HYBRID LENS AND CASTING METHOD

A hybrid lens includes a primary lens element having a pair of opposing optical surfaces and a secondary lens element disposed directly over at least one of the optical surfaces. The primary lens element may include a 3D-printed layer, and the secondary lens element may be over-formed by casting. An electronic component such as a dimming component, a waveguide component, or an eye-tracking component may be integrated into the hybrid lens.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG.1is a schematic cross-sectional view of a hybrid lens according to some embodiments.

FIG.2illustrates of method of manufacturing the hybrid lens ofFIG.1according to some embodiments.

FIG.3is a schematic cross-sectional view of a hybrid lens with an integrated electronic component according to some embodiments.

FIG.4illustrates a method of manufacturing the hybrid lens ofFIG.3according to some embodiments.

FIG.5illustrates a casting method for forming a hybrid plano-concave lens according to some embodiments.

FIG.6illustrates a casting method for forming a hybrid plano-convex lens according to some embodiments.

FIG.7illustrates a method for forming a hybrid lens according to still further embodiments.

FIG.8illustrates a casting method for forming a composite hybrid lens according to certain embodiments.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

A hybrid lens includes a glass lens element and a polymer lens element disposed over the glass lens element. The hybrid lens may have a plano-concave architecture or a plano-convex architecture, for example, and may include a planar glass element and an over-formed polymer lens element having a curved outer surface. In accordance with various embodiments, the polymer lens element may be formed by three-dimensional printing or casting. A polymer lens element may be formed over one or both major surfaces of the glass lens element.

A hybrid lens according to some embodiments includes a plano-concave lens element formed from a high refractive index material and a meniscus lens element formed from a low refractive index material, where the meniscus lens element directly overlies a concave optical surface of the plano-concave lens element. An electronic component such as a dimming component, a waveguide component, or an eye-tracking component may be directly integrated into the hybrid lens.

A further example hybrid lens includes a plano-concave lens element having negative optical power and a meniscus lens element having positive optical power, where the meniscus lens element overlies a concave portion of the plano-concave lens element.

Still further hybrid lenses include a planar lens element and an over-formed lens element having a concave or a convex outer surface. The planar lens element may include a layer of functional glass and the over-formed lens element may include a printed or cast polymer layer.

A method of manufacturing a hybrid lens includes forming a plano-concave lens element including a high refractive index material and forming a meniscus lens element including a low refractive index material over a concave optical surface of the plano-concave lens element. The method may additionally include forming an electronic component and encapsulating the electronic component within the plano-concave lens element while forming the plano-concave lens element.

A further method of manufacturing a hybrid lens includes placing a glass lens element into a mold and casting a polymer lens element over at least one major optical surface of the glass lens element.

The following will provide, with reference toFIGS.1-10, detailed descriptions of methods for optical system manufacture and associated hybrid lens architectures. The discussion associated withFIGS.1-8includes a description of hybrid lens architectures and associated methods of manufacture. The discussion associated withFIGS.9and10relates to exemplary virtual reality and augmented reality devices that may include a hybrid lens as disclosed herein.

Referring toFIG.1, shown is a cross-sectional schematic view of an example hybrid plano-convex lens. Lens100includes a high refractive index plano-concave lens element140and a low refractive index meniscus lens element150overlying the concave optical surface of the plano-concave lens element. The plano-concave lens element140may have negative optical power and the meniscus lens element150may have positive optical power.

A minimum thickness, e.g., a center thickness t1, of the plano-concave lens element140may range from approximately 50 micrometers to approximately 500 micrometers. A maximum thickness, e.g., a center thickness t2, of the meniscus lens element may range from approximately 1 mm to approximately 10 millimeters.

In certain embodiments, the high refractive index material forming the plano-concave lens element140may include an acrylate, a thio acrylate, or a polyurethane methacrylate and may have a refractive index ranging from approximately 1.53 to approximately 1.70. In some embodiments, the low refractive index material forming the meniscus lens element may include a poly(allyl diglycol carbonate), polyurethane methacrylate, epoxy, or polyamide and may have a refractive index ranging from approximately 1.45 to approximately 1.52. An example method of manufacturing hybrid plano-convex lens100is shown inFIG.2.

Referring toFIG.2A, a plano-concave lens element240may be formed over a substrate210. Substrate210may include a glass substrate, for example. In certain embodiments, plano-concave lens element240may be formed by 3D printing. Thereafter, and with reference toFIG.2B, a mold element220may be disposed over the intermediate structure ofFIG.2A, and a suitable resin may be introduced into the mold element220to form a meniscus lens element250overlying the concave optical surface of plano-concave lens element240. In some embodiments, meniscus lens element250may be molded directly over plano-concave lens element240. Referring toFIG.2C, hybrid plano-convex lens200may be removed from the mold element220and separated from the substrate210to form a free-standing lens.

Turning now toFIG.3, shown is a cross-sectional schematic view of an example hybrid plano-convex lens having a co-integrated electronic component. Hybrid lens300includes a high refractive index plano-concave lens element340and a low refractive index meniscus lens element350overlying the concave optical surface of the plano-concave lens element. An electronic component330may be embedded within the high refractive index plano-concave lens element340. In particular embodiments, the electronic component330may have a planar or substantially planar form factor. An example method of manufacturing hybrid plano-convex lens300is shown inFIG.4.

Referring toFIG.4A, an electronic component430may be formed over a substrate410. Thereafter, as shown inFIG.4B, a plano-concave lens element440may be formed over the substrate410and in a manner to encapsulate electronic component430. Plano-concave lens element440may be formed by 3D printing. With reference toFIG.4C, a mold420may be disposed over the structure ofFIG.4B, and a resin may be introduced into the mold420to form a meniscus lens element450overlying the concave optical surface of plano-concave lens element440. In some embodiments, meniscus lens element450may be molded directly over plano-concave lens element440. Referring toFIG.4D, hybrid plano-convex lens400may be separated from the substrate410and removed from the mold420to form a free-standing lens including a co-integrated electronic component430.

Referring toFIG.5, illustrated is a further method for manufacturing a hybrid lens. As shown inFIG.5A, a functional glass element540may be disposed over a substrate510and supported by support elements512. Functional glass element540may include waveguide glass, eye-tracking glass, active dimming glass, or other functional glass. Substrate510may include a portion of a mold, for example, and the method may include casting.

As shown inFIG.5B, side mold elements515and top mold element520may be arranged to encapsulate the functional glass element540. As shown in the illustrated embodiment, an interior surface of the top mold element520may be convex. A suitable resin550may be injected into the mold and directly over the functional glass element540. That is, a resinous layer formed from resin550may be formed over the functional glass element without an intervening adhesion layer. With reference toFIG.5C, following polymerization or curing of the resin, hybrid lens500may be removed from the mold510,515,520and may include a plano-concave architecture.

Referring toFIG.6, illustrated is a still further method for manufacturing a hybrid lens. As shown inFIG.6A, a functional glass element640may be disposed over a substrate610and supported by support elements612. Functional glass element640may include waveguide glass, eye-tracking glass, active dimming glass, or other functional glass. Substrate610may include a portion of a mold, and the method may include casting.

As shown inFIG.6B, side mold elements615and top mold element620may be arranged to encapsulate the functional glass element640. An interior surface of the top mold element620may be concave. A suitable resin650may be injected into the mold and directly over the functional glass element640such that a resinous layer formed from resin650is formed over the functional glass element without an intervening adhesion layer. With reference toFIG.6C, following polymerization or curing of the resin, hybrid lens600may be removed from the mold610,615,620and may include a plano-convex architecture.

Referring toFIG.7, hybrid lens700may include a functional glass element740and a plano-concave lens element750formed directly over the functional glass element740. Referring toFIG.7A, functional glass element740may be supported by a chuck710or other suitable substrate. Resin layer750may be formed directly over the functional glass element740, such as by 3D printing. Additive and/or subtractive processing, such as etching, may be used to form an ultra-thin resin layer750directly over a region of the functional glass element, as shown inFIG.7B. In the illustrated embodiments, a center thickness of the plano-concave lens element700may range from approximately 50 micrometers to approximately 500 micrometers.

Turning toFIG.8, illustrated is a further method for manufacturing a hybrid lens. In the method ofFIG.8, and referring initially toFIG.8A, lower and upper mold elements810,820may be arranged to encapsulate a functional glass element840. A transfer coating860may be formed over the inner surface of one or both of the mold elements.

Referring toFIG.8B, mold elements810,820may encapsulate functional glass element and a suitable resin850may be injected into the mold and directly over the functional glass element840. During the casting process, such as during polymerization or curing of the resin850, transfer coatings860may bond with the resin. Following polymerization or curing of the resin, hybrid lens800may be removed from the mold and may include functional glass element840, an organic (resinous) lens element850bonded directly to the functional glass element840, and a transfer coating860disposed over one or both major surfaces of the organic (resinous) lens element850. In accordance with some embodiments, a transfer coating may include an anti-reflective coating, a polarizing coating, etc. As will be appreciated, the over-molding method depicted inFIG.8may be a low cost and high yield method of manufacturing hybrid lens800.

A hybrid lens, such as a plano-convex lens, includes a high refractive index plano-concave lens element and a low refractive index meniscus lens element overlying the concave surface of the high refractive index plano-concave lens element. Independently, the plano-concave lens element may have negative optical power (e.g., approximately −1.0 D to approximately 0 D, and cylinder up to approximately +1.0 D) and the meniscus lens element may have positive optical power (e.g., approximately +0.5 D to approximately +2.5 D, and cylinder up to approximately +2.0 D). In some embodiments, an optical power of the hybrid plano-convex lens may range from approximately +0.5 D to approximately +1.5 D, with cylinder up to approximately +1.0 D. The plano-concave lens element may be 3D printed and the meniscus lens element may be cast directly over the concave surface of the plano-concave lens element using a suitable resin.

A refractive index of the plano-concave lens element may range from approximately 1.53 to 1.70, for example, whereas a refractive index of the meniscus lens element may be less than the refractive index of the plano-concave lens element and may range from approximately 1.45-1.52. In some embodiments, an optical component such as a dimming component, waveguide component, or eye-tracking component, and the like may be co-integrated into the hybrid lens by initially forming the optical component and encapsulating the optical component with the plano-concave lens element, i.e., during an act of 3D printing. A total thickness of the hybrid plano-convex lens may be less than that of comparative lenses.

Example Embodiments

Example 1: A hybrid lens includes a primary lens element having a pair of opposing optical surfaces, and a secondary lens element disposed directly over at least one of the optical surfaces.

Example 2: The hybrid lens of Example 1, where the primary lens element includes an inorganic layer and the secondary lens element includes an organic layer.

Example 3: The hybrid lens of any of Examples 1 and 2, where the primary lens element includes a 3D-printed layer.

Example 4: The hybrid lens of any of Examples 1-3, where the primary lens element has a first refractive index and the secondary lens element has a second refractive index different than the first refractive index.

Example 5: The hybrid lens of any of Examples 1-3, where the primary lens element includes a layer of functional glass.

Example 6: The hybrid lens of Example 5, where the functional glass includes an electronic component selected from a waveguide, a dimming module, and an eye-tracking module.

Example 7: The hybrid lens of any of Examples 1-6, where the primary lens element includes a layer of functional glass having an over-formed 3D-printed layer.

Example 8: The hybrid lens of any of Examples 1-7, where the secondary lens element is disposed over the pair of opposing optical surfaces.

Example 9: The hybrid lens of any of Examples 1-8, where the secondary lens element fully encapsulates the primary lens element.

Example 10: A method includes forming a primary lens element including a high refractive index material, and forming a secondary lens element including a low refractive index material over an optical surface of the primary lens element.

Example 11: The method of Example 10, further including forming an electronic component and encapsulating the electronic component within the primary lens element while forming the secondary lens element.

Example 12: The method of any of Examples 10 and 11, where forming the primary lens element includes 3D printing.

Example 13: The method of any of Examples 10-12, where forming the secondary lens element includes casting in a mold.

Example 14: The method of Example 13, further including forming a coating over an inner surface of the mold and transferring the coating to an outer surface of the secondary lens element during the casting.

Example 15: A hybrid lens includes a plano-concave lens element including a high refractive index material, and a meniscus lens element including a low refractive index material, where the meniscus lens element directly overlies a concave surface of the plano-concave lens element.

Example 16: The hybrid lens of Example 15, where a minimum thickness of the plano-concave lens element ranges from approximately 50 micrometers to approximately 500 micrometers.

Example 17: The hybrid lens of any of Examples 15 and 16, where a center thickness of the plano-concave lens element ranges from approximately 50 micrometers to approximately 500 micrometers.

Example 18: The hybrid lens of any of Examples 15-17, where a maximum thickness of the hybrid plano-convex lens element ranges from approximately 1 mm to approximately 10 mm.

Example 19: The hybrid lens of any of Examples 15-18, where a center thickness of the meniscus lens element ranges from approximately 500 micrometers to approximately 9 mm.

Example 20: The hybrid lens of any of Examples 15-19, where the high refractive index material has a refractive index ranging from approximately 1.53 to approximately 1.70, and the low refractive index material has a refractive index ranging from approximately 1.45 to approximately 1.52.

Example 21: The hybrid lens of any of Examples 15-20, where the high refractive index material includes a polymer selected from an acrylate, a thio acrylate, and a polyurethane methacrylate.

Example 22: The hybrid lens of any of Examples 15-21, where the low refractive index material includes a polymer selected from poly(allyl diglycol carbonate), polyurethane methacrylate, epoxy, and polyamide.

Example 23: The hybrid lens of any of Examples 15-22, where the plano-concave lens element has negative optical power.

Example 24: The hybrid lens of any of Examples 15-23, where the meniscus lens element has positive optical power.

Example 25: The hybrid lens of any of Examples 15-23, where the meniscus lens element has negative optical power.

Example 26: The hybrid lens of any of Examples 15-25, where an optical power of the hybrid lens ranges from approximately +0.5 D to approximately +1.5 D.

Example 27: The hybrid lens of any of Examples 15-26, further including an electronic component embedded within the plano-concave lens element.

Example 28: The hybrid lens of Example 27, where the electronic component is selected from a waveguide, a dimming module, and an eye-tracking module.

Turning toFIG.9, augmented-reality system900may include an eyewear device902with a frame910configured to hold a left display device915(A) and a right display device915(B) in front of a user's eyes. Display devices915(A) and915(B) may act together or independently to present an image or series of images to a user. While augmented-reality system900includes two displays, embodiments of this disclosure may be implemented in augmented-reality systems with a single NED or more than two NEDs.

In some embodiments, augmented-reality system900may include one or more sensors, such as sensor940. Sensor940may generate measurement signals in response to motion of augmented-reality system900and may be located on substantially any portion of frame910. Sensor940may represent a position sensor, an inertial measurement unit (IMU), a depth camera assembly, a structured light emitter and/or detector, or any combination thereof. In some embodiments, augmented-reality system900may or may not include sensor940or may include more than one sensor. In embodiments in which sensor940includes an IMU, the IMU may generate calibration data based on measurement signals from sensor940. Examples of sensor940may include, without limitation, accelerometers, gyroscopes, magnetometers, other suitable types of sensors that detect motion, sensors used for error correction of the IMU, or some combination thereof.

Augmented-reality system900may also include a microphone array with a plurality of acoustic transducers920(A)-920(J), referred to collectively as acoustic transducers920. Acoustic transducers920may be transducers that detect air pressure variations induced by sound waves. Each acoustic transducer920may be configured to detect sound and convert the detected sound into an electronic format (e.g., an analog or digital format). The microphone array inFIG.9may include, for example, ten acoustic transducers:920(A) and920(B), which may be designed to be placed inside a corresponding ear of the user, acoustic transducers920(C),920(D),920(E),920(F),920(G), and920(H), which may be positioned at various locations on frame910, and/or acoustic transducers920(I) and920(J), which may be positioned on a corresponding neckband905.

In some embodiments, one or more of acoustic transducers920(A)-(F) may be used as output transducers (e.g., speakers). For example, acoustic transducers920(A) and/or920(B) may be earbuds or any other suitable type of headphone or speaker.

The configuration of acoustic transducers920of the microphone array may vary. While augmented-reality system900is shown inFIG.9as having ten acoustic transducers920, the number of acoustic transducers920may be greater or less than ten. In some embodiments, using higher numbers of acoustic transducers920may increase the amount of audio information collected and/or the sensitivity and accuracy of the audio information. In contrast, using a lower number of acoustic transducers920may decrease the computing power required by an associated controller950to process the collected audio information. In addition, the position of each acoustic transducer920of the microphone array may vary. For example, the position of an acoustic transducer920may include a defined position on the user, a defined coordinate on frame910, an orientation associated with each acoustic transducer920, or some combination thereof.

Acoustic transducers920(A) and920(B) may be positioned on different parts of the user's ear, such as behind the pinna, behind the tragus, and/or within the auricle or fossa. Or, there may be additional acoustic transducers920on or surrounding the ear in addition to acoustic transducers920inside the ear canal. Having an acoustic transducer920positioned next to an ear canal of a user may enable the microphone array to collect information on how sounds arrive at the ear canal. By positioning at least two of acoustic transducers920on either side of a user's head (e.g., as binaural microphones), augmented-reality device900may simulate binaural hearing and capture a 3D stereo sound field around about a user's head. In some embodiments, acoustic transducers920(A) and920(B) may be connected to augmented-reality system900via a wired connection930, and in other embodiments acoustic transducers920(A) and920(B) may be connected to augmented-reality system900via a wireless connection (e.g., a Bluetooth connection). In still other embodiments, acoustic transducers920(A) and920(B) may not be used at all in conjunction with augmented-reality system900.

Acoustic transducers920on frame910may be positioned along the length of the temples, across the bridge, above or below display devices915(A) and915(B), or some combination thereof. Acoustic transducers920may be oriented such that the microphone array is able to detect sounds in a wide range of directions surrounding the user wearing the augmented-reality system900. In some embodiments, an optimization process may be performed during manufacturing of augmented-reality system900to determine relative positioning of each acoustic transducer920in the microphone array.

In some examples, augmented-reality system900may include or be connected to an external device (e.g., a paired device), such as neckband905. Neckband905generally represents any type or form of paired device. Thus, the following discussion of neckband905may also apply to various other paired devices, such as charging cases, smart watches, smart phones, wrist bands, other wearable devices, hand-held controllers, tablet computers, laptop computers, other external compute devices, etc.

As shown, neckband905may be coupled to eyewear device902via one or more connectors. The connectors may be wired or wireless and may include electrical and/or non-electrical (e.g., structural) components. In some cases, eyewear device902and neckband905may operate independently without any wired or wireless connection between them. WhileFIG.9illustrates the components of eyewear device902and neckband905in example locations on eyewear device902and neckband905, the components may be located elsewhere and/or distributed differently on eyewear device902and/or neckband905. In some embodiments, the components of eyewear device902and neckband905may be located on one or more additional peripheral devices paired with eyewear device902, neckband905, or some combination thereof.

Neckband905may be communicatively coupled with eyewear device902and/or to other devices. These other devices may provide certain functions (e.g., tracking, localizing, depth mapping, processing, storage, etc.) to augmented-reality system900. In the embodiment ofFIG.9, neckband905may include two acoustic transducers (e.g.,920(I) and920(J)) that are part of the microphone array (or potentially form their own microphone subarray). Neckband905may also include a controller925and a power source935.

Acoustic transducers920(I) and920(J) of neckband905may be configured to detect sound and convert the detected sound into an electronic format (analog or digital). In the embodiment ofFIG.9, acoustic transducers920(I) and920(J) may be positioned on neckband905, thereby increasing the distance between the neckband acoustic transducers920(I) and920(J) and other acoustic transducers920positioned on eyewear device902. In some cases, increasing the distance between acoustic transducers920of the microphone array may improve the accuracy of beamforming performed via the microphone array. For example, if a sound is detected by acoustic transducers920(C) and920(D) and the distance between acoustic transducers920(C) and920(D) is greater than, e.g., the distance between acoustic transducers920(D) and920(E), the determined source location of the detected sound may be more accurate than if the sound had been detected by acoustic transducers920(D) and920(E).

Controller925of neckband905may process information generated by the sensors on neckband905and/or augmented-reality system900. For example, controller925may process information from the microphone array that describes sounds detected by the microphone array. For each detected sound, controller925may perform a direction-of-arrival (DOA) estimation to estimate a direction from which the detected sound arrived at the microphone array. As the microphone array detects sounds, controller925may populate an audio data set with the information. In embodiments in which augmented-reality system900includes an inertial measurement unit, controller925may compute all inertial and spatial calculations from the IMU located on eyewear device902. A connector may convey information between augmented-reality system900and neckband905and between augmented-reality system900and controller925. The information may be in the form of optical data, electrical data, wireless data, or any other transmittable data form. Moving the processing of information generated by augmented-reality system900to neckband905may reduce weight and heat in eyewear device902, making it more comfortable to the user.

Power source935in neckband905may provide power to eyewear device902and/or to neckband905. Power source935may include, without limitation, lithium ion batteries, lithium-polymer batteries, primary lithium batteries, alkaline batteries, or any other form of power storage. In some cases, power source935may be a wired power source. Including power source935on neckband905instead of on eyewear device902may help better distribute the weight and heat generated by power source935.

As noted, some artificial-reality systems may, instead of blending an artificial reality with actual reality, substantially replace one or more of a user's sensory perceptions of the real world with a virtual experience. One example of this type of system is a head-worn display system, such as virtual-reality system1000inFIG.10, that mostly or completely covers a user's field of view. Virtual-reality system1000may include a front rigid body1002and a band1004shaped to fit around a user's head. Virtual-reality system1000may also include output audio transducers1006(A) and1006(B). Furthermore, while not shown inFIG.10, front rigid body1002may include one or more electronic elements, including one or more electronic displays, one or more inertial measurement units (IMUs), one or more tracking emitters or detectors, and/or any other suitable device or system for creating an artificial reality experience.

Artificial-reality systems may also include one or more input and/or output audio transducers. In the examples shown inFIG.10, output audio transducers1006(A) and1006(B) may include voice coil speakers, ribbon speakers, electrostatic speakers, piezoelectric speakers, bone conduction transducers, cartilage conduction transducers, tragus-vibration transducers, and/or any other suitable type or form of audio transducer. Similarly, input audio transducers may include condenser microphones, dynamic microphones, ribbon microphones, and/or any other type or form of input transducer. In some embodiments, a single transducer may be used for both audio input and audio output.

It will be understood that when an element such as a layer or a region is referred to as being formed on, deposited on, or disposed “on” or “over” another element, it may be located directly on at least a portion of the other element, or one or more intervening elements may also be present. In contrast, when an element is referred to as being “directly on” or “directly over” another element, it may be located on at least a portion of the other element, with no intervening elements present.

As used herein, the term “approximately” in reference to a particular numeric value or range of values may, in certain embodiments, mean and include the stated value as well as all values within 10% of the stated value. Thus, by way of example, reference to the numeric value “50” as “approximately 50” may, in certain embodiments, include values equal to 50±5, i.e., values within the range 45 to 55.

As used herein, the term “substantially” in reference to a given parameter, property, or condition may mean and include to a degree that one of ordinary skill in the art would understand that the given parameter, property, or condition is met with a small degree of variance, such as within acceptable manufacturing tolerances. By way of example, depending on the particular parameter, property, or condition that is substantially met, the parameter, property, or condition may be at least approximately 90% met, at least approximately 95% met, or even at least approximately 99% met.

While various features, elements or steps of particular embodiments may be disclosed using the transitional phrase “comprising,” it is to be understood that alternative embodiments, including those that may be described using the transitional phrases “consisting of” or “consisting essentially of,” are implied. Thus, for example, implied alternative embodiments to a lens element that comprises or includes polycarbonate include embodiments where a lens element consists essentially of polycarbonate and embodiments where a lens element consists of polycarbonate.