Raster scan produces a much brighter and higher quality image. The max duty cycles of the lasers are about 90% for the raster scan. The max laser duty cycles for a Lissajous scan are less than 50% due to issues with brightness uniformity. Therefore a raster scan display produces a much brighter screen compared to the Lissajous scan that some competitors have adopted.
Biaxial Single Mirror Design
This greatly simplifies the optical module assembly alignment work and greatly improves the production yield. Some competitors utilize two mirrors for the biaxial scan. The laser first aims at a smaller fast scanning uniaxial mirror. This mirror produces a scanned line that is scanned by a second larger and slower scanning mirror to produce a complete two dimensional scan. It is exponentially more difficult to align two mirrors with lasers than to align a single mirror.
Ultimems MEMS biaxial single mirror design
Pure Electrostatic Actuation Method
The benefits of the pure electrostatic design are high assembly yield and small module size. Some of our competitors utilize electromagnetic force for the slow scan and fast scan. Our pure electrostatic biaxial mirror is made completely inside the foundry. Most of our competitors use either a moving coil or moving magnet design for the scan. This creates many alignment issues outside of the foundry. First, the assembly house needs to align the coil and magnet. Secondly, for the moving magnet design, the magnet and mirror need to be aligned and combined at the assembly house before magnet and coil alignment. For the moving coil design, the magnet must first be attached to an iron yoke to complete the magnetic field loop.