Patent Application
20240241385
The present disclosure is generally related to mechanisms to adjust the inter-axial lens distance (IAD) in a virtual reality/augmented reality (VR/AR) headset. More specifically, the present disclosure includes robust and simple mechanisms for adjusting the position of the lenses in VR/AR displays that can withstand fall shock and provide a smooth and precise adjustment.
Mechanisms to adjust inter-axial distance between the main eyepieces in an AR/VR headset tend to be complex and delicate. This results in a low shock resistance threshold, which means that users have to constantly re-adjust the positioning of the eyepieces due to misalignment or backlash after an impact or shock.
In a first embodiment, a linear actuation mechanism includes a first threaded rod rotatably fixed on a frame, an actuator mechanically coupled to the first threaded rod and configured to cause a rotation thereof, a first nut threaded onto the first threaded rod and attached to a first eyecup configured to hold a first optical element for a headset display, and a rail on the frame configured to support the first eyecup as it moves with the first nut.
In a second embodiment, a headset includes a frame, supporting: a display to provide a virtual image generated in an immersive reality application, two optical elements to provide the virtual image to a headset user, and a linear actuation mechanism configured to adjust an inter-axial distance between the two optical elements. The linear actuation mechanism includes an actuator coupled to a mechanical element and configured to cause a motion thereof, a first eyecup configured to support one of the optical elements, the first eyecup coupled to the mechanical element to move in a first direction by a selected distance upon an actuation of the mechanical element, and a second eyecup configured to support another of the optical elements, the second eyecup coupled to the mechanical element to move in a second direction by the selected distance upon the actuation of the mechanical element, wherein the second direction is opposite to the first direction.
In a third embodiment, a method to adjust an inter-axial distance between two eyepieces in a headset, includes identifying a mismatch between an inter-pupil distance of a headset user and the inter-axial distance between the eyepieces, actuating an adjusting mechanism to change the inter-axial distance and to reduce the mismatch between the inter-pupil distance of the headset user and the inter-axial distance between the eyepieces, and storing a configuration of the eyepieces in the headset associated with the inter-axial distance between the eyepieces associated with the headset user.
These and other embodiments will be clear to one of ordinary skill in the art, in view of the following.
In the figures, elements having the same or similar reference numerals are associated with same or similar attributes and features, unless explicitly mentioned otherwise.
In the following detailed description, numerous specific details are set forth to provide a full understanding of the present disclosure. It will be apparent, however, to one ordinarily skilled in the art, that embodiments of the present disclosure may be practiced without some of these specific details. In other instances, well-known structures and techniques have not been shown in detail so as not to obscure the disclosure.
IAD mechanisms for VR/AR headsets have been susceptible to drop tests and have predominantly used a rack and pinion gear system in some way to transfer opposite and opposing motion. However, these approaches are typically complex and delicate, leading to misalignments and necessary readjustments, and often fall short of the desired precision and accuracy to adapt to a user physiognomy.
To resolve the above problem, embodiments as disclosed herein achieve precise opposing motion of the two eyepieces in a VR/AR headset by using a single moving element with multiple hinge points and rails to ensure a linear motion and rugged framework. In addition, some embodiments are capable of being implemented on existing IAD adjustment systems for VR/AR headsets to solve drop test problems. Some embodiments may implement mechanisms as disclosed herein to any component that uses opposing motion of two components with high impact/drop resistance.
In embodiments as disclosed herein, an adjustment range for IAD may vary from about 58 mm to about 72 mm. It is desirable also that the alignment mechanism can sustain at least a 1 m tall drop, and an impact force of up to ten Newton (10 N) or more. It is expected that at least 1200 cycles of operation can occur with no noticeable degradation.
Eyepieces 15 include at least one optical element or lens having an optical axis 101R (for eyepiece 15R) or 101L (for eyepiece 15L), that includes the geometric center of the optical element (hereinafter, collectively referred to as “optical axes 101”). Typically, optical axes 101 are parallel, and separated by an inter-axial distance (IAD) 105. For VR/AR headset 10, it is desirable that the pupils of the user be aligned with optical axes 101 (when the user looks straight ahead at “infinity”), and that IAD 105 be approximately similar to the inter-pupil distance (IPD) for the user. Because of the high variability of IPD from person to person, IAD 105 may be adjusted for each user with a mechanism 100. It is desirable that mechanism 100 be precise (fine tuning), reliable, and rugged, to avoid constant readjustment by the user.
Different embodiments and aspects of mechanism 100 will be illustrated in the following figures.
Some embodiments include a central pinion 230 that engages eyecups 15 via rack prongs 231l (left) and 231r (right) (hereinafter, collectively referred to as “rack prongs 231”) in opposite sides, such that as the pinion rotates, eyecups 15 move equally in opposite directions. Upon rotation, threaded rods 210 move one or two nuts 215l (left,) 215r (right), 215c, or 215 (hereinafter, collectively referred to as “nuts 215”), which are attached to eyecups 15, thus moving eyecups 15 towards or away from each other, as desired.
Mechanisms 200A and 200B include threaded rods 210l and 210r which may be a single shaft having opposite threads on each half, being moved by a single electric motor in the middle (actuator 220A), or a manually activated knob (actuator 220B). Pinion 230 and rack prongs 231 may be optional, and in some embodiments they are used for having an accurate register of the position and displacement of eyecups 15.
Mechanism 200E uses only one threaded rod (210e for eyecup 15L), and a flat shaft or rail 225. As actuator 220B rotates threaded rod 210e, nut 215 moves eyecup 15L. Rack prong 231l pushes pinion 230, which then moves eyecup 15R on rail 225. The use of a single threaded rod 205e for a right eyecup 15R is identical, and the choice is a design consideration that depends on specific applications and device configuration.
Mechanism 200E allows more real estate for other components within a VR/AR headset and allows actuator 220B to be placed along the horizontal direction, rather than vertical. In some embodiments, rod 210e and rail 225 may be part of a single piece that is threaded in the first half portion (e.g., to the left).
Mechanism 200G includes a gear box 225 that reverses the rotation of threaded rod 210l to actuate threaded rod 210r. Accordingly, eyecups 15 move in opposite directions upon activation of actuator 220B. Mechanism 200G enables the use of two right-handed (or left-handed) threaded rods 210.
Slider 310A moves pins 312, which directly displace eyecups 15. Slider 310B moves pins 312, which pass through slots 313 and also a slot 313b for a rail 315b.
An actuator 320 pushes up and down vertical slider 310C, moving eyecups 15 on rail 315-1, accordingly. Actuator 320 may be a screw or a threaded rod fixed on frame 309 that is rotated either manually or via a motor.
Mechanism 400D includes a lever 410D that has a curved shape (“S” shape) with likewise formed slots 413d. The shape of slots 413d enables the sliding of pins 412 without too much friction, avoiding stoppage, jerking, and slacking of the movement of eyecups 15.
Mechanism 400E includes slots 413e that are formed in extended prongs on each of eyecups 15. This reduces the stress on pins 412 and on lever 410, as it rotates to move cups 15.
Gear 530 is configured to be pushed in and out of engagement with racks 531 (e.g., by a spring-loaded mechanism). A spring 550 biases eyecups 15 towards an initial, unperturbed position, to avoid backlash and provide stability and reliability.
The pressurized fluid provides support that helps with impulse/crumple-zone in drop tests. However, it may be desirable to ensure a hermetic seal fluid line 625 to avoid release of air, liquid, or other fluids that may damage surrounding electronics/housing, and hinder the thermal behavior of the AR/VR headset. Activation may occur by pressing a button that automatically moves eyecups 15 in one direction. To move in the opposite direction, the user may manually displace at least one eyepiece 15, letting the pressurized line acquire an equilibrium value at the desired configuration.
Step 702 includes identifying a mismatch between an inter-pupil distance of a headset user and the inter-axial distance between the eyepieces. In some embodiments, step 702 includes determining a position of two pupils, and a gaze direction of the headset user. In some embodiments, step 702 includes determining a displacement of the eyepieces by detecting a rotation of a pinion and rack mechanically coupling two eyecups holding the eyepieces.
Step 704 includes actuating an adjusting mechanism to change the inter-axial distance and to reduce the mismatch between the inter-pupil distance of the headset user and the inter-axial distance between the eyepieces. In some embodiments, the two eyepieces are each held in one of two eyecups, and step 704 includes at least one of: causing a threaded rod rotatably fixed to a frame of the headset and mechanically coupled to the eyecups, to rotate, causing a lever rotatably fixed to the frame of the headset and mechanically coupled to the eyecups, to rotate, causing a vertical fork mechanically coupled to the eyecups, to move vertically, and causing a pressurized fluid line to horizontally push or pull two rods mechanically coupled to the eyecups.
Step 706 includes storing a configuration of the eyepieces in the headset associated with the inter-axial distance between the eyepieces and the headset user.
As used herein, the phrase “at least one of” preceding a series of items, with the terms “and” or “or” to separate any of the items, modifies the list as a whole, rather than each member of the list (e.g., each item). The phrase “at least one of” does not require selection of at least one item; rather, the phrase allows a meaning that includes at least one of any one of the items, and/or at least one of any combination of the items, and/or at least one of each of the items. By way of example, the phrases “at least one of A, B, and C” or “at least one of A, B, or C” each refer to only A, only B, or only C; any combination of A, B, and C; and/or at least one of each of A, B, and C.
The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments. Phrases such as an aspect, the aspect, another aspect, some aspects, one or more aspects, an implementation, the implementation, another implementation, some implementations, one or more implementations, an embodiment, the embodiment, another embodiment, some embodiments, one or more embodiments, a configuration, the configuration, another configuration, some configurations, one or more configurations, the subject technology, the disclosure, the present disclosure, other variations thereof and alike are for convenience and do not imply that a disclosure relating to such phrase(s) is essential to the subject technology or that such disclosure applies to all configurations of the subject technology. A disclosure relating to such phrase(s) may apply to all configurations, or one or more configurations. A disclosure relating to such phrase(s) may provide one or more examples. A phrase such as an aspect or some aspects may refer to one or more aspects and vice versa, and this applies similarly to other foregoing phrases.
A reference to an element in the singular is not intended to mean “one and only one” unless specifically stated, but rather “one or more.” Pronouns in the masculine (e.g., his) include the feminine and neuter gender (e.g., her and its) and vice versa. The term “some” refers to one or more. Underlined and/or italicized headings and subheadings are used for convenience only, do not limit the subject technology, and are not referred to in connection with the interpretation of the description of the subject technology. Relational terms such as first and second and the like may be used to distinguish one entity or action from another without necessarily requiring or implying any actual such relationship or order between such entities or actions. All structural and functional equivalents to the elements of the various configurations described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and intended to be encompassed by the subject technology. Moreover, nothing disclosed herein is intended to be dedicated to the public, regardless of whether such disclosure is explicitly recited in the above description. No claim element is to be construed under the provisions of 35 U.S.C. §112, sixth paragraph, unless the element is expressly recited using the phrase “means for” or, in the case of a method claim, the element is recited using the phrase “step for.”
While this specification contains many specifics, these should not be construed as limitations on the scope of what may be described, but rather as descriptions of particular implementations of the subject matter. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination. Moreover, although features may be described above as acting in certain combinations and even initially described as such, one or more features from a described combination can in some cases be excised from the combination, and the described combination may be directed to a subcombination or variation of a subcombination.
The subject matter of this specification has been described in terms of particular aspects, but other aspects can be implemented and are within the scope of the following claims. For example, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. The actions recited in the claims can be performed in a different order and still achieve desirable results. As one example, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Moreover, the separation of various system components in the aspects described above should not be understood as requiring such separation in all aspects, and it should be understood that the described program components and systems can generally be integrated together in a single software product or packaged into multiple software products.
The title, background, brief description of the drawings, abstract, and drawings are hereby incorporated into the disclosure and are provided as illustrative examples of the disclosure, not as restrictive descriptions. It is submitted with the understanding that they will not be used to limit the scope or meaning of the claims. In addition, in the detailed description, it can be seen that the description provides illustrative examples, and the various features are grouped together in various implementations for the purpose of streamlining the disclosure. The method of disclosure is not to be interpreted as reflecting an intention that the described subject matter requires more features than are expressly recited in each claim. Rather, as the claims reflect, inventive subject matter lies in less than all features of a single disclosed configuration or operation. The claims are hereby incorporated into the detailed description, with each claim standing on its own as a separately described subject matter.
The claims are not intended to be limited to the aspects described herein, but are to be accorded the full scope consistent with the language claims and to encompass all legal equivalents. Notwithstanding, none of the claims are intended to embrace subject matter that fails to satisfy the requirements of the applicable patent law, nor should they be interpreted in such a way.
