Circuit for detecting a clock error in a scanned-image system and related circuits, systems, and methods

An image system, comprising:

• a beam sweeper;
• a first driver operable to drive the beam sweeper in a first dimension such that the beam sweeper has a sweep phase;
• a clock generator operable to generate a pixel clock having a clock phase;
• a beam generator coupled to the clock generator and operable to direct a beam toward the beam sweeper in response to the pixel clock;
• a sensor operable to detect the beam redirected by the beam sweeper;
• and
• a phase detector coupled to the sensor and operable to detect an error in the clock phase from the detected beam.

A method, comprising:

• activating a beam in response to a clock as the beam moves in a direction, the clock having a phase;
• determining a first position of the activated beam as the beam moves in the direction;
• activating the beam in response to the clock as the beam moves in an opposite direction;
• determining a second position of the activated beam as the beam moves in the opposite direction;
• and
• detecting an error in the phase of the clock from the first and second positions.

A method, comprising:

• activating a beam in response to a clock as the beam moves in a direction;
• determining a position of the activated beam as the beam moves in the direction;
• and
• detecting from the position of the beam an error in a distance that the beam sweeps in a dimension perpendicular to the direction.