Abstract: A circuit for detecting a phase error between a clock signal and a beam position includes a beam generator, sensor, and phase detector. The beam generator directs a beam toward a beam sweeper in response to a clock signal. The sensor, which is disposed at a mid line of a region that the beam sweeper scans, detects the beam from the beam sweeper, and the phase detector detects an error in the clock phase from the detected beam. Such a circuit can automatically detect the phase error in the pixel clock and correct this error, thus eliminating the need for a manual phase-error corrector.

Abstract: A scanned beam display is operable to compensate for variations in apparent pixel brightness arising from variations in beam scanning velocity and/or pixel dwell times. A compensation circuit modifies pixel values according to their scanning velocity and/or dwell time.

Abstract: An apparatus, system, and method provide management of fitness activities by providing a randomized presentation of fitness activities to a user. A plurality of fitness cards arranged in a flexible and resilient card holder provide a user with a system and method for managing fitness activities. Each of the fitness cards includes a fitness activity description that may include any combination of fitness activity identifiers, images, and instructions.