A device having a partially reflective cover, in particular for use as a decorative mirror element, is described. The device comprises a light source and a cover, which is arranged in front of the light source, the cover comprising a reflective polarizer and a circular polarizer, which is arranged behind the reflective polarizer.

A data center includes a wavelength source, a first optical component, a first communications device, and a second communications device. The wavelength source is configured to generate an N-wavelength laser beam. The first port of the first optical component is configured to receive an M-wavelength laser beam from the wavelength source. The second port of the first optical component is configured to send the M-wavelength laser beam to the first communications device. The M-wavelength laser beam includes at least a first-wavelength laser beam. The second port of the first optical component is further configured to receive a modulated first optical signal from the first communications device, the modulated first optical signal is obtained after the first communications device modulates a service signal onto the first-wavelength laser beam. The third port of the first optical component is configured to send the modulated first optical signal to the second communications device.

A three-dimensional light modulator, of which the pixels are combined to form modulation elements. Each modulation element can be coded with a preset discrete value such that three-dimensionally arranged object points can be holographically reconstructed. The light modulator is characterized in that assigned to the pixels of the modulator are beam splitters or beam combiners which, for each modulation element, combine the light wave parts modulated by the pixels by means of refraction or diffraction on the output side to form a common light beam which exits the modulation element in a set propagation direction.

A display apparatus includes: a display device configured to output a first image; an optical coupler configured to: combine the first image received through a first path from the display device with a second image received through a second path that is different from the first path, output, through an exit surface of the optical coupler, a first light corresponding to the first image in a first polarization and a second light corresponding to the second image in a second polarization; and a polarization selection optical system arranged on the exit surface of the optical coupler and configured to have different refractive power with respect to the first light of the first polarization and the second light of the second polarization.

An optical film, display module, and display screen, wherein the optical film comprises a main body, multiple microstructures, and an opaque layer. The microstructures are positioned on one side of the main body, and these microstructures are protruding arcuate structures. The opaque layer is affixed to the main body and is set opposite the microstructures on the other side of the main body, the opaque layer includes multiple apertures. Wherein, the center point of the apertures overlaps with the center point of the microstructures on a projection plane. Wherein, the equivalent diameter of the apertures divided by the equivalent diameter of the microstructures is less than or equal to 0.3, the equivalent diameter of the microstructures divided by the thickness of the main body is less than or equal to 1.3, and greater than or equal to 0.7. Wherein, the opaque layer is oriented towards the light source. The beneficial effect is that it can produce better collimated light, further improving the performance of the display module.

Provide are an optical element that can improve a utilization efficiency of light while increasing an optical path length, an image display unit, and a head-mounted display. The optical element includes, in the following order: a first absorptive linearly polarizing plate; a first reflective linearly polarizing plate; a first retardation plate; a partially reflecting mirror; a second retardation plate; and a second reflective linearly polarizing plate, in which a turning direction of circularly polarized light that is reflected from the first reflective linearly polarizing plate in a case where light transmits through the first retardation plate and is incident into the first reflective linearly polarizing plate is opposite to a turning direction of circularly polarized light that is reflected from the second reflective linearly polarizing plate in a case where light transmits through the second retardation plate and is incident into the second reflective linearly polarizing plate.

The invention relates to a surveying apparatus, in particular tachymeter, laser scanner, profiler or laser tracker, comprising an electronic laser distance measuring module, which comprises an optical transmission channel and an optical reception channel for laser measurement radiation, wherein a variable optical attenuation unit for the laser measurement radiation is provided in the optical transmission channel and/or optical reception channel. According to the invention, light impinging on the attenuation unit is attenuated by means of liquid crystals. The attenuation unit comprises at least one polarizer, in particular comprising a polarization sheet, a liquid crystal shutter, in particular comprising nematic liquid crystals, having a variable transmission, a first analyzer, in particular comprising a polarization sheet.

An optical device includes a first substrate which is light-transmissive, a second substrate which is light-transmissive and opposes the first substrate, a light distribution layer which is interposed between the first substrate and the second substrate and distributes incident light, and an optical element which is disposed on one of a surface of the second substrate on a side opposite to a side facing the first substrate and a surface of the first substrate on a side opposite to a side facing the second substrate. The light distribution layer includes an optical medium containing a birefringent material and an uneven structure. The optical element has an optical property of reducing an amount of at least one of first polarized light and second polarized light that differ in a polarization direction.

The liquid crystal drive apparatus drives a liquid crystal element. The apparatus includes an image data producer producing, using each of multiple input frame image data continuously input thereto, first frame image data and second frame image data, and a driver sequentially controlling, depending on the first frame image data and the second frame image data, application of a first voltage or a second voltage lower than the first voltage to each of multiple pixels of the liquid crystal element in respective multiple sub-frame periods included in one frame period to cause that pixel to form a tone. Pixel data at pixel positions corresponding to each other in the first and second frame image data have mutually different tones. A tone difference between the mutually different tones is 20% or less of a higher one of the mutually different tones.

To provide an image display device capable of remediation of color breakup, and an electronic device including the image display device. An image display device includes: a first display panel whose transmittance or reflectance of light is controlled on the basis of a first video signal; a second display panel whose transmittance or reflectance of light is controlled on the basis of a second video signal; a light irradiation unit configured to irradiate the first display panel with color light according to the first video signal for driving the first display panel, and to irradiate the second display panel with color light according to the second video signal for driving the second display panel; and a control unit configured to generate the first video signal corresponding to first color light that is one among red color light, green color light, and blue color light, and generate the second video signal that causes emission of second color light that brings the first color light close to white light.