Techniques and mechanisms for fabricating an eyepiece from a lens blank including blank bodies that are bonded to each other. In an embodiment, the blank bodies are formed by injection molding and adhered to one another. Fabrication of the eyepiece includes variously machining the blank bodies to shape respective lens bodies of the eyepiece. One or more blocking structures are coupled to reinforce the lens blank during at least part of such machining. In another embodiment, any blocking structures that are to resist forces of a particular machining process are coupled only indirectly to one of the blank bodies.

An observation optical system includes a display element and an eyepiece lens disposed on an eyepoint side of the display element. The eyepiece lens includes a first lens having positive optical power, a second lens having negative optical power, and a third lens consecutively in order from closest to a display element side to the eyepoint side. In a case where a half value of a longest diameter of a display region in the display element is denoted by H, and a focal length of the eyepiece lens in a state where diopter is −1 diopter is denoted by f, the observation optical system satisfies a conditional expression represented by 0.35<H/f<0.6.

An observation optical system includes a display element and an eyepiece lens disposed on an eyepoint side of the display element. The eyepiece lens includes a first lens having positive optical power, a second lens having negative optical power, and a third lens consecutively in order from closest to a display element side to the eyepoint side. In a case where a half value of a longest diameter of a display region in the display element is denoted by H, and a focal length of the eyepiece lens in a state where diopter is −1 diopter is denoted by f, the observation optical system satisfies a conditional expression represented by 0.35<H/f<0.6.

Implementations are described of an eyepiece for a head wearable display. The eyepiece includes a curved lightguide for guiding display light via total internal reflection between a peripherally-located input surface and a viewing region and an output coupler disposed across the viewing region to redirect the display light towards an eyeward direction for output from the curved light guide. The output coupler has an optical axis and has a set of reflective surfaces that includes at least two individual reflective surfaces to reflect incident display light toward the eyeward direction in at least two different directions relative to the optical axis of the output coupler. Other embodiments are disclosed and claimed.

An augmented reality display device is used to provide an augmented reality image to one eye of a user. The augmented reality display device includes a curved eyepiece, multiple first micromirrors and two first displays. These first micromirrors are disposed on the curved eyepiece. The two first displays are respectively disposed on two opposite sides of the curved eyepiece. Each first display is for emitting a first image beam. These first micromirrors are for imaging two first image beams emitted by the two first displays onto a retina of the eye to form the augmented reality image. Among them, the horizontal field of view formed by these first micromirrors to the eyes falls within the range of 80 degrees to 110 degrees.

An observation optical system of a real-image type includes, in order from the object side, an objective system, a reverse-erecting system that s erects an inverted image formed by the objective system, and an eyepiece system that allows a pupil to observe an erect image formed by the reverse-erecting system. The objective system includes, in order from the object side, a first lens having a negative power and a second lens having a positive power. The eyepiece system includes, in the order from the object side, a third lens having a positive power, a fourth lens having a negative power, a fifth lens having a positive power, and a sixth lens having a positive power.

The multifunctional pocket knife (1) is composed of a handle (2) formed by two joined-together flanks (3, 3′) that provide at least one stowage space (4) for tools that each pivot about link pins (5, 5′) arranged at each end of the handle (2). It is characterized in that it comprises a planar tick-removal instrument (6) that pivots about one of said link pins (5, 5′) and that extends along the longitudinal axis of the pocket knife. Tick-removal instrument (6) designed to be incorporated into a multifunctional pocket knife (1).

An enhanced vision system includes a first optic subsystem and a transparent photodetector subsystem disposed within a common housing. The first optic subsystem may include passive devices such as simple or compound lenses, active devices such as low-light enhancing image intensifiers, or a combination of passive and active devices. The transparent photodetector subsystem receives the visible image exiting the first optic subsystem and converts a portion of the electromagnetic energy in the visible image to a signal communicated to image analysis circuitry. On a real-time or near real-time basis, the image analysis circuitry detects and identifies structures, objects, and/or individuals in the visible image. The image analysis circuitry provides an output that includes information regarding the structure, objects, and individuals to the system user contemporaneous with the system user viewing the visible image.

A head mounted display includes first and second light source modules, a light reversely turning module, an image output module, first and second eyepiece modules, and a beam splitting mirror. The first and second light source modules are respectively configured to emit first and second lights. The image output module is configured to receive the first and second lights, generating first and second image lights with corresponding image information respectively. The light reversely turning module is optically coupled between the first light source module (or the second light source module) and the image output module, making a propagating direction of the first light (or the second light) in reverse to that of the first image light (or the second light). The beam splitting mirror is optically coupled between the image output module and the first/second eyepiece module, guiding the first/second image light into the first/second eyepiece module.

Disclosed are transparent energy relay waveguide systems for the superimposition of holographic opacity modulation states for holographic, light field, virtual, augmented and mixed reality applications. The light field system may comprise one or more energy waveguide relay systems with one or more energy modulation elements, each energy modulation element configured to modulate energy passing therethrough, whereby the energy passing therethrough may be directed according to 4D plenoptic functions or inverses thereof.