A projection image display device of the present disclosure includes a light source, an image forming element that forms an image, a color separating and combining unit that separates first illumination light and second illumination light, and combines first projection light and second projection light reflected by the image forming element, and a notch filter that is disposed between the light source and the color separating and combining unit. A first dichroic filter reflects the first illumination light and the first projection light. A first incident angle of the first illumination light with respect to the first dichroic filter is different from a second incident angle of the first projection light with respect to the first dichroic filter. The notch filter attenuates light in a first wavelength band including a boundary between a wavelength band of the first illumination light and a wavelength band of the second illumination light.

A display device includes a laser irradiation device and a control device. The laser irradiation device is configured to irradiate an irradiation point located at a display position in air, with a laser beam having a wavelength equal to or larger than 380 nm and equal to or smaller than 780 nm and produce plasma at the display position. The control device is configured to control intensity of the laser beam emitted from the at least one laser irradiation device so that a relationship between intensity of plasma light emitted from the plasma at the display position and intensity of scattered light produced from the laser beam and scattered by the plasma becomes a predetermined relationship to display a color pixel.

A light engine includes an image surface, a projected light surface, a projection lens assembly, and a plurality of folding elements. The image surface has three image areas. The projected light surface has three light sources that provide light with different wavelengths. The plurality of folding elements are arranged along a light emitting axis. The image surface and the projected light surface are substantially in parallel with the light emitting axis, and there is an air gap located between the image surface and the projected light surface. The three light sources respectively correspond to the plurality of folding elements and respectively correspond to the three image areas, and the light emitting axis and the projection lens assembly are disposed on the same optical path.

A phase difference compensation element, including: a transparent substrate; a first optical anisotropic layer that includes an inorganic material, and has a C-plate retardance; and a second optical anisotropic layer that includes an inorganic material, and includes an oblique angle vapor deposition film that does not have an O-plate retardance, wherein the phase difference compensation element including the first optical anisotropic layer and the second optical anisotropic layer in combination has a quasi-O-plate retardance.

A light emitting apparatus includes an electrode and a laminated structure. The laminated structure includes an n-type first semiconductor layer, a light emitting layer, a p-type second semiconductor layer, a tunnel junction layer, and an n-type third semiconductor layer. The electrode is electrically connected to the first semiconductor layer. The first semiconductor layer, the light emitting layer, the second semiconductor layer, the tunnel junction layer, and the third semiconductor layer are arranged in a presented order. The light emitting layer and the first semiconductor layer form a columnar section.

An illumination system, including a light source module, a phosphor wheel, a light recycling element, and a light uniformizing element, is provided. The light source module emits an excitation light beam. The phosphor wheel includes a phosphor region. At a second timing, the other part of the excitation light beam transmitted to the phosphor region forms an unconverted light beam and is transmitted to the light recycling element, and is reflected by the light recycling element to form a recycled light beam. A part of the recycled light beam is converted into a second converted light beam. A first converted light beam and the second converted light beam are transmitted to the light uniformizing element through a same path, so that the illumination system outputs second light in the illumination light beam. A projection apparatus is also provided.

A structured light projection module and a depth camera are provided. The structured light projection module includes: a light source array including a plurality of sub-light sources arranged in a two-dimensional pattern and configured to transmit array beams corresponding to the two-dimensional pattern; a lens configured to receive and converge the array beams; and a diffractive optical element configured to receive the array beams that are emitted after being converged by the lens and project beams in a structured light speckle pattern. The structured light speckle pattern is formed through staggered superposition of at least two secondary structured light speckle patterns. Each secondary structured light speckle pattern is formed through a tiling arrangement of multiple sub-speckle patterns generated by a portion of the sub-light sources, and comprises speckles formed by diffracting an individual sub-light source via the diffractive optical element.

A projection module and a terminal are provided. The projection module includes a base, a housing, a first light source, a second light source and an optical element. The housing is disposed on the base, and defines an accommodating cavity together with the base. The first light source is disposed on the base and arranged in the accommodating cavity. The second light source is disposed on the base and arranged in the accommodating cavity. The optical element is disposed on the housing and includes a diffraction area and a diffusion area. The first light source aligns with the diffraction area, the second light source aligns with the diffusion area, the diffraction area is configured to diffract light passing through the diffraction area, and the diffusion area is configured to diffuse light passing through the diffusion area.

A structured light projector includes a light source configured to emit light, a structured light pattern mask configured to receive the light emitted by the light source and including a first region configured to generate a first structured light having a first polarization and a second region configured to generate a second structured light having a second polarization that is different from the first polarization, and a polarization multiplexing deflector configured to deflect the first structured light and the second structured light generated by the structured light pattern mask, to different directions, respectively.

A method of manufacturing a light emitting module comprising at least one light emitting device in which a plurality of light emitting elements are mounted, includes: providing a plurality of light emitting devices including one or more first light emitting devices and one or more second light emitting devices, wherein a number of the light emitting elements mounted in the first light emitting device is different from a number of the light emitting elements mounted in the second light emitting device; providing a first mounting substrate having a mounting surface provided with a plurality of connection patterns having the same pattern, each of the connection patterns corresponding to a respective one of the light emitting devices; and mounting at least some of the plurality of light emitting devices, selected from the one or more first light emitting devices and one or more second light emitting devices, on the connection patterns.