Systems and methods for enhancing vision

Abstract

The head-wearable display system includes a target object detection module that receives a plurality of image pixels of a first portion and a second portion of a target object and corresponding depths; a first light emitter that emits a plurality of first-eye light signals to display a first-eye virtual image of the first portion and the second portion of the target object for a viewer; a first light redirector that respectively changes the light direction of each of the plurality of first-eye light signals emitted from the first light emitter; a first collimator; and a first combiner that redirects and focuses the plurality of first-eye light signals to the first eye of the viewer. The first-eye virtual image of the first portion of the target object in the first field of view has a greater number of the plurality of first-eye light signals per degree than the first-eye virtual image of the second portion of the target object in the second field of view.

Description

[Technical field]

[0001] Related Applications This application claims priority to U.S. Provisional Patent Application No. 63 / 147,214, entitled “AR / VR SYSTEM AND METHOD FOR IMPROVING VISUAL CAPABILITY,” filed February 8, 2021, and U.S. Provisional Patent Application No. 63 / 217,297, entitled “SYSTEM AND METHOD FOR IMPROVING VISUAL ACUITY IN AR / VR ENVIRONMENT,” filed July 1, 2021.

[0002] Additionally, PCT International Application PCT / US21 / 52750, entitled "VIRTUAL IMAGE DISPLAY SYSTEM FOR VIRTUAL REALITY AND AUGMENTED REALITY DEVICES," filed September 30, 2021, and PCT International Application PCT / US2020 / 059317, entitled "SYSTEM AND METHOD FOR DISPLAYING AN OBJECT WITH DEPTHS," filed November 6, 2020, are hereby incorporated by reference in their entireties.

[0003] The present invention relates to systems and methods for enhancing visual acuity; more particularly, to systems and methods that can provide machine-assisted visual acuity of greater than 1.0 in virtual images having multiple objects. [Background technology]

[0004] Visual ability is often limited by the anatomy of the human eye. In particular, parameters such as the refractive diopter of the eye lens, the axial length of the eyeball, and the condition of the cornea and retina greatly affect visual ability. There is no machine vision available on the general market to achieve higher than normal visual ability. Furthermore, in recent years, machine vision has been developed and adapted to many industrial fields to improve the abilities of people with visual impairments. In particular, machine vision has been applied in the medical field to assist patients with blindness or vision impairment conditions such as glaucoma and myopic maculopathy. For example, pixelated image augmentation can assist patients in vision recovery by increasing the intensity or contrast of the object the patient is looking at. However, this can only partially restore the patient's vision.

[0005] Therefore, there is a need to provide a head-wearable display device / system that is convenient for everyday use and can partially or substantially replace / enhance natural human vision by providing the user with visual capabilities that exceed normal human vision. Summary of the Invention [Problem to be solved by the invention]

[0006] The idea of ​​the present invention is to use light signal scanning based light emitting devices in head wearable display systems / devices (e.g. AR glasses or VR goggles, etc.) or retina scanning devices to help people with no visual ability or visual impairment to return to normal life. In particular, the present invention can capture real-time image information of a target object to be seen by a viewer or the environment surrounding the viewer, and reproduce a three-dimensional digital (or pixelated) image that gives the viewer depth perception. Furthermore, the present invention can provide vision correction for people with myopia or farsightedness, etc., instead of traditional prescription glasses. The present invention can also improve vision and exceed the normal visual ability of healthy people. [Means for solving the problem]

[0007] The head wearable display system includes a target object detection module, a first light emitter, a first light redirector, a first collimator, and a first combiner. The target object detection module receives a plurality of image pixels of a first portion and a second portion of the target object. The target object may be an environment surrounding a viewer, a part of an environment surrounding a viewer, or an object in an environment surrounding a viewer, etc. The first light emitter emits a plurality of first eye light signals associated with the target object. For example, the plurality of first eye light signals can directly reproduce the image pixels of the target object such that a viewer can see a virtual image of the first eye of the target object via the head wearable display system. The first light emitter may be capable of generating light pulses to create a pixelated image. In some examples, the light emitter may include a red laser diode, a green laser diode, and a blue laser diode. The first light redirector receives the plurality of first eye light signals emitted by the first light emitter and redirects light of the plurality of first eye light signals emitted from the first light emitter. The direction of light can be changed in multiple spatial dimensions with respect to time such that an image is created through the periodic scanning motion of the first light redirector to create an image frame in a period of time. The light redirector referred to in this invention may refer to a mechanical or optical element that has the ability to dynamically change the direction of light emitted by the light emitter with respect to time. A first collimator may be provided between the first light emitter and the first light redirector to collimate multiple first eye optical signals from the first light emitter. In another embodiment, the first collimator may be provided between the first light redirector and the first combiner. Furthermore, the first collimator can change the optical path length of the first eye optical signal.

[0008] The first combiner is provided to redirect and focus the multiple first eye optical signals to the first eye of the viewer. In some embodiments, the first combiner receives the multiple first eye optical signals from the first light redirector and directs and focuses the multiple first eye optical signals to the first eye of the viewer. The first light redirector can rotate within an angle range or move within a linear displacement range. The light direction of the multiple first eye optical signals is also changed within a certain range; when the first combiner receives the multiple first eye optical signals from the first light redirector 100, the first combiner directs each first eye optical signal with a different angle of incidence to the first eye of the viewer. The multiple first eye optical signals are directed to the first eye of the viewer at a predetermined range of angles of incidence equal to the maximum FOV generated by the head wearable display system. In some embodiments, the spot size of the first eye's optical signal projected onto the retina can be manipulated via varying the distance between the light redirector and the first collimator.

[0009] In one embodiment, the spot size can be adjusted by varying the projection duration of a single pixel, so that the spot size can be adjusted in real time to meet the Rayleigh criterion for different visual acuity (VA) settings. In some variants of this embodiment, the projection duration can be effectively increased by repeatedly projecting the same pixel or image pixel in different rows or columns of pixels.

[0010] According to one embodiment of the present invention, the speed at which the light redirector redirects can be modified to change the distance between two adjacent projected light signals. In one embodiment of the present invention, the spot size of multiple first eye light signals can be reduced such that there is little or no gap between any two adjacent first eye light signals; thereby eliminating the need to change the swing frequency of the light redirector or the emission frequency of the light emitter.

[0011] In another embodiment of the invention, only a portion of the virtual image frame is projected, with a larger number of light signals per unit angle (eg, per degree) of the FOA.

[0012] In some embodiments, the present invention can be implemented as a head-wearable device for vision correction or vision training. The present invention can be used to correct or improve eye disorders such as, but not limited to, myopia, hyperopia, strabismus, amblyopia, and convergence disorders.

[0013] The present invention can capture real-time image pixels of a target object or its surrounding environment and reproduce an enhanced three-dimensional digital image for a viewer of an AR / VR system. The viewer of the present invention can adjust the image quality to achieve better than normal vision (e.g., 20 / 20 vision or better or VA 1.0 or better). Furthermore, the present invention can replace traditional prescription glasses to help people with visual impairments or provide vision correction for people with myopia or hyperopia. The present invention can be used by medical personnel, military personnel, precision industrial sector, aerospace pilots, law enforcement personnel, first aid personnel, athletes, etc. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a schematic diagram of the Rayleigh Criterion. [Diagram 2] FIG. 1 is a schematic diagram illustrating the variation of spot size at different projection planes. [Diagram 3] 1 is a schematic diagram of a display system according to a first embodiment of the present invention; [Figure 4A] 11A and 11B are schematic diagrams illustrating the effect when the position of the collimator is changed. [Figure 4B] FIG. 13 is another schematic diagram illustrating the effect of changing the position of the collimator. [Figure 5A] FIG. 13 is a schematic diagram illustrating the effect of varying the emission duration on the spot size. [Figure 5B]FIG. 11 is another schematic diagram illustrating the effect of varying emission duration on spot size. [Figure 6] FIG. 1 is a schematic diagram illustrating the effect of varying the spatial separation between adjacent optical signals with respect to the FOV. [Figure 7] 1 is a schematic diagram illustrating an embodiment of varying spatial separation between adjacent optical signals. [Figure 8] FIG. 13 is a schematic diagram illustrating an embodiment of changing the swing frequency of the light redirector to change the VA. [Figure 9] 2 is a schematic diagram of a display system according to another embodiment of the present invention. [Figure 10] 2 is another schematic diagram of a display system according to another embodiment of the present invention. [Figure 11] 2 is another schematic diagram of a display system according to another embodiment of the present invention. [Figure 12] 2 is another schematic diagram of a display system according to another embodiment of the present invention. [Figure 13] 1 is a schematic diagram of one embodiment of an optical assembly according to the present invention. [Figure 14] FIG. 2 is another schematic diagram of an embodiment of an optical assembly according to the present invention. [Figure 15] FIG. 1 is a schematic diagram for describing the application of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] The terms used in the following description are intended to be interpreted in their broadest and most reasonable manner, even when used in conjunction with a detailed description of certain specific embodiments of the technology. Certain terms may even be emphasized below; however, any terms intended to be interpreted in any restrictive manner are specifically defined as such in this detailed description section.

[0016] In one aspect, the present invention aims to increase the visual acuity of a human being beyond the normal visual capabilities (supervision) of a healthy person. In another aspect, the present invention provides improved vision for people with visual impairments such as myopia or astigmatism, or contributes to training the impaired eye to improve vision. In yet another aspect, the present invention can substantially replace vision for people with blindness or other severe visual impairments. The present invention can serve as an auxiliary device to improve the human visual acuity of the viewer. In some cases, the present invention can partially or almost completely replace the function of the human eye for people with eye impairments. Furthermore, for viewers with eye impairments, the systems and methods of the present invention can bypass damaged or damaged tissues of the eye and provide a clear image to healthy parts of the viewer's retina. The present invention takes into account the axial length of the viewer's eyeball and the condition of the cornea and retina and incorporates them into the design of the present invention; thereby providing the best usability for a variety of users. In addition, the present invention can provide multiple or continuous depth perception so that the viewer can perceive the highest degree of realism. The present invention is capable of receiving multiple image pixels of a near or distant object and reproducing a virtual image of the object at higher visual acuity to a viewer.

[0017] The term "visual acuity" refers to the number of critical gaps that can be distinguished in an arc minute of the field of view (FOV) by a viewer. A common definition of visual acuity (VA) is given by the following formula: acuity = 1 / gap size (min); and 1 minute = 1 / 60 of a degree is given by:

[0018] For visual acuity of 1.0 (or 20 / 20), the viewer's eye must be able to distinguish contrast patterns (e.g., black and white patterns, etc.) within 1 minute of the field of view (FOV). In other words, for visual acuity of 1.0, the viewer's eye must be able to distinguish 60 contrast patterns within 1 degree of the field of view. For example, if the viewer can only distinguish contrast patterns within 2 minutes of the field of view, the visual acuity is 0.5; and if the viewer can only distinguish contrast patterns within 0.5 minutes of the field of view, the visual acuity is 2. The visual acuity described in this invention is related to the number of pixels that are distinguishable / separable to the retina within 1 minute, which is 1 / 60 degrees of the FOV. In other words, to achieve better than normal visual acuity (VA1.0) in a pixelated display system, the goal is to project to the viewer an image of at least a portion of the object with an increased number of distinguishable pixels to the retina per degree of the field of view; or, the goal is to project an image of the object with more than 60 distinguishable optical signals / pixels to the retina per degree of the FOV. The present invention is designed to be able to generate a virtual image of at least a part of an object with a VA greater than 1.0 for a viewer. Thus, in some examples of this application, the goal is to project a virtual image of an object with more than 120 (VA2.0) or 180 (VA3.0) distinguishable light signals / pixels to the retina per degree of FOV with at least a part of such a virtual image. That is, to achieve the best possible visual acuity, the display system must project the maximum possible number of distinguishable / separable pixels per degree of FOV to the retina of the viewer's eye. The spatial separation between two adjacent (nearby) light signals / pixels determines whether they are distinguishable / separable on the retina. The spatial separation between two adjacent (nearby) light signals / pixels on the retina (or other part of the viewer's eye) can be measured by the spatial distance between the centers of any two adjacent light signals / pixels on a cross section of the optical path. Such spatial distance must meet the criteria for two adjacent light signals to be separable.Therefore, in order to project an increased number of separable light signals (distinguishable pixels) onto the retina within one minute of the field of view, the spot size of the light signal / pixel on the retina needs to be controlled, typically made smaller, so as to contain more separable light signals within one minute of the field of view.

[0019] With reference to FIG. 1, regardless of the distance and size of the target object intended to be reproduced in a virtual image for the viewer by the present invention, the virtual image of the target object must be resolved on the viewer's retina. More specifically, the light signals (light pulse signals or light beam signals) that generate the virtual image must meet what is known as the Rayleigh criterion, a specification for the minimum separation between two light signals that can be resolved to be distinguishable / separable. In a pixelated display system, the light signals correspond to the pixels that generate the virtual image. For example, each light signal may comprise a pixel of the virtual image of the target object. Furthermore, each light signal may have a cross-sectional area (also known as a "spot size") that is approximately circular or elliptical when projected onto a cross section of the optical path (e.g., the retina of the viewer's eye). According to the Rayleigh criterion, the spatial distance / separation between the centers of two adjacent light signals must exceed half the maximum diameter of the adjacent light signals (approximately half the spot size) to allow the two light signals to be resolved. Based on the above reasons, to increase the VA, it is desirable to increase the number of optical signals within a unit of the field of view (e.g., per degree), but the separation between two adjacent optical signals must be maintained to satisfy the Rayleigh criterion for two adjacent optical signals to be distinguishable / separable. The number of optical signals per degree of FOV alone (similar to the concept of resolution) does not need to increase the VA to the viewer. The system must also maintain the appropriate spot size of the optical signals and the spatial distance / separation between the centers of two adjacent optical signals to make them distinguishable / separable optical signals.

[0020] The spot size of the optical signal is related to the dispersion angle and the distance between the light emitter and the cross section of the optical path (the projection plane). With reference to FIG. 2, for a constant dispersion angle α throughout the optical path, the larger the distance between the light emitter and the projection plane, the larger the spot size projected onto the projection plane (the spot size on plane 1 is smaller than the spot size on plane 2). Similarly, for a constant light emitter-projection plane distance, the larger the dispersion angle, the larger the spot size. In the present invention, the final dispersion angle of the optical signal entering the eye and the optical path length between the light emitter and the viewer's retina can be modified using several methods, which are described in more detail below.

[0021] To improve vision, pixel density must be high, and any two adjacent optical signals must be "resolved" (distinguishable / separable). Pixel density is the number of optical signals (e.g., pixels) projected onto a unit area and is proportional to the unit angle (e.g., per degree) of the FOV.

[0022] In the present invention, the system and method for improving vision is to increase the number of resolved and separable light signals projected at a unit angle of the FOV (measured in 1 degree) to create a virtual image frame on the retina. In one embodiment of the present invention, the system and method for improving vision can be implemented as a head-wearable display system, such as AR / VR glasses, goggles, and helmets, or other similar commercial or medical devices. In some other examples, the present invention can be applied to other stationary or non-head-wearable display devices. In the following, a head-wearable display system is used for the purpose of describing the embodiment of the present invention; further, the head-wearable display system can provide a pixelated virtual image to the viewer; thus, the light signals projected by the light emitters can correspond to the pixels of the virtual image. However, the present invention is not limited to this embodiment.

[0023] Referring to FIG. 3, the head wearable display system includes a target object detection module 300, a first light emitter 10, a first light redirector 100, a first collimator 1000, and a first combiner 20. The target object detection module 300 receives a plurality of image pixels of a first portion and a second portion of a target object. The target object may be the surrounding environment of a viewer, a part of the surrounding environment, or a specific object in the surrounding environment. The target object detection module 300 may further include a distance detection unit 301 for determining a depth of the target object or at least a part of the target object. To render a three-dimensional virtual image of the target object, the target object detection module 300 may be able to measure a plurality of points on the target object and create a three-dimensional profile of the target object, so that a three-dimensional virtual image of the target object can be generated later.

[0024] The target object detection module is for receiving a plurality of image pixels from various viewing angles. Each target object detection module may be mounted to a receiving position of the frame of the head wearable display device via a mounting structure of the target object detection module, and the receiving position is adjustable. In an embodiment, the target object detection module can be moved via the mounting structure to adjust the receiving position or the viewing angle. The mounting structure may include a hinge connection to adjust the viewing angle of the target object detection module. The target object detection module is electrically connected to the frame via the mounting structure to receive power or transmit data. In some embodiments, the target object detection module may be a camera incorporating a wide-angle lens, a zoom lens, a fisheye lens, or a multi-purpose lens for various applications. In addition, the camera is not limited to an optical camera, but also includes an infrared camera for measuring temperature, a distance imaging sensor for measuring depth (such as a time-of-flight camera), and other physical parameter measurement sensing modules.

[0025] In some embodiments, the target object detection module is rotatable. The target object detection module may include a first target object detection module and a second imaging module. In this embodiment, the target object detection module captures an image of a user or an environment and further processes the image to recognize it.

[0026] The first light emitter 10 emits a plurality of first eye light signals associated with the target object. For example, the plurality of first eye light signals can generate a first eye virtual image of a first portion and a second portion of the target object for a viewer via a head wearable display system. The first light emitter 10 may have the ability to generate light pulses to create a pixelated virtual image. For example, the first light emitter 10 may be a laser emitter capable of emitting a light signal or pixel at a time. As an example, the light emitter may include a red laser diode, a green laser diode, and a blue laser diode. The first light redirector 100 receives the plurality of first eye light signals emitted by the first light emitter 10 and redirects the light of the plurality of first eye light signals. The direction of light may be redirected in multiple spatial dimensions with respect to time such that an image is created via the periodic scanning motion of the first light redirector 100 to create an image frame within a period of time. The light redirector in the present invention may refer to a mechanical or optical element that has the ability to dynamically change the direction of light emitted by the light emitter with respect to time. Examples thereof may be, but are not limited to, one-dimensional, two-dimensional, and three-dimensional microelectromechanical system (MEMS) mirrors. A first collimator 1000 may be provided between the first light emitter 10 and the first light redirector 100 to collimate the multiple first eye optical signals from the first light emitter 10. In another embodiment, the first collimator 1000 may be provided between the first light redirector 100 and the first combiner 20. Furthermore, the first collimator 1000 can adjust the beam waist position of each of the multiple first eye optical signals so that the multiple first eye optical signals are separable from each other.

[0027] The first combiner 20 is provided to redirect and focus a plurality of first eye optical signals to a first eye of a viewer. The first eye may be the right eye or the left eye of the viewer. In some embodiments, the first combiner 20 receives a plurality of first eye optical signals from the first light redirector 100 and redirects and focuses the plurality of first eye optical signals to the first eye 50 of the viewer. More specifically, as an example, the first light redirector 100 can rotate within an angle range or move within a linear displacement range. As a result, the light direction of the plurality of first eye optical signals is also changed within a certain range; when the first combiner 20 receives a plurality of first eye optical signals (each having a different incidence angle) from the first light redirector 100, the first combiner 20 redirects each first eye optical signal having a different incidence angle to the first eye 50 of the viewer. The rotation or linear displacement of the first light redirector 100 is predetermined so that multiple first eye optical signals are redirected to the viewer's first eye 50 at a predetermined range of incidence angles equal to the maximum FOV generated by the head wearable display system.

[0028] In some embodiments of the present invention, the head wearable display system may have a two-axis design for the combiner so that the pitch and roll (rotation angles along the horizontal and vertical directions) of the combiner can be adjusted. Additionally, the X, Y, and Z positions of the combiner can also be adjusted to match the interpupillary distance of an individual viewer. In some other embodiments, the X, Y, and Z positions of the combiner can also be adjusted for an individual viewer.

[0029] 4A-4B, the divergence angle α of each of the first-eye optical signals traveling from the first combiner 20 to the first eye 50 determines the spot size of the optical signal rendered on the viewer's retina. The larger the divergence angle, the larger the spot size and vice versa. According to one embodiment, the spot size of the first-eye optical signal projected on the retina can be modified by changing the distance between the first light redirector 100 and the first collimator 1000. Referring to FIG. 4A-4B, the diagram illustrates how changing the distance between the first light redirector 100 and the first collimator 1000 affects the spot size. The light beam in the diagram represents the optical path of a single first-eye optical signal projected by the first light emitter 10. Throughout the optical path of the first-eye optical signal traveling from the first light emitter 10 to the viewer's first eye 50, the light beam of the first-eye optical signal undergoes several divergence / convergence cycles. The cross-sectional area (equal to spot size) of the light beam changes along different positions of the optical path. In other words, the spot size is different depending on the position of the optical path. By varying the total optical path between the light emitter and the viewer's eye, the cross-sectional area projected on the viewer's retina is altered, thereby varying the spot size. It is clear that the spot size perceived by the viewer's eye may also depend on the specifications of each individual viewer's eye, such as the eye's total diopter power, axial length, retinal condition, etc., and these factors need to be taken into consideration when initial calibration is performed for different users / viewers. In both Figures 4A and 4B, the first eye's optical signal gradually converges after exiting the first combiner 20, but forms a beam waist (where the cross-sectional area of ​​the beam is smallest) at different positions. In Figure 4A, the optical signal diverges after leaving the beam waist before entering the first combiner 20. The optical signal converges again after being reflected by the first combiner 20 before entering the viewer's first eye 50. In Figure 4B, a beam waist is formed between the first combiner 20 and the viewer's first eye 50. As a result, the spot size of the first eye optical signal provided to the viewer's first eye 50 is different in these two figures.In this embodiment, the position of the beam waist can be adjusted by changing the position of the first collimator 1000, so that the spot size of the multiple first-eye optical signals projected to the viewer's first eye 50 (e.g., retina, etc.) is adjusted so that the multiple first-eye optical signals are separable and resolved according to the Rayleigh criterion. In some other examples, the position of the beam waist (and thereby the spot size) can be adjusted by changing the distance between the first light redirector 100 and the first collimator 1000. Obviously, by manipulating the distance between the first light redirector 100 and the first collimator 1000, the most suitable spot size and beam separation can be evaluated and determined for viewers with different eye conditions. In general, the curvature of the collimator and combiner can be customized for each user, since these parameters can also affect the spot size. Furthermore, since the spot sizes in these two figures are different, whether the spatial distance / separation between the centers of two adjacent first-eye optical signals meets the Rayleigh criterion can vary.

[0030] Described below are several ways to modify the number of first-eye optical signals per degree in the viewer's FOV to change the VA perceived by the viewer, including modifying the spot size of the optical signals as well as the spatial separation between adjacent optical signals.

[0031] With reference to Figures 5A and 5B, in one embodiment, the spot size can be adjusted (e.g., by control software) by changing the projection duration of a single pixel. The light emitter generates an image frame by projecting one light signal / pixel of the image at a time; then the light emitter (fixed) changes the position of the projection via the movement of the light redirector (not shown) to generate an image of another pixel in the new position. Thus, shortening the projection duration of the light signal results in a narrower pixel width in the direction of rotation of the light redirector; lengthening the projection duration of the light signal results in a wider pixel width in the direction of rotation of the light redirector. As a result, the spot size can be adjusted in real time to meet the Rayleigh criterion for various VA settings. In some variants of this embodiment, the projection duration can be effectively lengthened by repeatedly projecting the same pixel or image pixel in different rows or columns of pixels. In Figure 5A, the light emission pulse has a longer projection duration compared to Figure 5B. For the same swing frequency of the light redirector between Figures 5A and 5B, a longer projection duration allows the light signal to sweep over a larger area, which increases the spot size for the light signal.

[0032] Considering that by changing the spot size, the gap between each optical signal also changes, it is necessary to deal with increasing or decreasing the distance between each optical signal. In the following, different embodiments for changing the gap between each optical signal are described.

[0033] According to one embodiment of the present invention, the rate at which the light redirector changes direction (i.e., swing frequency) can be modified to change the distance between each projected light signal. As mentioned above, the light redirector in the present invention may be capable of changing the light direction in one axis or two separate axes (e.g., a two-dimensional MEMS mirror). As an example, a two-dimensional MEMS mirror may be capable of deflecting light signals at high speed in both axes to an optical scan angle of up to about 30°. However, the maximum scan angle in one axis (main scan axis) may be larger than the other axis (secondary scan axis). The swing frequency or swing amplitude of the MEMS mirror can be controlled by applying different drive voltages / electromagnetic field frequencies and different drive voltages / electromagnetic field amplitudes to the MEMS mirror, respectively, as is readily known in the art. According to this embodiment, the first light redirector 100 changes the first or second coordinate components of the multiple first eye optical signals with a non-constant swing frequency (or swing rate, which is the speed at which the light redirector rotates or moves relative to a reference). The first or second coordinate component may be an x ​​or y coordinate component in a Cartesian coordinate system, or a θ and φ coordinate component in a polar coordinate system. When the present invention displays an image at a higher VA setting, the spot size of the light signals can be reduced. The swing rate of the first light redirector 100 can be reduced so that each of the adjacent light signals can be projected with a smaller angular displacement, which in turn makes the projected light signals closer to the viewer's retina (see FIG. 6). As a result, the number of projected light signals per unit angle (e.g., per degree) of the FOA increases, increasing the VA perceived by the viewer. The swing angle of the light redirector is constant, and thus a virtual image frame with the same frame size but with a higher light signal density is generated.

[0034] As shown in Figure 6, to accommodate the reduction in swing frequency while maintaining the same frame rate for image projection, the scanning area of ​​the light redirector can be reduced. This in turn reduces the FOV, since the spatial separation between the centers of each of the projected light signals is reduced. However, the reduction in FOV can actually improve the VA.

[0035] As shown in FIG. 7, in one embodiment of the present invention, the spot size of multiple first eye optical signals can be modified so that there is little or no gap between any two adjacent first eye optical signals. When the optical signals are projected onto the cross section of the optical path, a spot area is created. The spot areas of each of the two adjacent optical signals on the cross section of the optical path are approximately adjacent to each other, as shown in FIG. 7. Thereby, there is no need to change the swing frequency of the light redirector or the emission frequency of the light emitter. However, in this embodiment, the maximum VA may be limited because the minimum spot size is limited.

[0036] In order to maintain a sufficient frame rate, in another embodiment of the present invention, only a portion of the virtual image frame is projected with more light signal per unit angle (e.g., per degree) of FOA (which is a higher VA). The idea behind this embodiment is that when a human eye looks at a target object, the visual axis of the eye is directed to the target object, concentrating the image of the target object on the macula of the eye (the most sensitive part of the retina); therefore, the target object appears to be in the central FOV of vision. Compared to the target object in the image, other parts of the image may be projected onto other parts of the retina that are less sensitive to light, and therefore may be less sharp. Based on the above nature of human vision, the present embodiment provides a higher number of light signals per degree of FOV in a central FOV (or first FOV) representing a first portion (being a central portion) of a frame of a virtual image of a target object compared to a peripheral FOV (or second FOV) representing a second portion (being a peripheral portion) of a frame of a virtual image of a target object, so that a user of the present invention can see the central FOV of the target object with a higher pixel density (higher visual acuity); the image in the peripheral FOV of the target object does not need to be as clear as the central FOV, since the human eye cannot perceive a higher quality image in the peripheral FOV anyway. In other words, the first portion of the target object in the first FOV has a higher number of first eye light signals per degree than the virtual image of the second portion of the target object in the second FOV. In one embodiment, the number of light signals (or pixels) projected in the central FOV can be manipulated by changing the swing frequency of the light redirector when the first light emitter 10 is projecting light signals to the central FOV. In addition to varying the swing frequency, the number of projected light signals (or pixels) in the central FOV can be further varied by modifying the projection frequency or projection duration of the light signals, as described above. By implementing these methods, the time it takes the light emitter to generate a frame (frame rate) can be kept faster. The resulting virtual image created by this method will have a non-uniform pixel density.

[0037] As an example, in normal conditions (swing frequency is at default value), the first light emitter 10 and the first light redirector 100 may be capable of forming an image frame composed of a default resolution (e.g., 1280×720 pixels, etc.) within a first spatial range (e.g., 40 degrees horizontally or 22.5 degrees vertically). The spatial range referred to in this disclosure represents a range in both a first coordinate component and a second coordinate component, which can be expressed in two coordinates. In this embodiment, the first spatial range corresponds to the FOV of the first eye 50. The first image frame is divided into two FOVs, a peripheral FOV and a central FOV. The central FOV of the image frame will be provided with a higher number of light signals (higher light signal / pixel density projected onto the retina) per unit angle (e.g., per degree) of the FOV compared to the peripheral FOV. As an example, the central FOV in both coordinate components may be set as 10 degrees of the overall FOV in both coordinate components; the peripheral FOVs on both sides may be set to be 15 degrees of the overall FOV. If the viewer chooses a higher VA setting, the spot size of the light signal in the central FOV may be smaller; meanwhile, the swing rate of the light redirector may be decreased in response to correct the increase in the gap between each light signal. The light signals in the peripheral FOV may be generated with a default spot size at the default swing frequency of the light redirector. As a result, the viewer may perceive that more is not uniform in the central FOV than in the peripheral FOV in the image frame F1. With reference to FIG. 8, the following demonstrates one specific example for changing the pixel density in one coordinate component (e.g., horizontally or vertically). In this example, the overall FOV in one direction may be 40 degrees, the central FOV may be set to be 10 degrees of the central FOV, and the default total resolution to be displayed per frame is 1280×720. If the target VA is 2.0, then the total number of pixels needed for VA=2.0 in the central FOV is: 60×2×10=1200 pixels (where 60 is the number of pixels per degree of FOV required for VA=1.0).

[0038] For the rest of the FOV (the peripheral FOV), the pixel density remains the same as the original pixel density. The total number of pixels in the above directions in the peripheral FOV is 1280×30 / 40=960 pixels VA=960 / 30 / 60=0.53 It is.

[0039] During the formation of the first image frame, the first light redirector 100 continuously rotates and changes the projection direction of the first light emitter 10 to generate the first image frame in a row-by-row or column-by-column manner. In particular, the first light emitter 10 generates the first image frame by projecting the image of one pixel at a time; then the first light redirector 100 redirects the first eye light signal 1000 to generate the image of another pixel at a new location. The new location is often horizontally or vertically right next to the image of the previous pixel. Thus, after a period of time, the first light emitter 10 generates a row of pixel images or a column of pixel images (e.g., 1280×1 or 1×720, etc.). Then the first light redirector 100 changes the direction of the first eye light signal 1000 to the next row or column and continues to generate the second row or second column of pixel images. This process is repeated until a complete image frame is generated (eg, a complete 1280x720 pixel image).

[0040] In some embodiments, at a constant light emitter light projection frequency, the light redirector swing frequency can be reduced to increase pixel density (by reducing the spatial separation between adjacent pixels) in the cross-scan direction of the light redirector. To increase pixel density in the main scan direction, the light emitter light projection frequency can be increased. As an example, the light redirector swing frequency can be reduced by a factor of 2 to increase the number of pixels in the cross-scan direction from 720p to 1440p. The light projection frequency can be increased by a factor of 2 to increase the number of pixels in the main scan direction from 720p to 1440p.

[0041] In another example, it may be beneficial to implement two one-dimensional light redirectors so that the swing frequency of the light redirector in both the horizontal and vertical directions can be varied according to different regions of the FOV. As described above, the swing frequency of the light redirector in the horizontal and vertical directions is varied according to the horizontal and vertical positions. The projection speed can be increased and / or the swing frequency of the light redirector in both the horizontal and vertical directions can be decreased while projecting the image in the central FOV so that a higher density of pixels or image pixels can be projected in the central FOV (which then increases the VA in the central FOV). The projection speed and / or the swing frequency of the light redirector in both directions can return to normal in the peripheral FOV.

[0042] In a variant of the above embodiment, the image in the central FOV may be generated with a higher VA, but the light emitter does not emit any light signals related to the peripheral VA. In particular, in an AR head-wearable display system, only a portion of the target object (e.g., an object at a greater distance) can be selected by the viewer to be displayed with a higher VA; other portions of the target object can be seen by the viewer with natural vision. Thus, only a small portion of the entire FOV needs to be displayed with a higher number of light signals per degree in the FOV, and the remaining FOV is displayed with zero light signals per FOV. Since a smaller FOV needs to be scanned by the light redirector, the frame rate may be kept relatively high.

[0043] As mentioned above, in order to achieve visual acuity that exceeds normal human visual acuity, it is necessary to increase the number of resolved light signals per FOV projected onto the viewer's retina. To achieve this, the following factors are taken into consideration by the present invention: the spot size of the light signals projected onto the viewer's retina; the size of the FOV perceived by the viewer, and the spatial separation between each light signal. In one embodiment of the present invention, the spot size is related to the size of each of the pixels projected onto the retina. If the spot size is too large or the spatial separation between adjacent pixels (e.g., the spatial separation between the centers of adjacent pixels, or the spatial separation between the edges of adjacent pixels, etc.) is too small, the pixels may overlap each other, further causing the pixel or image to be unresolved; on the other hand, if the spot size is too small or the gap between each pixel is too large, the total number of pixels that can be packed within a unit angle of the FOV (or, in turn, within an area of ​​the retina) will decrease. In either case, the VA will decrease. As an example, the following table illustrates the relationship between VA and the above main factors. A laser projector is used as the light emitter in this example. The resolution of the laser projector in the present invention is typically 1280x720 or 1920x1080 pixels. However, the resolution of the light emitter is not limited to these values. The data shown in the table below is based on experimental results.

[0044] [Table 1] According to the above table, to achieve a VA of 1, the number of pixels resolved (meeting the Rayleigh criterion) within 1 degree of the field of view required is 60. If a laser projector capable of providing a resolution of 1280x720p is used, the number of pixels that need to be resolved within a 10.67 degree FOV to achieve a VA of 2.0 is 120. For a VA of 3.0, 180 pixels need to be resolved within a 7.1 degree FOV. For a VA of 4.0, 240 pixels need to be resolved within a 5.33 degree FOV. If a laser projector capable of providing a resolution of 1920x1080p is used, 120 pixels need to be resolved within a 16 degree FOV to achieve a VA of 2.0. For a VA of 4.0, 240 pixels need to be resolved within an 8 degree FOV.

[0045] Furthermore, to achieve VA above normal vision, the appropriate curvature (and thus focal length) of the combiner must be selected to suit different users. Once selected, the distance between the light redirector and the collimator can be adjusted to project the light signal with the appropriate spot size for viewers who can experience the desired VA setting.

[0046] The following describes an exemplary implementation of the present invention. The head wearable display system may be used as a visual aid by a viewer to obtain a higher visual capability (e.g., higher than VA1.0) than normal human vision. The target object detection module 300 captures a number of image pixels of the target object. The image pixels may relate to a part of the target object or the whole target object depending on the physical size of the target object. Since each part of the target object may have a variable position and depth relative to the viewer, the target object detection module 300 determines the distance or corresponding depth of at least a part of the target object. To better understand the present application, assume that there are two objects with the same physical size in the viewer's surroundings, both of which are viewed by the viewer, the one that is farther away from the viewer (more deep) will occupy a smaller portion of the overall FOV compared to the one that is closer to the viewer (less deep). In order to view the object farther away from the viewer with the same detail as the object closer to the viewer, the object farther away from the viewer needs to be displayed with a higher VA (e.g., greater than VA1.0). Therefore, as described above, in order to render virtual images of different parts of a target object with different depths, the dispersion angle of each of the multiple optical signals and the spatial separation between the centers of any two adjacent optical signals that render an image of the target object need to be modified according to the change in depth. Furthermore, the target object referred to in this specification may refer to an individual object in the surrounding environment or the surrounding environment of the viewer. If the target object occupies a relatively large portion of the entire FOV of the viewer, the virtual image of the target object may be divided into multiple FOVs. Depending on the depths of the different parts of the target object, the number of the multiple first eye optical signals per degree in the first field of view containing the first part of the target object may exceed the number of the multiple first eye optical signals per degree in the second field of view containing the second part of the target object. In this embodiment, the first field of view and the second field of view may each represent different parts of the target object.

[0047] In a variant of the above embodiment, the target object detection module 300 captures image pixels of the moving target object when the target object is moving relative to the viewer. The distance detection unit 301 of the target object detection module 300 dynamically determines the distance or depth of the surrounding moving target object. The FOV of the virtual image of the moving target object changes according to the position of the moving target object. The dispersion angle of each of the multiple optical signals and the spatial separation between the centers of any two adjacent optical signals that render the image of the moving target object need to be modified according to the depth of the object to compensate for the change in FOV. As a result, the number of the multiple first eye optical signals per degree in the first field of view of the target object (e.g., when the target object is far away) may exceed the number of the multiple first eye optical signals per degree in the second field of view of the target object (e.g., when the target object is close). In this embodiment, the first field of view and the second field of view can each represent different virtual images of the moving target object at different times.

[0048] Another aspect of the present invention is the ability to generate images of high VA (higher than VA 1.0) object parts or objects with depth perception.

[0049] Referring to FIG. 9, in some embodiments, the present invention includes a first light projector 1, a first light redirector 100, a first collimator 1000, and a first combiner. In addition, the present invention further includes a second light projector 3 including a second collimator 3000 for emitting a plurality of second eye light signals corresponding to a plurality of first eye light signals to display a virtual image of a second eye of a target object, a second collimator 3000 for adjusting a beam waist position of each of the plurality of second eye light signals so that the plurality of second eye light signals are separable from each other, and a second light redirector 300 for changing the light direction of each of the plurality of second eye light signals emitted from the second light projector 3. The present invention further includes a second combiner 40 for redirecting and converging the plurality of second eye light signals to a second eye 60 of a viewer. The second light projector 3, the second collimator 3000, the second light redirector 300, and the second combiner 40 are similar in function as their counterparts. As an example, a plurality of second eye light signals are provided to a left eye of a viewer, and a plurality of first eye light signals are provided to a right eye of the viewer (or vice versa). Each of the plurality of second eye light signals has a corresponding first eye light signal; i.e., the first eye light signal and the corresponding second eye light signal are fused to generate a virtual binocular pixel of a binocular virtual image. Each of the first eye light signal and each of the second eye light signal have respective angles of incidence entering the first eye 50 and the second eye 60. Furthermore, the second light projector 3, the second collimator 3000, the second light redirector 300, and the second combiner 40 can vary the spot size by varying the position of the beam waist of the plurality of second eye light signals and the spatial separation between adjacent second eye light signals similar to their counterparts. The first eye 50 and the second eye 60 perceive the first eye's optical signal and the corresponding second eye's optical signal to generate binocular vision, where the first eye's optical signal and the corresponding second eye's optical signal blend together to form a binocular pixel for the viewer.In particular, in this embodiment, referring to Figs. 10 and 11, a first eye light signal emitted by the first light projector 1 and redirected from the first combiner 20 enters the first eye 50 of the viewer. A corresponding second eye light signal emitted by the second light projector 3 and redirected from the second combiner 20 enters the second eye of the viewer. The first eye light signal and the second eye light signal are perceived by the viewer to display a virtual binocular pixel 72 of the object 70 with a first depth (d1) related to a first angle (θ1) between the light path extensions of the redirected first eye light signal and the redirected second eye light signal. More specifically, the light path extensions of the first eye light signal and the second eye light signal on the opposite sides of the first and second combiners 40 virtually converge at a position P1. When the first angle θ1 between the extensions of the two optical paths of the first eye optical signal and the second eye optical signal increases, the first depth d1 perceived by the viewer decreases; on the other hand, when the first angle θ1 decreases, the first depth d1 perceived by the viewer increases. The first depth d1 of the first virtual binocular pixel 72 is expressed by the following formula:

[0050]

number

[0051] 9-12, while applying the above method of forming image frames, a pixel in a first image frame F1 and a pixel in a corresponding second image frame F2 form a virtual binocular pixel at a first depth related to a first angle between the first eye light signal and the second eye light signal projected to the viewer's eyes. Upon receiving the multiple light signals, the viewer perceives multiple right pixels in the first image frame F1 for objects in a bounded region A due to the extension of the redirected second eye light signal from the combiner. Region A is referred to as the field of view (FOV) for the second eye 50. Similarly, multiple first eye light signals in the second image frame F2 are redirected by the first combiner 20, pass through the center of the left pupil 62, and are finally received by the left retina 64. Upon receiving the redirected first eye light signals, the viewer perceives multiple left pixels for objects in a bounded region B due to the extension of the redirected first eye light signals. Region B is referred to as the field of view (FOV) for the first eye 50. When both right pixels from the first image frame F1 and left pixels from the second image frame F2 are displayed in region C where region A and region B overlap, at least one second eye optical signal displaying one right pixel and a first eye optical signal displaying a corresponding one left pixel are fused together to display a virtual binocular pixel with a certain depth in region C. The depth is related to the angle between the redirected second eye optical signal and the redirected first eye optical signal. Such an angle is also referred to as the convergence angle.

[0052] 9-12, as described above, a plurality of second eye optical signals are generated by the second optical project 3, redirected by the second combiner 40, and then scanned directly onto the right retina to form a right retinal image on the right retina. Similarly, a plurality of first eye optical signals are generated by the first optical project 1, redirected by the first combiner 20, and then scanned onto the left retina to form a left retinal image on the left retina. In one embodiment, the right retinal image has 36 right pixels from the first image frame F1 in a 6×6 array, and the left retinal image also has 36 left pixels from the second image frame F2 in a 6×6 array (FIG. 11). In another embodiment, the right retinal image has 921,600 right pixels from the first image frame F1 in a 1280×720 array, and the left retinal image has 921,600 left pixels from the second image frame F2 in a 1280×720 array. The object display system is configured to generate a plurality of second eye optical signals and a corresponding plurality of first eye optical signals, which respectively form a right retinal image on the right retina and a left retinal image on the left retina. As a result, the viewer perceives a virtual binocular object with a certain depth in the region C due to image fusion. The first second eye optical signal 16 from the second light project 10 is received and reflected by the second combiner 40. The first redirected second eye optical signal 16′ passes through the right pupil 52 and reaches the viewer's right retina to display the right pixel R34. The corresponding first eye light signal 36 from the first light project 1 is received and reflected by the first combiner 20. The first redirected light signal 36' passes through the left pupil 62 and reaches the viewer's left retina to display the left retinal pixel L33. As a result of the image fusion, the viewer perceives a virtual binocular object with multiple depths, which are determined by the angles of the multiple redirected second eye light signals and the corresponding multiple redirected first eye light signals for the same object. The angles between the redirected second eye light signals and the corresponding first eye light signals are determined by the relative horizontal distances of the right pixel and the left pixel.In other words, the greater the depth of a virtual binocular pixel as perceived by the viewer, the smaller the relative horizontal distance in the X-axis between the right and left pixels forming such virtual binocular pixel. For example, the second virtual binocular pixel 74 is perceived by the viewer as having a greater depth (i.e., farther away from the viewer) than the first virtual binocular pixel 72. Thus, on the retinal image, the horizontal distance between the second right pixel and the second left pixel is smaller than the horizontal distance between the first right pixel and the first left pixel.

[0053] In a variation of the above embodiment, a head wearable display system according to the present invention may have a single combiner that covers both of a viewer's eyes. The curvature of the combiner is designed to receive and converge a plurality of first eye optical signals and second eye optical signals and direct them to a first viewer eye 50 and a second viewer eye 60, respectively. Each of the plurality of second eye optical signals has a divergence angle as it travels from the first combiner 20 to the second viewer eye 60.

[0054] In the above-mentioned method, a virtual image of a part of a target object (such as an object in a target object) consisting of a plurality of first-eye optical signals and a second-eye optical signal can be rendered with multiple depths in an AR environment, so that the viewer can see the virtual image most realistically (with depth perception and 3D effect). Furthermore, based on the multiple depths of different points of the part of the surroundings, the virtual image can be superimposed on the real image of the part of the surroundings as a supplement, so that the viewer can see the part of the surroundings with a higher VA. In this embodiment, the video information captured by the unit of the target object detection module 300 can be superimposed on the image seen by the viewer (as mentioned in U.S. Provisional Patent Application No. 63 / 074444, which is incorporated by reference in its entirety herein). In another embodiment, the present invention is implemented as a VR system, and the viewer's vision can be completely dependent on the video information provided by the VR system.

[0055] In the above embodiment, the eye tracking device 302 can determine the fixation position of the viewer's first eye 50 and the viewer's second eye, respectively. The eye tracking device 302 is configured to track at least the position of both the viewer's pupils. In addition, the eye tracking device may be configured to provide more information about the viewer's eyes, including, but not limited to, eye movement, pupil size, gaze angle (viewing angle), and convergence angle of each of the viewer's eyes. Such eye information can be used to determine the fixation position and fixation depth of the viewer as well as the direction and position of projecting the light signal to the virtual object. The eye tracking device may include a first camera that tracks the first eye 50 and a second camera that tracks the second eye 60. In addition to conventional eye tracking cameras, the first camera and the second camera can be constructed by ultra-small micro-electromechanical system (MEMS) technology. The first camera and the second camera can detect and acquire various eye information using infrared emitters and sensors. The eye tracking device 302 may further include an integrated inertial measurement unit (IMU), which is an electronic device that uses a combination of accelerometers, gyroscopes, and possibly magnetometers to measure and report the specific force, angular velocity, and possibly body orientation of the body. The following describes an exemplary implementation of the present invention in which both the first and second eyes of a viewer are provided with light emitters, collimators, light redirectors, and combiners to obtain a visual capability higher than normal human vision (e.g., higher than VA1.0). The eye tracking device 302 determines a fixation position of the viewer to determine a portion of a target object that the viewer is looking at. The target object detection module 300 captures a plurality of image pixels of the target object. The plurality of image pixels may relate to a portion of the target object or the entire target object. Since each portion of the target object may have a variable position and depth relative to the viewer, the target object detection module 300 determines a distance or a corresponding depth of at least a portion of the target object to which the viewer is fixed.As mentioned above, in order to render virtual images of different parts of a target object having different depths, the dispersion angle of each of the multiple light signals and the spatial separation between the centers of any two adjacent light signals that render an image of the object need to be modified according to the change in depth. Furthermore, the target object referred to in this specification may refer to the surrounding environment of a viewer or an individual object in the surrounding environment. If the target object or a part of the target object occupies a relatively large portion of the entire FOV of a viewer, the virtual image of the target object may be divided into multiple FOVs. Depending on the fixed position of the target object, the number of the multiple first eye optical signals per degree in the first field of view having the first portion of the target object (also the number of the multiple first eye optical signals per degree) may exceed the number of the multiple first eye optical signals per degree in the second field of view having the second portion of the target object; while the number of the multiple second eye optical signals per degree in the third field of view having the first portion of the target object (also the number of the multiple second eye optical signals per degree) may exceed the number of the multiple second eye optical signals per degree in the fourth field of view having the second portion of the target object. The first field of view of the first eye corresponds to the third field of view of the second eye, both of which render the first portion of the target object. The second field of view of the first eye corresponds to the fourth field of view of the second eye, both of which render the second portion of the target object. In this embodiment, the spot size and spatial separation of the multiple first eye optical signals and the multiple second eye optical signals are dynamically modified according to the position fixation of the viewer.

[0056] The dispersion angle of each of the above-mentioned multiple light signals and the spatial separation between the centers of any two adjacent light signals that render an image of the target object can be modified according to the above-mentioned method; namely, by modifying the projection duration of the light emitters, the distance between the combiner and the collimator, the projection frequency of the light emitters, and the swing frequency of the light redirector. In practice, the fixed positions for viewing different objects or different parts of the target object having different three-dimensional positions (including depth) can be constantly changed by both eyes of the viewer. Or, in some cases, both eyes of the viewer may be fixed on a moving object, and thus the viewer needs to constantly change the fixed positions. Therefore, the projection duration of the light emitters, the distance between the combiner and the collimator, the projection frequency of the light emitters, and the swing frequency of the light redirector may need to be dynamically modified according to the fixed positions (whereby the depth of the object is fixed by the viewer).

[0057] 13-14, further, in another variant of this embodiment, an optical assembly can be disposed between the light emitter and the collimator described above to change the area of ​​a predetermined cross section of the optical path of the multiple optical signals. Specifically, an optical assembly having a lens may be implemented to change the optical path of the multiple first eye optical signals 1000 from the first light emitter 10 to the first combiner 20 to change the projected area or cross section size (i.e., spot size) of each of the multiple first eye optical signals. For example, referring to FIG. 13, the optical assembly includes lens_1 and lens_2. Lens_1 and lens_2 are convex lenses. The light emitter is originally placed at the focal length of lens_1. When lens_1 is moved to a new position shown as lens_1', the distance between the light emitter and lens_1 is increased; as a result, the amount of light divergence angle from the LBS is increased. Thereby, the projected area or cross section size of each of the multiple first eye optical signals 1000 is also increased, which causes the spot size of the optical signals to be increased. In another embodiment, referring to FIG. 14, the optical assembly includes lens_1, lens_2, and LBS. Lens_1 and lens_2 are convex lenses. The light emitter is placed at the focal length of lens_1, so that the light signal emitted by the light emitter becomes a substantially parallel light signal after passing through lens_1. In this mode, the focal length of lens_2 can be selected to reduce the FOV. As an example, changing the focal length of lens_2 from 50mm to 100mm (and placing the pupil 100mm away from lens_2 at the focal point of lens_2) can reduce the FOV by half. When the present invention is realized in the form of a head-wearable device or AR / VR glasses, lens_2 can be implemented as a combiner. However, in other embodiments, lens_2 can also be implemented as other optical elements.

[0058] In some embodiments, the methods shown in Fig. 13 and Fig. 14 can be implemented simultaneously, without excluding each other, to further improve the FOV. When the present invention is realized in the form of a head-wearable device or AR / VR glasses, Lens_2 can be implemented as a combiner. However, in other embodiments, Lens_2 can also be implemented as other optical elements.

[0059] The present invention can assist viewers with corneal and retinal disorders (e.g., age-related macular degeneration, etc.). For people with normal eye conditions, the best area to receive light is the macula; however, for some people with macular degeneration or other eye diseases, other areas of the eye may be preferred to sense light and receive image pixels. Thus, the present invention can be used to project light signals onto healthy areas of the retina and generate a circumferential image for the viewer to see. Before implementing the present invention, corneal topography and retinal periphery can be used to find the best light path and location for the light signal to be projected onto the viewer's eye. Meanwhile, it is necessary to identify the best angle of incidence to enter the area of ​​the cornea with the least defect and project light onto the part of the retina with the least defect. To achieve this function, the combiner can be designed to have an elliptical concave surface and / or a customized angle of reflection.

[0060] In the present invention, the combiner 210, 410 receives, redirects, and focuses the optical signals generated by the light emitters 10, 30. In one embodiment, the combiner 210, 410 reflects the optical signals, so that the redirected optical signals are on the same side of the combiner 210, 410 as the incident optical signals. In another embodiment, the combiner 210, 410 refracts the optical signals, so that the redirected optical signals are on a different side of the combiner 210, 410 than the incident optical signals. If the combiner 210, 410 also functions as a refractor, the reflectivity of the combiner can vary widely, such as from 20% to 80%, depending in part on the output of the optical signal generator. Those skilled in the art know how to determine the appropriate reflectivity based on the characteristics of the light emitters 10, 30 and the combiner 210, 410. Furthermore, in one embodiment, the combiner 210, 410 is optically transparent to ambient (environmental) light from the opposite side of the incident optical signals. The transparency can vary widely depending on the application. For AR / MR applications, it is desirable for the transparency to be greater than 50%, such as about 75% in one embodiment. In addition to redirecting the optical signals, the combiner 210, 410 can converge the multiple optical signals forming the combiner image so that they can pass through the pupils and reach the retinas of both eyes of the viewer. The combiner 210, 410 can be made of glass or plastic materials like lenses and coated with certain materials such as metals that make them partially transparent and partially reflective. One advantage of using a reflective combiner instead of the prior art waveguides to direct the optical signals to the viewer's eyes is that it eliminates the problem of undesirable diffraction effects such as multiple shadows, color shifts, etc. The combiner 210, 410 can be a holographic combiner, but this is not preferred as diffraction effects can cause multiple shadows and RGB shifts. In some embodiments, it may be desirable to avoid the use of a holographic combiner. To avoid interference with ambient light, the present invention can utilize shutters to substantially reduce ambient light from entering the viewer's eyes. In one embodiment, the shutter may be a mechanical unit for blocking ambient light. In another embodiment, the shutter may be actuated by reducing the transparency of the first and second combiners 210, 410.

[0061] In some embodiments, the present invention can be implemented as a head-wearable device for vision correction or vision training. The present invention can be used to correct or improve eye disorders such as, but not limited to, myopia, hyperopia, strabismus, amblyopia, and convergence disorders. The principle of correcting or improving the above-mentioned disorders is to target the viewer's eyes with more visual stimuli. In other words, providing the appropriate stimuli to the eyes can encourage the improvement of the eye's vision and muscle movements. Referring to FIG. 15, as an example, the present invention can be used to correct the vision of people with myopia or hyperopia. In this embodiment, the head-wearable device with the AR / VR system can capture real-time image pixels of the target object or surrounding environment to be seen by the viewer through the target object detection module 300, and project the pixelated image with depth perception to the viewer. The system of the pixelated image can be focused on the desired position by the above-mentioned method. For example, just as the ciliary muscles are stimulated to adjust the lens of the eye to focus the image precisely on the retina, a pixelated image can be focused correctly just in front of the retina for people with myopia, or just behind the retina for people with hyperopia. Using this method, the eye muscles can be trained.

[0062] The present invention can capture real-time image pixels of a target object or its surrounding environment and reproduce an enhanced three-dimensional digital image for a viewer of an AR / VR system. The viewer of the present invention can adjust the image quality to achieve better than normal vision (e.g., better than 20 / 20 vision or VA1.0). Furthermore, the present invention can help people with visual impairments or replace traditional prescription glasses to provide vision correction for people with myopia or hyperopia. The present invention may be used by medical personnel, military personnel, precision industrial sector, aerospace pilots, law enforcement personnel, emergency and rescue personnel, athletes, etc.

[0063] Although, for purposes of illustration, particular embodiments of the invention have been described in detail, various modifications and enhancements can be made without departing from the spirit and scope of the disclosure.

Claims

1. a target object detection module that receives a plurality of image pixels of a first portion and a second portion of a target object and a corresponding depth; a first light emitter that emits a plurality of first-eye light signals to display a first-eye virtual image of the first portion and the second portion of the target object for a viewer; a first light redirector for respectively redirecting light of each of the plurality of first eye optical signals emitted from the first light emitter; a first collimator disposed between the first light emitter and the first light redirector, the first collimator adjusting a beam waist position of each of the plurality of first eye optical signals by manipulating a distance between the first light redirector and the first collimator such that the plurality of first eye optical signals are separable from each other; a first combiner for redirecting and focusing the plurality of first eye optical signals to a first eye of the viewer; A head wearable display system comprising: a first-eye virtual image of a first portion of the target object in a first field of view has a greater number of the plurality of first-eye optical signals per degree than a first-eye virtual image of a second portion of the target object in a second field of view; A head wearable display system, wherein a number of the plurality of first eye optical signals per degree for a first eye virtual image of the target object is adjusted based on a corresponding depth of the target object.

2. 2. The head wearable display system of claim 1, wherein the multiple first eye optical signals are separable from each other if the spatial distance between the centers of any two adjacent first eye optical signals on a cross section of the optical path is greater than half the maximum diameter of the two adjacent first eye optical signals.

3. The head wearable display system of claim 1 , wherein the number of the multiple first eye optical signals per degree for a first eye virtual image of a first portion of a target object in the first field of view exceeds 120.

4. 2. The head wearable display system of claim 1, further comprising: varying a projection duration of the first light emitter for each of the plurality of first eye optical signals to modify a spot size of the plurality of first eye optical signals relative to a first eye virtual image of a first portion of the target object.

5. The head wearable display system of claim 1 , wherein the projection frequency of the first eye light emitter is changed to modify the number of first eye light signals per degree for the first eye virtual image of the first portion of the target object.

6. The head wearable display system of claim 1 , wherein the swing frequency of the first light redirector is changed to modify the number of first eye light signals per degree for the first eye virtual image of the first portion of the target object.

7. The head wearable display system of claim 1 , wherein the spot areas of each of two adjacent first eye optical signals on a cross section of the optical path are approximately adjacent to each other.

8. The head wearable display system of claim 1 , wherein the first light emitter includes a red laser diode, a green laser diode, and a blue laser diode.

9. The head wearable display system of claim 6 , wherein the light direction of the plurality of first eye light signals is varied at the swing frequency with respect to time to display the virtual image of the first eye of the target object, the swing frequency being non-constant.

10. the light direction includes a first coordinate component and a second coordinate component; 10. The head wearable display system of claim 9, wherein a first coordinate component and a second coordinate component of the light direction of the first eye light signal are varied at a first swing frequency and a second swing frequency, respectively, with respect to time to display a virtual image of the first eye of the target object, and the first swing frequency or the second swing frequency is non-constant.

11. 10. The head wearable display system of claim 9, wherein each of the plurality of first eye optical signals forms a pixel in the first eye virtual image of the target object, and wherein pixel density in the first eye virtual image is not uniform.

12. 12. The head wearable display system of claim 11, wherein a first portion of the target object is a central portion and a second portion of the target object is a peripheral portion, and a first-eye virtual image of the first portion of the target object has a higher pixel density than a first-eye virtual image of the second portion of the target object.

13. a second light emitter that emits a plurality of second eye light signals corresponding to the plurality of first eye light signals to display a second eye virtual image of the first portion and the second portion of the target object for the viewer; a second light redirector for respectively redirecting light of each of the plurality of second eye optical signals emitted from the second light emitter; a second collimator disposed between the second light emitter and the second light redirector, for adjusting a beam waist position of each of the plurality of second eye optical signals such that the plurality of second eye optical signals are separable from one another; and Further comprising: the first combiner receives and focuses the plurality of second eye optical signals toward a second eye of the viewer; a second-eye virtual image of the first portion of the target object in a third field of view has a greater number of second-eye optical signals per degree than a second-eye virtual image of the second portion of the target object in a fourth field of view; 2. The head wearable display system of claim 1, wherein a first eye optical signal and a corresponding second eye optical signal are perceived by the viewer to display virtual binocular pixels of a binocular virtual image of the target object having a depth related to the angle between the first eye optical signal and the corresponding second eye optical signal projected to the viewer's eyes.

14. a second light emitter that emits a plurality of second eye light signals corresponding to the plurality of first eye light signals to display a second eye virtual image of the first portion and the second portion of the target object for the viewer; a second light redirector for respectively redirecting light of each of the plurality of second eye optical signals emitted from the second light emitter; a second collimator disposed between the second light emitter and the second light redirector, for adjusting a beam waist position of each of the plurality of second eye optical signals such that the plurality of second eye optical signals are separable from one another; and a second combiner for redirecting and focusing the plurality of second eye optical signals to a second eye of the viewer; Further comprising: a second-eye virtual image of the first portion of the target object in a third field of view has a greater number of second-eye optical signals per degree than a second-eye virtual image of the second portion of the target object in a fourth field of view; 2. The head wearable display system of claim 1, wherein a first eye optical signal and a corresponding second eye optical signal are perceived by the viewer to display virtual binocular pixels of a binocular virtual image of the target object having a depth related to the angle between the first eye optical signal and the corresponding second eye optical signal projected to the viewer's eyes.

15. The head wearable display system of claim 14 , further comprising an eye tracking device for determining the visual axes of the viewer's first eye and the viewer's second eye, respectively, to determine a fixation position.

16. The head wearable display system of claim 14 , wherein the target object detection module determines three-dimensional coordinates for each of a plurality of image pixels of the first and second portions of the target object.

17. The head wearable display system of claim 14 , wherein a binocular virtual image of the target object is displayed superimposed on the target object.

18. The head wearable display system of claim 14 , further comprising a shutter that substantially reduces ambient light from entering the viewer's eye.

19. The head wearable display system of claim 18 , wherein the shutter is actuated by reducing the transparency of the first combiner and the second combiner.

20. The head wearable display system of claim 15, wherein the projection frequency of the first light emitter and the projection frequency of the second light emitter are changed in response to the fixed position to respectively modify the number of first eye optical signals per degree for a first eye virtual image of the first portion of the target object and the number of second eye optical signals per degree for a second eye virtual image of the first portion of the target object.

21. The head wearable display system of claim 15, wherein the swing frequency of the first light redirector and the swing frequency of the second light redirector are changed in response to the fixed position to respectively modify the number of first eye light signals per degree for a first eye virtual image of the first portion of the target object and the number of second eye light signals per degree for a second eye virtual image of the first portion of the target object.

22. The head wearable display system of claim 15, wherein the projection frequency of the first light emitter and the projection frequency of the second light emitter are changed in response to the fixed position to respectively modify the number of first eye optical signals per degree for a first eye virtual image of the first portion of the target object and the number of second eye optical signals per degree for a second eye virtual image of the first portion of the target object.

23. The head wearable display system of claim 15, further comprising: varying a projection duration of the first light emitter for each of the plurality of first eye optical signals and a projection duration of the second light emitter for each of the plurality of second eye optical signals in response to the fixed position to respectively modify a spot size of the plurality of first eye optical signals for a first eye virtual image of the first portion of the target object and a spot size of the plurality of second eye optical signals for a second eye virtual image of the first portion of the target object.

24. 16. The head wearable display system of claim 15, wherein a first distance between the first light redirector and the first collimator and a second distance between the second light redirector and the second collimator are changed in response to the fixed position to respectively modify spot sizes of a plurality of first eye optical signals for a first eye virtual image of the first portion of the target object and spot sizes of a plurality of second eye optical signals for a second eye virtual image of the first portion of the target object.

Images