The present invention is an optical assembly featuring an architecture which allows adjustment of both objective lenses and the electronic sensing assemblies in the optical assembly. Electrical connections in the housings of the various subassemblies allow focusing adjustment by rotational and/or translational movement for increased adjustability.

An electronic view finder includes a display element that displays an image, and an eyepiece lens that is disposed on an eyepoint side of the display element and that is used for observing the image. The eyepiece lens consists of a first lens, a second lens having refractive power of a different sign from the first lens, and a third lens having positive refractive power in order from a display element side. Diopter is adjustable by moving at least one lens of the eyepiece lens. A television distortion of the image displayed by the display element varies depending on the diopter.

An electronic view finder includes a display element that displays an image, and an eyepiece lens that is disposed on an eyepoint side of the display element and that is used for observing the image. The eyepiece lens consists of a first lens, a second lens having refractive power of a different sign from the first lens, and a third lens having positive refractive power in order from a display element side. Diopter is adjustable by moving at least one lens of the eyepiece lens. A television distortion of the image displayed by the display element varies depending on the diopter.

A night sky viewing tent structure having specific features for enhanced night sky viewing is disclosed. In one embodiment, the night sky viewing tent structure comprises roof cut-outs to allow telescope lenses to extend through the roof for star viewing while still protecting users. In other embodiments, the tent structure roof cover is at least partially transparent with one or more sections providing magnification for improved night sky viewing. In another embodiment, the tent structure covering is at least partially photochromic, such that it is clear in low light conditions, and substantially tinted in full light or day light conditions. In other embodiments, the tent structure cover is manufactured with one or more coatings to absorb ultraviolet rays of less than 400 nanometers. In various embodiments, the night sky viewing tent structure is formed using at least one flexible rib element and a cover element.

A user-wearable fluorescence based visualization system comprising a multi-light lamp assembly that provides for the selected output of light using multiple light emitting sources, wherein the outputted light may be tailored to generate response wavelength by the interaction of the emitted light and a tissue illuminated by the emitted light, through the process of fluorescence, and a viewing system that allows a practitioner view the fluorescent light generated by the tissue, and distinguish between healthy and diseased tissues.

An optical lens arrangement comprises a first Fresnel lens element and a second lens element. The first Fresnel lens element defines a flat surface side and an opposite faceted surface side defining wedge and draft faces. The flat surface side faces towards the eye of a user and the opposite faceted surface side faces away from the eye of the user. The second lens element interfaces with the faceted surface side of first Fresnel lens. The second lens element is selected from the group consisting of: a second Fresnel lens element, a singlet lens element, a doublet lens element and any combination thereof. The first Fresnel lens is proximal relative to the eye of the user and the second lens element is distal relative to the eye of the user. Head mounted devices (HMD) including these optical lens arrangements are provided. Methods of making such optical lens arrangements and HMDs are also provided.

A fixture used in the manufacture of an eyepiece, to cut the eyepiece to a particular shape, and a method of using the fixture to cut the eyepiece to have a desired shape. Embodiments are directed to a configurable fixture to align, hold, and protect a plastic sheet (e.g., a wafer) while a laser cutting apparatus is cutting one or more eyepieces out of the wafer. During the cutting, the fixture protects the eyepieces from reflected laser light by providing voids around the laser cutting lines, and by supporting each eyepiece near its perimeter. The fixture can be quickly rearranged for different eyepieces, different eyepiece shapes, and/or different plastic sheet sizes.

An optical system with adjustable eye relief includes a relay lens assembly. The relay lens assembly is defined by a collimating lens and a focusing lens. The optical system includes an aperture stop. The aperture stop is configured to shift axially along an optical axis between the collimating lens and the focusing lens. The optical system also includes an afocal lens assembly. The afocal lens assembly is defined by the focusing lens and an eyepiece. Additionally, an axial shift of the aperture stop along the optical axis between the collimating lens and the focusing lens changes an eye relief of the eyepiece based on a transverse magnification of the afocal lens assembly.

A screen magnifier includes a magnifier body and a mounting seat. The magnifier body includes a magnifying glass. A rotating shaft is disposed on the magnifier body. The rotating shaft is disposed perpendicular to a glass surface of the magnifying glass. Mounting holes are on the mounting seat. The rotating shaft is movably connected with the mounting holes. The mounting holes extend along a horizontal direction. The rotating shaft is disposed in the mounting holes. The magnifier body rotated around an axis of the rotating shaft, and the magnifier body is switched between a horizontal position and a vertical position by rotating.

There is provided a highly efficient virtual image projection device in a small size that displays images of high luminance in which an illumination system is reduced in size with no degradation in an effective luminous light beam. A virtual image projection device that shows video to a human eye includes a virtual light source surface (116) that emits a light beam in a predetermined angular distribution, an image forming lens (117) that condenses the light beam from the virtual light source surface (116), and a display (120) that creates video. When the virtual light source surface (116) is disposed at a nearly focal position on the front side of the image forming lens (117), the display (120) is disposed at a nearly focal position on the rear side of the image forming lens.