The current generation of Microsoft HoloLens uses a combination of waveguides and light projectors for its display system. HoloLens 2 uses laser light to illuminate the display. Even though the display system in HoloLens 2 is improved when compared to the original HoloLens, it is far from perfect. Recently, we came across a new patent from Microsoft in the US. According to this patent, Microsoft is exploring ways to use the MicroLED display system in HoloLens to reduce the form factor without compromising the display quality or user experience.
MicroLED displays do not need separate illumination optics. In the proposed system, Microsoft will use three monochrome projectors to generate three monochrome images (e.g., red, blue, and green images) that are separately inputted into a single waveguide of the HoloLens and combined to form an image that is displayed to the user.
By utilizing a single waveguide that includes a plurality of spatially separated input regions (e.g., a region for inputting blue light, a region for inputting red light, a region for inputting green light), the MicroLED display system of the present disclosure may reduce the form factor of the HMD device because of the reduced number of plates that may be required to combine the three monochrome images.
You can read more about this MicroLED display system from the source link below.