A display device and a head-mounted display apparatus are provided. The display device comprises a display unit and a first optical module. The display unit further comprises a plurality of display areas, and each display area includes a plurality of pixel units. Display colors of pixel units in each display area are the same, and the display colors of pixel units in different display areas are different. The first optical module is configured to converge and overlap image light of the plurality of display areas to form a display image.

A color separation device changes a light path according to the wavelengths of incident light and an image sensor has improved light utilization efficiency by using the color separation device. The color separation device may include a first element having a first refractive index that varies according to wavelengths of light along a first refractive index distribution curve, and a second element having a second refractive index that varies according to wavelengths of light along a second refractive index distribution curve, the second refractive index distribution curve being different from the first refractive index distribution curve. The color separation device may be manufactured by simply joining two elements, namely, the first and second elements, together and thus may be more easily manufactured and perform more effective color separation.

A projection system arranged to receive an image for projection. The image is a colour image comprising a first colour component and a second colour component. The system is arranged to calculate a first hologram of the first colour component and a second hologram of the second colour component. The system is further arranged to add content of the second colour component to the first colour component before calculating the first hologram. The first hologram contains information of the first colour component and information of at least a portion of the second colour component. The system is further arranged to form a first holographic reconstruction by illuminating the first hologram with first colour light and to form a second holographic reconstruction by illuminating the second hologram with second colour light. The first holographic reconstruction changes the chromaticity of the at least a portion of the second colour component.

Systems and methods for filtering an optical beam are described. In one implementation, a system for filtering an input optical beam includes a first beamsplitter, a first spectral slicing module, a second spectral slicing module, and a second beamsplitter. The first beamsplitter is configured to split the input optical beam into a first optical beam and a second optical beam. The first spectral slicing module has a first passband and is configured to filter the first optical beam. The second spectral slicing module has a second passband and is configured to filter the second optical beam. The second beamsplitter is configured to combine the first optical beam and the second optical beam into an output optical beam. The first and second spectral slicing modules may each comprise a longpass filter and a shortpass filter aligned along its optical axis, and the longpass filter and/or the shortpass filter are rotatable relative to the optical axis. Advantageously, the optical system allows for tunable spectral filtering of the input optical beam suitable for 2-D imaging systems.

The disclosed projector device may include (1) a first monochromatic emitter array having a plurality of emitters of a first color disposed in a two-dimensional configuration and (2) a second monochromatic emitter array having a plurality of emitters of a second color disposed in a two-dimensional configuration. The first and second monochromatic emitter arrays may be configured to emit images of the first and second colors into a waveguide configuration, and the first color may be different than the second color. Associated display systems and methods are also provided.

Provided is an illumination system for providing an illumination beam. The illumination system includes at least one light source, a movable reflective element, a lens element, and a light uniformizing element. The light source is configured to emit at least one beam. The beam is reflected by the movable reflective element, and then passes through the lens element and the light uniformizing element to form an illumination beam. An optical effective area of the beam on the lens element is configured to be larger than that of the beam on the movable reflective element by motion of the movable reflective element. The optical effective area is an area of a union of each beam that irradiates the lens element or the movable reflective element at different times. A projection device is also provided. The illumination system and projection device provide a uniformized illumination beam and improve the projection effect.

An illumination system, including an excitation light source, a beam splitting filter device, and a wavelength conversion element, is provided. The excitation light source is configured to emit an excitation beam. The beam splitting filter device includes a light penetration region and a beam splitting filter region. The excitation beam penetrates the light penetration region to form a first beam. The excitation beam is reflected by the beam splitting filter region. The wavelength conversion element is disposed on a transmission path of the excitation beam coming from the beam splitting filter region. The wavelength conversion element is configured to convert the excitation beam coming from the beam splitting filter region to a conversion beam and transmit the conversion beam back to the beam splitting filter region, and the conversion beam at least partially penetrates the beam splitting filter region to form a second beam. A projection device is also provided.

The disclosed projector device may include (1) a first monochromatic emitter array having a plurality of emitters of a first color disposed in a two-dimensional configuration and (2) a second monochromatic emitter array having a plurality of emitters of a second color disposed in a two-dimensional configuration. The first and second monochromatic emitter arrays may be configured to emit images of the first and second colors into a waveguide configuration, and the first color may be different than the second color. Associated display systems and methods are also provided.

An illumination system and a projection device are disclosed. The illumination system includes laser light sources, a color wheel element and light combiners. The laser light sources provide laser lights of different colors. One of the laser light sources is disposed on an optical axis. The color wheel element is disposed on the optical axis and on a transmission path of the laser lights, and adjusts wavelengths of the laser lights. The light combiners are disposed on the optical axis and between the laser light source and the color wheel element. The light combiners are pervious to the laser lights or reflect the laser lights to combine the laser lights on the optical axis. The illumination system uses the laser light sources to provide lights of different colors, and in collaboration with a configuration structure of the optical elements thereof, the laser lights with a wider color gamut are provided.

An illumination optical system including one or more light sources each including a solid-state light-emitting device and an optical member. The optical member includes an integrator including a first fly-eye lens on which light from the solid-state light-emitting device is incident and a second fly-eye lens on which light from the first fly-eye lens is incident, and uniformizing a luminance distribution of light in a predetermined illumination region illuminated with light incident from the solid-state light-emitting device. A major-axis direction of a luminance distribution shape of light incident on an incident plane of the first fly-eye lens is different from arrangement directions of the cells in the first fly-eye lens.