Abstract: A head-mounted computing device having a waveguide optical engine assembly is disclosed. The waveguide is enclosed in a housing to limit or minimize exposure of the waveguide to ambient light. Further, the waveguide optical engine assembly comprises a compact footprint by allowing the other components of the waveguide optical engine assembly, such as a microprojector, a prism assembly, and the like, to be placed behind a rear surface of the waveguide. In addition to the compact footprint of the waveguide optical assembly, the configuration of the waveguide optical assembly disclosed, allows for maximization of advantages provided by the waveguide as related to eye box and eye relief. Additionally, the power requirements of the waveguide are greatly reduced, which also results in a prolonged battery life powering the head-mounted computing device.

Abstract: A projection system includes a first optical system and a second optical system including an optical element and a reflector and disposed at the enlargement side of the first optical system. The optical element has a reflection surface, a first transmissive surface disposed at the enlargement side of the reflection surface, and a second transmissive surface disposed at the enlargement side of the first transmissive surface. The reflector is disposed at the enlargement side of the reflection surface and at the reduction side of the first transmissive surface. The reflector is disposed between the optical element and the first optical system in the direction along a first optical axis of the first optical system.

Abstract: A head-mounted computing device having a convertible waveguide optical engine assembly is disclosed. The waveguide in accordance with aspects herein can be utilized in its transparent configuration, or may be provided with means for blocking light from passing through it either by using mechanical means, or by using different types of treatments that can switch the waveguide between opaque an transparent states based on an external stimulus, such as, for example, electricity, temperature, light, and the like. Further, the waveguide optical engine assembly comprises a compact footprint, which is advantageous for head-mounted computing devices. In addition to the compact footprint of the waveguide optical assembly, the configuration of the waveguide optical assembly, as disclosed, allows for maximization of advantages provided by the waveguide as related to eye box and eye relief.

Abstract: An augmented reality and extended reality surgical system. The system may comprise a wearable device, such as a head mounted display or glasses, that provides the user with virtual reality, augmented reality, and/or mixed reality for surgery visualization. This may allow the user to access 2D or 3D imaging, magnification, virtual visualization, six-degrees of freedom (6DoF) image management, and/or other images while still viewing real reality and thus maintaining a presence in the operating room.

Abstract: An optical system and a projection device are provided. The optical system includes a display unit, a first lens group, a second lens group, and a reflector in sequence along a transmission direction of light; both the first lens group and the second lens group have positive focal powers; the optical system satisfies the following relationship: 0.01?|?100|?0.02 and 0.005?|?200|?0.015; ?100 represents a focal power of the first lens group, and ?200 represents a focal power of the second lens group.

Abstract: The present invention relates to a reflective eyepiece optical system and a head-mounted near-to-eye display device. The system includes: a first lens group, and a first optical element and a second lens group for transmitting and reflecting a light from a miniature image displayer; the second lens group includes one optical reflection surface which is an optical surface farthest from a human eye viewing side in the second lens group; the optical reflection surface is concave to a human eye viewing direction; the first optical element reflects the light refracted by the first lens group to the second lens group, and then transmits the light refracted, reflected and then refracted by the second lens group to human eyes; and the focal length combination among respective lenses is negative, positive and positive.

Abstract: The present invention relates to a reflective eyepiece optical system and a head-mounted near-to-eye display device. The system includes: a first optical element and a second optical element arranged successively along an incident direction of an optical axis of the human eye, and a first lens group located on an optical axis of an miniature image displayer. The first optical element reflects the image light refracted by the first lens group to the second optical element, and then transmits the image light reflected by the second optical element to the human eye. The effective focal lengths of the first sub-lens group, the second sub-lens group and the third sub-lens group are a combination of positive, negative and positive. The optical path is effectively folded, the overall size of the optical system is reduced, aberrations are largely eliminated, and a visual experience effect of high liveness is achieved.

Abstract: Described examples include a device having a prism cube having a first side and a second side opposite the first side, the prism cube configured to: receive light comprising a first color light and a second color light, direct the first color light to the first side of the prism cube, and direct the second color light to the second side of the prism cube.

Abstract: A projection optical system includes an eyepiece optical system configured to refract and reflect a light emitted from an image forming unit for forming image information to display a virtual image, wherein the eyepiece optical system includes at least a concave lens, a folding mirror, and a concave mirror which are successively placed in order from the image forming unit including a liquid crystal display panel. The projection optical system configured as above is provided on a head-up display.

Abstract: The present disclosure discloses a projection lens assembly. The projection lens assembly includes, sequentially along an optical axis from an image side to a source side, a first lens, a second lens, a third lens, and a fourth lens. The first lens has a positive refractive power, and an image-side surface of the first lens is a convex surface. The second lens has a positive refractive power or a negative refractive power, and a source-side surface of the second lens is a convex surface. The third lens has a positive refractive power. The fourth lens has a positive refractive power or a negative refractive power.

Abstract: The present disclosure discloses a projection lens assembly. The projection lens assembly includes, sequentially from an image-source side to an image side along an optical axis, a first lens having a positive refractive power; and a second lens having a positive refractive power. At least one of the first lens or the second lens is a glass lens. A total effective focal length f of the projection lens assembly and an effective focal length f2 of the second lens satisfy: 1<f/f2<1.5.

Abstract: A projecting device includes an intermediate optical system arranged along an optical axis and a reflective optical system including a reflecting component and at least one lens. The at least one lens having a first and a second optical surfaces which are opposite is between the reflecting component and the intermediate optical system; the second optical surface faces the intermediate optical system. After piercing the intermediate optical system, the image beam enters the at least one lens through the second optical surface, and enters a reflecting surface of the reflecting component through the first optical surface; after reflected by the reflecting surface, the image beam pierces the at least one lens, leaves the at least one lens from the second optical surface, and is projected toward the imaging plane. The effective diameters of the reflecting component and the at least one lens are on one side of the optical axis.

Abstract: An additive manufacturing system including a two-dimensional energy patterning system for imaging a powder bed is disclosed. Improved optical systems supporting beam combining, beam steering, and both patterned and unpatterned beam recycling and re-use are described.

Abstract: A projection optical system includes a first lens group having negative power and a second and third lens group having positive power, and a first optical path deflector disposed between two lens groups. The first lens group includes three negative lenses. The second lens group includes at least one positive lens. The third lens group includes a plurality of positive lenses. The three negative lenses of the first lens group are each a single lens. The third lens group includes a jointed lens including at least one of the plurality of positive lenses. f is a focal length of the entire project in optical system, d is a length between two lens groups where the first optical path defector is disposed, Dst is a distortion aberration at a reduction-side maximum image height, and the projection optical system satisfies Conditional Expressions (1) and (2) below: 0.4<d/f<12.0??(1) ?45%<Dst<?10%??(2).

Abstract: An optical imaging system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens, disposed in order from an object side to an imaging plane. One or any combination of the first lens to the seventh lens are formed of glass. One or both surfaces of one or more of the first lens to the seventh lens are aspherical. A pair of lenses, among the first lens to the seventh lens, allows paraxial areas opposing each other to be bonded to each other.

Abstract: The present disclosure discloses a camera optical lens. The camera optical lens including, in an order from an object side to an image side, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens. The first lens is made of plastic material, the second lens is made of plastic material, the third lens is made of glass material, the fourth lens is made of glass material, the fifth lens is made of plastic material, the sixth lens is made of plastic material, and the seventh lens is made of plastic material. The camera optical lens further satisfies specific conditions.

Abstract: A projection optical system (10) projects from a first image plane (5) on a reducing side to a second image plane (6) on an enlargement side. The projection optical system (10) includes a first optical system (11) that includes a plurality of lenses and forms a first intermediate image (51) formed inside the first optical system (11) by light incident from the reducing side into a second intermediate image (52) on the enlargement side of the first optical system; a second optical system (12) that includes a first reflective surface (M1) with positive refractive power which is positioned further to the enlargement side than the second intermediate image (52); and a glass block (30) that is disposed between the first optical system (11) and the first reflective surface (M1), the glass block (30) passing light rays from the first optical system to the second intermediate image.

Abstract: Embodiments include: a light emitting diode for emitting light; and a lens array including first to fourth lenses sequentially arranged in line in a first direction, wherein the first to fourth lenses are each convex lenses, the first lens and the fourth lens are the same in shape, the second lens and the third lens are the same in shape, the first and second lenses are each arranged in convex configurations in the first direction, the third and fourth lenses are each arranged in convex configurations in the direction opposite to the first direction, and the first direction is a direction oriented toward the first lens from the light emitting diode.

Abstract: An imaging lens according to the disclosure includes a negative front group, a stop, and a positive rear group. The front group includes a negative first lens having a meniscus shape with a convex surface facing the object side, a negative second lens having the meniscus shape with a convex surface facing the object side, and a positive third lens having a biconvex shape. The rear group includes a positive fourth lens, a negative fifth lens with a concave surface facing the image side, and a positive sixth lens.

Abstract: A disk scanning apparatus is used in combination with an imaging optical system and an imaging apparatus. The disk scanning apparatus includes a rotating disk and a relay optical system. In the rotating disk, a disk surface including a shielding part and a transmitting part is placed so as to be positioned on a focal plane of the imaging optical system. The relay optical system performs relaying of an optical image of a sample to the imaging apparatus. The relay optical system includes a front group having a positive power and a rear group having a positive power, in this order from the rotating disk side, and is configured so that a luminous flux between the front group and the rear group becomes an afocal luminous flux. The disk scanning apparatus further includes a structure configured to make the distance between the front group and the rear group variable.

Abstract: The color separation/light combining element included in an illuminator has at least one first region and at least one second region. The light ray flux contains a first light ray flux outputted from the first light emission unit and a second light ray flux outputted from the second light emission unit. a wavelength conversion element, a diffusive reflection element, and the color separation/light combining element are so disposed that part of the first light ray flux is incident on the diffusive reflection element via the first region, the other part of the first light ray flux is incident on the wavelength conversion element via the first region, a part of the second light ray flux is incident on the wavelength conversion element via the second region, and the second region combines the converted light with a part of light reflected off the diffusive reflection element to produce illumination light.

Abstract: A front projection display device is provided including an image-generating source configured to generate an image, a wide angle lens system adapted to receive the image, and a screen. The wide angle lens system may be configured to increase distortion of the image in a first stage and decrease distortion of the image in a second stage. The screen may be configured to receive the image from the wide angle lens system on a first side and reflect the image back to a viewer on the first side. In another embodiment, a screen is provided for a front projection system, the screen may be configured to receive light from a steep angle and may include any number of surface topographies configured to reflect light back to the viewer along a desired viewing plane.

Abstract: A projection lens includes a first lens group and a second lens group, all of which are arranged in sequence from a projection side to an image source side along an optical axis. The first lens group is with positive refractive power. The second lens group is with positive refractive power and includes a first lens, a second lens, a third lens and a fourth lens, wherein the first lens is with negative refractive power, the second lens is with positive refractive power, the third lens is with positive refractive power and the fourth lens is with positive refractive power. The first lens and the second lens are cemented together to form a cemented lens, the cemented lens is with negative refractive power. The first lens satisfies: ?0.579?f1/f??0.4 wherein f1 is an effective focal length of the first lens and f is an effective focal length of the projection lens.

Abstract: A projector includes: an optical element including first and second regions and which diffuses light that has entered the regions; an irradiation device for irradiating the first and second regions with light in a time-divisional manner; a polarization control unit disposed on a plane which is conjugate to a plane on which the optical element is disposed; and a spatial light modulator disposed in a light path from the optical element to the polarization control unit and which is illuminated with light that has been diffused by the first and second regions. The polarization control unit is configured to control the polarization state of light so that light that has been diffused by the first region becomes light of a first polarization component, and light that has been diffused by the second region becomes light of a second polarization component which differs from the first polarization component.

Abstract: An imaging lens consists of a front group and a rear group. The front group is composed of a lens having a negative meniscus shape with a convex surface on the object side, a negative lens, a negative lens, and a positive lens in order from the object side. The rear group is composed of a positive lens, a negative lens, a positive lens, and a positive lens in order from the object side. The imaging lens satisfies given conditional expressions.

Abstract: A front projection display device is provided including an image-generating source configured to generate an image, a wide angle lens system adapted to receive the image, and a screen. The wide angle lens system may be configured to increase distortion of the image in a first stage and decrease distortion of the image in a second stage. The screen may be configured to receive the image from the wide angle lens system on a first side and reflect the image back to a viewer on the first side. In another embodiment, a screen is provided for a front projection system, the screen may be configured to receive light from a steep angle and may include any number of surface topographies configured to reflect light back to the viewer along a desired viewing plane.

Abstract: The present invention discloses a near infrared lens, comprising four groups of lenses along the optical axis from the object space to the image space, wherein, the first lens is a meniscus-shaped lens with negative focal power, with the convex side facing the object space, and has aspherical surfaces; the second lens is a meniscus-shaped lens with positive or negative focal power, with the convex side facing the image space; the third lens is a convexo-convex, convexo-plane, or meniscus-shaped lens with positive focal power, and the convex side of the lens faces the object space if the lens is a convexo-plane or meniscus-shaped lens; the fourth lens is a lens with positive focal power, and has aspherical surfaces. With the above design, the near infrared lens can achieve high imaging quality and low distortion effects with large aperture and wide viewing angle.

Abstract: A projection zoom lens substantially consists of a negative first lens group and a positive second lens group, in this order from the magnification side. The first lens group substantially consists of a first lens which is a negative meniscus lens with a convex surface toward the magnification side. The second lens group substantially consists of a positive second lens, a third lens which is a positive meniscus lens with a convex surface toward the magnification side, a negative fourth lens, and a positive fifth lens, in this order from the magnification side. The first lens group and the second lens group move along the direction of the optical axis while changing magnification. At least one of the positive lenses within the entire system has an Abbe number and a refractive index within a predetermined range. The refractive indices of the first to third lenses satisfy a predetermined conditional expression.

Abstract: Disclosed is an optical system for a head-mounted display, in which image rays provided from a display device are diverged to form and provide an enlarged image. First, second, and third lenses or first, second, third, and fourth lenses are sequentially disposed from an object along an optical axis and provide the enlarged image on an image plane, and angles of principal rays are gradually increased from the optical axis toward an edge of the image plane. Thus, as the angles of principal rays increase, the angle of view is improved to provide a large image so that it is possible to appreciate a vivid image due to an increase in the sense of presence and the degree of involvement. The size of the entire optical system can be reduced, thus a head-mounted display can be made compact and lightweight.

Abstract: Projection lens having improved properties such as a high throughput are described. In one embodiment, a projection lens is described comprising in sequential order from a screen side a first lens group, a second lens group of positive refractive power, and a third lens group of positive refractive power. At least one lens group has an aspheric surface. The ratio of the focal length of the projection lens (F) to the focal length of each of the lens groups (F1, F2, and F3) is such that |F1/F|>5, 0.5<|F2/F|<0.9, and 1<F3/F<8. In another embodiment, a projection lens is described comprising in sequential order from a screen side a first lens group, a second lens group of positive refractive power, and a third lens group of positive refractive power. At least one lens group has an aspheric surface. The ratio of the focal length of the projection lens (F) to the focal length of each of the lens groups (F1, F2, and F3) is such that |F1/F|>5, 0.5<|F2/F|<2.0, and 1.4<F3/F<8.

Abstract: Techniques are described for designing and manufacturing a refractive surface that produces a desired image when placed over a target image. The refractive lens surface may include a set of lens patches, each of which indexes a region on the source image to refract light from the indexed region to recreate a patch of the target image. And together, the lenses reproduce the target image. In one embodiment, the refractive geometry of the lens surface (i.e., the shape of each lens) is determined by formulating and efficiently determining a solution to an inverse light transport problem. The solution may account for additional constraints imposed by the physical manufacturing procedure. Doing so results in a design for a refractive surface amenable to milling (or other manufacturing process).

Abstract: A unit magnification Wynn-Dyson lens for microlithography has an image field sized to accommodate between four and six die of dimensions 26 mm×36 mm. The lens has a positive lens group that consists of either three or four refractive lens elements, with one of the lens elements being most mirror-wise and having a prism-wise concave aspheric surface. Protective windows respectively reside between object and image planes and the corresponding prism faces. The lens is corrected for at least the i-line LED wavelength spectrum or similar LED-generated wavelengths.

Abstract: A projection optical system substantially consists of a first optical system composed of a plurality of lens groups and a second optical system composed of one reflection mirror having a convex aspherical surface arranged in this order from the reduction side, in which all optical surfaces constituting the first and second optical systems are formed so as to have rotationally symmetrical shapes around one common axis, the projection optical system is configured such that focus adjustment is performed by individually moving two lens groups in the first optical system along the common axis, and the lens disposed on the most magnification side in the reduction side lens group of the two lens groups is a lens having a convex surface on the magnification side, thereby magnifying and projecting an image formed on a conjugate plane on the reduction side to a conjugate plane on the magnification side.

Abstract: A projection lens of an imaging module and the imaging module are provided. The imaging module further has a light modulator to project a first image with a first aspect ratio. The projection lens comprises an anamorphic lens set and a projection lens set. The anamorphic lens set comprises a first cylinder lens, a second cylinder lens, a bi-convex cylinder lens and a bi-concave cylinder lens, which are set after the light modulator in sequence. The first cylinder lens has at least one flat surface, and the second cylinder lens has at least one convex surface. The anamorphic lens set projects the first image with the first aspect ratio into a second image with a second aspect ratio; the second aspect ratio is different from the first aspect ratio. The projection lens set receives and projects the second image with the second aspect ratio.

Abstract: There is provided a projection image display apparatus which is excellent in quality of a display screen image even if a projection lens using a plastic lens having an asymmetrical shape with respect to an optical axis is used. The apparatus includes a projection lens which obliquely projects video light on a screen, an integrator which aligns a polarization direction of light from a light source, and an image display element (P, PL) which modulates light having the aligned polarization direction by an image signal. The projection lens includes multiple plastic lenses, and each of the multiple plastic lenses is arrayed, respectively, by shifting a gate direction to each other by 180 degrees. When the projection lens includes n sheets (n is a natural number) of plastic lenses, each of the multiple plastic lenses may be arrayed, respectively, by shifting a gate direction to each other by (360/n) degrees.

Abstract: A projector lens system is provided. The projector lens system comprising, in order from a screen side thereof: a first negative lens that is made of resin and is convex on the screen side; a first positive lens that is made of glass and is biconvex; a stop; a cemented lens that has negative refractive power and is composed, in order from the screen side, of a second negative lens that is made of glass and a second positive lens that is made of glass; and a third positive lens that is made of resin, wherein a refractive index n1 of the first negative lens, a refractive index n2 of the first positive lens, a refractive index n32 of the second positive lens, and a refractive index n4 of the third positive lens satisfy the following conditions: 1.45?n1?1.60; 1.45?n4?1.60; 0.16?n2?n1?0.31; 0.16?n32?n4?0.31; 0.95?n1/n4?1.05; and 0.95?n2/n32?1.05.

Abstract: A projection lens for projecting an image beam is provided. The image beam is converted by a light valve from an illumination beam irradiating the light valve. The projection lens includes a first lens group, a second lens group, and a third lens group. The first lens group is disposed on a transmission path of the image beam, and has a first optical axis. The second lens group is disposed on both a transmission path of the illumination beam and the transmission path of the image beam, and between the light valve and the first lens group. The second lens group has a second optical axis. The second optical axis is inclined with respect to the first optical axis. The third lens group is disposed on the transmission path of the image beam, and between the first lens group and the second lens group. A projection apparatus is also provided.

Abstract: A projection type image display apparatus in which shortening of the projection distance (widening of the angle of view) and miniaturization of the projection optic system are realized is provided. It comprises, in a traveling direction of the light, an image display element, a lens group including a plurality of lenses, a first lens, a second lens, and a mirror to reflect light emitted from the second lens to be projected obliquely on a screen in this order. The refractive power of the first lens is positive and the refractive power of the second lens is negative. The first and the second lenses are moved in an interlocked relationship with each other along an optical axis of the lens group and a movement amount of the first lens is made larger than a movement amount of the second lens.

Abstract: A projection lens is composed of a positive first lens group, a negative second lens group, and a positive third lens group, which are sequentially arranged from the magnification side of the projection lens, and the reduction side of the projection lens is telecentric. Further, the following formulas (1) and (2) are satisfied: 0.30?d23/f3?0.65??(1); and 10?|D12/ff|??(2), where d23: space in air between the second lens group and the third lens group, f3: focal length of the third lens group, D12: total length of the first lens group and the second lens group in the direction of an optical axis, and ff: length from the most magnification-side surface in the entire system of the projection lens to a magnification-side focus position of the entire system.

Abstract: The present invention provides a micro-projection lens including first lens group, a second lens group, and a third lens group arranged in sequence along an optical axis from a screen side to a light modulator side. The first lens group has positive refractive power and includes at least an aspheric lens. The second lens group has negative refractive power and includes at least a glass tablet. The third lens group has positive refractive power and includes at least an aspheric lens. Therefore, the micro-projection lens of the present invention has a small size and high optical performance.

Abstract: In constructing a lens for projection substantially consisting of seven lenses, and the reduction side of which is telecentric, a first-lens-group is composed of two lenses including at least one negative lens. A second-lens-group is composed of a positive second-group first-lens having a convex surface facing the magnification side, a negative second-group second-lens having a concave surface facing the magnification side, a positive second-group third-lens having a convex surface facing the reduction side, a positive second-group fourth-lens, and a positive second-group fifth-lens in this order from the magnification side. The formulas (A) and (B) are satisfied: 1.2?Bf/f?2.5??(A); and f23/f?1.5??(B), where Bf is a back focus in air of an entire lens system, f is the focal length of the entire lens system, and f23 is the focal length of an air lens between a reduction-side surface of the second-group second-lens and a magnification-side surface of the second-group third-lens.

Abstract: A projector adapted to project an image includes: a detection section adapted to detect a motion of the projector; a determination section adapted to compare a detection result of the detection section with a predetermined criterion to perform determination on whether the projector is in a moving state or in a resting state; an adjustment section adapted to begin adjustment of at least one projection condition of the image in response to a transition of a determination result of the determination section from the moving state to the resting state; an auxiliary operation section adapted to auxiliary support the projection of the image by performing an operation with vibration; and a criterion determination section adapted to change the criterion based on a operation state of the auxiliary operation section.

Abstract: A projection lens includes a first lens group, a second lens group, and a third lens group. The first lens group is composed of a first lens. The first lens has a concave surface and a convex surface, and the concave surface of the first lens faces a reducing side of the projection lens. The second lens group has positive refractive power, and includes a second lens having positive refractive power and a third lens having negative refractive power. The second lens is a biconvex lens, and the third lens has a concave lens facing the reducing side. The third lens group is composed of a fourth lens, and the fourth lens has a convex surface facing a magnifying side of the projection lens. The first lens group, the second lens group, and the third lens group include at least two aspheric lenses.

Abstract: A projection lens PL comprises, in order from a projection side: a first lens component L1 which has positive refractive power and is biconvex; a second lens component L2 which has negative refractive power and is meniscus; and a third lens component L3 which has positive refractive power and has a convex lens surface facing the projection side, lens surfaces on the projection side and an object side of the first lens component L1 and lens surfaces on the projection side and the object side of the second lens component L2 being aspherical, and the following conditional expression being satisfied: 0.2<f/(?f2)<0.7 where f2 denotes a focal length of the second lens component, and f denotes a focal length of the projection lens.

Abstract: A method of forming thermoplastic polyurethane (TPU) into an optical lens. Suitable TPUs contain urethane (—NHCOO—) repeating units that are present in at least 23% by weight. This range of urethane weights is an indicator of a flexural modulus above 1,400 MPa. The TPUs have refractive indices above 1.54 and Abbe numbers above 27. They have glass transition temperatures above about 100 degrees C. The selected TPU can be injection molded to form ophthalmic lenses, that are well suited for use in rimless spectacles. The lenses are highly solvent resistant, while at the same time being readily tintable. The lenses made according the invention meet FDA 21 CFR 801.41 Impact Requirement, and ANSI Z87.1 high velocity impact (HVI) standard.

Abstract: A projection lens system includes, from the magnified side to the reduced side thereof, a first lens group having negative refractive power, a second lens group having positive refractive power, a third lens group having positive refractive power, and a field lens. The projection lens system satisfies the following conditions: 2.9<TT/f<3.7, and 1.85<f4/f<2.65, where TT is a total length of the projection lens system; f is an effective focal length of the projection lens system; f4 is an effective focal length of the field lens.

Abstract: This invention concerns an ergonomic optical see-through head mounted display device with an eyeglass appearance. The see-through head-mounted display device consists of a transparent, freeform waveguide prism for viewing a displayed virtual image, a see-through compensation lens for enabling proper viewing of a real-world scene when combined together with the prism, and a miniature image display unit for supplying display content. The freeform waveguide prism, containing multiple freeform refractive and reflective surfaces, guides light originated from the miniature display unit toward a user's pupil and enables a user to view a magnified image of the displayed content. A see-through compensation lens, containing multiple freeform refractive surfaces, enables proper viewing of the surrounding environment, through the combined waveguide and lens.

Abstract: In general, in a first aspect, the invention features a system that includes a microlithography projection optical system. The microlithography projection optical system includes a plurality of elements arranged so that during operation the plurality of elements image radiation at a wavelength ? from an object plane to an image plane. At least one of the elements is a reflective element that has a rotationally-asymmetric surface positioned in a path of the radiation. The rotationally-asymmetric surface deviates from a rotationally-symmetric reference surface by a distance of about ? or more at one or more locations of the rotationally-asymmetric surface.

Abstract: Disclosed is a projection optical system including a projection surface configured such that an image conjugate to an object is projected, plural optical elements having a refractive power, and a deflecting element having no refractive power configured to deflect an optical path of a light beam and to pass the light beam having a deflected optical path between the plural optical elements, wherein a normal line of the projection surface at a center of the projection surface does not pass through the plural optical elements or between the plural optical elements.

Abstract: The present invention provides a photographing optical lens assembly comprising, in order from an object side to an image side: a first lens element with positive refractive power having a convex object-side surface and a concave image-side surface; a second lens element with negative refractive power having a concave object-side surface and a convex image-side surface, the object-side and image-side surfaces thereof being aspheric; and a third lens element with negative refractive power having a convex object-side surface and a concave image-side surface, the object-side and image-side surfaces thereof being aspheric and at least one inflection point being formed on the image-side surface, wherein the lens assembly is further provided with a stop disposed between an object and the first lens element.