Scanning projector with non-rectangular display

摘要

A scanning beam projection system includes a scanning mirror having a fast-scan axis and a slow-scan axis. Movement on the fast-scan axis is controlled by a fast-scan scanning mirror control system. The control system receives position information describing angular displacement of the mirror. A fast-scan drive signal is generated that causes the scanning mirror to oscillate at a resonant frequency with a varying amplitude.

主权项

1. An apparatus comprising:
a scanning mirror having a fast-scan axis and a slow-scan axis, the fast-scan axis having a position detector to provide an analog fast-scan position signal that corresponds to an angular displacement of the scanning mirror on the fast-scan axis; and a control loop coupled to be responsive to the analog fast-scan position signal, the control loop configured to modify a scanning mirror drive signal to produce a non-uniform fast-scan amplitude across each sweep on the slow-scan axis; wherein the control loop includes:
an amplitude detector that includes a peak detector to detect an amplitude of the analog fast-scan position signal and produce a digital amplitude signal; anda plurality of least mean square (LMS) tone adders to determine harmonically related components of a fast-scan amplitude drive signal in response to the digital amplitude signal.