Acousto-optic element light deflector light beam scanning apparatus and image recording apparatus

摘要

An xyz coordinate system is determined so that a z-axis may coincide with an incident direction of an incident light, an x-axis may coincide with a polarizing direction of the incident light and a y-axis may be defined as the right-handed system from the z-axis and x-axis. An acousto-optic element is rotated around the z-axis, around the axis in a direction of propagation of an ultrasonic wave and around an axis B perpendicular to a plane formed by the z-axis and the direction of propagation of the ultrasonic wave, so that the attitude of the acousto-optic element to the incident light is adjusted.