An imaging optical system includes six lens elements which are, in order from an object side to an image side: a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element. Each of the six lens elements has an object-side surface facing toward the object side and an image-side surface facing toward the image side. At least one of the six lens elements is a freeform lens element, and at least one of the object-side surface and the image-side surface of the at least one freeform lens element is a freeform surface.

A test fixture (10) for HUD windshields (12) wherein aspherical devices (26) compensate for complex curvatures and optical aberrations in a heads-up display surface (16) of the windshield. Tunable lenses cooperate with a movable test matrix to improve image resolution and enhance ghost image reduction.

An eyepiece for projecting an image to an eye of a viewer includes a waveguide configured to propagate light in a first wavelength range, and a grating coupled to a back surface of the waveguide. The grating is configured to diffract a first portion of the light propagating in the waveguide out of a plane of the waveguide toward a first direction, and to diffract a second portion of the light propagating in the waveguide out of the plane of the waveguide toward a second direction opposite to the first direction. The eyepiece furthers include a wavelength-selective reflector coupled to a front surface of the waveguide. The wavelength selective reflector is configured to reflect light in the first wavelength range and transmit light outside the first wavelength range, such that the wavelength-selective reflector reflects at least part of the second portion of the light back toward the first direction.

The present disclosure relates to an imaging device capable of achieving miniaturization and height reduction of a device configuration, reducing generation of a flare or a ghost, preventing separation of a lens. A size relation of “solid-state imaging element>lens non-effective region>lens effective region” is established in a vertical direction with respect to an incident direction of incident light. The present disclosure is applicable to an imaging device.

An optical element driving mechanism is provided, including a fixed part, a movable part and a driving assembly. The fixed part has a main axis, includes an outer frame and a base. The outer frame has a top surface and a sidewall. The top surface intersects the main axis. The sidewall extends from the edge of the top surface along the main axis. The base includes a base plate intersecting the main axis and securely connected to the outer frame. The movable part moves relative to the fixed part, and connects to an optical element having an optical axis. The driving assembly drives the movable part to move relative to the fixed part. The main axis is not parallel to the optical axis.

An eyepiece includes a planar waveguide having a front surface and a back surface. The eyepiece also includes a grating coupled to the back surface of the planar waveguide and configured to diffract a first portion of the light propagating in the planar waveguide out of a plane of the planar waveguide toward a first direction and to diffract a second portion of the light propagating in the planar waveguide out of the plane of the planar waveguide toward a second direction opposite to the first direction and a wavelength-selective reflector coupled to the front surface of the planar waveguide. The wavelength-selective reflector comprises a multilevel metasurface comprising a plurality of spaced apart protrusions having a pitch and formed of a first optically transmissive material and a second optically transmissive material disposed between the spaced apart protrusions.

A diffractive beam expander device (EPE1) includes a first spectral filter region (C2a) and a second spectral filter region (C2b) to provide a first optical route for blue and green light (B, G), and to provide a second optical router for red light (R). The expander device (EPE1) includes a first Bragg grating region (BRGa) to enhance optical absorption of red light (R) in the first spectral filter region (C2a). The expander device (EPE1) includes a second Bragg grating region (BRGa) to enhance optical absorption of blue light (B) in the second spectral filter region (C2b).

Provided is a glass sheet capable of suppressing the generation of stray light when used as a light-guiding plate of an eyeglass-type device such as a head-mounted display. The glass sheet is a glass sheet (1) including a first principal surface (1a) and a second principal surface (1b) opposed to each other and an end surface (1c) connecting the first principal surface (1a) and the second principal surface (1b) to each other, wherein the glass sheet (1) has a refractive index (nd) of from 1.6 to 2.2 and has an R shape in at least part of the end surface (1c), and the end surface (1c) has a surface roughness Ra of 100 nm or less.

A floating-information display includes a first quarter-wave retarder disposed on a side of an optical plate. A reflective polarizer is disposed between the first quarter-wave retarder and the optical plate. A first display is configured to transmit a first image along a first axis through the first quarter-wave retarder to the reflective polarizer. The reflective polarizer redirects the first image along a second axis through the first quarter-wave retarder toward a viewer. The first image appears to the viewer to be oriented normal to the second axis and at a first location. A second display is configured to transmit a second image to the optical plate. The second image is transferred through the first quarter-wave retarder along the second axis toward the viewer. The second image appears to the viewer to be oriented normal to the second axis and at a second location.

An optical filter comprises at least one optical member that transmits light, wherein a first optical film that reflects at least one of light in a longer wavelength band than a first wavelength and light in a shorter wavelength band than a second wavelength is formed on a first surface, and a second optical film that reflects at least one of light in a longer wavelength band than a third wavelength and light in a shorter wavelength band than a fourth wavelength is formed on a second surface, the second surface being different from the first surface, and the first wavelength and the third wavelength are different from each other by a first predetermined amount, and the second wavelength and the fourth wavelength are different from each other by a second predetermined amount.