MEMS Micromirror Limit Structure for Beam Breakage Prevention

The patent introduces a position limiting structure (limit groove and limit block) that preemptively prevents excessive displacement and rotation of the movable layer before it can cause support beam breakage. The limit groove is formed on the substrate and the limit block is disposed on the movable layer, creating a mechanical constraint that stops the movable layer at a safe position before excessive stress accumulates in the support beam.

The position limiting structure is designed and integrated into the device before operation. The limit groove and limit block are formed during manufacturing, establishing predetermined mechanical constraints that guide and restrict the movement of the movable layer within safe boundaries, preventing catastrophic failure before it can occur.

The position limiting structure (limit groove and limit block) provides preliminary protection by mechanically preventing the movable layer from rotating beyond a safe angle. This constraint ensures that the support beam never experiences stress beyond its structural limits, allowing the beam to be designed with optimal flexibility for optical modulation without compromising strength.

The limit groove is designed with a curved profile that guides the movable layer through a controlled arc of rotation. This curved constraint allows the support beam to flex within a predetermined safe range while preventing excessive rotation that would cause breakage, effectively decoupling the rotation angle range from the beam strength requirement.