the first real image 23 and a second article 37 of the second real image 33. As is apparent from FIG. 8A, the first and second articles 27, 37 are displayed in the same viewing area 90 of the image plane 40a.

[0100] FIG. 8B shows respective first and second viewing cones bl, b2 of the first and second real images 23, 33 of FIG. 8A, according to an embodiment of the present disclosure.

[0101] In some embodiments, the first and second real images 23, 33 have the different first and second viewing cones bl, b2. Specifically, the fist real image 23 has the first viewing cone bl and the second real image 33 has the second viewing cone b2, that is different from the first viewing cone bl.

[0102] In some embodiments, an eye 315a of a first viewer of the one or more occupants 320, 325 (e.g., the driver 320 or the passenger 325 as shown in FIG. 1A) of the vehicle 310 (shown in FIG. 1A) is positioned in a first viewing space 330a allowing the first viewer to view both the first and the second real images 23, 33, and an eye 315b of a second viewer of the one or more occupants 320, 325 of the vehicle 310 is positioned in a different second viewing space 330b allowing the second viewer to view only one of the first and second real images 23, 33.

[0103] As can be seen from FIG. 8B, the eye 315a of the first viewer of the one or more occupants 320, 325 is positioned in the first viewing region 330a as well as in the second viewing region 330b, such that the eye 315a is able to view the first and second real images 23, 33, while the eye 315b of the second viewer of the one or more occupants 320, 325 is positioned in the second viewing region 330b, such that the eye 315b is able to view the second real image 33.

[0104] Referring to FIGS. 2-8B, as the first reflective polarizer 10 transmits and reflects at least 40% of the first and second polarized image lights 21 , 31 , the HUD 300 may display the first and second real images 23, 33 on the same image plane 40a. Further, as the first and second polarized images 22, 32 propagate with the different respective first and second cone angles al, a2, and the first and second real images 23, 33 have the respective first and second viewing cones bl, b2, the HUD 300 may provide privacy to at least one of the one or more occupants. The HUD 300 may display the first and second real images 23, 33, such that at least one of the first and second real images 23, 33 may be visible to one of the one or more occupants 320, 325, and both the first and second real images 23, 33 may be visible to another of the one or more occupants 320, 325. Hence, the HUD 300 may provide selective or complete privacy for at least one of the first and second real images 23, 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 polarized emitted image lights toward the first reflective polarizer, the first and second polarized emitted image lights having respective substantially mutually orthogonal first and second polarization states and comprising respective first and second polarized images, the HUD configured to form, substantially in a same image plane, respective first and second real images of the first and second polarized images for viewing by an eye of one or more occupants of the vehicle, the first reflective polarizer configured to receive and respectively transmit and reflect at least 40% of the first and second polarized emitted image lights as respective first transmitted and second reflected polarized image lights; and an optical mirror configured to receive and reflect at least 10% of the first transmitted and second reflected polarized image lights as respective first and second viewable image lights toward the eye of the one or more occupants.

2. The HUD of claim 1, wherein for a substantially normally incident light having at least one visible wavelength in a visible wavelength range extending from about 420 nm to about 680 nm, the first reflective polarizer transmits at least 40% of the incident light having the first polarization state, and reflects at least 40% of the incident light having the second polarization state.

3. 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.

4. The HUD of claim 1, wherein the first and second polarized images are formed and displayed on respective first and second display surfaces of the respective first and second displays, and wherein the first and second display surfaces make an oblique angle therebetween.

5. The HUD of claim 1, wherein the optical mirror is at least a partially opaque optical mirror having an optical transmittance of less than about 30% for at least one visible wavelength in a visible wavelength range extending from about 420 nm to about 680 nm.

6. The HUD of claim 5, wherein the opaque optical mirror comprises a reflector disposed on an absorber, such that for a substantially normally incident light, each of the first and second polarizationstates, 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 reflects at least 40% of the incident light and the absorber absorbs at least 40% of the incident light.

7. A vehicle comprising the HUD of claim 1.

8. The vehicle of claim 7, wherein the first and second displays are at least partially disposed inside a dashboard of the vehicle and the optical mirror is at least partially disposed outside the dashboard, wherein the dashboard comprises a top portion facing the optical mirror and defining a dashboard opening, and wherein the first transmitted and the second reflected polarized image lights exit the dashboard through the dashboard opening before being received and reflected by the optical mirror.

9. The HUD of claim 1, wherein each of the first and second viewable image lights is substantially polarized, wherein the first viewable image light has substantially the first polarization state, and wherein the second viewable image light has substantially the second polarization state.

10. The HUD of claim 1, wherein the first and second displays and the first reflective polarizer are so positioned that they cannot be directly seen from normal viewing positions of the one or more occupants of the vehicle.

11. The HUD of claim 1, wherein the first and second polarized images propagate with different respective first and second cone angles.

12. The HUD of claim 1, wherein the first and second real images have different first and second viewing cones.

13. The HUD of claim 12, wherein the eye of a first viewer of the one or more occupants of the vehicle is positioned in a first viewing space allowing the first viewer to view both the first and the second real images, and wherein the eye of a second viewer of the one or more occupants of the vehicle is positioned in a different second viewing space allowing the second viewer to view only one of the first and second real images.

14. A heads up display (HUD) in a vehicle, comprising: a partial reflector;different first and second displays disposed on opposite respective first and second major sides of the partial reflector and configured to form and emit respective first and second emitted image lights toward the partial reflector and comprising respective first and second images, the HUD configured to form, substantially in a same image plane, respective first and second real images of the first and second images for viewing by an eye of one or more occupants of the vehicle, the partial reflector configured to receive and respectively transmit and reflect at least 30% of the first and second emitted image lights as respective first transmitted and second reflected image lights; an optical mirror configured to receive and reflect at least 10% of the first transmitted and second reflected image lights as respective first and second viewable image lights toward the eye of the one or more occupants, each of the first transmitted and second reflected image lights comprising substantially equal amounts of mutually orthogonal polarization states; and a dashboard comprising a top portion facing the optical mirror and defining a dashboard opening, wherein the first and second displays are at least partially disposed inside the dashboard, and wherein the first transmitted and the second reflected image lights exit the dashboard through the dashboard opening before being received and reflected by the optical mirror.

15. The HUD of claim 14, wherein the image plane defines a viewing area configured to be viewed by the eye of one or more occupants of the vehicle, and wherein each of the first and second real images substantially extends across and covers the viewing area.

Images